WO2018079713A1 - Method for producing coal briquette fuel and coal briquette fuel - Google Patents

Abstract

Provided are a method for producing coal briquette fuel and a coal briquette fuel that enable the desired strength to be achieved at a low cost. This method for producing coal briquette fuel comprises: a crushing step 10 for crushing coal 1; a drying step 20 for drying coal 2 that was crushed in the crushing step 10; a grinding step 30 for grinding coal 3 that was dried in the drying step 20 to obtain coal particles 4; a shaping step 40 for shaping the coal particles 4 obtained in the grinding step 30 into a plate shape to obtain an intermediate briquette 5 containing a briquette 100; and a sieving step 50 for removing powder included in the intermediate briquette 5 obtained in the shaping step 40. The coal particles 4 obtained in the grinding step 30 have a mean particle size of 10 to 60 μm. A briquette 100 which is obtained in the shaping step 40 and from which the powder has been removed in the sieving step 50 is used as coal briquette fuel.

Description

Coal molded fuel manufacturing method and coal molded fuel

The present invention relates to a method for producing a coal-molded fuel obtained by pulverizing and molding coal, and a coal-molded fuel.

Conventionally, as a technology for obtaining fuel using coal as a raw material, low-grade coal is mixed with oil to form a slurry, and this slurry is heated to dehydrate the coal, reduce the water content, and then pulverize and mold to form a solid A technique for obtaining fuel is disclosed in Patent Document 1. Patent Document 2 (WO2015 / 098935) discloses a coal-molded fuel obtained by molding coal particles using only coal as a raw material without using a binder or the like, and a method for producing the same.

JP 2011-1111529 A WO2015 / 098935

However, in the technique described in Patent Document 1, since a slurry is prepared by mixing coal with oil, a material other than coal is required, which causes an increase in cost. In addition, the solid fuel is required to have a certain strength that does not cause the solid fuel to collapse when the solid fuel after molding is handled. However, Patent Document 1 does not describe the strength of the solid fuel. In addition to not solving this problem, Patent Document 2 also has various problems described later.

One of the main inventions of the present application is to provide a method for producing a coal molded fuel having a desired strength at a low cost and a coal molded fuel. Other purposes will be explained in each part.

Each aspect of the present invention is as follows.

<First Mode (Part A)>
Crushing process of crushing coal;
A drying step of drying the coal crushed in the crushing step;
A pulverizing step of pulverizing the coal dried in the drying step to obtain coal particles;
Molding the coal particles obtained in the pulverization step into a plate shape, and a molding step for obtaining an intermediate molded body including a molded body;
A sieving step for removing the powder contained in the intermediate molded body obtained in the molding step;
Have
The coal particles obtained in the pulverization step have an average particle size of 10 to 60 μm,
A method for producing a coal-molded fuel, characterized in that the molded body obtained in the molding step and from which the powder has been removed in the sieving step is used as a coal-molded fuel.

A coal-molded fuel obtained from a coal-particle shaped body,
The coal particles have an average particle size of 10 to 60 μm,
The moisture is 5 to 20 wt%, the apparent density is 1.2 to 1.4 g / cm ³ , the bulk density is 0.4 to 0.6, and
A first fracture piece having two types of surfaces, a smooth surface to which a smooth molding surface is transferred, and a fracture surface;
A second fractured piece having two types of surfaces, an irregular surface to which a molding surface having irregularities is transferred, and a fracture surface;
A third fracture piece having three types of surfaces, the smooth surface, the irregular surface, and the fracture surface;
The surface is a fourth fracture piece with only a fracture surface,
A coal-molded fuel characterized by being a mixture of one or more of the above.

<Second Mode (Part B)>
A method for curing modified coal that retains modified coal under predetermined curing conditions,
The predetermined curing conditions are a temperature of -5 to 40 ° C., a relative humidity of 5 to 95%, and a modified coal curing method characterized by being 200 days or longer.

<Third Aspect (Part C)>
A method for curing modified coal that retains modified coal under predetermined curing conditions,
The method for curing modified coal, wherein the predetermined curing conditions are a temperature of 60 to 120 ° C. and a time of 15 to 60 minutes.

<Fourth aspect (part D)>
A first crushing step of crushing coal;
A drying step of drying the coal crushed in the first crushing step;
Crushing the coal dried in the drying step to obtain coal particles having an average particle size of 10 to 60 μm;
A first molding step of molding the coal particles having a water content of 5 to 20 wt% to obtain a first molded body;
A second crushing step of crushing the first molded body to generate a second crushed material;
A second molding step of molding the second crushed material again to produce a second molded body having an apparent density of 1.2 to 1.4 g / cm ³ ;
A method for producing a coal-molded fuel having
In the first molding step, a horizontal supply type molding machine is used.

<Fifth aspect (Part E)>
A method for producing a coal molded body molded by a vertical supply / discharge molding machine that molds coal particles supplied from vertically above and discharges the molded coal molded body vertically downward,
The coal particles have an initial volume per unit weight of Vo, a volume at the time of tapping N times as V _N , and a degree of bulk reduction as C = (Vo−V _N ) / Vo.
Formula (1): N / C = (1 / ab) + (1 / a) N
In
Condition (1): a ≦ 0.29
Condition (2): 20 ≦ 1 / b ≦ 60
A method for producing a coal molding characterized by satisfying any of the above.

According to one aspect of the present invention, a coal-molded fuel having a desired strength can be provided at a low cost. The effects related to other aspects will be described in each part.

It is a figure which shows the manufacturing process of the coal molding fuel by Embodiment 1 of this invention. It is a schematic diagram of the briquette machine which can be used suitably at a formation process. It is a top view of an example of the roll pocket formed in the roll surface of a briquette machine. It is a figure which shows the cross-sectional shape of the roll pocket shown to FIGS. 1-3A. It is a figure which shows the example of the arrangement pattern of the groove | channel formed in the roll surface of a briquette machine. It is a figure which shows the cross section of a 1st broken piece typically. It is a figure which shows the cross section of a 2nd broken piece typically. It is a figure which shows typically the cross section of a 3rd broken piece. It is a figure which shows typically the cross section of a 4th broken piece. It is a photograph of the molded object 100 which is a mixture of various broken pieces. It is a figure which shows the manufacturing process of the coal molding fuel by Embodiment 2 of this invention. It is a figure which shows the cross-sectional shape of the roll pocket (shape A) formed in the roll surface of the briquette machine used in the molding process of Example 1-1 and Example 1-2. FIG. 8B is a diagram showing a planar shape of the roll pocket (shape A) shown in FIG. 1-8A. In Example 1-1 and Example 1-2, it is a figure which shows the cross-sectional shape of the roll pocket (shape B) formed in the roll surface of the briquette machine used at the formation process. FIG. 9B is a diagram showing a planar shape of the roll pocket (shape B) shown in FIG. 1-9A. In Example 1-1 and Example 1-2, it is a figure which shows the structure of the testing apparatus used in order to obtain | require the natural heat index of coal. It is a figure which shows the manufacturing process of the modified coal (product 100) in Embodiment B1. It is a figure which shows the manufacturing process of the modified coal (product 200) in Embodiment B2. It is a schematic diagram of the briquette machine which can be used suitably at a formation process. It is the figure (a) which shows the cross-sectional shape of the roll pocket (shape A) formed in the roll surface of the briquette machine used at the formation process of an Example, and the figure (b) which shows a planar shape. It is the figure (a) which shows the cross-sectional shape of the roll pocket (shape B) formed in the roll surface of the briquette machine used at the formation process of an Example, and the figure (b) which shows a planar shape. In an Example, it is a figure which shows the relationship between the curing days and the water | moisture content of the 7th day immersed in water. It is a figure which shows the relationship between the curing days and the thickness of the molded object before being immersed in water in an Example. In an Example, it is a figure which shows the relationship between the curing days and the expansion coefficient of the molded object after being immersed in water for 7 days. It is a figure which shows the manufacturing method of the modified coal which concerns on one form of invention of Part C. It is a figure which shows typically the structure of a briquette machine. It is a figure which shows typically the shape of the recessed part (pocket) formed in the roll surface, and the shape of the shape | molded molded object. It is a figure which shows the manufacturing process of the coal molding fuel in Embodiment D1. It is a figure which shows the manufacturing process of the coal molding fuel in Embodiment D2. It is a schematic diagram of the compactor which can be used suitably at a formation process. It is a schematic diagram of the briquette machine which can be used suitably at a formation process. In an Example and a reference example, it is a figure which shows the structure of the test apparatus used in order to obtain | require the spontaneous-heating index of coal. It is a figure which shows the integrated sieve passage rate of the 2nd crushed material of Example D1, and the 2nd crushed material of Reference Example D1. It is a figure which shows the manufacturing process of the coal molding by one Embodiment of the invention of Part E. It is a schematic diagram of the briquette machine which can be used suitably at a formation process. It is a top view of an example of the roll pocket formed in the roll surface of a briquette machine. It is a figure which shows the cross-sectional shape of the roll pocket shown to FIGS. 5-3A. It is a figure which shows an example of the arrangement pattern of the groove | channel formed in the roll surface of a briquette machine. It is a figure which shows the manufacturing process of the coal molding fuel by Embodiment F1 of the invention of Part F. FIG. 6 is a schematic diagram of an example of a rotary molding machine that can be used in the molding process shown in FIG. 6-1. It is a top view of an example of the roll pocket formed in the roll surface of a rotary molding machine. It is a figure which shows the cross-sectional shape of the roll pocket shown to FIGS. 6-2A. It is a figure which shows an example of the arrangement pattern of the groove | channel formed in the roll surface of a rotary molding machine. FIG. 7 is a schematic view of another example of a rotary molding machine that can be used in the molding process shown in FIG. 6-1. FIG. 6 is a schematic diagram of an example of a piston-type compression molding machine that can be used in the molding process shown in FIG. 6-1. It is a figure which shows the manufacturing process of the coal molding fuel by Embodiment F2 of the invention of Part F. It is a figure explaining the measuring method of the tensile strength in Example F2 and 3. It is a graph which shows the relationship between shaping | molding process inlet_port | entrance temperature and tensile strength in Example F2 and 3. It is a graph which shows the relationship between a shaping | molding process inlet_port | entrance temperature and an apparent density in Example F2 and 3. It is a graph which shows the relationship between the total water | moisture content and immersion water | moisture content in Example F5.

This application discloses inventions according to the first to sixth aspects (referred to as part A's invention, etc. as necessary) as main inventions, and these are divided into parts A to F for explanation. To do. The description is independent for each part, but the disclosure of other parts may be referred to as long as it does not contradict the gist of the invention of the part. The inventions of Part A to Part F constitute independent inventions, but may have two or more invention features selected from the inventions of Part A to Part F together. About a code | symbol, the member and element which differ for every part may be shown. In Part A, “present invention” means the invention of Part A.

<< Part A >>
The present invention relates to a method for producing a coal-molded fuel obtained by pulverizing and molding coal, and a coal-molded fuel.

The main items disclosed in Part A are as follows. Note that the reference does not limit the disclosed content.

(1) crushing step 10 for crushing coal 1;
A drying step 20 for drying the coal 2 crushed in the crushing step 10;
A pulverization step 30 for pulverizing the coal 3 dried in the drying step 20 to obtain coal particles 4;
Molding step 40 to obtain the intermediate molded body 5 including the molded body 100 by molding the coal particles 4 obtained in the grinding step 30 into a plate shape;
A sieving step 50 for removing the powder contained in the intermediate molded body 5 obtained in the molding step 40;
Have
The coal particles 4 obtained in the pulverizing step 30 have an average particle size of 10 to 60 μm,
A method for producing a coal-molded fuel, characterized in that the molded body 100 obtained in the molding step 40 and from which the powder has been removed in the sieving step 50 is used as a coal-molded fuel.

According to this manufacturing method, since the molding pressure can be reduced, the coal molding fuel can be manufactured at a low cost.

(2) In the method for producing a coal-molded fuel described in (1) above,
In the molding step 40, using a molding machine having a molding means and a supply means for supplying the coal particles 4 to the molding means,
The method for producing a coal-molded fuel, wherein the supply means is a screw-type supply means.

Using a screw-type supply means, coal particles can be easily supplied to the molding means. Further, as a result of variations in the supply pressure depending on the location, a distribution of strength is generated in the plate-shaped molded body. However, since the weak portion collapses after molding, the remaining high strength portion can be obtained as coal-molded fuel.

(3) In the method for producing a coal-molded fuel according to (1) or (2) above,
A method for producing a coal-molded fuel, characterized in that no binder is added.

According to this production method, a coal-molded fuel having a desired strength can be produced efficiently at low cost without using a binder.

(4) In the method for producing a coal-molded fuel according to any one of (1) to (3) above,
The molding step 40 includes supplying the coal particles 4 between two rotating rolls 41,
The method for producing a coal-molded fuel, wherein at least one surface of the two rolls 41 has irregularities.

According to this manufacturing method, it is possible to more reliably suppress the supplied coal particles from slipping off the roll and improve the molding efficiency.

(5) In the method for producing a coal-molded fuel according to (4) above,
A method for producing a coal-molded fuel, wherein a clearance between the two rolls 41 is 3 mm or less.

According to this manufacturing method, it is possible to suppress a decrease in density strength and a decrease in yield of the plate-shaped molded body by appropriately setting the clearance.

(6) In the method for producing a coal-molded fuel according to any one of (1) to (5) above,
When the crushing step 10 is the first crushing step 10 and the molding step 40 is the first molding step 40,
After the first molding step 40, a second crushing step 10a for crushing the intermediate molded body 5 which is the molded body obtained in the first molding step 40;
After the second crushing step 10a, a second molding step 40a for remolding the intermediate molded body 5 crushed in the second crushing step 10a,
Further comprising
At least in the first molding step 40, a horizontal supply type compactor is used.

According to this manufacturing method, the molding efficiency can be further improved.

(7) A coal-molded fuel obtained from a molded body 100; 200 of coal particles 4,
The coal particles 4 have an average particle size of 10 to 60 μm,
The moisture is 5 to 20 wt%, the apparent density is 1.2 to 1.4 g / cm ³ , the bulk density is 0.4 to 0.6, and
A first fracture piece having two types of surfaces, a smooth surface to which a smooth molding surface is transferred, and a fracture surface;
A second fractured piece having two types of surfaces, an irregular surface to which a molding surface having irregularities is transferred, and a fracture surface;
A third fracture piece having three types of surfaces, the smooth surface, the irregular surface, and the fracture surface;
The surface is a fourth fracture piece with only a fracture surface,
A coal-molded fuel characterized by being a mixture of one or more of the above.

Since this coal-molded fuel can be produced with a low molding pressure, it has a desired mechanical strength and can be used as a low-cost fuel.

(8) In the coal-molded fuel described in (7) above,
The third broken fragment is
A 3A fracture piece in which the smooth surface and the uneven surface face each other;
The smooth surface and the uneven surface are adjacent in the same plane, and the opposing surface is a 3B fracture fragment, which is a fracture surface;
Have
A coal-molded fuel characterized in that a thickness of the smooth surface and the uneven surface in the 3A fracture fragment is 4.0 to 13.0 mm.

This coal-molded fuel is a handleable coal-molded fuel that can be molded without adding a binder and without excessively increasing the molding pressure.

(9) In the coal-molded fuel described in (7) above,
The first fragment is
A 1A fracture piece in which the smooth surfaces face each other;
A 1B fracture piece whose opposing surface of the smooth surface is the fracture surface;
And the thickness of the smooth surfaces in the 1A fracture piece is 2 to 10 mm.

This coal-molded fuel is a handleable coal-molded fuel that can be molded without adding a binder and without excessively increasing the molding pressure.

(10) In the coal-molded fuel according to any one of (7) to (9) above,
A coal-molded fuel characterized by having an HGI of 40 or more.

According to the invention of Part A, it is possible to provide a coal-molded fuel having a desired strength at a low cost. Hereinafter, an embodiment of the invention of Part A will be described.

[Embodiment 1]
Referring to FIG. 1-1, a process for producing a coal-molded fuel according to Embodiment 1 of the present invention is shown. In Embodiment 1, the process for producing coal-molded fuel includes a crushing process 10, a drying process 20, a pulverizing process 30, a molding process 40, and a sieving process 50. The coal thus produced is pulverized to obtain coal particles 4. The coal particles 4 are molded into a plate shape to obtain an intermediate molded body 5. The intermediate molded body 5 includes a plate-shaped molded body 100 and coal powder, and the molded body 100 obtained by removing the powder from the intermediate molded body 5 is used as a coal molded fuel. The powder contained in the intermediate molded body 5 is generated when the intermediate molded body 5 is cracked by the coal particles 4 that have not been molded in the molding step 40 and passed through the molding machine, and by external force received by handling the intermediate molded body 5 or the like. Containing fine pieces of coal.

As the coal 1 used as a raw material, lignite or subbituminous coal having a water content of 25 wt% or more can be used. Preferably, lignite with a water content of 30 wt% or more can be used. In a series of manufacturing processes of coal-molded fuel, only coal is used as a raw material, and additives such as a binder are not used. Use of an additive such as a binder increases the cost. However, in this embodiment, since only coal is used without adding a binder, a coal-molded fuel can be obtained at low cost.

In the crushing step 10, the coal 1 is crushed using an appropriate crushing means such as a jaw crusher or a hammer crusher to obtain a crushed coal 2. The obtained crushed coal 2 is supplied to the drying step 20. In the crushing step 10, the coal 1 may be crushed to a size that can be charged into a ball mill or the like used in the subsequent crushing step 30, and is not particularly limited. However, the size of the crushed coal 2 is preferably the maximum particle size, It is 70 mm or less, more preferably 50 mm or less, still more preferably 20 mm or less, and particularly preferably the average particle diameter is 1 mm to 20 mm. Here, the average particle size of the coal crushed in the crushing step 10 is measured based on “5. Particle size test method” of JIS M 8801-4, and the passing sieve mass percentage of each sieve opening is obtained. The particle diameter at which the mass percentage is 50% is defined as the average particle diameter.

In the drying step 20, the crushed coal 2 is dried using an appropriate dryer such as an indirect dryer to obtain the dried coal 3. The obtained dried coal 3 is supplied to the grinding step 30. As the indirect dryer, for example, a steam tube dryer can be used. Since a large amount of processing is required in the production of solid fuel, a steam tube dryer having a large heat transfer area and capable of performing a large amount of drying processing is suitable as a dryer used in the drying step 20.

In the pulverizing step 30, the dried coal 3 is pulverized by an appropriate pulverizer to obtain the coal particles 4. The obtained coal particles 4 are supplied to the molding step 40. As the pulverizer, a dry pulverizer or a dry pulverizer pulverizer can be preferably used. Among them, a ball mill or a roller mill that can finely pulverize and is suitable for mass processing can be preferably used. This is because, in the production of solid fuel, as in the drying step 20, a large amount of processing is required in the pulverizing step 30.

The average particle diameter of the coal particles 4 obtained in the pulverization step 30 is 10 to 60 μm, preferably 10 to 50 μm, more preferably 10 to 30 μm. The average particle diameter of the coal particles 4 is given by the median diameter of the particle size distribution obtained by the laser diffraction / scattering method. In the present specification, the “coal particles” mean the coal particles 4 pulverized in the pulverization step 30.

By making the average particle diameter of the coal particles 4 obtained in the pulverization step 30 within the above range, when the fine coal particles 4 are molded in the molding step 40, the filling rate into the mold (for example, roll pocket) increases. A desired strength can be obtained by improving the density of the molded body 100 described later.

In addition, since the ball mill and the roller mill can be dried simultaneously with the pulverization, the ball mill and the roller mill can be dried in the pulverization step 30. However, since it is difficult to sufficiently dry the crushed coal 2 with the drying capability of the ball mill and the roller mill, in this embodiment, the drying step 20 is provided before the pulverization step 30 to sufficiently dry the coal particles 4. Have gained.

The molding step 40 includes molding the coal particles 4 into a plate shape using a molding machine. The molding machine has a molding means for pressure-molding the raw material and a supply means for supplying the raw material to the molding means. As such a molding machine, for example, a briquette machine can be used. FIG. 1-2 shows a schematic diagram of a briquette machine that can be suitably used in the molding step 40. The briquette machine shown in FIG. 1-2 is a vertical supply type briquette machine, and is disposed between the pair of rolls 41 as a forming means and the pair of rolls 41, and is a raw material between the pair of rolls 41. Supply means 42 for supplying the coal particles 4. The supply means 42 includes a hopper to which the coal particles 4 are supplied, a screw feeder that sends the coal particles 4 in the hopper downward, and the like. Each of the pair of rolls 41 has a rotation shaft that is driven by appropriate driving means. The rotation shafts extend in the horizontal direction and are arranged in parallel to each other with an interval in the horizontal direction. The pair of rolls 41 are arranged with a gap. The plate-shaped molded body 100 formed by pressurizing the coal particles 4 and the pressurization by feeding the coal particles 4 supplied to the gap from above the roll 41 downward while being pressed by the rotational drive of the roll 41. Instead, an intermediate molded body 5 including the coal particles 4 leaking from between the rolls 41 is obtained.

If the gap (clearance) between the pair of rolls 41 is too wide, leakage of the coal particles 4 from between the rolls 41 and pressure dispersion are likely to occur, and the density and strength of the resulting molded body 100 are reduced, and the yield. Leading to a decline. Therefore, the gap between the rolls 41 is preferably 3 mm or less. By setting the gap between the rolls 41 to 3 mm or less, a plate-like molded body with sufficient strength can be obtained. Due to the clearance between the rolls 41, the obtained molded body 100 has a plate shape.

Further, it is preferable that unevenness is formed on the surface of at least one of the pair of rolls 41. Thereby, it is suppressed that the coal particle 4 supplied between the rolls 41 slips down from the surface of the roll 41, and the coal particle 4 can be hold | maintained favorably between the rolls 41. FIG. Moreover, since the coal particles 4 are filled in the recesses by forming the unevenness, the processing amount per unit time can be increased. In addition, when the surface of the roll 41 has irregularities, the irregularities on the surface of the roll 41 are transferred as the surface shape of the molded body 100 to be obtained.

The shape of the unevenness formed on the surface of the roll 41 is not particularly limited, and may be, for example, a roll pocket (concave portion), a groove, or a combination thereof. Moreover, a roll pocket may be provided in both the two rolls 41, and may be provided only in one side. When the unevenness is formed by roll pockets, the shape of the roll pocket is arbitrary and may be, for example, an ellipse.

When the unevenness is formed by roll pockets, the shape of the roll pocket can be arbitrary. An example of a roll pocket is shown in the figure. FIGS. 1-3A and 3B are examples in which roll pockets having an elliptical opening are formed on both rolls, whereby a molded body 100 having double-sided almond-shaped projections is obtained.

Table A1 shows preferred dimensions (design values) and dimension ranges of each part of the illustrated roll pocket.

Also, when the irregularities are formed by grooves, the width, depth, arrangement, etc. of the grooves can be arbitrary. The groove may be parallel or orthogonal to the axial direction of the roll 41, or may be inclined. 1-4 shows an example in which a plurality of grooves parallel to the axial direction A of the roll 41 are arranged.

The intermediate molded body 5 obtained by the molding process 40 is subjected to the sieving process 50 to remove the powder, and the remaining molded body 100 is obtained as a coal molded fuel. In the sieving step 50, a vibration sieving machine can be used. As the vibrating sieve, a circular sieve, a trommel sieve, or the like is used, and among them, those capable of continuous / mass processing are preferable.

The obtained molded body 100 has an apparent density of 1.2 to 1.4 g / cm ³ and a bulk density of 0.4 to 0.6. The water content of the molded body 100 is 5 to 20 wt%, preferably 8 to 18 wt%, more preferably 10 to 17 wt%. This moisture is derived from the moisture of the coal particles 4. Here, the apparent density is a value measured based on “8. Method for measuring density and specific gravity by submerged weighing method” of JIS Z 8807.

The bulk density was calculated by the following formula 1 from the weight of the filled sample and the volume of the container after the sample was ground and filled into a cylindrical container of about 2 to 5 L having a known volume. In addition, when thrown into a container, it filled so that a sample might not be consolidated as much as possible.
Bulk density = Mass of filled sample ÷ Volume of container (Formula 1)

The water content is a value measured based on “Measurement method of total water content of coals” of JIS M 8820-0. Moreover, it is preferable that the molded object 100 is HGI 40 or more.

Since the moisture derived from the coal particles 4 plays a role of a binder in the molding process 40, the molding 100 can be efficiently molded without adding a binder or a binder separately by adjusting the moisture of the molded body 100 to the above range. It becomes possible. The water content of the coal particles 4 used in the molding step 40 is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and even more preferably 10 to 17 wt%.

In this embodiment, since the average particle diameter of the coal particles 4 is as fine as 10 to 60 μm, the filling rate of the coal particles 4 into the roll pockets and grooves of the briquette machine increases during molding. Thereby, the density of the molded object 100 improves and it contributes to the intensity | strength improvement of the molded object 100. FIG. Further, the moisture contained in the coal 1 is used as a binder, and the preferred moisture range is 5 to 20 wt%, and the density of the molded body 100 is regulated, and more preferably, the size and weight of the molded body 100 are determined. It is also possible to adjust to a region where the crushing strength of the molded body 100 is maximized. Therefore, when using the molded body 100 as a coal molding fuel, the pulverization during transportation is reduced and handling properties are reduced. Can be improved. Moreover, by molding after pulverization, the specific surface area is also reduced, and ignition during storage of coal-molded fuel can be reduced. Furthermore, the manufacturing process for obtaining the molded body 100 uses all known machines and devices, and does not require hot water or the like, so that the cost can be reduced.

As described above, in this embodiment, the molded body 100 is obtained without using a binder. By defining the particle diameter and moisture of the coal particles 4 and the density of the molded body 100 within the above ranges, the strength of the molded body 100 can be set to a desired value at low cost without adding a separate binder. .

Here, when supplying the coal particles 4 to the molding means, such as when the molding machine used in the molding step 40 has a screw-type supply means, the supply pressure distribution of the coal particles 4 varies depending on the location. This variation in the distribution of supply pressure affects the mechanical strength of the molded body 100, and the molded body 100 is broken into a plurality of pieces at a weak portion by an external force received by processing, handling, transportation, storage, etc. after molding. There is. However, since the coal-molded fuel is finely pulverized again at the thermal power plant, it is not necessary for all the molded bodies 100 to have a uniform shape like briquettes. Various shapes may be mixed.

Further, even if the molded body 100 is broken by handling or the like, the broken pieces are present as a lump having a high mechanical strength as compared with the case where the coal particles 4 are molded not as a plate but as a briquette. In addition, by molding the coal particles 4 into a plate shape in the molding step 40, the molding pressure can be reduced as compared with a case where a uniform shape such as briquette is used. The fact that the molding pressure can be reduced means that molding can be performed with less energy, and as a result, low-cost coal molding fuel can be obtained. On the other hand, it is also possible to obtain a molded body 100 having a strength capable of maintaining a uniform shape without cracking during handling. However, this requires molding at a high molding pressure or adding a binder to the raw material, resulting in an increase in the cost of coal-molded fuel.

As described above, the fragments of the molded body 100 obtained by molding the coal particles 4 into a plate shape have sufficient mechanical strength and can be used as a low-cost fuel. It can be said that the molded body 100 used as the molded fuel is a mixture of the broken pieces.

More specifically, the molded body 100 obtained as the coal-molded fuel through the sieving step 50 is a mixture of one or more of the following first to fourth broken pieces. The first to fourth broken pieces are shown in FIGS. 1-5A to 1-5D, and a molded body 100 which is a mixture thereof is shown in FIG. 1-6. A smooth surface, an uneven surface, and a fracture surface will be described later.

1st broken piece: As shown in FIGS. 1-5A, it has two types of surfaces, a smooth surface 101 to which a smooth molding surface is transferred and a broken surface 103.
Second broken piece: As shown in FIG. 1-5B, the broken surface has two types of surfaces, a concavo-convex surface 102 onto which a concavo-convex molding surface is transferred and a fractured surface 103.
Third fracture piece: As shown in FIG. 1-5C, the fracture surface has three types of surfaces, the smooth surface 101, the irregular surface 102, and the fracture surface 103.
Fourth fracture fragment: As shown in FIGS. 1-5D, the surface is only the fracture surface 103.

The third broken fragment is
A 3A fracture piece in which the smooth surface 101 and the uneven surface 102 face each other;
A 3B fracture piece in which the smooth surface 101 and the concave-convex surface 102 are adjacent in the same plane, and the opposing surface is a fracture surface;
You may have. In this case, it is preferable that the 3A broken piece has a thickness between the smooth surface and the uneven surface of 4.0 to 13.0 mm.

The thickness of the 3A fracture piece reflects the maximum thickness of the molded body 100. If the thickness exceeds this range, the mechanical strength as a coal-molded fuel may not be ensured. If the thickness is less than this range, the molding efficiency decreases. Within this range, it is possible to obtain a molded body 100 that can be handled without adding a binder and without excessively increasing the molding pressure.

The first fragment is
A first A fracture piece in which the smooth surfaces 101 face each other;
A 1B fracture fragment whose opposing surface of the smooth surface 101 is a fracture surface 103;
You may have. In this case, the 1A broken piece preferably has a thickness between the smooth surfaces 101 of 2 to 10 mm.

The thickness of the 1A fracture piece is the thickness of the portion of the molded body 100 sandwiched between the molding means where the irregularities are not formed, for example, when the molding means has a pair of rolls with smooth surfaces. Corresponds to the clearance of the roll. If the thickness exceeds this range, the mechanical strength as a coal-molded fuel may not be ensured. If the thickness is less than this range, the molding efficiency decreases. Within this range, it is possible to obtain a molded body 100 that can be handled without adding a binder and without excessively increasing the molding pressure.

Here, the “smooth surface” means a surface formed by pressurizing a portion of the surface of the forming means, for example, the surface of the roll where no irregularities are formed during the forming in the forming step 40. To do. The “uneven surface” means a surface formed by pressurizing the surface of the forming means, for example, the surface of the roll where the unevenness is formed during the forming in the forming step 40. The “fracture surface” is a surface different from the “smooth surface” and the “uneven surface”, and is not in contact with the surface of the molding means during molding in the molding process 40 and is exposed by cracking of the molded body 100. Surface or surface that is not subjected to molding pressure from the roll when passing through the roll (surfaces on both ends in the axial direction of the roll in the aggregate of coal particles 4 passing through the roll), or derived from the roll pocket once molded This means the surface of the convex surface that has fallen off due to insufficient strength (peeled surface).

[Embodiment 2]
Referring to FIGS. 1-7, a process for producing a coal-molded fuel according to Embodiment 2 of the present invention is shown. The basic manufacturing procedure is the same as that of the first embodiment, but in the second embodiment, the second crushing process 10a is provided after the molding process 40 in the first embodiment, and the second molding process 40a is also provided at the subsequent stage. This is different from the first embodiment.

Therefore, in the second embodiment, the crushing process and the molding process common to the first embodiment are distinguished from the second crushing process 10a and the second molding process 40a as the first crushing process 10 and the first molding process 40, respectively. In addition, the first intermediate molded body 5 is obtained in the first molding step 40. The density of the first intermediate molded body 5 (from which fine powder has been removed with a 2-5 mm sieve) in the second embodiment is preferably lower than the density of the molded body 100 in the first embodiment. The first intermediate molded body 5 includes, in addition to the plate-shaped molded body, the coal particles 4 that have passed between the rolls without being molded and the molded body that has collapsed due to insufficient compression. The apparent density of the first intermediate molded body 5 excluding the molded body is preferably 1.00 g / cm ³ to 1.25 g / cm ³ . When removing the coal particles 4 and the molded body that has collapsed due to insufficient compression from the first intermediate molded body 5, it is preferable to use a 2-5 mm sieve mesh. The crushing strength is preferably 10 to 800N. In addition, the moisture content of the coal particles 4 used in the first molding step 40 is preferably 5 to 20 wt%, more preferably 8 to 16 wt%, and further preferably 10 to 17 wt%.

In the first molding step 40 of Embodiment 2, a compactor that is a horizontal supply type molding machine that supplies raw materials in the horizontal direction can be preferably used. Similar to the briquette machine, the compactor also has a molding means for molding the raw material and a supply means for supplying the raw material to the molding means. A shaping | molding means can have a pair of roll, for example, By supplying a raw material between this roll, a raw material is pressure-molded between rolls with rotation of a roll. However, in the horizontal supply type compactor, two rolls are arranged one above the other. By using a horizontal supply type compactor in the first molding step 40, the yield of the first intermediate molded body 5 obtained, that is, the molding efficiency is improved.

In the 2nd crushing process 10a, the 1st intermediate molded object 5 is crushed with a crusher, and the crushed material 6 (henceforth crushed material 6) of the 1st intermediate molded object 5 is obtained. The crusher may be the same as that used in the first crushing step 10. The crushed material 6 preferably has a particle size of 0.1 to 1.0 mm, more preferably 0.15 to 0.9 mm, and still more preferably 0.2 to 0.8 mm. Moreover, it is preferable that the largest particle diameter of the crushed material 6 is below the length of the shorter one among the two sides of the particle diameter of the molded object 200 mentioned later. By adjusting the second crushing step 10a so that the crushed material 6 falls within the range of the average particle size and the maximum particle size, the crushed material 6 into the roll pocket in the briquette machine at the time of molding in the second molding step 40a. The filling rate can be improved. The second intermediate molded body 7 obtained as a result shows superior quality (crushing strength and apparent density) compared to the molded body 100 that is the final product (coal molded fuel) of the first embodiment. In the second embodiment, the size (particle diameter) of roll pockets used in the first molding step 40 and the second molding step 40a may not be the same.

In the second molding step 40a, the second intermediate molded body 7 is obtained by molding the crushed material 6 with a molding machine. Similar to the intermediate molded body 5 in the first embodiment, the second intermediate molded body 7 includes a plate-shaped molded body 200 and coal powder, and the powder is removed from the second intermediate molded body 7 through the sieving step 50. The molded body 200 obtained by doing so is used as a coal molded fuel.

As the molding machine used in the second molding step 40a, a briquette machine that is a vertical feeding type molding machine as described in the first embodiment can be used. Alternatively, similarly to the first molding step 40, a horizontal supply type compactor can be used in the second molding step 40a.

The particle size of the molded body 200 is preferably 5 to 40 mm. The apparent density of the molded body 200 is 1.2 to 1.4 g / cm ³ . The weight of the molded body 200 is preferably 0.2 to 20 g. The moisture content of the molded body 200 is 5 to 20 wt%, preferably 8 to 18 wt%, more preferably 10 to 17 wt%.

As described above, in the second embodiment, the first intermediate molded body 5 once molded is crushed again in the second crushing step 10a and molded again in the second molding step 40a. The first intermediate molded body 5 is in a state where the density has already been increased to some extent by the first molding step 40, and the crushed material 6 also has the same density. Therefore, by molding the crushed material 6 again, it is possible to obtain the second intermediate molded body 7 including a molded body whose density is further improved as compared with the first intermediate molded body 5.

Further, the average particle size of the crushed coal particles 4 is 10 to 60 μm, and as it is, the fluidity in the briquette machine is poor and it may be difficult to mold. On the other hand, if it is the crushed material 6 obtained by crushing the first intermediate molded body 5 once molded, the density is increased to some extent by the first molding step 40, so the fluidity in the briquette machine is improved. Then, the molding in the second molding step 40a is performed smoothly. As a result, a molded body 200 having a higher density than that of the first intermediate molded body 5 is obtained. By using this molded body 200 as a coal-molded fuel, pulverization during storage and transportation is further reduced, and handling is possible. A coal-molded fuel with improved properties can be obtained.

In addition, you may provide the moisture adjustment process of adjusting the water content of the molded object 100 finally obtained in Embodiment 1 and the molded object 200 finally obtained in Embodiment 2. FIG. The moisture adjustment step is preferably provided after the sieving step. The moisture adjustment step can prevent product dusting and spontaneous heat generation.

In the moisture adjustment step, there is a method of spraying the molded bodies 100 and 200 conveyed on the belt conveyor to obtain a suitable moisture range. In addition, after forming the molded bodies 100 and 200 that have passed through the sieving process (stacking in a mountain shape to form a pile), the water content of the stacked molded bodies 100 and 200 is preferably within a suitable range by a watering facility including a water supply pump and a sprinkler. It may be a method of adjusting to the above.

The moisture after the moisture adjustment step of the molded bodies 100 and 200 is preferably 10 to 30 wt%, more preferably 10 wt% or more and less than 25 wt%. In the second embodiment, as in the first embodiment, the strength of the molded body 200 can be set to a desired value at a low cost without adding a binder.

The explanation of the sign of the main elements related to the description in Part A is as follows.

10 Crushing process (first crushing process)
10a Second crushing process 20 Drying process 30 Crushing process 40 Molding process (first molding process)
40a Second molding step 41 Roll 42 Supply means 50 Sieve step 100, 200 Molded body

<< Part B >>
The invention disclosed in Part B relates to a method for curing modified coal.

In Patent Document 1 (Japanese Patent Laid-Open No. 2011-111529), low-grade coal is mixed with oil to form a slurry, and the slurry is heated to dehydrate the coal, and after reducing the water content, pulverized and molded. Thus, a technique for obtaining a solid fuel is disclosed. Patent Document 2 (WO2015 / 098935) discloses a coal-molded fuel obtained by molding coal particles using only coal as a raw material without using a binder or the like, and a method for producing the same.

However, in the above-mentioned Patent Document 1 (Japanese Patent Application Laid-Open No. 2011-111529), it is necessary to prepare a slurry by mixing with oil, resulting in an increase in cost. Further, when handling the molded solid fuel, a certain level of strength is required. However, Patent Document 1 does not describe the strength. Although the coal molding fuel of patent document 2 (WO2015 / 098935 gazette) was able to reduce cost compared with the case where a binder etc. were used, since the calorific value which is a product value depends on the product moisture at the time of outdoor storage, Further improvement has been demanded so that the amount of water absorption due to rain during storage will decrease.

The invention of Part B aims to provide a method for easily producing modified coal with low immersion moisture.

The main disclosure items of Part B are as follows.

(1) A method of curing reformed coal that holds the reformed coal under predetermined curing conditions,
The predetermined curing conditions are a temperature of -5 to 40 ° C., a relative humidity of 5 to 95%, and a modified coal curing method characterized by being 200 days or longer.

According to this method, modified coal with low immersion moisture can be provided by a simple method.

(2) In the method for curing modified coal as described in (1) above,
When the water immersion moisture modified coal before curing _{W A,} the immersion in water moisture modified coal after curing and _{W B,} characterized in that it is a _{W B / W A = 0.70 ~} 0.90 Curing method for modified coal.

According to this method, modified coal with low immersion moisture can be provided by a simple method.

(3) In the method for curing modified coal according to (1) or (2) above,
The modified coal is a molded body obtained by compression molding the coal particles, the compression direction thickness of the modified coal before curing T _A, the compression direction thickness of the modified coal after curing and T _B Then, T _B / T _A = 1.0 to 1.2.

This method is preferable because the submerged expansion rate underwater due to the curing effect is sufficient.

(4) In the modified coal curing method according to any one of (1) to (3) above,
The modified coal is obtained by molding coal particles,
The coal particles have an average particle size of 10 to 60 μm and a water content of 5 to 20%,
A method for curing modified coal, wherein the apparent density of the modified coal before curing is 1.2 to 1.4 g / cm ³ .

The inventions of the above (1) to (3) can be applied to modified coal having the above characteristics.

According to the invention of Part B, modified coal with low immersion moisture can be provided by a simple method. The invention of Part B will be described below.

[Curing process]
The invention of Part B relates to a method for curing reformed coal that holds the reformed coal under predetermined curing conditions. The curing conditions are a temperature of -5 to 40 ° C. and a relative humidity of 5 to 95%, preferably 200 days or more, more preferably a temperature of 0 to 40 ° C., an ambient relative humidity of 25 to 95%, and 200 days or more. preferable. By including a process of curing the reformed coal under these conditions (hereinafter also referred to as “curing process 85”; see FIGS. 2-1 and 2-2), the water absorption of the modified coal is suppressed, Immersion moisture (simply described as “immersion moisture”) is lower than that before curing, and the quality of the modified coal is improved.

The curing method is not particularly limited, and the modified coal may be placed in an environment that satisfies the above curing conditions, including hermetic curing, air drying curing, sealing curing, wet curing, steam curing, and autoclave curing, etc. Closed curing is preferred. Of these, two or more curing methods may be combined. While the curing is being performed, the modified coal is preferably left standing, but external forces such as vibration and stirring may be applied to the extent that the modified coal is not pulverized. During the curing, the reformed coals may or may not be in contact with each other.

In regimen of the invention Part B, immersion in water moisture _{W A} of modified coal before curing, the underwater immersion moisture modified coal after curing and _{W B, W B / W A} = 0.70 ~ 0 .90 is preferred. If W _B / W _A is within this range, the effect of curing is considered to be sufficient.

Immersion moisture can be measured by the following method. The reformed coal is immersed in water, and after seven days from the start of immersion, the reformed coal is collected, and moisture adhering to the surface is removed with a cloth such as waste cloth, and then JIS M 8820-2000 (coal and coke). The total moisture obtained by the method for measuring the total moisture content of coals described in the “Class-lot total moisture measurement method” is defined as immersion moisture. The lower the immersion moisture, the lower the amount of water absorption due to rainfall during storage, etc., so the calorific value, which is the product value, increases, so it can be said that the quality of the modified coal is high.

In the Part B invention, modified coal is obtained by molding coal particles. Therefore, in the Part B invention, it is within one day from immediately after molding (immediately after the final molding process if there are multiple molding processes). Thus, the reformed coal before reaching the curing step 85 (the molded body 5 of Embodiment B1 described later or the second molded body 7 of Embodiment B2) is defined as “before curing”.

By performing curing under the above curing conditions on the modified coal (the molded body 5 of Embodiment B1 or the second molded body 7 of Embodiment B2), the water immersion expansion rate after curing is immersed in water before curing. Lowering the expansion rate, mitigating the increase in moisture during storage, and obtaining a reformed coal with a higher calorific value. As one aspect of the invention of Part B, assuming that the submerged expansion coefficient of the modified coal before curing is E _A and the submerged expansion coefficient after curing is E _B , E _B / E _A = 0.60-0.80 Is preferred. Here, the water immersion expansion coefficient is expressed by the following formula (1):

により算出することができる。

Can be calculated.

As one aspect of the invention of Part B, the modified coal (the molded body 5 of Embodiment B1 or the second molded body 7 of Embodiment B2) is a molded coal obtained by compression molding coal particles, When the thickness in the compression direction before curing is T _A and the thickness in the compression direction after curing is T _B , it is preferable that T _B / T _A = 1.0 to 1.2. In this specification, the “thickness in the compression direction” refers to a thickness in a direction in which a compressive force is applied when compression molding coal particles. It is preferable that the ratio of thickness before and after curing (T _B / T _A ) is within the above range because the underwater immersion expansion rate is sufficiently reduced by the curing effect.

As one aspect of the invention of Part B, the modified coal (the molded body 5 of Embodiment B1 or the second molded body 7 of Embodiment B2) is obtained by molding coal particles, and the coal particles have an average particle diameter. The apparent density of the modified coal before curing (molded body 5 of Embodiment B1 or second molded body 7 of Embodiment B2) having a moisture content of 10 to 60 μm and moisture of 5 to 20% is 1.2 to 1. It is preferably 4 g / cm ³ , more preferably 1.25 to 1.4 g / cm ³ . By having such physical properties, the coal particles can be formed into coal using moisture as a binder, and the modified coal before curing (the molded body 5 of Embodiment B1 or the second molded body 7 of Embodiment B2). If the apparent density of) is within this range, the modified coal is easily handled.

[Embodiment B1]
FIG. 2-1 shows an example of a modified coal production process as Embodiment B1. The manufacturing process in the embodiment B1 includes a crushing process 10, a drying process 20, a pulverizing process 30, and a molding process 40. The coal 1 as a raw material is crushed and dried, and the dried coal is pulverized to produce coal particles 4. Get. The molded body 5 obtained by molding the coal particles 4 is used as modified coal, and the molded body 5 is cured in the curing process 85 described above.

Coal 1 as a raw material is preferably lignite and / or subbituminous coal, more preferably lignite or subbituminous coal having a water content of 25 wt% or more, and more preferably lignite having a water content of 30 wt% or more. Only the coal 1 is used as a raw material, and no binder or additive is used. Although the use of additives such as a binder causes an increase in cost, the coal in the present embodiment uses only coal without adding a binder, so that coal can be obtained at low cost.

<Crushing process>
In the crushing step 10, the coal 1 is crushed with a jaw crusher or a hammark crusher to obtain a crushed coal 2, and then the drying step 20 is performed. In the crushing step 10, the coal 1 may be crushed to a size that can be charged into a ball mill or the like used in the subsequent crushing step 30, and there is no particular limitation, but the maximum particle size of the crushed coal 2 is preferably 70 mm or less. More preferably, it is 50 mm or less, more preferably 20 mm or less, and the average particle diameter is preferably about 1 mm to 20 mm. The water content of coal can be measured by the total water content measurement method for coals described in JIS M 8820-2000 (Coal and coke-lot total water content measurement method). Further, the average particle size of the coal 2 crushed in the first crushing step 10 is measured based on JISM8801-2004 “5. Particle size test method”, the passing sieve mass percentage of each sieve opening is obtained, and the passing sieve mass percentage is obtained. The particle diameter is set to 50%.

<Drying process>
In the drying step 20, the crushed coal 2 is dried by an indirect dryer to obtain the dried coal 3, and the pulverization step 30 is performed. For example, a steam tube dryer may be used as the indirect dryer. Since a large amount of processing is required in the production of solid fuel, it is preferable to use a steam tube dryer that has a large heat transfer area and can be subjected to a large amount of drying treatment.

<Crushing process>
In the pulverization step 30, the dried coal 3 is pulverized by the pulverizer, and the coal particles 4 are obtained and the process proceeds to the molding step 40. The pulverizer is a dry pulverization method or a dry pulverization method. For example, a ball mill or roller mill capable of fine pulverization and suitable for mass processing is used. As in the case of a dryer, a large amount of processing is required in the production of solid fuel, and therefore a pulverizer suitable for mass processing is preferable. In the pulverizing step 30, the average particle diameter of the coal particles 4 is preferably 10 to 60 μm, more preferably 10 to 50 μm, and still more preferably 10 to 30 μm. In order to pulverize to an average diameter of less than 10 μm, a large pulverization power is required, and production by an industrial process is difficult, so that the average diameter after ball milling is preferably 10 μm or more. In this specification, the average particle diameter of the coal particles 4 pulverized in the pulverization step 30 is the median diameter of the particle size distribution obtained by the laser diffraction / scattering method. In the present specification, the term “coal particles” means the coal particles 4 pulverized by the pulverization step 30.

By setting the average particle diameter of the coal particles 4 in the pulverization step 30 within the above range, when the fine coal particles 4 are molded in the molding step 40, the filling rate into the mold (roll pocket) is increased. The desired strength can be obtained by improving the density of the molded body 5 described later.

In addition, since the ball mill and the roller mill can be dried simultaneously with the pulverization, the ball mill and the roller mill may be dried in the pulverization step 30, but the drying capability in the ball mill and the roller mill is insufficient. It is preferable to provide a drying step 20 in advance to ensure the necessary drying capacity.

<Molding process>
In the molding step 40, the coal particles 4 are molded by a molding machine, and the obtained molded body 5 is used as modified coal. The molding machine has a molding means for pressure-molding the raw material and a supply means for supplying the raw material to the molding means. As the molding machine, for example, a briquette machine can be used.

FIG. 2-3 shows a schematic diagram of a briquette machine that can be suitably used in the molding process 40. The briquette machine shown in FIG. 2-3 is a vertical feed briquette machine, and is disposed between the pair of rolls 41 as a forming means and the pair of rolls 41, and is a raw material between the pair of rolls 41. Supply means 42 for supplying the coal particles 4. The supply means 42 includes a hopper to which the coal particles 4 are supplied, a screw feeder that sends the coal particles 4 in the hopper downward, and the like. Each of the pair of rolls 41 has a rotation shaft that is driven by appropriate driving means. The rotation shafts extend in the horizontal direction and are arranged in parallel to each other with an interval in the horizontal direction. The pair of rolls 41 are arranged with a gap. By feeding the coal particles 4 supplied to the gap from above the roll 41 downward while being pressurized by the rotational drive of the roll 41, a plate-like molded body 5 formed by pressurizing the coal particles 4 is obtained. .

If the gap (clearance) between the pair of rolls 41 is too wide, leakage of the coal particles 4 from between the rolls 41 and pressure dispersion are likely to occur, and the density and strength of the resulting molded body 5 are reduced, and the yield. Leading to a decline. Therefore, the gap between the rolls 41 is preferably 3 mm or less. By setting the gap between the rolls 41 to 3 mm or less, a plate-like molded body with sufficient strength can be obtained.

Further, it is preferable that unevenness is formed on the surface of at least one of the pair of rolls 41. Thereby, it is suppressed that the coal particle 4 supplied between the rolls 41 slips down from the surface of the roll 41, and the coal particle 4 can be hold | maintained favorably between the rolls 41. FIG. Moreover, since the coal particles 4 are filled in the recesses by forming the unevenness, the processing amount per unit time can be increased. In addition, when the surface of the roll 41 has irregularities, the irregularities on the surface of the roll 41 are transferred as the surface shape of the obtained molded body 5.

The form of the unevenness formed on the surface of the roll 41 is not particularly limited, and may be, for example, a roll pocket (concave part), a groove, or a combination thereof.

When the unevenness is formed by roll pockets, the shape of the roll pocket can be arbitrary.

The apparent density of the molded body 5 is preferably 1.2 to 1.4 g / cm ^{3, and} more preferably 1.25 to 1.4 g / cm ³ . The weight of the molded body 5 is preferably 0.2 to 20 g. The water content of the molded body 5 is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and still more preferably 10 to 17 wt%. This moisture is derived from the moisture of the coal particles 4. The apparent density can be measured based on “8. Method for measuring density and specific gravity by submerged weighing method” of JIS Z 8807.

Since the moisture derived from the coal particles 4 plays the role of a binder in the molding process 40, the molding can be efficiently molded without adding a binder or a binder by adjusting the moisture of the molded body 5 to the above range. It becomes possible. The water content of the coal particles 4 used in the molding step 40 is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and even more preferably 10 to 17 wt%.

In Embodiment B1, since the average particle diameter of the coal particles 4 is as fine as 10 to 60 μm, the filling rate of the roll pockets in the briquette machine increases during molding. As a result, the density of the molded body 5 is improved, and the strength of the molded body 5 is increased. Further, the moisture contained in the coal 1 is utilized as a binder, and a suitable moisture range is set to 5 to 20 wt%, and the density of the molded body 5 is regulated, so that the size and weight of the molded body 5 are more preferable. The crushing strength of the molded body 5 (which can be measured based on “3.1 Crushing strength test method” of JIS Z 8841-1993) can be adjusted to a maximum region. Therefore, when using the molded object 5, powdering at the time of conveyance can be reduced and handling property can be improved. Further, by molding after pulverization, the specific surface area is also reduced, and ignition during storage can be reduced. Furthermore, the manufacturing process for obtaining the molded body 5 uses all known machines and devices, and does not require hot water or the like, so that the cost can be reduced.

Note that as described above, the binder is not used in the embodiment B1. By defining the particle diameter and moisture of the coal particles 4 and the density of the molded body 5 within the above ranges, the molded body 5 can be obtained at a low cost without adding a separate binder.

<Curing process>
The molded body 5 obtained in the molding process 40 is cured in the curing process 85 described above to obtain the modified charcoal after curing in the embodiment B1 (hereinafter also referred to as the product 100). In addition, you may provide a grinding | polishing process, a sieving process, etc. between the shaping | molding process 40 and the curing process 85. FIG.

[Embodiment B2]
FIG. 2-2 shows another example of the modified coal manufacturing process as the embodiment B2. The basic configuration is the same as that of the embodiment B1, but the embodiment B1 is different from the embodiment B2 in that the second crushing step 10a is provided after the molding step 40 in the embodiment B1, and the second molding step 40a is further provided after that. And different. The reformed coal before curing in the embodiment B2 is the second molded body 7, and the second molded body 7 is cured in the curing process 85, and the modified coal after curing (hereinafter also referred to as the product 200). To get.

Henceforth, in Embodiment B2, the crushing process 10 and the shaping | molding process 40 are distinguished as the 1st crushing process 10 and the 1st shaping | molding process 40, respectively. The molded body 5 obtained in the first molding step 40 is the first molded body 5.

<First crushing step, drying step, crushing step>
The same as the crushing step 10, the drying step 20, and the crushing step 30 of the embodiment B1.

<First molding process>
In the first molding step 40, the coal particles 4 obtained in the pulverization step 30 are molded to obtain the first molded body 5. The density of the first molded body 5 in the embodiment B2 is preferably lower than the density of the molded body 5 in the embodiment B1, and the apparent density is 1.00 g / cm ³ to 1.25 g / cm ^3. preferable. As a method for obtaining the first molded body 5 having a low apparent density, for example, the rotational speed of the pushing screw at the upper part of the roll of the molding machine is decreased, the rotational speed of the roll is increased, the roll support pressure (inter-roll pressure) is decreased, and the roll pocket volume is increased. Methods such as increase and roll gap increase are listed, and these may be combined. The crushing strength is preferably 10 to 800N. In addition, the moisture content of the coal particles 4 used in the first molding step 40 is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and further preferably 10 to 17 wt%.

In the first molding step 40, a horizontal supply type molding machine (for example, a compactor) may be used, or a vertical supply type molding machine (for example, a briquette machine) may be used.

<Second crushing step>
In the 2nd crushing process 10a, the 1st molded object 5 is crushed with a crusher, the 1st molded object crushed material 6 is obtained, and it transfers to the 2nd shaping | molding process 40a. The crusher is the same as that used in the first crushing step 10. The average diameter of the first crushed product 6 is preferably 0.1 to 1.0 mm, more preferably 0.15 to 0.9 mm, and still more preferably 0.2 to 0.8 mm. Moreover, it is preferable that the maximum particle diameter of the 1st molded object crushed material 6 is below the length of the shorter one of the vertical and horizontal 2 sides of the particle diameter of the 2nd molded object 7 mentioned later. By adjusting the second crushing step 10a so that the first crushed product 6 is in the range of the average diameter and the maximum particle size, a roll pocket in the briquette machine is formed during the molding of the second molding step 40a. The filling rate can be improved. As a result, the second molded body 7 exhibits superior quality (crushing strength and apparent density) compared to the molded body 5 in Embodiment B1. In the embodiment B2, the pocket size of the roll pocket size used in the first molding step 40 and the second molding step 40a may be the same or different. The average particle diameter of the 1st molded object crushed material 6 can be measured by the method similar to the above-mentioned coal 2. FIG.

<Second molding process>
In the second molding step 40a, the first molded body crushed material 6 is molded by a molding machine to obtain the second molded body 7. The second molding step 40a can be performed in the same manner as the molding step 40 described in the first embodiment.

In the second molding step 40a, a vertical supply type molding machine (for example, a briquette machine) is used.

The particle diameter of the second molded body 7 is preferably 5 to 40 mm. The apparent density of the second molded body 7 is 1.2 to 1.4 g / cm ³ . The weight of the second molded body 7 is preferably 0.2 to 20 g. The water content of the second molded body 7 is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and still more preferably 10 to 17 wt%.

In Embodiment B2, the first molded body 5 once molded is crushed again in the second crushing step 10a, and again molded in the second molding step 40a. The first molded body 5 is in a state where the density has already been increased to some extent by the first molding step 40, and the first molded body crushed material 6 also has a similar density. Therefore, the 2nd molded object 7 whose density was further improved rather than the 1st molded object 5 can be obtained by shape | molding the 1st molded object crushed material 6 again.

Further, the average particle diameter of the pulverized coal particles 4 is 10 to 60 μm, and as it is, the fluidity in the molding machine is poor and it may be difficult to mold. On the other hand, if it is the crushed material 6 of the 1st molded object 5 once molded, since the density is raised to some extent by the 1st shaping | molding process 40, the fluidity | liquidity in a shaping | molding machine is improving, Molding is performed smoothly. As a result, a second molded body 7 having a higher density than that of the first molded body 5 is obtained, and pulverization during storage and transportation is further reduced, and the handling of the second molded body 7 and the product 200 is improved. Can be made.

<Curing process>
The second molded body 7 (modified coal before curing) obtained in the second molding step 40a is cured in the curing step 85 described above to obtain the product 200 (modified coal after curing) in Embodiment B2. . A polishing step or a sieving step may be provided between the second molding step 40a and the curing step 85. By polishing or sieving, the relatively low strength portion of the second molded body 7 is scraped off and the relatively high strength portion is left, thereby improving the strength. In the sieving step, for example, a sieve having an opening of about half of the average dimension of the vertical and horizontal dimensions of the roll pocket may be used as the sieve.

In the invention of Part B, by further subjecting the modified coal obtained as described above to a curing step, it is possible to provide a coal-molded fuel in which immersion moisture is reduced, strength is increased, and handling properties are further improved. it can.

<Moisture adjustment process>
In addition, you may provide the water | moisture-content adjustment process which adjusts the moisture content of the molded object 5 and the 2nd molded object 7 which are obtained in Embodiment B1 and Embodiment B2, respectively. The moisture adjustment process may be performed between the molding process 40 (or the second molding process 40a) and the curing process 85, or after the curing process 85. The moisture adjustment step can prevent product dusting and spontaneous heat generation.

In the moisture adjustment step, for example, after the molding step 40 of the embodiment B1 (or the second molding step 40a of the embodiment B2), a belt conveyor is arranged, and the water spray is configured by a water supply pump and a spray nozzle above the belt conveyor. There is a method of spraying water so that the moisture of the molded body 5 (or the second molded body 7) falls within a suitable range with respect to the molded body 5 (or the second molded body 7) that is provided with equipment and is conveyed by the belt conveyor. . Also, after forming the molded body 5 (or the second molded body 7) (pile is formed by depositing it in a mountain shape), the water content of the molded body piled up by a watering facility composed of a water supply pump and a sprinkler is in a suitable range. The method of adjusting so that it may become may be sufficient. In addition, the moisture may be adjusted by immersing the molded body 5 (or the second molded body 7) in water.

The explanation of the sign of the main elements related to the description of Part B is as follows.
1 Coal 2 Crushed coal 3 Dry coal 4 Coal particles 5 Molded body (first molded body)
6 1st molded object crushed material 7 2nd molded object 10 Crushing process (1st crushing process)
20 Drying process 30 Grinding process 40 Molding process (first molding process)
10a Second crushing process 40a Second molding process 85 Curing process 100 Product 200 Product

<< Part C >>
The invention disclosed in Part C relates to a method for curing reformed coal.

Conventionally, solid fuel is obtained by pulverizing and molding coal. For example, in Patent Document 2 (WO2015 / 098935), coal particles 4 obtained by pulverizing coal with a ball mill or the like are molded with a molding machine. Thus, a method for producing a solid fuel (coal-molded fuel) is disclosed.

By the way, it is assumed that coal-molded fuel is transported and stored outdoors, and is exposed to rainfall, water spray, etc., so the calorific value depends on the water absorption of the coal-molded fuel. Therefore, in order to increase the value of the coal-molded fuel, it is desirable that the moisture in the water, which is a quantitative index of water absorption, is reduced. In Patent Document 2 (WO2015 / 098935), there is no mention of performing a curing process for the purpose of reducing water immersed in water after producing coal-molded fuel in a series of processes.

The invention of Part C aims to provide a method for curing modified coal that contributes to the reduction of water immersed in water.

The main disclosure items of Part C are as follows.

(1) A method of curing reformed coal that holds the reformed coal under predetermined curing conditions,
The method for curing modified coal, wherein the predetermined curing conditions are a temperature of 60 to 120 ° C. and a time of 15 to 60 minutes.

According to this method, it is possible to provide a coal-molded fuel with reduced water immersion water.

(2) In the method for curing modified coal as described in (1) above,
_A method for curing modified coal, characterized in that W _B / W _A = 0.60 to 0.95, where W _A is water immersed in water before curing, and W _B is water immersed in water after curing.

According to this method, it is possible to provide a coal-molded fuel with reduced water immersion water.

(3) In the method for curing modified coal according to (1) or (2) above,
Water immersion expansion of pre-cured _{E A,} when the _{E B} the water immersion expansion coefficient after _curing, curing method of modified coal, which is a _{E B / E A = 0.60 ~} 0.99 .

This method is preferable because the submerged expansion rate underwater due to the curing effect is sufficient.

(4) In the modified coal curing method according to any one of (1) to (3) above,
The reformed coal is formed coal obtained by compression molding of coal particles, and TA / TA = 1.000 or more when TA is the thickness in the compression direction before curing and TB is the thickness in the compression direction after curing. A method for curing modified coal, which is 1.025.

This method is preferable because the submerged expansion rate underwater due to the curing effect is sufficient.

(5) In the method for curing modified coal according to any one of (1) to (4) above,
The modified coal is obtained by molding coal particles,
The coal particles have an average particle size of 10 to 60 μm and a water content of 5 to 20%,
A method for curing modified coal, wherein the apparent density of the modified coal before curing is 1.20 to 1.40 g / cm ³ .

The inventions of the above (1) to (4) can be applied to modified coal having the above characteristics.

(Explanation of words)
In this specification, the expression “a to b” intends that the range is a to b.

Hereinafter, embodiments of the invention of Part C will be described with reference to the drawings. FIG. 3-1 is a diagram showing a method for producing reformed coal according to an aspect of the invention of Part C. As shown in FIG. 3A, the modified coal manufacturing method of this example includes a first crushing step 10, a drying step 20, a pulverizing step 30, a first molding step 40, a second crushing step 10a, and a second molding step. 40a, sieving process 70, and heat curing process 85.

Hereinafter, each process will be described in order. In FIG. 3A, each process is shown as a block, and symbols such as “1” and “2” are attached in the vicinity of the arrows drawn toward each block. These symbols indicate coal in a predetermined state at each time point. Hereinafter, coal will be described using these symbols, but when not particularly necessary, the description will be made without using symbols.

(First crushing step: 10)
The crushing step 10 is a step of crushing the coal 1 as the supplied raw material. For crushing, a jaw crusher or a hammer crusher can be used. The degree of crushing in this step is such that the maximum particle diameter of coal is preferably 70 mm or less, more preferably 50 mm or less, more preferably 20 mm or less, and even more preferably the average particle diameter is about 1 mm to 20 mm. Also good.

Coal as raw material is lignite and / or subbituminous coal. Specifically, lignite or subbituminous coal with a total moisture of 25 wt% or more may be used, or lignite with a total moisture of 30 wt% or more.

The total moisture of coal can be measured by the total moisture measurement method of coal described in JIS M 8820-2000 (Coal and coke-lot total moisture measurement method). The average particle size of coal is determined by measuring according to JIS M8801-2004 “5. Particle size test method”, determining the passing sieve mass percentage of each sieve opening, and determining the particle size at which the passing sieve mass percentage is 50%. Is possible.

In addition, regarding coal 1, it is only coal that is used as a raw material, and it is preferable in one embodiment that no binder or additive is used.

(Drying process: 20)
The drying step 20 is a step of drying the coal 2 that has undergone the above steps. Drying may be performed using an indirect dryer. For example, a steam tube dryer can be used as the indirect dryer. An air dryer may be used.

(Crushing process: 30)
The pulverization step 30 is a step of pulverizing the coal 3 that has undergone the above-described steps with a pulverizer. The pulverizer may be either dry pulverization or dry pulverization. A ball mill or a roller mill may be used. The degree of pulverization may be such that the average particle size is preferably 10 to 60 μm, more preferably 10 to 50 μm, and even more preferably 10 to 30 μm. Pulverization may be carried out so that the average particle size is less than 10 μm, but in this case, a large pulverization power is required for the pulverization, which tends to make it difficult to manufacture in an industrial process. Therefore, pulverization with an average particle diameter of 10 μm or more using a ball mill or the like is preferable from the viewpoint of ease of process and efficiency.

The average particle size of the pulverized coal was measured based on JIS M 8801-2004 “5. Particle size test method”, the passing sieve mass percentage of each sieve opening was obtained, and the passing sieve mass percentage was 50%. This particle size is defined as the average particle size. The average particle diameter of the coal particles 4 pulverized in the pulverization step 30 is a median diameter of a particle size distribution obtained by a laser diffraction / scattering method. In this specification, the term “coal particles 4” means the particles of coal 4 pulverized in the pulverization step 30.

The coal particles 4 are then molded by a mold (details will be described later). The fact that the average particle diameter of the coal particles 4 is in the above-described range is advantageous in that the filling rate into the roll pocket of the mold can be increased. Thereby, the density of the molded body to be molded is improved, and the strength can be easily increased.

If it adds about the advantage of a ball mill or a roller mill, these are advantageous at the point which can also dry simultaneously with a grinding | pulverization. However, in the present embodiment, in order to supplement the drying ability due to these, a drying step 20 is separately provided before the crushing step 30.

(First molding step: 40)
The manufacturing method of this embodiment includes two molding steps. The 1st molding process 40 which is the 1st is a process of shape | molding the coal 4 which passed the said process with a molding machine.

The molding machine is provided with a molding means for pressure-molding the raw material and a supply means for supplying the raw material to the molding means. Specifically, a briquette machine as shown in FIG. 3-2 may be used. This briquette machine is of a vertical supply system, and includes a raw material supply unit 40B and a molding unit 40A below it.

The raw material supply unit 40B is an example, and includes a hopper 42 and a screw feeder (not shown) disposed therein. The coal particles 4 are supplied to the hopper 42, and the screw feeder is driven to rotate, whereby the coal particles 4 in the hopper 42 are sent downward, discharged from the lower end portion of the hopper 42, and supplied to the molding portion 40A below the hopper 42. It has come to be.

The molding unit 40A is an example, and has a pair of rolls 41 and driving means thereof. Although not limited, each roll 41 may be configured to rotate about a rotation axis extending in the horizontal direction. The rotating shafts are arranged substantially parallel to each other with a gap in the horizontal direction. The roll 41 has a shape such that a cylinder is turned sideways. Those having a diameter of about 250 mm and an axial length of about 50 mm may be used. The two rolls 41 are arranged in parallel to each other with a gap that allows the coal particles 4 to pass while being compressed. By supplying the coal particles 4 from the hopper 42 between the rolls 41 and rotating them, the coal particles 4 are molded and the molded body 5 is obtained.

The shape of the molded body 5 depends on the shape of a recess or the like (detailed below) formed on the surface of the roll 41, but may be a plate shape as an example.

If the gap between the rolls 41 is too wide, leakage of the coal particles 4 from between the rolls and pressure dispersion are likely to occur. These can lead to a decrease in density and strength of the molded body, and a decrease in yield. Therefore, in this embodiment, it is preferable as an example that the gap between rolls is 3 mm or less. According to this, the plate-shaped molded object with which sufficient intensity | strength was ensured can be obtained.

It is also preferable that irregularities are formed on at least one surface of the pair of rolls 41. Thereby, it is prevented that the coal particle 4 supplied between rolls slides down from the surface of a roll. As a result, the coal particles 4 can be favorably held between the rolls. When the unevenness is formed, the coal particles 4 are also filled in the recess, so that the processing amount per unit time can be increased.

Note that, as a matter of course, the concave shape of the roll surface is transferred as the shape of the molded body. The shape of the concave portion on the surface of the roll is not particularly limited, and may be, for example, a roll pocket (concave portion), a groove, or a combination thereof. It is good also as uneven | corrugated shape not only a recessed part.

An example of a specific shape of the molded body 5 may be a substantially ellipsoid as shown in FIG. For molding, a recess having a shape that halves the molded body 5 may be provided on the surface of the roll 41 (see FIG. 3-3 (a)). A plurality of recesses may be formed side by side on the roll surface.

The gap between the two rolls may be about 1.0 mm. The roll linear pressure may be maintained at 0.5 to 5 t / cm. The number of rotations of the roll and screw feeder may be adjusted so that the physical properties of the molded body 5 to be described later are in a suitable range.

(Example of physical properties of molded body 5)
The molded body 5 preferably has an apparent density of 1.00 g / cm ³ to 1.25 g / cm ³ and a crushing strength of 10 to 800 N. Further, the total moisture of the molded body 5 is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and further preferably 10 to 17 wt%. This total moisture is derived from the total moisture of the coal particles 4. The apparent density can be measured based on “8. Measuring method of density and specific gravity by submerged weighing method” of JIS Z 8807.

The total moisture derived from the coal particles 4 serves as a binder in the molding process. Therefore, by adjusting the total moisture of the molded body to the above range, efficient molding can be performed without adding a binder or a binder separately.

(Example of physical properties of coal particles 4)
The total water content of the coal particles 4 (coal 4) is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and even more preferably 10 to 17 wt%. In the above embodiment, for example, the particle diameter of the coal particles 4 is as fine as 10 to 60 μm. Therefore, the filling rate to the roll pocket in a briquette machine increases at the time of molding.

The moisture contained in the coal 1 is utilized as a binder, and the preferred total moisture range is 5 to 20 wt%, and by specifying the density of the molded body 5, the crushing strength of the molded body 7 is maximized. It becomes possible to adjust to the area. The crushing strength can be measured based on, for example, “3.1 Crushing strength test method” of JIS Z 8841-1993.

(Second crushing step: 10a)
The 2nd crushing process 10a is a process of grind | pulverizing again the molded object 5 obtained at the said process. As the crusher, the same crusher as that used in the first crushing step 10 may be used.

The degree of pulverization here is an example, and the average particle diameter is preferably 0.1 to 1.0 mm, more preferably 0.15 to 0.9 mm, and still more preferably 0.2 to 0.8 mm. There may be.

(Second molding step: 40a)
In the second molding step 40a, for example, molding may be performed using a molding machine similar to the first molding step 40. An example of the physical properties of the molded body 7 obtained by the second molding step 40a is shown below.

(Example of physical properties of molded body 7)
For example, the apparent density of the molded body 7 is preferably 1.20 to 1.4 g / cm ^{3, and} more preferably 1.25 to 1.4 g / cm ³ . The apparent density can be measured based on “8. Measuring method of density and specific gravity by submerged weighing method” of JIS Z 8807, similarly to the molded body 5 described above.

The weight per molded body 7 is preferably 0.2 to 20 g. The total water content of the molded body 7 is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and still more preferably 10 to 17 wt%.

(Sieving step: 70)
The sieving step 70 is a step of sieving the coal molded body 7 that has undergone the above steps. For the sieving operation, for example, a sieve having an opening of about 2.0 to 5.0 mm may be used.

(Heating and curing process: 85)
The heat curing step 85 is a step of curing the coal 8 (molded body) remaining on the sieve in the above step under a predetermined condition.

As curing conditions, coal is heated in a temperature range of, for example, 60 to 120 ° C, preferably 80 to 120 ° C. The heating time is, for example, 15 to 60 minutes, preferably 15 to 55 minutes. Coal may be processed in a sealed state or may be processed in an open state.

The explanation of the sign of the main elements related to the description in Part C is as follows.

40A molding part 40B raw material supply part 41 roll 42 hopper

<< Part D >>
The invention disclosed in Part D relates to a method for producing a coal-molded fuel in which coal is pulverized and then molded.

In Patent Document 1 (Japanese Patent Laid-Open No. 2011-111529), low-grade coal is mixed with oil to form a slurry, and the slurry is heated to dehydrate the coal, and after reducing the water content, pulverized and molded. Thus, a technique for obtaining a solid fuel is disclosed. Patent Document 2 (WO2015 / 098935) discloses a coal-molded fuel obtained by molding coal particles using only coal as a raw material without using a binder or the like, and a method for producing the same.

However, in Patent Document 1, it is necessary to prepare a slurry by mixing with oil, resulting in an increase in cost. Further, when handling the molded solid fuel, a certain level of strength is required. However, Patent Document 1 does not describe the strength. Regarding the coal-molded fuel of Patent Document 2, further improvement has been demanded from the viewpoint of cost reduction and improvement in production efficiency.

The invention of Part D is made in order to solve the above problems, and aims to provide a coal-molded fuel having a desired strength at a low cost.

The main disclosure items in Part D are as follows.

(1) a first crushing step of crushing coal;
A drying step of drying the coal crushed in the first crushing step;
Crushing the coal dried in the drying step to obtain coal particles having an average particle size of 10 to 60 μm;
A first molding step of molding the coal particles having a water content of 5 to 20 wt% to obtain a first molded body;
A second crushing step of crushing the first molded body to generate a second crushed material;
A second molding step of molding the second crushed material again to produce a second molded body having an apparent density of 1.2 to 1.4 g / cm ³ ;
A method for producing a coal-molded fuel having
In the first molding step, a horizontal supply type molding machine is used.

This method can provide a coal-molded fuel having a high molding efficiency and a desired strength at a low cost.

(2) A method for producing a coal-molded fuel according to (1) above,
Supplying a part of the coal particles obtained in the crushing step to the second crushing step without going through the first molding step;
In the second crushing step, the first molded body and a part of the coal particles are mixed and crushed.

According to this method, energy and cost in the manufacturing process can be further reduced.

According to the invention of Part D, a coal-molded fuel having a desired strength can be provided at a low cost. The invention of Part D will be described below.

[Embodiment D1]
FIG. 4-1 shows an example of a process for producing coal-molded fuel as Embodiment D1 of the invention of Part D. The manufacturing process in the embodiment D1 includes a first crushing process 10, a drying process 20, a crushing process 30, a first molding process 40, a second crushing process 10a, and a second molding process 40a. A horizontal supply type molding machine (compactor 400 as an example) is used. As shown in FIG. 4A, a sieving step 70 may be further provided after the second molding step 40a. In addition, although the case where the compactor 400 is used is described in the following description, the horizontal supply type molding machine used in the first molding step is not limited to this.

The method for producing the coal-molded fuel of Embodiment D1 is as follows. After crushing the coal 1 used as a raw material by the 1st crushing process 10 and obtaining the 1st crushing thing 2, it is dried by the drying process 20, The dried coal 3 is grind | pulverized by the crushing process 30, and the coal particle 4 is obtained. . Subsequently, the first molded body 5 is obtained by molding the coal particles 4 with the compactor 400 in the first molding step 40. Furthermore, the 1st molded object 5 is crushed by the 2nd crushing process 10a, the 2nd crushed material 6 is obtained, this is shape | molded by the 2nd shaping | molding process 40a, and the 2nd molded object 7 is obtained. Furthermore, you may obtain the molded object 100 except the pulverized coal with a small particle size through the sieving process 70. FIG. The 2nd molded object 7 or the molded object 100 can be used as a coal molding fuel.

Coal 1 as a raw material is preferably lignite and / or subbituminous coal, more preferably lignite or subbituminous coal having a water content of 25 wt% or more, and more preferably lignite having a water content of 30 wt% or more. Only the coal 1 is used as a raw material, and no binder or additive is used. Use of an additive such as a binder causes a cost increase, but the coal-molded fuel of the invention of Part D uses only coal without adding a binder, so that a desired strength can be obtained at low cost. In the crushing step 10, the coal 1 is crushed with a jaw crusher or a hammer crusher to obtain the first crushed material 2, and the process proceeds to the drying step 20. In the first crushing step 10, the coal 1 has only to be crushed to a size that can be put into a ball mill or the like used in the subsequent crushing step 30, and is not particularly limited, but the maximum particle size of the crushed coal 2 is preferably It is preferably 70 mm or less, more preferably 50 mm or less, still more preferably 20 mm or less, and the average particle diameter is preferably about 1 mm to 20 mm. Note that the moisture content of coal can be measured by the total moisture measurement method for coals described in JIS M 8820-2000 (coal and coke-lot total moisture measurement method). In addition, the average particle size of the crushed coal (first crushed material 2) was measured based on JIS M 8801-2004 “5. Particle size test method”, and the passing sieve mass percentage of each sieve opening was obtained. The particle diameter is such that the mass percentage is 50%.

In the drying step 20, the first crushed material 2 is preferably dried by an indirect dryer to obtain dried coal 3, and the process proceeds to the pulverization step 30. For example, a steam tube dryer may be used as the indirect dryer. Since a large amount of processing is required in the production of solid fuel, it is preferable to use a steam tube dryer that has a large heat transfer area and can be subjected to a large amount of drying treatment.

In the pulverization step 30, the dried coal 3 is pulverized by the pulverizer to obtain the coal particles 4, and the process proceeds to the first molding step 40. The pulverizer is a dry pulverization method or a dry pulverization method. For example, a ball mill or roller mill capable of fine pulverization and suitable for mass processing is used. As in the case of a dryer, a large amount of processing is required in the production of solid fuel, and therefore a pulverizer suitable for mass processing is preferable. In the pulverizing step 30, the average particle diameter of the coal particles 4 is preferably 10 to 60 μm, more preferably 10 to 50 μm, and still more preferably 10 to 30 μm. In this specification, the average particle diameter of the coal particles 4 pulverized in the pulverization step 30 is the median diameter of the particle size distribution obtained by the laser diffraction / scattering method. In order to pulverize to an average diameter of less than 10 μm, a large pulverization power is required, and production by an industrial process is difficult. In this specification, the term “coal particles” means coal particles 4 pulverized by the pulverization step 30 (in the embodiment D2 described later, coal particles 4-1 and 4-2). And

By setting the average particle diameter of the coal particles 4 in the pulverization step 30 within the above range, when the fine coal particles 4 are molded in the molding step 40, the filling rate into the mold (roll pocket) is increased. The desired strength can be obtained by improving the density of the second molded body 7 or the molded body 100 described later.

In addition, since the ball mill and the roller mill can be dried simultaneously with the pulverization, the ball mill and the roller mill may be dried in the pulverization step 30, but the drying capability in the ball mill and the roller mill is insufficient. It is preferable to provide a drying step 20 in advance to ensure the necessary drying capacity.

In the first molding step 40, the coal particles 4 are molded using the compactor 400 as a molding machine to obtain the first molded body 5. The compactor 400 includes a molding unit that molds the raw material and a supply unit that supplies the raw material to the molding unit. The compactor 400 is preferably a horizontal supply system that supplies raw materials in the horizontal direction, and a horizontal supply system roller compactor is more preferable. FIG. 4-3 shows an example of a schematic diagram of a roller compactor that can be suitably used in the first molding step 40. The compactor 400 shown in FIG. 4C is a horizontal supply system, and includes a pair of rolls 41 that are forming means, and a supply means 42 that supplies the coal particles 4 that are raw materials between the pair of rolls 41. The two rolls are arranged one above the other, and the supply means 42 has a raw material supply port (such as a hopper) 43 and a screw feeder that sends the coal particles 4 in the horizontal direction. Each of the pair of rolls 41 has a rotation shaft that is driven by appropriate driving means. The rotation shafts extend in the horizontal direction and are arranged in parallel to each other with an interval in the horizontal direction. The pair of rolls 41 are arranged with a gap. A plate-shaped first molded body formed by pressurizing the coal particles 4 by feeding the coal particles 4 supplied to the gaps between the rolls 41 in the horizontal direction while being pressed by the rotational drive of the rolls 41 in the horizontal direction. 5 is obtained. By using the horizontal supply type compactor 400 in the first molding step 40, the fine coal particles 4 are not easily spilled, and the coal particles 4 can be efficiently supplied to the gaps between the rolls, thereby improving the molding efficiency.

In the vertical feeding and discharging type molding machine, the powder supplied from above is pressurized with a roll and then discharged downward, so that the air caught in the roll escapes upward and the supply of powder becomes discontinuous, There is a possibility that the molding efficiency is lowered. On the other hand, in the horizontal supply / discharge molding machine, the air caught in the roll only escapes above the roll and does not flow backward to the powder side. Therefore, in the first molding step 40, by using a compactor that uses a horizontal supply / discharge method, the molding efficiency can be increased as compared to a vertical supply type molding machine.

If the gap (clearance) between the pair of rolls 41 is too wide, leakage of the coal particles 4 from between the rolls 41 and pressure dispersion are likely to occur, and the density and strength of the first molded body 5 obtained are reduced. This leads to a decrease in yield. Therefore, the gap between the rolls 41 is preferably 3 mm or less. By setting the gap between the rolls 41 to 3 mm or less, a plate-like molded body with sufficient strength can be obtained. The linear pressure between the rolls 41 of the compactor 400 is not particularly limited, but is preferably 0.5 to 3 t / cm.

Further, it is preferable that unevenness is formed on the surface of at least one of the pair of rolls 41. Thereby, it is suppressed that the coal particle 4 supplied between the rolls 41 slips down from the surface of the roll 41, and the coal particle 4 can be hold | maintained favorably between the rolls 41. FIG. Moreover, since the coal particles 4 are filled in the recesses by forming the unevenness, the processing amount per unit time can be increased. In addition, when the surface of the roll 41 has unevenness, the surface shape of the obtained first molded body 5 is transferred to the surface of the roll 41.

The shape of the unevenness formed on the surface of the roll 41 is not particularly limited, and may be, for example, a roll pocket (concave portion), a groove, or a combination thereof.

The size of the first molded body 5 is preferably 5 to 40 mm at the maximum length and width. The apparent density of the first molded body 5 is preferably 1.00 g / cm ³ to 1.25 g / cm ³ . The apparent density can be measured based on “8. Measuring method of density and specific gravity by submerged weighing method” of JIS Z 8807. The water content of the first molded body 5 is 5 to 20 wt%, preferably 8 to 18 wt%, more preferably 10 to 17 wt%. This moisture is derived from the moisture of the coal particles 4.

Since the moisture derived from the coal particles 4 plays a role of a binder in the first molding step 40, the moisture of the first molded body 5 is adjusted to the above range, thereby improving the efficiency without adding a binder or a binder. Molding becomes possible. Note that the moisture content of the coal particles 4 used in the first molding step 40 is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and even more preferably 10 to 17 wt%. Further, the crushing strength of the first molded body 5 (measured based on “3.1 Crushing strength test method” of JIS Z 8841-1993).

Since the particle diameter of the coal particles 4 is as fine as 10 to 60 μm, the filling rate of the roll pockets or grooves of the compactor 400 in the first molding process increases. Thereby, the density of the 1st molded object 5 improves, and contributes to the intensity | strength improvement of the 1st molded object 5. Further, when the moisture contained in the coal 1 is utilized as a binder and the moisture content of the coal particles 4 is preferably set to 5 to 20 wt%, the crushing strength of the first molded body 5 can be adjusted to a maximum region. .

Subsequently, in the second crushing step 10a, the first molded body 5 is crushed by a crusher to obtain a second crushed product 6, and the process proceeds to the second molding step 40a. In addition, although the coal particle 4 which leaked from between rolls without being pressurized with the 1st shaping | molding body 5 is obtained by the 1st shaping | molding process 40, in the 2nd crushing process 10a, this 1st shaping | molding body and the leaked coal particle are obtained. The mixture with 4 may be crushed. The crusher may be the same as that used in the first crushing step 10. The second crushed material 6 has an average diameter of preferably 0.1 to 1.0 mm, more preferably 0.15 to 0.9 mm, and still more preferably 0.2 to 0.8 mm. Moreover, it is preferable that the maximum particle diameter of the 2nd crushing material 6 is below the length of the shorter one of the two vertical and horizontal sides of the particle diameter of the 2nd molded object 7 mentioned later. By adjusting the second crushing step 10a so that the second crushed material 6 is in the range of the average diameter and the maximum particle diameter, a roll pocket in a molding machine such as a briquette machine is formed when the second molded body 7 is molded. The filling rate can be improved.

In the second molding step 40a, the second crushed material 6 is molded by a molding machine to obtain the second molded body 7. The molding machine has a molding means for pressure-molding the raw material and a supply means for supplying the raw material to the molding means. As a molding machine used in the second molding step 40a, for example, a briquette machine or a compactor is preferably used, and a briquette machine is more preferably used. In the 2nd shaping | molding process 40a, it is excellent in economical efficiency by using a briquette machine. The molding machine used in the second molding step 40a may be a vertical supply system or a horizontal supply system, and is preferably a vertical supply system. Note that the types of the molding machine used in the first molding process 40 and the molding machine used in the second molding process 40a may be the same or different in size such as roll pockets.

FIG. 4-4 shows a schematic diagram of a briquette machine 600 that can be suitably used in the second molding step 40a. A briquette machine 600 shown in FIG. 4-4 is of a vertical supply system, and is disposed above the pair of rolls 61 as a forming means and a second material that is a raw material between the pair of rolls 61. Supply means 62 for supplying the crushed material 6. The supply means 62 includes a hopper to which the second crushed material 6 is supplied and a screw feeder that sends the second crushed material 6 in the hopper downward. Each of the pair of rolls 61 has a rotation shaft that is driven by appropriate driving means. The rotation shafts extend in the horizontal direction and are arranged in parallel to each other with an interval in the horizontal direction. The pair of rolls 61 are arranged with a gap. The second crushed material 6 supplied to the gap from above the roll 61 is sent downward while being pressurized by the rotational drive of the roll 61, so that the plate-like second formed by pressurizing the second crushed material 6. A molded body 7 is obtained.

The pair of rolls 61 of the briquette machine 600 may be the same as the roll 41 in the compactor 400 in the first molding step 40 described above, and it is preferable that irregularities are formed by roll pockets and / or grooves. The linear pressure between the rolls 61 of the briquette machine 600 is not particularly limited, but is preferably 5 to 10 t / cm.

The particle diameter of the second molded body 7 is preferably 5 to 40 mm. The apparent density of the second molded body 7 is preferably 1.2 to 1.4 g / cm ³ . The water content of the second molded body 7 is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and still more preferably 10 to 17 wt%.

As described above, in the present embodiment, the first molded body 5 once molded is crushed again in the second crushing step 10a, and is molded again in the second molding step 40a. The first molded body 5 is in a state where the density has already been increased to some extent by the first molding step 40, and the second crushed material 6 also has a similar density. Therefore, it becomes possible to obtain the 2nd molded object 7 which further improved the density rather than the 1st molded object 5 by shape | molding the 1st molded object crushed material 6 again.

Further, the average particle diameter of the pulverized coal particles 4 is 10 to 60 μm, and as it is, the fluidity in the molding machine is poor and it may be difficult to mold. On the other hand, if it is the crushed material 6 of the 1st molded object 5 once molded, since the density is raised to some extent by the 1st shaping | molding process 40, the fluidity | liquidity in a shaping | molding machine is improving, Molding is performed smoothly. As a result, a second molded body 7 having a higher density than that of the first molded body 5 is obtained. By using the second molded body 7 as a coal molded fuel, pulverization during storage and transportation is reduced. Thus, a coal-molded fuel with improved handling properties can be obtained.

As described above, no binder is used in this embodiment. By defining the particle diameter and moisture of the coal particles 4 and the density of the second molded body within the above ranges, the strength of the second molded body is set to a desired value at a low cost without adding a separate binder. It is something that can be done. Moreover, in the manufacturing method of this embodiment, a specific surface area also falls by shape | molding after grind | pulverizing, and the ignition at the time of storage can be reduced. Furthermore, since all known processes are used in the manufacturing process until the second molded body is obtained and no hot water or the like is required, the cost can be reduced.

[Embodiment D2]
FIG. 4-2 shows an example of the manufacturing process of the coal-molded fuel of Embodiment D2. In the embodiment D2, in addition to the manufacturing process of the embodiment D1, a part of the coal particles 4 (coal particles 4-2) obtained in the pulverization process 30 is second crushed without going through the first molding process 40. It has a bypass path (hereinafter also simply referred to as “bypass path”) to be supplied to the step 10a.

In the method for producing a coal-molded fuel according to Embodiment D2, first, the first crushing step 10, the drying step 20, and the crushing step 30 are performed as in Embodiment D1. Among the coal particles obtained in the pulverization step 30, some of the coal particles 4-1 are molded in the first molding step 40 to become the first molded body 5, and some of the coal particles 4-2 are The first crushing step 10a is supplied to the second crushing step 10a without passing through the first molding step 40. In the second crushing step 10a, the mixture of the first molded body 5 and the coal particles 4-2 is crushed to obtain a second crushed product 6, which is molded in the second molding step 40a to be second molded body 7 Get. Furthermore, you may obtain the molded object 100 except the pulverized coal with a small particle size through the sieving process 70. FIG. The 2nd molded object 7 or the molded object 100 can be used as a coal molding fuel.

In the second crushing step 10a of the embodiment D2, the mixture of the first molded body 5 molded from the coal particles 4-1 by the first molding step and the coal particles 4-2 not subjected to the first molding step 40 is crushed. Is done. The first molded body 5 may include coal particles 4-1 leaked from between the rolls without being pressurized by the compactor 400 in the first molding step 40. In the second crushing step 10a, the mixing ratio of the first molded body 5 (including the coal particles 4-1 leaked from between the rolls) and the coal particles 4-2 by the bypass path is not particularly limited, but 90:10 to 60:40 (weight ratio) is preferable, and 90:10 to 70:30 (weight ratio) is more preferable. When the mixing ratio is within this range, the average particle size of the second crushed material 6 is in a suitable range similar to that in the first embodiment (the average size is preferably 0.1 to 1.0 mm, more preferably 0.15 to 0.9 mm, more preferably 0.2 to 0.8 mm). By using the second crushed material 6, the second molding step 40a of the embodiment D2 can be performed with the same power as the second molding step of the embodiment D1, and has a sufficient quality. 7 can be obtained.

By comparing the embodiment D2 (form having a bypass path) with the form not having the bypass path by detailed examination by the inventors of the present application, the apparatus conditions of the second crushing step 10a are adjusted in the embodiment D2. It was found that the second crushed material 6 having an average particle size comparable to that of the form having no bypass path (for example, reducing the number of revolutions of the crusher) can be obtained. Therefore, the power of the crusher in the 2nd crushing process 10a can be reduced by having a bypass path. Furthermore, since some of the coal particles do not pass through the first molding step 40 by having the bypass path, the power of the compactor 400 in the first molding step 40 can be reduced or the size of the compactor 400 can be reduced. it can. Therefore, by having a bypass path, energy and cost can be reduced in the manufacturing process.

The 2nd crushing process 10a of Embodiment D2 can be performed using the same crusher as the 2nd crushing process of Embodiment D1. The second crushed material 6 has an average diameter of preferably 0.1 to 1.0 mm, more preferably 0.15 to 0.9 mm, and still more preferably 0.2 to 0.8 mm. The maximum particle size of the second crushed material 6 is preferably equal to or shorter than the shorter length of the two vertical and horizontal sides of the particle size of the second molded body 7. By adjusting the second crushing step 10a so that the second crushed material 6 is in the range of the average diameter and the maximum particle diameter, a roll pocket in a molding machine such as a briquette machine is formed when the second molded body 7 is molded. The filling rate can be improved. The second molded body 7 can be obtained by performing the second molding step 40a of the embodiment D2 in the same manner as the second molding step 40a of the embodiment D1.

As one aspect of the method for producing coal-molded fuel, a sieve step 70 may be provided after the second molding step 40a of Embodiment D1 or Embodiment D2 to remove coal particles having a small particle size. Fine powder is removed by the sieve, and the second molded bodies 7 are brought into contact with each other on the sieve, so that the weak part is polished and the high part remains. Thereby, the strength of the second molded body 7 is improved.

<Temperature adjustment>
In addition, you may adjust the coal 6 supplied to the 2nd shaping | molding process 40a of Embodiment D1 and Embodiment D2 to predetermined temperature. The predetermined temperature is 50 to 100 ° C., and the quality of the second molded body 7 (improvement in apparent density and decrease in immersion moisture) is improved as compared with supplying the coal 6 to the second molding process at room temperature. Although the principle of quality improvement has not been clarified, it is presumed that the improvement is due to the softening of the raw material and the activation energy of the raw material is reduced.

In the temperature adjustment method, it is only necessary that the coal 6 supplied to the second molding step 40a is at the predetermined temperature, and each device between the crushing step 30 and the second crushing step 10a and a transport device that connects the devices. The temperature may be adjusted directly from the outer periphery of the apparatus. Further, the coal temperature may be adjusted by adjusting the temperature and flow rate of the working gas by using the conveying device as an air transportation system. Further, the temperature of the coal 6 may be adjusted by adjusting the temperature and flow rate of the working gas in the crushing step 30.

When the pneumatic transportation method is used, a working gas having an O ₂ concentration of 10% or less such as combustion exhaust gas may be used for the purpose of reducing dust explosion risk and ignition risk. In addition, when there is a concern that the total moisture of the coal 6 decreases due to the temperature adjustment and deviates from the preferable moisture range at the time of molding, the moisture of the coal 3 discharged from the drying step 20 is increased in anticipation of this. Also good.

The description of the sign of the main elements involved in the description of Part D is as follows.
DESCRIPTION OF SYMBOLS 1 Coal 2 1st crushed material 3 Dried coal 4,4-1, 4-2 Coal particle 5 1st molded object 6 2nd crushed material 7 2nd molded object 10 1st crushing process 20 Drying process 30 Crushing process 40 First molding step 10a Second crushing step 40a Second molding step 70 Sieve step 100 Molded body

<< Part E >>
The invention disclosed in Part E relates to a method for producing a coal molded body obtained by pulverizing and molding coal.

Conventionally, as a technique for obtaining a coal molded body, in Patent Document 2 (WO2015 / 098935), after pulverized coal is molded to obtain a first molded body, the first molded body is crushed and molded again. And a method for obtaining a coal fuel having a desired strength by forming a second molded body. According to Patent Document 2, for molding the first molded body and the second molded body, a pair of rolls having pockets as molds of the molded body formed on the surface, and a screw for supplying a raw material between the pair of rolls, A molding machine (briquette machine) having the following is preferably used. On at least one surface of the pair of rolls, a pocket serving as a mold of a molded body is formed, and the raw material supplied between the rolls by the screw is filled in the pocket and pressurized in the pocket, thereby A molded body is obtained.

As the molding machine, a vertical supply / discharge molding machine is generally used in which raw materials are supplied from vertically above and the molded body is discharged vertically downward. When high-pressure molding of powdery raw material is performed with a vertical feed / discharge type molding machine, air is entrained in the raw material due to stirring of the screw, and the raw material floats. It sometimes became unstable.

An object of the invention of Part E is to provide a method for producing a coal molded body in which a molded body is produced with stable quality in a method for producing a coal molded body using a vertical supply / discharge molding machine.

The main disclosure items of Part E are as follows.

(1) A method for producing a coal molded body molded by a vertical supply / discharge molding machine that molds coal particles supplied from vertically above and discharges the molded coal molded body vertically downward,
The coal particles have an initial volume per unit weight of Vo, a volume at the time of tapping N times as V _N , and a degree of bulk reduction as C = (Vo−V _N ) / Vo.
Formula (1): N / C = (1 / ab) + (1 / a) N
In
Condition (1): a ≦ 0.29
Condition (2): 20 ≦ 1 / b ≦ 60
A method for producing a coal molding characterized by satisfying any of the above.

According to this manufacturing method, a molded coal can be manufactured with stable quality.

(2) In the method for producing a molded coal according to (1) above,
A first crushing step of crushing coal;
A drying step of drying the coal crushed in the first crushing step;
Crushing the coal dried in the drying step to obtain pulverized coal;
A first molding step of molding the pulverized coal to obtain a first molded body;
A second crushing step of crushing the first molded body to generate a lump,
A second molding step for re-molding the mass and generating a second molded body;
Have
The lump is an aggregate of the pulverized coal, corresponding to the coal particles,
In the second molding step, the vertical supply / discharge molding machine is applied,
A method for producing a coal molding characterized by the above.

In the manufacturing method having the above steps, it is more effective to apply the vertical supply / discharge molding machine described in (1).

(3) In the method for producing a molded coal according to (2) above,
The pulverized coal has an average particle size of 10 to 60 μm and a total water content of 5 to 20 wt%.
The apparent density of the second molded body is 1.2 to 1.4 g / cm ³ ;
A method for producing a coal molding characterized by the above.

According to this production method, the second molded body having the above apparent density can be produced using the pulverized coal described above.

According to the invention of Part E, a coal molding can be manufactured with stable quality. The invention of Part D will be described below.

Referring to FIG. 5-1, there is shown a process for producing a molded coal according to an embodiment of the invention of Part E. In this embodiment, the manufacturing process of the coal molding includes a first crushing process 10, a drying process 20, a crushing process 30, a first molding process 40, a second crushing process 10a, a second molding process 40a, and a sieving process 70. ing. The coal 1 that is a raw material is crushed in the first crushing step 10 to be crushed material 2, then dried in the drying step 20 to be dried material 3, and the dried material 3 is further pulverized in the pulverizing step 30. Charcoal 4 is obtained. The pulverized coal 4 is molded as the first molded body 5 in the first molding step 40 and then crushed again in the second crushing step 10a, whereby the second crushed material 6 that is a lump corresponding to coal particles is obtained. can get. Since the obtained lump is obtained by crushing the first molded body 5 obtained by molding the pulverized coal 4, it can be referred to as an aggregate of the pulverized coal 4. Thereafter, in the second molding step 40a, the second molded body 7 is obtained from the second crushed material 6, and the powder is removed from the second molded body 7 by the sieving step 70, whereby the coal molded body 100 is obtained. The obtained coal molding 100 can be used suitably as a coal molding fuel.

Note that the sieving step 70 is not an essential step in the invention of Part E, and the second molded body 7 obtained in the second molding step 40a can be the coal molded body 100.

As the coal 1 used as a raw material, lignite or subbituminous coal having a water content of 25 wt% or more can be used. Preferably, lignite with a water content of 30 wt% or more can be used. In a series of manufacturing steps of a coal molding, only coal is used as a raw material, and additives such as a binder are not used. Use of an additive such as a binder increases the cost. However, in this embodiment, since only coal is used without adding a binder, a molded coal can be obtained at low cost.

In the first crushing step 10, the coal 1 is crushed using an appropriate crushing means such as a jaw crusher or a hammer crusher to obtain a first crushed material 2 that is crushed coal. In the 1st crushing process 10, although coal should just be crushed to the magnitude | size which can be thrown into grinding | pulverization means, such as a ball mill used by the subsequent crushing process 30, it does not specifically limit, The magnitude | size of the 1st crushing thing 2 is the maximum particle diameter. However, it is preferably 70 mm or less, more preferably 50 mm or less, still more preferably 20 mm or less, and particularly preferably the average particle diameter is 1 mm to 20 mm. Here, the average particle diameter of the coal crushed in the first crushing step 10 is measured based on “5. Particle size test method” of JIS M 8801-4, and the passing sieve mass percentage of each sieve opening is obtained. The particle diameter at which the passing sieve mass percentage is 50% is defined as the average particle diameter.

The obtained first crushed material 2 is supplied to the drying step 20. In the drying step 20, the first crushed material 2 is dried using an appropriate dryer such as an indirect dryer to obtain a dried product 3. As the indirect dryer, for example, a steam tube dryer can be used. In the production of solid fuel in which the coal molded body 100 is preferably used, a large amount of processing is required. Therefore, the steam tube dryer having a large heat transfer area and capable of a large amount of drying processing is suitable as a dryer used in the drying step 20. is there.

The obtained dried product 3 is supplied to the pulverization step 30. In the pulverization step 30, the dried product 3 is pulverized by an appropriate pulverizer to obtain pulverized coal 4. As the pulverizer, a dry pulverizer or a dry pulverizer pulverizer can be used. Among them, a ball mill or a roller mill that can finely pulverize and is suitable for mass processing can be preferably used. This is because, in the production of solid fuel, a large amount of processing is required in the pulverization step 30 as in the drying step 20.

The average particle size of the pulverized coal 4 obtained in the pulverizing step 30 is 10 to 60 μm, preferably 10 to 50 μm, more preferably 10 to 30 μm. The average particle diameter of the pulverized coal 4 is given by the median diameter of the particle size distribution obtained by the laser diffraction / scattering method. In the present specification, “pulverized coal” means the pulverized coal 4 obtained in the pulverization step 30.

By setting the average particle diameter of the pulverized coal 4 obtained in the pulverization step 30 within the above range, the filling rate of the mold (for example, roll pocket) is increased when the fine pulverized coal 4 is molded in the first molding step 40. And the desired intensity | strength can be obtained by improving the density of the coal molding 100 mentioned later.

In addition, since the ball mill and the roller mill can be dried simultaneously with the pulverization, the ball mill and the roller mill can be dried in the pulverization step 30. However, since it is difficult to sufficiently dry the crushed material 2 obtained in the first crushing step 10 with the drying capability of the ball mill and the roller mill, in this embodiment, the drying step 20 is provided before the crushing step 30. A sufficiently dry pulverized coal 4 is obtained.

The obtained pulverized coal 4 is supplied to the first molding step 40. The first molding step 40 includes molding the pulverized coal 4 into a plate shape using a molding machine. The molding machine has a molding means for pressure-molding the raw material (in this embodiment, pulverized coal 4) and a supply means for supplying the raw material to the molding means. As such a molding machine, for example, a briquette machine can be used.

FIG. 5-2 shows a schematic diagram of a briquette machine that can be suitably used in the first molding step 40. The briquette machine shown in FIG. 5B is a vertical supply / discharge briquette machine that molds the pulverized coal 4 supplied from vertically above and discharges the molded first molded body 5 to the vertically lower side. The briquette machine has a pair of rolls 41 that are molding means, and a supply means 42 that is disposed above the pair of rolls 41 and supplies pulverized coal 4 that is a raw material between the pair of rolls 41. The supply means 42 includes a hopper to which the pulverized coal 4 is supplied, a screw feeder that sends the pulverized coal 4 in the hopper downward, and the like. Each of the pair of rolls 41 has a rotation shaft that is driven by appropriate driving means. The rotating shaft extends in the horizontal direction, and the pair of rolls 41 are arranged in parallel to each other with a gap in the horizontal direction. The pulverized coal 4 supplied from above into the gap of the roll 41 is sent downward while being pressurized by the rotational drive of the roll 41, whereby the first molded body 5 in which the pulverized coal 4 is pressure-molded is obtained.

If the gap (clearance) between the pair of rolls 41 is too wide, leakage of the pulverized coal 4 from the rolls 41 and pressure dispersion are likely to occur, and the density and strength of the first molded body 5 to be obtained are reduced. This leads to a decrease in rate. Therefore, the gap between the rolls 41 is preferably 3 mm or less. By setting the gap between the rolls 41 to 3 mm or less, it is possible to obtain the plate-like first molded body 5 in which sufficient strength is ensured.

Further, it is preferable that unevenness is formed on the surface of at least one of the pair of rolls 41. Thereby, it is suppressed that the pulverized coal 4 supplied between the rolls 41 slides down from the surface of the roll 41, and the pulverized coal 4 can be held between the rolls 41 and pressurized. Moreover, since the pulverized coal 4 is filled in the recesses by forming the irregularities, the processing amount per unit time can be increased. When the surface of the roll 41 has irregularities, the irregularities on the surface of the roll 41 are transferred to the surface shape of the obtained first molded body 5.

The shape of the unevenness formed on the surface of the roll 41 is not particularly limited, and may be, for example, a roll pocket (concave portion), a groove, or a combination thereof.

When the unevenness is formed by roll pockets, the shape of the roll pocket can be arbitrary. An example of the shape of the roll pocket is shown in FIGS. 5-3A and 5-3B. The illustrated example is an example in which a substantially elliptical roll pocket is formed only on one side of the roll, whereby a first molded body 5 having a convex part of a one-sided plane almond shape is obtained. The roll pocket may be formed on the rolls on both sides, and the planar shape of the roll pocket may be a rounded polygon, a circle, an oval, or the like. The dimensions (vertical length a, horizontal length b, depth c) of each part of the roll pocket, and the gap d between the rolls 41 (thickness formed at the surface portion of the first molded body 5 where the irregularities are not formed. Table E1 shows preferred dimension ranges of

Also, when the irregularities are formed by grooves, the width, depth, arrangement, etc. of the grooves can be arbitrary. For example, as shown in FIG. 5-4, a plurality of grooves parallel to the axial direction A of the roll 41 and a plurality of grooves parallel to the circumferential direction B may be arranged in a lattice pattern. In addition to this, a plurality of grooves parallel to the axial direction A of the roll 41 and a plurality of grooves oblique to the axial direction A and the circumferential direction B of the roll 41 are arranged to intersect. Etc. are also possible. The width of the groove (the length in the direction perpendicular to the length direction of the groove on the surface of the roll 41) is preferably 0.5 to 5 mm. The depth of the groove is preferably 0.5 to 2 mm.

The first molded body 5 obtained in the first molding step 40 preferably has an apparent density of 1.00 g / cm ³ to 1.25 g / cm ³ and a crushing strength of 10 to 800 N. Further, the total water content of the pulverized coal 4 used in the first molding step 40 is preferably 5 to 20 wt%, more preferably 8 to 18 wt%, and further preferably 10 to 17 wt%.

In the first molding step 40, a horizontal supply / discharge molding machine, for example, a compactor, which supplies raw materials in the horizontal direction and discharges the molded first molded body 5 in the horizontal direction can also be used. Similarly to the vertical supply / discharge type briquette machine, the horizontal supply / discharge type compactor also has a forming means for forming the raw material and a supply means for supplying the raw material to the forming means. The molding means can have, for example, a pair of rolls, and the pair of rolls are arranged so that the raw material is pressure-molded between the rolls as the roll rotates as the raw material is supplied between the rolls. Is done. However, in a horizontal supply / discharge compactor, two rolls are arranged up and down. By using a horizontal supply and discharge type compactor in the first molding step 40, the yield of the first molded body 5 obtained, that is, the molding efficiency can be improved.

The first molded body 5 obtained in the first molding step 40 is supplied to the second crushing step 10a. In the 2nd crushing process 10a, the 1st molded object 5 is crushed with a crusher, and the 2nd crushing thing 6 which is a lump is obtained. The second crushed material 6 is an aggregate of pulverized coal, and this pulverized coal corresponds to the pulverized coal 4 obtained in the pulverization step 30. Therefore, the pulverized coal preferably has an average particle diameter of 10 to 60 μm, and preferably has a total water content of 5 to 20 wt%.

The crusher used in the second crushing step 10a may be the same as that used in the first crushing step 10. The second crushed material 6 preferably has an average particle size of 0.1 to 1.0 mm, more preferably 0.15 to 0.9 mm, and still more preferably 0.2 to 0.8 mm. Moreover, it is preferable that the maximum particle diameter of the 2nd crushing material 6 is below the length of the shorter one among the two sides of the vertical and horizontal sides of the particle diameter of the below-mentioned 2nd molded object 7. FIG. By adjusting the second crushing step 10a so that the second crushed material 6 is in the above average particle size range and the maximum particle size range, the second crushing step 6a to the mold in the molding machine at the time of molding in the second molding step 10a. The filling rate of the crushed material 6 can be improved. The resulting second molded body 7 has superior quality (crushing strength and apparent density) compared to the first molded body 5. In addition, when using a briquette machine as a molding machine in the 1st shaping | molding process 40 and the 2nd shaping | molding process 40a, the size (particle diameter) of the roll pocket formed in a roll surface is the 1st shaping | molding process 40 and the 2nd shaping | molding process 40a. May or may not be the same.

In the second molding step 40a, the second crushed material 6 is molded by the molding machine to obtain the second molded body 7, but the second molded body 7 falls from between the rolls without being pressure-molded between the rolls. The 2nd crushed material 6 and the 2nd crushed material 6 which fell out from the 2nd molded object 7 without fully press-molding may also be included. These second crushed materials 6 are preferably removed by a sieving step 70 provided after the second molding step 40a, whereby a coal molded body 100 is obtained. In the sieving step 70, a vibration sieving machine can be used. As the vibrating sieve, a circular sieve, a trommel sieve, or the like can be used, and among them, those capable of continuous / mass processing are preferable.

As the molding machine used in the second molding process 40a, a vertical supply / discharge molding machine, such as a briquette machine, can be used as in the first molding process 40.

Generally, in a vertical supply / discharge molding machine having a screw-type supply means, air is entrained in the second crushed material 6 due to the stirring of the second crushed material 6 as a raw material by a screw. The amount of air entrained in the second crushed material 6 tends to increase as the screw rotation speed increases. When the second crushed material 6 accompanied with air is supplied between the rolls, air is pushed out from the second crushed material 6 as the second crushed material 6 is compressed by the roll. Although the pushed air flows upward, the supply direction of the second crushed material 6 is downward, so that a phenomenon such as flushing of the second crushed material 6 occurs when the amount of air generated is large. Thereby, the continuous supply of the raw material between the rolls is not sufficiently performed, and the second molded body 7 has a stable quality (crushing strength and apparent density) such that the second molded body 7 is intermittently discharged. It becomes difficult to be molded.

To avoid this,
(I) increase the density of the second crushed material 6 itself (to increase the weight), and (ii) increase the filling rate of the second crushed material 6 between the rolls,
And so on. However, in the case of (i), if the density of the second crushed material 6 itself is too high, the quality of the obtained second molded body 7 is affected. In the case of (ii), there is a method of increasing the filling rate by reducing the particle size of the second crushed material 6, but by reducing the particle size of the second crushed material 6, the second crushed material 6 Flushing is likely to occur, which may be counterproductive.

Therefore, as a result of repeated studies by the present inventors, it was found that when the fluidity of the raw material was expressed by a specific index, the index correlated with the stable operation of the vertical supply / discharge molding machine. That is, when the initial volume per unit weight of the second crushed material 6 is Vo, the volume after tapping N times is V _N, and the degree of bulk reduction after tapping is C = (Vo−V _N ) / Vo,
Formula (1): N / C = (1 / ab) + (1 / a) N
In
Condition (1): a ≦ 0.29
Condition (2): 20 ≦ 1 / b ≦ 60
Is to satisfy both. By adjusting the characteristics of the raw material supplied to the vertical supply / discharge molding machine so as to satisfy these conditions (1) and (2), the instability of the raw material due to the air flow generated in the molding by the molding machine Therefore, efficient molding can be performed with stable operation of the molding machine.

The above equation (1) is called Kawakita's equation and is known to accurately indicate the compression / flow characteristics of the powder. In Kawakita's equation, “a” is a liquidity index, and the smaller this value, the better the liquidity. “1 / b” is an adhesion index, and the smaller the value, the weaker the adhesion.

Here, in the invention of Part E, whether or not the molding machine is stably operated is determined as follows.

The state in which the operation is stable means a state where a certain amount of raw material is molded as a molded body of a certain quality. The quality (crushing strength, apparent density) of the molded product discharged from the molding machine depends on the roll kW that is the output of the drive motor that rotates the roll. If the roll kW can be maintained constant, the molded product of a constant quality Is discharged. Therefore, if the roll kW is kept constant at a constant roll speed, it is determined that the molding machine is stably operated. When the roll kW is low, the quality of the molded body is deteriorated, or the ratio of raw materials left unmolded due to insufficient compression force is increased. Here, “the roll rotation speed and the roll kW are“ constant ”” means that these fluctuations are within a range of ± 15% with respect to the reference value (set value).

In actual operation, the physical properties (particle size distribution, apparent density, strength, etc.) and bulk density of the supplied raw material may vary. This is because the coal 1 that is the raw material supplied to the molding machine is a natural product, and therefore physical properties such as particle size distribution, apparent density, and strength vary depending on the mining site. Variations in the physical properties of the raw material cause variations in the roll kW of the molding machine. Moreover, the fluctuation | variation of the bulk density of the raw material supplied to a molding machine also becomes a factor of fluctuation | variation of the roll kW. In this case, the roll kW can be kept constant by controlling the screw rotation speed and adjusting the supply amount of the raw material between the rolls. Even if there is a change in the physical properties of the supplied raw material, if a constant roll kW can be maintained, a fixed amount of a molded product of a constant quality is discharged, and as a result, it can be said that the operation is stable.

Depending on the physical properties of the raw material, the roll kW may not be kept constant even if the screw speed is controlled. In this case, it is determined that the operation of the molding machine is unstable.

The particle diameter of the second molded body 7 obtained in the second molding step 40a is preferably 5 to 40 mm. The second molded body 7 preferably has an apparent density of 1.2 to 1.4 g / cm ³ and a bulk density of 0.4 to 0.6. The weight of the second molded body 7 is preferably 0.2 to 20. The total water content of the second molded body 7 is 5 to 20 wt%, preferably 8 to 18 wt%, more preferably 10 to 17 wt%. The moisture of the coal molded body 100 is derived from the moisture of the second crushed material 6 which is a raw material in the second molding step 40a.

Here, the apparent density is a value measured based on “8. Method for measuring density and specific gravity by submerged weighing method” of JIS Z 8807. The bulk density is a value calculated by the following formula from the weight of the filled sample and the volume of the container after the sample is ground and filled into a container of about 2 to 5 L whose volume is known. In addition, the method of throwing into the container differs between rough filling and dense filling. In the rough filling, when the sample was put into the container, the sample was filled so as not to be compacted as much as possible, and in the close filling, the container was filled while tapping. The number of tapping was 10 times.
Bulk density = Mass of filled sample ÷ Container volume

The water content is a value measured based on “Measurement method of total water content of coals” of JIS M 8820-0. Moreover, it is preferable that the coal molding 100 has a hard glove grindability index (HGI) of 40 or more.

As described above, in this embodiment, the first molded body 5 once molded is crushed again in the second crushing step 10a, and is molded again in the second molding step 40a. The first molded body 5 is in a state in which the density has already been increased to some extent in the first molding step 40, and the second crushed material 6 also has a similar density. Therefore, by molding the second crushed material 6 again, it is possible to obtain the second molded body 7 having a further improved density than the first molded body 5.

Further, the average particle diameter of the pulverized coal 4 pulverized in the pulverizing step 30 is 10 to 60 μm, and as it is, the fluidity in the briquette machine is poor and it may be difficult to mold. On the other hand, if it is a crushed material of the first molded body 5 once molded, the density is increased to some extent by the first molding step 40, so that the fluidity in the briquette machine is improved, and the second molding step 40a Molding is performed smoothly. Thereby, the 2nd molded object 7 whose density is higher than the 1st molded object 5 will be obtained, and by making this 2nd molded object 7 into the coal molded object 100, the powdering at the time of storage and conveyance is carried out. Furthermore, it is reduced, handling property can be improved, and it becomes suitable as a coal molding fuel.

In addition, you may provide the water | moisture-content adjustment process which adjusts the total water | moisture content of the coal molding 100 finally obtained. In the case where the moisture adjusting step has the sieving step 70, the moisture adjusting step is preferably provided after the sieving step 70. By the moisture adjustment step, dust generation and spontaneous heat generation of the coal molded body 100 can be prevented.

In the moisture adjustment step, a belt conveyor is disposed, and watering equipment including a water supply pump and a spray nozzle is disposed on the belt conveyor, and the coal molding 100 is conveyed by the belt conveyor. There is a method in which the moisture of the coal molded body 100 falls within a suitable range with respect to the coal molded body 100 that has passed through the sieving process 70. Further, after the coal molding 100 that has undergone the sieving process 70 is erected (stacked in a mountain shape to form a pile), the water of the erected coal molding 100 is preferably used by a watering facility including a water supply pump and a sprinkler. A method of adjusting the range may be used.

The moisture after the moisture adjustment step of the coal molded body 100 is preferably 10 to 30 wt%, more preferably 10 wt% or more and less than 25 wt%.

The explanation of the sign of the main elements related to the description in Part E is as follows.

DESCRIPTION OF SYMBOLS 1 Coal 2 1st crushed material 3 Dry material 4 Pulverized coal 5 1st molded object 6 2nd crushed material 7 2nd molded object 10 1st crushing process 20 Drying process 30 Crushing process 40 1st shaping | molding process 10a 2nd crushing process 40a Second molding process 70 Sieving process 100 Molded body

<< Part F >>
The invention disclosed in Part F relates to a method for producing a coal molded fuel obtained by molding pulverized coal.

Conventionally, as a technique for obtaining a coal-molded fuel, in Patent Document 2 (WO2015 / 098935), after pulverized coal is molded to obtain a first molded body, the first molded body is crushed and molded again. And a method for obtaining a coal fuel having a desired strength by forming a second molded body.

According to the technique described in Patent Document 2, a coal-molded fuel having a desired strength can be obtained at a low cost. However, Patent Document 2 does not describe improvement in quality of coal fuel by temperature during molding and heating.

The invention of Part F aims to provide a method for producing a coal-molded fuel in which high-quality coal fuel is obtained by molding coal particles at a temperature higher than room temperature.

The main disclosure items in Part F are as follows. Note that the reference does not limit the disclosed content.

(1) A method for producing a coal-molded fuel 200, wherein the coal particles 4 are molded at a temperature of 50 to 150 ° C.

By molding the coal particles 4 at the above-described temperature, the strength is improved and / or the increase in total moisture is suppressed, and as a result, a high-quality coal-molded fuel can be obtained.

(2) In the method for producing the coal-molded fuel 200 according to (1) above,
A method for producing a charcoal-molded fuel 200, characterized by using a rotary molding machine equipped with a pair of rolls and molding at a linear pressure of 5 to 15 t / cm.

A rotary molding machine can be used for molding the coal particles 4, and in that case, a high quality coal molded fuel can be produced by setting the linear pressure within the above range.

(3) In the method for producing the coal-molded fuel 200 according to (2) above,
The molded coal fuel 200 has a crushing strength per unit mass represented by a value obtained by dividing the crushing strength measured by the test method defined in JIS Z 8841 by the mass of the coal molded fuel 200, which is 100 N / g. The method for producing coal-molded fuel 200, which is as described above.

In addition, when a rotary molding machine is used, a high-strength coal molding fuel 200 can be manufactured by setting the linear pressure within the above range.

(4) In the method for producing the coal-molded fuel 200 according to (1) above,
A method for producing coal-molded fuel 200, characterized in that the molding is performed at a surface pressure of 0.5 to 2.5 t / cm ² using a piston-type compression molding machine.

A piston-type compression molding machine can be used for molding the coal particles 4, and in that case, a high-quality coal-molded fuel can be produced by setting the surface pressure within the above range.

(5) In the method for producing the coal-molded fuel 200 according to (4) above,
A method for producing a coal-molded fuel 200, characterized in that the total moisture of the coal-molded fuel 200 when immersed in water for 72 hours or more after standing at room temperature for 24 hours after molding is 30% or less.

Moreover, when using a piston type compression molding machine, the coal molding fuel 200 in which moisture is suppressed can be manufactured by setting the surface pressure within the above range.

According to the invention of Part F, high-quality coal-molded fuel that improves strength, improves apparent density, and / or suppresses moisture rise during outdoor storage by molding coal particles at a temperature higher than room temperature. Can be obtained. Hereinafter, an embodiment of the invention of Part F will be described.

[Embodiment F1]
Referring to FIG. 6-1, a process for producing a coal-molded fuel according to Embodiment F1 of the Part F invention is shown. In Embodiment F1, the process for producing coal-molded fuel includes a crushing process 10, a crushing process 20, a drying process 30, a molding process 40, and a sieving process 70. After crushing the coal 1 as a raw material, crushing and drying are performed. As a result, coal particles 4 are obtained. The coal particles 4 are molded by a molding machine to obtain a molded body 5. The molded body 5 contains coal powder such as unmolded coal particles 4, and the coal molded fuel 200 is obtained by removing the coal powder from the molded body 5.

As the coal 1 used as a raw material, lignite or subbituminous coal having a water content of 25 wt% or more can be used. Preferably, lignite with a water content of 30 wt% or more can be used. The water content is a value measured based on the “total water measurement method for coals” described in “Coal and cokes—a total water measurement method for lots” of JIS M 8820-2000. In a series of manufacturing processes of coal-molded fuel, only coal is used as a raw material, and additives such as a binder are not used. Use of an additive such as a binder increases the cost. However, in this embodiment, since only coal is used without adding a binder, a molded coal can be obtained at low cost.

In the crushing step 10, the coal 1 is crushed by using an appropriate crushing means such as a jaw crusher or a hammark crusher to obtain a crushed coal 2 which is crushed coal. In the crushing step 10, the coal may be crushed to a size that can be charged into a pulverizing means such as a ball mill used in the subsequent pulverizing step 20. The size of the crushed material 2 is not particularly limited, but the maximum particle size is preferably It is 70 mm or less, More preferably, it is 50 mm or less, More preferably, it is 20 mm or less. The average particle size of the crushed coal 2 is preferably 1 mm to 20 mm. Here, the average particle diameter of the pulverized coal 2 obtained by the crushing step 10 is measured based on “5. Particle size test method” of JIS M 8801-4, and the passing sieve mass percentage of each sieve opening is obtained. The particle diameter at which the passing sieve mass percentage is 50% is defined as the average particle diameter.

The obtained crushed coal 2 is supplied to the pulverization step 20. In the pulverization step 20, the pulverized coal 2 is pulverized by an appropriate pulverizer to obtain the pulverized coal 3. As the pulverizer, a dry pulverizer or a dry pulverizer pulverizer can be used. Among them, a ball mill or a roller mill that can finely pulverize and is suitable for mass processing can be preferably used. This is because, in the production of solid fuel, as in the drying step 30, a large amount of processing is required in the pulverizing step 40. Moreover, a pellet mill can also be used as a grinder. The average particle size of the pulverized coal 3 obtained in the pulverization step 20 is 10 to 60 μm, preferably 10 to 50 μm, more preferably 10 to 30 μm.

The obtained pulverized coal 3 is supplied to the drying step 30. In the drying step 30, the dried coal particles 4 are obtained by drying the pulverized coal 3 using an appropriate dryer such as an indirect dryer. As the indirect dryer, for example, a steam tube dryer can be used. In the production of solid fuel in which the coal-molded fuel 200 is suitably used, a large amount of processing is required. Therefore, the steam tube dryer having a large heat transfer area and capable of performing a large amount of drying processing is suitable as a dryer used in the drying step 30. is there. A blower dryer can also be used as the dryer.

The order of the grinding step 20 and the drying step 30 may be reversed. That is, after the crushing step 10, the drying step 30 is performed to obtain the dry coal 3 ′, and the obtained dry coal 3 ′ can be pulverized in the crushing step 20. Regardless of which of the pulverization step 20 and the drying step 30 is performed first, the dried coal particles 4 are obtained through the pulverization step 20 and the drying step 30.

The average particle diameter of the obtained coal particles 4 corresponds to that obtained by the crushing step 20. That is, the average particle diameter of the coal particles 4 is 10 to 60 μm, preferably 10 to 50 μm, more preferably 10 to 30 μm. The average particle diameter of the coal particles 4 is given by the median diameter of the particle size distribution obtained by the laser diffraction / scattering method. In the present specification, the “coal particles” mean the coal particles 4 obtained through the pulverization step 20 and the drying step 30.

By setting the average particle diameter of the coal particles 4 in the above range, the filling rate into the mold increases when the fine coal particles 4 are molded in the molding step 40, and the density of the coal-molded fuel 200 described later is improved. Desired strength can be obtained.

In addition, since the ball mill and the roller mill can be dried simultaneously with the pulverization, the ball mill or the roller mill can be dried in the pulverization step 20. However, it is difficult to sufficiently dry the crushed coal 2 obtained in the crushing process with the drying capability of the ball mill and the roller mill. Therefore, in this embodiment, the drying step 30 is provided after the crushing step 10 and before or after the crushing step 20 to obtain the sufficiently dried coal particles 4.

The obtained coal particles 4 are supplied to the molding process 40. The molding process 40 includes molding the coal particles 4 with a molding machine. In the molding step 40, the coal particles 4 are molded at a temperature higher than room temperature, specifically 50 to 150 ° C. The molding temperature in the molding process 40 is not the set temperature of the molding machine but the temperature of the coal particles 4 themselves during the molding process.

Therefore, when the coal particles 4 supplied to the molding machine are out of the above temperature range, the molding machine uses a heater or a cooler so that the temperature of the coal particles 4 being molded is within the above temperature range. Can be included. Alternatively, between the step immediately before the molding step 40 (the crushing step 20 or the drying step 30) and the molding step 40 so that the temperature of the coal particles 4 supplied to the molding step 40 is within the above temperature range, A temperature adjusting function for adjusting the temperature of the coal particles 4 may be provided. For example, in the pulverization step 20, the coal being processed may be heated by friction, pressurization, or the like depending on the pulverization conditions, and the drying step 30 may be heated. Therefore, the temperature adjustment function is performed so that the temperature of the coal particles 4 supplied to the molding process 40 falls within the above temperature range according to the temperature of the coal particles 4 discharged from the process immediately before the molding process 40. It may be any function that can heat or cool the particles 4.

As the molding machine in the molding step 40, any molding machine such as a rotary molding machine and a piston compression molding machine can be used. Hereinafter, a molding machine that can be used in the molding step 40 will be described with reference to the drawings.

FIG. 6-2 shows a schematic diagram of a briquette machine as an example of a rotary molding machine that can be used in the molding process 40. The briquette machine shown in FIG. 6B is a raw material vertical supply type briquette machine, which is disposed above a pair of rolls 41 and a pair of rolls 41 as a forming means. Supply means 42 for supplying a certain coal particle 4. The supply means 42 includes a hopper to which the coal particles 4 are supplied, a screw feeder that sends the coal particles 4 in the hopper downward, and the like. Each of the pair of rolls 41 has a rotation shaft that is driven by appropriate driving means. The rotation shafts extend in the horizontal direction and are arranged in parallel to each other with an interval in the horizontal direction. The pair of rolls 41 are arranged with a gap. By feeding the coal particles 4 supplied to the gap from above the roll 41 downward while being pressurized by the rotational drive of the roll 41, the plate-shaped molded body formed by the pressurization of the coal particles 4 and the pressure are applied. The molded body 5 including the coal particles 4 leaking from between the rolls 41 is obtained.

If the gap (clearance) between the pair of rolls 41 is too wide, leakage of the coal particles 4 from between the rolls 41 and pressure dispersion are likely to occur, and the density and strength of the finally obtained coal molded fuel 200 are reduced. As well as a decrease in yield. Therefore, the gap between the rolls 41 is preferably 3 mm or less. By setting the gap between the rolls 41 to 3 mm or less, a plate-like molded body with sufficient strength can be obtained. The linear pressure between the rolls 41 is not particularly limited, but is preferably 5 to 15 t / cm.

It is preferable that unevenness is formed on the surface of at least one of the pair of rolls 41. Thereby, it is suppressed that the coal particle 4 supplied between the rolls 41 slips down from the surface of the roll 41, and the coal particle 4 can be hold | maintained favorably between the rolls 41. FIG. Moreover, since the coal particles 4 are filled in the recesses by forming the unevenness, the processing amount per unit time can be increased. In addition, when the surface of the roll 41 has unevenness, the surface unevenness of the surface of the roll 41 is transferred as the surface shape of the obtained coal-molded fuel 200.

The shape of the unevenness formed on the surface of the roll 41 is not particularly limited, and may be, for example, a roll pocket (concave portion), a groove, or a combination thereof.

When the irregularities are formed by roll pockets, the shape of the roll pocket can be arbitrary. An example of the roll pocket is shown in FIGS. 6-2A and 2B. FIGS. 6-2A and 2B are examples in which roll pockets having rounded square openings are formed on the rolls on both sides, whereby a rounded pillow-shaped coal molded fuel 200 is obtained. The preferred dimension range (design value) of each part of the illustrated roll pocket is:
a: 5 to 40 mm
b: 5 to 40 mm
c: 1-15mm
d: 1 mm
It is.

Also, when the irregularities are formed by grooves, the width, depth, arrangement, etc. of the grooves can be arbitrary. An example of the groove arrangement is shown in FIG. 6-2C. In the example shown in FIG. 6-2C, a plurality of grooves parallel to the axial direction A of the roll 41 are arranged. The width of the groove (the length in the direction perpendicular to the length direction of the groove on the surface of the roll 41) is preferably 0.5 to 5 mm. The depth of the groove is preferably 0.5 to 2 mm.

FIG. 6-3 shows a schematic diagram of a compactor as another example of a rotary molding machine that can be used in the molding process 40. The compactor shown in FIG. 6-3 is a horizontal supply system, and includes a pair of rolls 41 that are molding means and a supply means 45 that supplies coal particles 4 that are raw materials between the pair of rolls 41. The two rolls 41 are arranged one above the other, and the supply means 45 has a raw material supply port (such as a hopper) 46 and a screw feeder that sends the coal particles 4 in the horizontal direction. Each of the pair of rolls 41 has a rotation shaft that is driven by appropriate driving means. The rotation shafts extend in the horizontal direction and are arranged in parallel to each other with a gap in the vertical direction. A plate-like molded body 5 formed by pressurizing the coal particles 4 by feeding the coal particles 4 supplied to the gaps between the rolls of the roll 41 from the horizontal direction in a horizontal direction while pressurizing them by the rotational drive of the rolls 41. can get. By using a horizontal supply type rotary molding machine in the molding step 40, the fine coal particles 4 are not easily spilled, and the coal particles 4 can be efficiently supplied to the gaps between the rolls, thereby improving the molding efficiency.

In the vertical feeding and discharging type molding machine, the powder supplied from above is pressurized with a roll and then discharged downward, so that the air caught in the roll escapes upward and the supply of powder becomes discontinuous, There is a possibility that the molding efficiency is lowered. On the other hand, in the horizontal supply / discharge molding machine, the air caught in the roll only escapes above the roll and does not flow backward to the powder side. Therefore, by using a compactor with a horizontal supply / discharge system, the molding efficiency can be increased as compared with a vertical supply type molding machine.

The gap (clearance) between the pair of rolls 41, the linear pressure, and the surface structure of the roll 41 (unevenness such as grooves) are the same as in the case of the above-described briquette machine, and thus description thereof is omitted here.

FIG. 6-4 shows a schematic diagram of an example of a piston-type compression molding machine that can be used in the molding process 40. An example of a piston-type compression molding machine is a tablet machine. The molding machine shown in FIG. 6-4 includes a pair of pressure plates 401 and 402 arranged to face each other. At least one of the pressure plates 401 and 402 is provided so as to be able to reciprocate in the opposite direction (arrow A direction) by a driving means (not shown). A first mold 403 is fixed to one pressure plate 401, and a second mold 404 and a bottom plate 405 are fixed to the other pressure plate 402. The shape of the 1st type 403 and the 2nd type 404 may be arbitrary shapes according to the shape of coal molding fuel 200 finally obtained. For example, the second mold 404 can be a cylindrical member, and the first mold 403 can be a piston-like member that is slidably fitted into the hollow portion of the second mold 404. In this case, the bottom plate 405 can be a disk-shaped member disposed in the hollow portion of the second mold 404. The first mold 403, the second mold 404, and the bottom plate 405 form a molding mold, and the space surrounded by the first mold 403, the second mold 404, and the bottom plate 405 is a molding cavity 406.

In addition, the pressing plates 401 and 402 can incorporate heating means such as an electric heater as required. By this heating means, the mold temperature during molding is maintained at a predetermined temperature, and as a result, the temperature of the raw material (coal particles 4) during molding can be maintained at the predetermined temperature. The molding machine can further include thermocouples 407 and 408 as measuring means for measuring the mold temperature and measuring means for measuring the raw material temperature in the cavity 406, respectively. The thermocouple 408 for measuring the raw material temperature has a measuring part located in the cavity 406 during the measurement of the raw material temperature (see FIG. 6-4), and does not protrude into the cavity 406 when the raw material is pressurized. It is provided in the cavity 406 so as to be able to move forward and backward (in the direction of arrow B).

In the molding machine configured as described above, the first mold 403 is extracted from the second mold 404, and the raw material is charged into the hollow portion of the second mold 404 with the hollow portion open. After the raw materials are charged, the first mold 403 is inserted into the second mold 404, and the pressure plates 401 and 402 are brought close to each other so that the charged raw materials are compressed. At this time, the temperature of the mold is maintained at a predetermined temperature by heating means such as an electric heater built in the pressure plates 401 and 402. When a predetermined time has elapsed, the raw material in the cavity 406 is heat-molded. When the raw material is heat-molded, the first mold 403 and the second mold 404 are opened, and the heat-molded molded body is taken out from the cavity 406. Thereby, the tablet-shaped coal molding fuel 200 is obtained.

When such a piston type compression molding machine is used, the molding pressure (surface pressure) is preferably 0.5 to 2.5 ton / cm ² . Further, it is preferable that the pressurization time is 0.5 to 2.5 min and the pressurization holding time is 1 sec to 2 min. By molding the coal particles 4 under such conditions, the immersion moisture of the obtained coal-molded fuel 200 is reduced. Thereby, the water | moisture-content increase at the time of outdoor storage can be suppressed, and the calorie fall by the outdoor storage of the coal molding fuel 200 can be suppressed as a result. Here, the pressurization time means the time from the start of pressurization until reaching a predetermined molding pressure, and the pressurization holding time means the time for holding the molding pressure after reaching the molding pressure. To do.

Referring again to FIG. 6A, the molded body 5 obtained by the molding process 40 is supplied to the sieving process 70. In the sieving step 70, the coal powder remaining without being molded in the molding step 40 is removed from the molded body 5, and the molded body 5 from which the coal powder has been removed is obtained as the coal molded fuel 200. In the sieving step 70, a vibration sieving machine can be used. As the vibrating sieve, a circular sieve, a trommel sieve, or the like can be used. Among them, a sieve capable of continuous and mass processing is particularly preferable. In addition, what is necessary is just to implement the sieve process 70 as needed, and in the invention of Part F, it is not an essential process.

As described above, the coal molded fuel 200 obtained through the series of steps preferably has an apparent density of 1.0 to 1.4. The apparent density is a value measured based on “8. Measuring method of density and specific gravity by submerged weighing method” of JIS Z 8807.

Further, when molding is performed using a rotary molding machine in the molding step 40, it is preferable that the obtained coal molding fuel has a crushing strength per unit mass of 100 N / g or more. When the crushing strength is such a value, it can be said that durability during transportation is high. Here, the crushing strength per unit mass is the crushing strength measured by the test method specified in “3.1 Crushing strength test method” of JIS Z 8841-1993 “Granulated material—Strength testing method”. It is a value divided by the mass of the fuel 200.

On the other hand, when molding is performed using a piston-type compression molding machine in the molding step 40, it is preferable that the obtained coal molding fuel 200 does not collapse when immersed in water immediately after molding. When a piston-type compression molding machine is used in the molding step 40, the coal molding fuel 200 that does not collapse when immersed in water immediately after molding can be obtained by molding the coal particles 4 at a temperature of 50 to 150 ° C. The obtained coal-molded fuel 200 preferably has a total water content of 30 wt% or less when immersed in water for 72 hours or more after being held at room temperature for 24 hours after molding. By molding the coal particles 4 at a temperature of 95 to 150 ° C., it is possible to obtain a coal-molded fuel 200 having a water content of 30 wt% or less when immersed in water for 72 hours or more after being held at room temperature for 24 hours after molding.

[Embodiment F2]
6-5, a process for producing a coal-molded fuel according to embodiment F2 of the Part F invention is shown. This embodiment is different from the manufacturing process of Embodiment F1 in the following points (a) to (c).

(A) The molding process 40 in the embodiment F1 includes a first molding process 40A, a second crushing process 40B, and a second molding process 40C.

In the first molding step 40A and the second molding step 40C, as in the embodiment F1, a rotary molding machine (for example, a vertical supply type briquette machine and a horizontal supply type compactor) and a piston type compression molding machine (for example, a tablet machine) ) May be used.

A temperature adjustment function for adjusting the temperature of the coal 6 supplied to the second molding step 40C to 50 to 100 ° C., preferably 80 to 90 ° C., is any one between the crushing step 20 and the second molding step 40C. You may give to.

(B) The third crushing step 45A and polishing are performed after the molding step for the purpose of removing the poor-quality molded body contained in the molded body 7 obtained in the molding step (second molding step 40C in this embodiment). Step 45B is included. In this case, the fine powder generated in the third crushing step 45A and the polishing step 45B is also removed by the sieving step 70.

(C) As a measure against spontaneous ignition of coal-molded fuel, a cooling step 60A and / or a watering step 60B may be provided after the sieving step 70. In the cooling step 60A, it is desirable to use an air-cooling type cooling device, and the temperature of the cooled coal is desirably 40 ° C. or lower. When an air-cooling type cooling device is used, it is desirable to use air, an inert gas, or the like as the cooling medium. Moreover, by having the watering step 60B after the cooling step 60A, it is possible to suppress quality deterioration (such as strength reduction and collapse) of the coal-molded fuel.

[Temperature adjustment]
For adjusting the temperature of the coal supplied to the molding process, any method using heat exchange with a temperature-controlled fluid or the like can be used. Hereinafter, the temperature adjustment of the coal will be described by taking the coal 6 supplied to the second molding step 40C of the coal embodiment F2 as an example. The examples described below may be implemented alone, or two or more may be combined as appropriate when they can be combined.

When a roller mill or a ball mill is used in the pulverizing step 20, the temperature and flow rate of the mill operating gas are controlled, and the temperature is adjusted by bringing the mill operating gas into direct contact with the coal 3 'supplied to the pulverizing step 20. Can do. As the type of gas used, temperature-adjusted air, combustion exhaust gas, steam, cold gas, or the like can be used. Further, these gases may be mixed with a normal temperature gas to finely adjust the temperature. In addition, an inert gas (N ₂ , CO _2, etc.) can be used for the purpose of reducing the risk of powder ignition and dust explosion.

If the transport system of coal 6 between processes is an air transport system, the temperature and flow rate of the transport gas can be controlled, and the temperature can be adjusted by bringing the transport gas into direct contact with the coal 6. As the type of gas used, the same gas as the mill working gas can be used.

When heat exchange is performed in an indirect manner, temperature-adjusted coal contact equipment (for example, a device used in the previous process of the molding process, between processes) It is possible to adjust the temperature by placing a tube inside or on the outer periphery of a coal conveying device, intermediate storage device, etc., adjusting the temperature of the tube with a temperature adjusting medium, and bringing the coal into contact with the temperature adjusted tube. it can. As the temperature adjusting medium, gas (steam, combustion exhaust gas, cold gas, etc.), liquid (water, oil, etc.), etc. can be used.

Moreover, you may install a heater (or cooler) and a heat insulating material in the outer periphery of the said temperature control coal contact apparatus. In order to reduce the risk of powder ignition or dust explosion, inert gas (N ₂ , CO _2, etc.) may be purged inside the equipment and the intermediate storage device.

In temperature adjustment, a thermometer may be installed in the temperature-controlled coal contact device, and the temperature of the temperature adjustment medium may be controlled so that the temperature measured by the thermometer becomes a desired temperature (the temperature adjustment medium is a gas). In this case, the flow rate may be controlled). Moreover, you may adjust the temperature of coal by controlling the residence time of the conveying apparatus with a temperature adjustment function.

In addition, the temperature of the coal being processed rises due to frictional heat, compression heat, and natural heat generation of the coal due to contact with the temperature adjusting coal contact device. Due to the rise in the temperature of coal, the temperature of equipment, intermediate storage devices, etc. through which the coal being processed passes may vary. The degree of temperature fluctuation of these devices and apparatuses depends on environmental conditions (temperature, humidity), continuous operation time, physical properties of coal, and the like. Therefore, environmental conditions may be measured, and the temperature of the temperature-controlled coal contact device may be controlled based on the measurement result.

When there is a concern that the total moisture of the coal 6 is reduced due to the temperature adjustment and deviates from the preferable moisture range at the time of molding, the moisture of the coal 3 ′ discharged from the drying step 30 is increased in anticipation of the reduction of the total moisture. You may implement the drying process 30 so that it may become. Conversely, when there is a possibility that the moisture of the coal 6 will rise due to the influence of moisture in the working gas used in the pulverization step 20 during temperature adjustment, the coal 3 ′ discharged from the drying step 30 The drying process may be carried out so that the moisture becomes lower, or the humidity of the working gas used in the pulverization process 20 may be adjusted to be lower.

Furthermore, when the above-described temperature adjustment causes deformation (expansion, contraction) of devices used in each process, inter-device transfer equipment, intermediate storage devices, and the like, and a stable operation may be hindered, a temperature adjustment function is provided. Depending on the temperatures of the coals 3 ′, 4, 5 ′, and 6 in each process, materials to be configured may be selected so that the apparatus used in each process is not deformed.

The explanation of the sign of the main elements related to the description of Part F is as follows.

DESCRIPTION OF SYMBOLS 10 Crushing process 10A 1st crushing process 20 Crushing process 30 Drying process 40 Molding process 40A 1st molding process 40B 2nd crushing process 40C 2nd molding process 41 Roll 42, 45 Supply means 45A 3rd crushing process 45B Polishing process 46 Supply port 70 Sieve Process 60A Cooling Process 60B Watering Process 401, 402 Pressure Plate 403 First Type 404 Second Type 405 Bottom Plate 406 Cavity 407, 408 Thermocouple

<< Example of Part A >>
Example 1 corresponds to the manufacturing method of Embodiment 1 shown in FIG. 1-1, and the molded body 100 obtained through the crushing step 10, the drying step 20, the crushing step 30, the molding step 40, and the sieving step 50 is coal-molded. It is intended as fuel. In Example 1, quality evaluation of the obtained coal-molded fuel was performed according to Example 1-1 and Example 1-2 described below. Tables A2 and A3 show the properties of the coal used in Examples 1-1 and 1-2.

Fig. 1-6 shows a photograph of the manufactured coal-molded fuel.

(Example 1-1: Corresponding to Embodiment 1)
Example 1-1 corresponds to Embodiment 1 shown in FIG. 1-1, and B coal, Indonesian lignite, was used as the raw material coal. First, the B charcoal was pulverized in the crushing step 10 using a Hanmark lasher so that the average particle size was 10 mm or less. Next, the pulverized B charcoal was dried in the drying step 20 using a steam tube dryer so that the total moisture of the dried coal 3 was 11.8%. In the subsequent pulverization step 30, the dried B charcoal was pulverized using a roll mill so that the average particle size was 20 μm. Next, the coal particles 4 obtained by the pulverization step 30 were molded in the molding step 40.

The coal particles 4 were molded using a briquette machine, which is a vertical feeding type molding machine shown in FIG. 1-2. The used briquette machine had a pair of rolls 41, of which only one roll 41 had a roll pocket, and the other roll 41 had a flat outer peripheral surface without irregularities. The pair of rolls 41 had a diameter of 520 mm and an axial length of 236 mm.

There were two types of roll pocket shapes, shape A shown in FIGS. 1-8A and 8B and shape B shown in FIGS. 1-9A and 9B. The size of the shape A is 6 mm in the vertical length a, 9 mm in the horizontal length b, 1.57 mm in the depth c, and the size of the shape B is 2.5 mm in the vertical length a, 8 mm in the horizontal length b, and the depth c. It was 0.6 mm. On the peripheral surface of one roll 41, 5244 roll pockets having shape A and 184 roll pockets having shape B were regularly distributed. The volume per shape A was 0.035 cm ³ and the volume per shape B was 0.0048 cm ³ . Further, if the gap between the rolls 41 is large, leakage of the coal particles 4 and pressure dispersion are likely to occur, so the gap d between the rolls 41 is set to 1 mm, which is the design lower limit. The rotation speed of the roll 41 and the screw feeder was adjusted so that the roll linear pressure was maintained at 7 t / cm.

The plate-shaped intermediate molded body 5 was obtained by the molding process 40. The obtained intermediate molded body 5 includes coal particles 4 leaking from between the rolls 41 and coal powder generated by crushing during the molding.

After the molding step 40, the molded body 5 containing the coal particles 4 was supplied to the sieving step 50, and the coal powder (including the coal particles 4) contained in the intermediate molded body 5 was removed. In the sieving step, a sieve having an aperture of 3.35 mm was used. The molded body 100 from which the coal powder was removed by the sieving step 50 was used as a coal molded fuel.

The yield of the molded body 100 obtained by removing the coal powder obtained in the sieving step 50 was 63.2%. Further, the obtained molded body 100 had a maximum width of 236 mm, and had at least a part of one or a plurality of protrusions corresponding to the shape of the pocket formed on the roll 41 on one side. Moreover, when the thickness of the molded object 100 in parts other than a protrusion corresponding to the clearance gap d between the rolls 41 was measured, it was 3.3 mm. From this, it was found that the roll 41 was retracted by the pressure of the coal particles 4 supplied between the rolls 41 during the molding step 40 and the interval between the rolls 41 was widened.

(Example 1-2: corresponding to Embodiment 1)
A coal-molded fuel was obtained in the same procedure as in Example 1-1, except that K coal, Indonesian lignite, was used as a raw material. However, the total moisture of the dried coal 3 obtained in the drying step 20 is 13.1%, and the average particle diameter of the coal particles 4 obtained in the pulverization step 30 is 24 μm. The yield of the molded body 100 from which the powder was removed was 62.4%. The thickness of the molded body 100 other than the protrusions was 4.0 mm.

(Comparative Example 1)
Comparative Example 1 corresponds to Embodiment 1 shown in FIG. 1-1, and B coal which is Indonesian lignite was used as the raw material coal. First, this B charcoal was crushed in the crushing step 10 using a Hanmark lasher so that the average particle diameter was 10 mm or less. Next, the crushed B coal 2 was dried in a drying step 20 using a steam tube dryer so that the total moisture of the dried coal 3 was 13 to 15%. In the subsequent pulverization step 30, the dried coal 3 was pulverized using a ball mill so that the average particle size was 18 μm. Next, the coal particles 4 were molded in the molding process 40.

In the molding process 40, the vertical supply briquette machine shown in FIG. 1-2 was used. The briquette machine used had a pair of rolls 41, and roll pockets were formed on both rolls 41. The pair of rolls 41 had a diameter of 520 mm and an axial length of 120 mm.

The shape of the roll pocket was as shown in FIGS. 1-3A and 3B. The gap d between the rolls 41 was 1 mm. The rotation speed of the roll 41 and the screw feeder was adjusted so that the roll linear pressure was maintained at 7 t / cm.

The intermediate molded body 5 was obtained by the molding process 40. The obtained intermediate molded body 5 includes coal particles 4 leaking from between the rolls 41 and coal powder generated by crushing during the molding.

After the molding process 40, the molded body 5 was supplied to the sieving process 50, and the coal powder contained in the intermediate molded body 5 was removed. In the sieving step, a sieve having an aperture of 9.5 mm was used. The molded body 100 from which the coal powder was removed by the sieving step 50 was used as a coal molded fuel.

The yield of the molded product 100 obtained by removing the coal powder obtained in the sieving step 50 was 83.2%. Further, the obtained molded body 100 had a briquette shape corresponding to the concave portion of the pocket formed on the roll 41. Moreover, when the thickness of the molded object 100 in parts other than a protrusion corresponding to the clearance gap d between the rolls 41 was measured, it was 4.8 mm. From this, it was found that the roll 41 was retracted by the pressure of the coal particles 4 supplied between the rolls 41 during the molding step 40 and the interval between the rolls 41 was widened.

(Evaluation)
The molded body 100 obtained in Example 1-1, Example 1-2, and Comparative Example 1 was evaluated according to the following evaluation items.

[Crushing strength]
It was measured based on “3.1 Crushing strength test method” of JIS Z 8841-1993.

[Apparent density]
Measured based on “8. Measuring method of density and specific gravity by submerged weighing method” of JIS Z 8807.

[Powdering characteristics]
The pulverization characteristics were performed by the following procedure (pulverization treatment → evaluation of pulverization characteristics) simulating the impact force the molded body receives during bulk transportation.

(Powdering process)
After packing 1 kg of the molded body in a strong sandbag, the sandbag containing the molded body was dropped 20 times from a height of 8.6 m. Thereafter, the contents of the sandbag were taken out and subjected to 800 rotations using a testing machine described in “3.2 Rotational Strength Test Method” of JIS Z 8841-1993 (Strength Test Method for Granulated Products).
(Powdering property evaluation)
Weigh the mass of the molded product after pulverization. Next, the molded product after pulverization is sieved with a sieve having an opening of 2 mm, and the mass under the sieve is measured. The value obtained by calculating the ratio (hereinafter sometimes referred to as -2 mm) of passing through a sieve having a mesh opening of 2 mm in the molded product after pulverization treatment by the following formula (2) Used for

Generally, when bulk handling of coal, coal with a 2 mm sieve passing rate exceeding 30% has a risk of handling trouble (adhesion, blockage). Therefore, regarding the pulverization characteristics required for the coal-molded fuel in this example, it was determined that there was no problem if the value obtained by equation (2) was 30% or less according to this criterion.

[Immersion moisture]
The molded body was immersed in water, and when 7 days had passed since the start of immersion, the molded body was collected, and water adhering to the surface was removed with a cloth such as a waste cloth. Then, the value measured based on the total moisture measurement method of coals described in JIS M 8820-0 (Coal and coke-lot total moisture measurement method) was defined as immersion moisture.

[Natural fever index]
Spontaneous heat generation risk in the form (moisture, particle size) at the time of bulk transport of the molded body was evaluated by the following procedure.

After packing 1 kg of the molded body in a strong sandbag, the sandbag containing the molded body was dropped 20 times from a height of 8.6 m. Thereafter, the contents of the sandbag bag were taken out and subjected to 800 rotations using a testing machine described in “3.2 Rotational Strength Test Method” of JIS Z 8841-1993 (Strength Test Method for Granulated Products). The entire amount of processed material (that is, 1 kg) was collected, packed in a plastic bag, and then added with water so that the total water content of the processed material was 23%. After hydration, it was hermetically sealed in a plastic bag for 2 days at room temperature.

Thereafter, 1 kg of the cured sample was put into the test apparatus shown in FIG. 1-10. The test apparatus includes a thermostat and a reactor disposed in the thermostat, and a sample is put into the reactor. A gas supply pipe connected with a nitrogen cylinder and an air cylinder is connected to the reactor. The gas supplied through the gas supply pipe can be switched by a three-way cock. The gas supply pipe is provided with a flow meter, and the flow rate of the gas flowing through the gas supply pipe can be measured. A thermometer is installed in the reactor. Furthermore, a gas sampling pipe in which a gas concentration meter is installed is connected to the reactor.

After putting the sample into the reactor, first, nitrogen gas was introduced into the reactor, and the thermostat was heated to 80 ° C. in a nitrogen gas atmosphere. After raising the temperature of the thermostat, the gas introduced into the reactor was switched to air, and the gas in the reactor was replaced with air. The gas in the reactor was replaced with air, and the gas concentration (O ₂ concentration, CO ₂ concentration, CO concentration) was measured with a gas concentration meter when 300 minutes had elapsed. After measuring the gas concentration, a natural exothermic index corresponding to the amount of heat generated by the oxygen adsorption / oxidation reaction was calculated.

SCI = O ₂ adsorption heat + CO ₂ production heat + CO production heat (Formula 3)
Here, SCI is a spontaneous combustion index. The evaluation standard of SCI is that it does not exceed the SCI measurement value (SCI = 12) of subbituminous coal, which has a high risk of spontaneous heat generation, among ordinary coal that is usually handled.

The evaluation results of Example 1-1, Example 1-2, and Comparative Example 1 are shown in Table A4.

(Example 2: corresponding to Embodiment 2)
Example 2 corresponds to Embodiment 2 shown in FIGS. 1-7, and B coal, which is Indonesian lignite, was used as the raw material coal. First, B charcoal was crushed in the first crushing step 10 using a Hanmark lasher so that the average particle size was 10 mm or less. Next, in the drying step 20, the first crushed charcoal 2 was dried to 13% using a steam tube dryer. The dry charcoal 3 was pulverized in the pulverizing step 30 to an average particle size of 20 μm using a roller mill. Next, the coal particles 4 obtained in the pulverization step 30 were molded in the first molding step 40. In the first molding step 40, a compactor which is a horizontal supply type molding machine was used. The roll had a diameter of 160 mm and a width direction length of 60 mm. The shape of the roll pocket was as shown in FIGS. 1-4. The gap between the rolls was 1 mm, and the roll linear pressure was 1 t / cm. The apparent density of the first intermediate molded body 5 was 1.0 g / cm ³ . The obtained plate-shaped first intermediate molded body 5 was processed in the second crushing step 10a using a Hanmark lasher so that the average particle diameter was 0.11 mm. Next, in the second molding step 40a, the plate-like second intermediate molded body 7 was molded using a briquette machine.

In the second molding step 40a, a briquette machine, which is a vertical feeding type molding machine shown in FIG. 1-2, was used. The used briquette machine has a pair of rolls 41, of which only one of the rolls 41 has a pocket, and the other roll 41 has a flat outer peripheral surface with no irregularities. The pair of rolls 41 had a diameter of 250 mm and an axial length of 50 mm.

There were two types of roll pocket shapes, shape A shown in FIGS. 1-8A and 8B and shape B shown in FIGS. 1-9A and 9B. The size of the shape A is 6 mm in the vertical length a, 9 mm in the horizontal length b, 1.57 mm in the depth c, and the size of the shape B is 2.5 mm in the vertical length a, 8 mm in the horizontal length b, and the depth c. It was 0.6 mm. On the peripheral surface of one roll 41, 484 roll pockets having shape A and 88 roll pockets having shape B were regularly distributed. The volume per shape A was 0.035 cm ³ and the volume per shape B was 0.0048 cm ³ . Also, if the gap between the rolls 41 is large, powder leakage of the raw material and pressure dispersion are likely to occur. The rotation speed of the roll 41 and the screw feeder was adjusted so that the roll linear pressure was maintained at 5 t / cm.

A plate-like second intermediate molded body 7 was obtained by the second molding step 40a. The obtained second intermediate molded body 7 includes a crushed material 6 leaked from between the rolls 41 and coal powder generated by crushing during the molding.

After the second molding step 40a, the second intermediate molded body 7 containing the second crushed coal 6 is supplied to the sieving step 50, and the coal powder (the second crushed coal 6 is contained in the second intermediate molded body 7). Including) was removed. In the sieving step, a sieve having an aperture of 3.35 mm was used. The plate-like molded body 200 from which the coal powder was removed by the sieving step 50 was used as a coal-molded fuel.

The yield of the coal-molded fuel 200 obtained in the sieving step 50 was 81.8%. The obtained coal-molded fuel 200 had a width of 50 mm at the maximum, and had at least a part of one or a plurality of protrusions corresponding to the shape of the pocket formed on the roll 41 on one side. In addition, the thickness of the molded body 100 at a portion other than the protrusion, which corresponds to the gap d between the rolls 41 (the set value of d is 1 mm), was 4.6 mm. From this, it was found that the roll 41 was retracted by the pressure of the coal particles 4 supplied between the rolls 41 during the molding step 40 and the interval between the rolls 41 was widened.

(Evaluation)
The coal molding fuel 200 obtained in Example 2 was evaluated using the same evaluation items as in Example 1. The evaluation results of Example 2 are shown in Table A5.

The molded body is assumed to be bulk transport (shipping, truck transport). Therefore, it can be said that the higher the crushing strength and the higher the apparent density, the higher the durability during transportation and the better the quality. In addition, it can be said that the lower the powdered powder, −2 mm, the spontaneous heating index and the immersion moisture, the better the quality.

<< Example of Part B >>
Hereinafter, the invention of Part B will be specifically described using examples, but the invention of Part B is not limited thereto.

<Example B1-7>
Examples B1 to 7 correspond to the manufacturing method of the embodiment B2 shown in FIG. 2-2, and the first crushing step 10, the drying step 20, the crushing step 30, the first molding step 40, the second crushing step 10a, the second crushing step This relates to the product 200 obtained through the molding process 40a and the curing process 85.

(Manufacture of modified coal)
The raw materials used were Indonesian B charcoal and T charcoal (both lignite). Properties of T charcoal and B charcoal are shown in Table B1. In Table B1, AR represents an arrival base, AD represents an air-drying base, and DB represents an anhydrous base (JIS M8810). Table B1 shows the fuel ratio, high calorific value and elemental analysis results calculated based on industrial analysis values (air-dry basis). The industrial analysis values and elemental analysis values in Table B1 are based on JIS M8812, 8813, and 8814. In Table B1, GAR, GAD, and DAF respectively indicate arrival base high calorific value, air-dry base high calorific value, and anhydrous ashless base high calorific value (JIS M8810). HGI (hard glove index) was measured based on “7. Crushability test method (hard glove method)” of JIS M8801.

In the first crushing step 10, the raw T charcoal or B charcoal was crushed to an average particle size of 10 mm or less using a Hanmark lasher. Next, in the drying step 20, the crushed T charcoal was dried using a steam tube dryer so that the total water content was 5 to 20% by weight. Next, in the pulverizing step 30, a coal mill 4 was obtained by pulverizing so as to have an average particle diameter of about 10 to 60 μm using a ball mill. The average particle size of the coal crushed in the first crushing step 10 is measured based on JIS M8801-2004 “5. Particle size test method”, the passing sieve mass percentage of each sieve opening is obtained, and the passing sieve mass percentage is 50 % Particle diameter was defined as the average particle diameter. The average particle diameter of the coal particles 4 pulverized in the pulverization step 30 is a median diameter of a particle size distribution obtained by a laser diffraction / scattering method.

The coal particles 4 were supplied to the vertical supply briquette machine shown in FIG. 2-3, and the first molding step 40 was performed to obtain the first molded body 5. The vertical supply type molding machine (briquette machine) used in the first molding step 40 has a pair of rolls 41, and roll pockets were carved on both the two rolls 41. Each of the pair of rolls 41 had a diameter of 250 mm and an axial length of 50 mm.

There were two types of pocket shapes of the vertical supply type molding machine used in the first molding step 40: shape A shown in FIG. 2-4 and shape B shown in FIG. 2-5. Shape A has a longitudinal length a of 6 mm, a lateral length b of 9 mm, and a depth c of 1.57 mm. Pocket B has a longitudinal length a of 2.5 mm, a lateral length b of 8 mm, and a depth c of 0.6 mm. Met. On the peripheral surface of the roll 41, 484 pockets having the shape A and 88 pockets having the shape B were regularly distributed and arranged per roll. The volume per shape A was 0.035 cm ³ and the volume per shape B was 0.0048 cm ³ . The gap d between the two rolls was 1.0 mm, and the rotation speeds of the roll 41 and the screw feeder were adjusted so that the roll linear pressure was maintained at 5 t / cm.

The first molded body 5 obtained in the first molding step 40 was crushed to an average particle size of 0.05 to 1.0 mm with a Hanmark lasher in the second crushing step 10a. The obtained crushed material 6 was molded by a vertical supply type molding machine (briquette machine) in the second molding step 40a to obtain a plate-like second molded body 7. The pocket shape of the molding machine used in the second molding step 40a is the same as the pocket shape used in the first molding step 40. The gap between the two rolls was 1.0 mm, and the roll linear pressure was adjusted to 5 t / cm.

The obtained second molded body 7 was treated with a sieve (aperture 3.35 mm), sealed in a vinyl bag in a curing step 85, and cured (temperature: −5 to 35 ° C., ambient relative humidity: 30 to 90%). The product 200 was obtained after the curing days described in Table B3.

The quality in each process of T charcoal or B charcoal before the curing process is as shown in Table B2. In Table B2, there is no description of the quality of the second crushed material 6 and the second molded body 7 of Example B4, but it is simply because the quality is not measured, and actually the second crushing step 10a as in the other examples. And the 2nd molded object 7 is obtained through the 2nd shaping | molding process 40a.

<Quality evaluation>
The quality evaluation method of the obtained product 200 is as follows.

<Moisture>
The total moisture before dipping the product 200 in water and the moisture dipped in the product 200 in water were described.

<Thickness>
The thickness in the present application is the distance between the smooth surfaces of the plate-shaped molded body (not including the convex surface, the portion corresponding to d in FIGS. 2-4 and 2-5), and the thickness of 10 samples collected at random. Is the average value. The thickness was measured by applying calipers to the flat surfaces of the plate-shaped molded body.

<Expansion rate during immersion>
Assuming that the cube of the thickness of the product 200 is the volume of the product 200, the following (formula 1 ′):

により、水中浸漬７日目の膨張率を算出した。

Thus, the expansion coefficient on the seventh day of immersion in water was calculated.

The quality evaluation results (immersion moisture, thickness, etc.) of the product 200 are shown in Table B3. In addition, let the curing days in Table B3 be the days from the day when the 2nd molded object 7 was obtained.

Fig. 2-6 shows the relationship between the number of days of curing and the immersion moisture (wt%) on the 7th day for the product 200. It was confirmed that the immersion moisture of the product 200 decreases as the storage period (curing days) increases, and that the level is flat after the curing days 200 days.

Fig. 2-7 shows the relationship between the number of days of curing and the thickness (mm) before immersion in water for the product 200. It was confirmed that the thickness of the opposing smooth surfaces increases with the curing days.

Fig. 2-8 shows the relationship between the number of days of curing and the expansion rate on the seventh day of immersion of the molded product in water for the product 200. As shown in Fig. 2-8, the expansion coefficient of the molded product before curing is 1.6, whereas the expansion coefficient before and after immersion of the product 200 cured for 200 days or more is 1.110 to 1.231. Water absorption during immersion is suppressed.

<< Example of Part C >>
Hereinafter, one aspect of the invention of Part C will be described in more detail based on examples. However, the invention of Part C is not limited to the contents of the following examples.

<Example C1-1>
(Manufacture of modified coal)
In this example, Indonesian B charcoal was used as the raw material (see Table C1). In Table C1, “AR” indicates arrival base, “AD” indicates air-drying base, and “DB” indicates anhydrous base (JIS M8810). Table C1 also shows the fuel ratio calculated based on the industrial analysis values (air-dry basis), the higher heating value, and the results of elemental analysis.

Industrial analysis values and elemental analysis values are based on JIS M8812, 8813, 8814. In Table C1, GAR, GAD, and DAF indicate arrival base high calorific value, air dry base high calorific value, and anhydrous ashless base high calorific value (JIS M8810), respectively. HGI (hard glove index) was measured based on “7. Crushability test method (hard glove method)” of JIS M 8801.

First, in the first crushing step 10, the raw material was crushed to an average particle size of 10 mm or less using a Hanmark lasher. Next, in the drying step 20, drying was performed using a blow dryer so that the total water content was 5 to 20 wt%. Next, in the pulverizing step 30, coal was pulverized by using a ball mill so that the average particle diameter was about 10 to 60 μm, whereby coal particles 4 were obtained.

Next, the coal particles 4 obtained in the pulverization step 30 were supplied to the briquette machine of FIG. 3-2, and the first molding step 40 was performed to obtain the first molded body 5. Next, in the second crushing step 10a, the first molded body 5 was pulverized so as to have an average particle diameter of 0.05 to 0.5 mm using a Hanmark lasher.

Next, in the second molding step 40 a, the crushed material obtained in the above step was molded with the same type of briquette machine as in the first molding step 40. The gap between the rolls was 1.0 mm, and the roll linear pressure was 5 t / cm. Thereby, a plate-like second molded body 7 was obtained. Next, in the sieving step 70, the second molded body 7 was manually sieved using a sieve (aperture 3.35 mm) to obtain a product 8 remaining on the sieve.

Next, in the heat curing step 85, the sieve obtained in the above step was processed. The heat curing conditions were as follows.

(Heat curing)
28 g of the sample was put into a weighing bottle, and the weighing bottle was covered with aluminum foil for the purpose of suppressing evaporation of all the water, and then heat curing was performed with a blower dryer. The blower dryer was set at 107 ° C., and the heat curing time was 20 minutes. The product after heating and curing was left indoors and returned to room temperature, and the product of “Example C1-1” was designated.

<Example C1-2>
Example C1-2 is the same as Example C1-1 except for the treatment method of the heat curing step 85. In Example C1-2, 28 g of a sample was put into a weighing bottle, and heat curing was performed with a blow dryer without a lid. The temperature of the blast dryer and the heat curing time are the same as in Example C1-1 (107 ° C., 20 minutes). The product after heating and curing was left indoors and returned to room temperature, and the product of “Example C1-2” was designated.

<Comparative Example C1>
In Comparative Example C1, the product obtained in the sieving process 70 of Example C1-1 was directly used as a product without performing the heat curing process.

<Result>
The total water content and the water content of the products obtained in Example C1-1, Example C1-2, and Comparative Example C1 were measured. The results are shown in Table C2.

In Example C1-1, since aluminum foil was applied to the weighing bottle during heat curing, the total moisture after heat curing was almost the same as Comparative Example C1 (without heat curing).

The water immersed in Example C1-1 was about 4% lower than the water immersed in Comparative Example C1, and it was confirmed that the water immersed in water was improved by heat curing.

In Example C1-2, the weighing bottle is not capped at the time of heat curing, so the total moisture is evaporated by the heat curing, and the total moisture after the heat curing is about half that of Example C1-1 and Comparative Example C1. It had dropped to. The water immersed in Example C1-2 is improved compared to Comparative Example C1, but it is about 2% higher than the water immersed in Example C1-1. Therefore, the quality of the final product is as follows. It can be said that the moisture immersed in water is improved by suppressing the evaporation of the total water.

<Analysis method>
(About total moisture)
“Total moisture” was measured by the total moisture measurement method for coals described in JIS M 8820-2000 (Coal and cokes—total lot moisture measurement method).

(Water immersed in water)
“Water immersed in water” can be measured by the following method. The sample was immersed in water, and after 7 days from the start of immersion, the reformed coal was collected, and the moisture adhering to the surface was removed with a cloth such as waste cloth, and then JIS M 8820-2000 (coal and coke- The total moisture obtained by the method for measuring the total water content of the coals described in the method for measuring the total water content of the lot) was defined as the water immersed in water.

Since the amount of water absorption due to rainfall during storage decreases, the calorific value, which is the product value, increases. Therefore, the lower the moisture immersed in water, the higher the value as a fuel.

(Crushing strength)
It was measured based on “3.1 Crushing strength test method” of JIS Z 8841-1993.
(Apparent density)
Measured based on “8. Measuring method of density and specific gravity by submerged weighing method” of JIS Z 8807.
(Thickness)
The thickness in the present application is the distance between the convex surfaces of the plate-shaped molded body, and the average value of the thicknesses of 10 samples collected at random is the result. The thickness was measured by applying a caliper to the convex surfaces of the sample.

<Example C2>
Example C2 corresponds to the manufacturing method of FIG. 3-1, and includes a first crushing step 10, a drying step 20, a crushing step 30, a first molding step 40, a second crushing step 10a, a second molding step 40a, and a sieving step. 70 and the heat curing process 85 are processed in this order, and the resulting molded body 200 is used as a coal molded fuel. The same as Example C1-1 except for the method of the heat curing process.

In the heat curing process 85, the coal 8 (molded body) obtained in the sieving process 70 is placed in a vinyl bag and cured at room temperature for 25 days, and then placed in a vat, and an aluminum foil is formed in the same manner as in Example C1-1. Then, heat curing was performed with a blow dryer. The temperature of the blower dryer was 107 ° C., and the curing time was 50 minutes.

<Comparative Example C2>
In Comparative Example C2, the heat curing step of Embodiment 2 was not performed, and the coal 8 (molded body) on the sieve obtained in the sieving step 70 was placed in a vinyl bag and cured at room temperature for 25 days.

(Result 2)
In order to investigate changes in physical properties associated with heat curing, the apparent density, thickness, and crushing strength were measured in addition to total moisture and moisture immersed in water (Table C3). Although the total moisture before and after the heat curing was almost the same, the results were greatly different in the water immersed in water. As other physical property changes, it was found that the thickness of the molded body increased (expanded) by heat curing. In addition, the immersion expansion coefficient E in water was calculated | required by the following:

Underwater immersion expansion rate E = thickness Tw after immersion in water ÷ thickness T

<< Example of Part D >>
Hereinafter, the invention of Part D will be specifically described using examples, but the invention of Part D is not limited thereto.

In the following examples, the raw material and product evaluation methods are as follows.

<Evaluation method>
<HGI (Hard Grove Index)>
It was measured based on “7. Crushability test method (hard glove method)” of JIS M8801.

<Bulk density>
The bulk density was calculated by the formula (1) from the weight of the filled sample and the volume of the container after the sample was ground and filled into a container of about 2-5 L having a known volume. In addition, the method of throwing into the container differs between rough filling and dense filling. In the rough filling, the sample was filled so as not to be compacted as much as possible when it was put into the container, and the dense filling was performed while tapping the container. The number of tapping was 10 times.
Bulk density = packed sample mass ÷ container volume equation (1)

<Crushing strength>
It was measured based on “3.1 Crushing strength test method” of JIS Z 8841-1993.

<Apparent density>
Measured based on “8. Measuring method of density and specific gravity by submerged weighing method” of JIS Z 8807.

<Powdering characteristics>
The pulverization characteristics were carried out by the following procedure simulating the impact force that the sample receives during bulk transportation. After packing 1 kg of a sample in a strong sandbag, the sandbag containing the sample is dropped 20 times from a position of 8.6 m in height, and “3.2 of JIS Z8841-1993 (Granulated Product Strength Test Method)”. The rotational strength tester described in “Rotational strength test method” was subjected to 800 rotational processing. A value obtained by sieving the treated sample with a sieve having a mesh opening of 2 mm, and obtaining a ratio of -2 mm (mass ratio of the sample having passed through a sieve with a mesh opening of 2 mm) after pulverization by the following formula (2) Was used for evaluation of powdering characteristics. In the formula (2), “−2 mm mass of the sample after treatment” refers to the mass of the sample after treatment which has passed through a sieve having an opening of 2 mm.

Ordinarily, when bulk handling coal, coal with a 2 mm sieve passage integration rate exceeding 30% may cause handling trouble (adhesion, blockage). Therefore, regarding the powdering characteristics required for the molded body (or granulated body) in this example, it was determined that there was no problem if the value obtained by the above formula (2) was 30% or less according to this criterion.

<Natural fever index>
The spontaneous heat risk in the form (moisture, particle size) at the time of bulk transport of the molded body was evaluated by the following procedure. After packing 1 kg of the molded body in a strong sandbag, the sandbag containing the molded body is dropped 20 times from a position of 8.6 m in height, and the JIS Z8841-1993 (Granulated product strength test method) “3. The rotational strength tester described in “2 Rotational Strength Test Method” was subjected to 800 rotational treatments, and 1 kg of the processed product was recovered and packed in a plastic bag, and then watered so that the total moisture of the processed product was 23% by weight. After the hydration, it was hermetically sealed (hydrated) at room temperature (about 25 ° C.) for 2 days in a plastic bag.

Thereafter, 1 kg of the hydrolyzed sample was put into the constant temperature layer of the test apparatus having the configuration shown in FIG. 4-5. The test apparatus includes a thermostat and a reactor disposed in the thermostat, and a sample is put into the reactor. A gas supply pipe connected with a nitrogen cylinder and an air cylinder is connected to the reactor. The gas supplied through the gas supply pipe can be switched by a three-way cock. The gas supply pipe is provided with a flow meter, and the flow rate of the gas flowing through the gas supply pipe can be measured. A thermometer is installed in the reactor. Furthermore, a gas sampling pipe in which a gas concentration meter is installed is connected to the reactor.

After putting the sample into the reactor, the thermostatic chamber was heated to 80 ° C. in a nitrogen atmosphere. After the temperature was raised to 80 ° C., the gas was switched to air, and the gas concentration (O ₂ concentration, CO ₂ concentration, CO concentration) after the reaction was measured for a predetermined time (300 minutes). A spontaneous exothermic index SCI (Spontaneous Combustion Index) corresponding to the amount of heat generated by the oxidation reaction was calculated.

SCI = O ₂ adsorption heat + CO ₂ production heat + CO production heat Formula (3)

The SCI tolerance (judgment criteria) was judged to be acceptable if it does not exceed the SCI measurement value (12) of subbituminous coal, which has a particularly high risk of spontaneous heating, among ordinary coals that are usually handled.

<Immersion moisture>
The molded body is immersed in water, and when 7 days have passed since the start of immersion, the molded body is recovered, and moisture attached to the surface is removed with a cloth such as a waste cloth, and then JIS M 8820-2000 (coal and coke- The total moisture obtained by the method for measuring the total water content of the coals described in the “Total Moisture Measurement Method for Lots” was used as immersion water.

Since the molded body is assumed for bulk transportation (shipping, truck transportation), the higher the crushing strength and the higher the apparent density, the higher the durability during transportation and the better the quality. Moreover, the lower the ratio of −2 mm after pulverization, the lower the spontaneous heating index, and the lower the immersion moisture, the better the quality.

<Reference Example D1>
The method for producing a coal-molded fuel in Reference Example D1 corresponds to FIG. 4-1, and includes a first crushing step 10, a drying step 20, a pulverizing step 30, a first molding step 40, a second crushing step 10a, and a second molding step. The molded body 100 obtained through 40a and the sieving step 70 is used as a coal-molded fuel. However, a vertical feeding briquette machine was used as the molding machine in the first molding step.

The raw material was B coal, Indonesian lignite. The properties of B charcoal are shown in Table D1. In Table D1, AR represents an arrival base, AD represents an air-drying base, and DB represents an anhydrous base (JIS M8810). Table D1 shows the fuel ratio, high calorific value and elemental analysis results calculated based on industrial analysis values (air-dry basis). The industrial analysis values and elemental analysis values in Table D1 are based on JIS M8812, 8813, and 8814. In Table D1, GAR, GAD, and DAF respectively indicate arrival base high calorific value, air-dry base high calorific value, and anhydrous ashless base high calorific value (JIS M8810).

In the crushing step 10, it was crushed to an average particle size of 10 mm or less using a Hanmark lasher. Next, in the drying step 20, drying was performed using a steam tube dryer so that the total moisture was 12.7% by weight. In the subsequent pulverizing step 30, a roller mill was used to obtain coal particles 4 having an average particle diameter of 24 μm. The average particle size of the coal crushed in the first crushing step 10 is measured based on JIS M 8801-2004 “5. Particle size test method”, the passing sieve mass percentage of each sieve opening is obtained, and the passing sieve mass percentage is obtained. Was the average particle size. The average particle size of the coal particles 4 pulverized in the pulverization step 30 was the median size of the particle size distribution obtained by the laser diffraction / scattering method.

In the first molding step 40, a vertical molded briquette machine shown in FIG. 4-4 was used to obtain a first molded body having an apparent density of 1.0 g / cm ³ . The briquette machine used in the first molding process has a pair of rolls 61, of which only one roll 61 has a roll pocket, and the other roll 61 has a flat outer peripheral surface without unevenness. Was.

The plate-shaped first molded body 5 was obtained by the first molding step 40. Moreover, when the 1st molded object 5 obtained by the 1st shaping | molding process was processed with the sieve mesh 3.35mm, the weight ratio of the 1st molded object 5 on a sieve with respect to the total weight of the coal particle 4 supplied to the briquette machine Was 52.5%.

Subsequently, in the second crushing step 10a, the first molded body 5 is crushed using a hammer mark lasher at a hammer rotation speed of 750 rpm, and the second crushed material having an average particle diameter of 0.12 mm and a bulk density of 0.58 g / cm ³ . 6 was obtained. The particle size distribution of the second crushed material 6 in Reference Example D1 is shown in FIG. 4-6.

The obtained second crushed material 6 was molded by a briquette machine in the second molding step 40a. A briquette machine similar to the briquette machine used in the first molding step 40 was used. As in the first molding step 40, the gap between the two rolls 61 was 1 mm, and the rotation speed of the rolls and screws was adjusted so that the roll linear pressure was 7 t / cm. The obtained plate-shaped second molded body 7 was processed in the sieving step 70, and the molded body 100 was formed on the sieve. In the sieving step 70, a sieve having an opening of 3.35 mm was used. The yield of the molded body 100 obtained in the sieving step 70 was 89.9%. The quality evaluation results of the molded body 100 are shown in Table D2. The quality of the molded body 100 was good.

<Example D1>
Example D1 corresponds to the production method shown in FIG. 4-2. First, coal particles obtained in the crushing step 10, the drying step 20, and the crushing step 30 were divided into 4-1 and 4-2. Subsequently, the coal particles 4-1 are made into the first molded body 5 by the first molding step 40, the first molded body 5 and the coal particles 4-2 are mixed, and the second crushing step 10a is performed. 6 was obtained. That is, a part of the coal particles (4-2) obtained in the pulverization step 30 was directly used as a raw material for the second crushing step 10a without going through the first molding step 40.

The raw material was B coal, Indonesian lignite, as in Reference Example D1. In the crushing step 10, it was crushed to a mean particle size of 10 mm or less using a Hanmark lasher. In the drying step 20, drying was performed using a steam tube dryer so that the total water content was 12.7% by weight. In the subsequent pulverizing step 30, a roller mill was used to pulverize to an average particle size of 24 μm to obtain coal particles. The coal particles obtained in the grinding step 30 were divided into 4-1 and 4-2, and only the coal particles 4-1 were advanced to the first molding step 40.

In the first molding step 40, flakes (first molded body 5) having an apparent density of 1.0 g / cm ³ were produced from the coal particles 4-1 using a horizontal supply type roller compactor. When the first molded body 5 obtained in the first molding step 40 is processed with a sieve mesh of 3.35 mm, the weight ratio of the first molded body 5 on the sieve to the total weight of the coal particles 4 supplied to the roller compactor is as follows. It was 90.2%, and it was found that the first molded body 5 can be produced with a higher yield than the reference example D1 using the briquette machine in the first molding step 40.

The obtained flakes (including the sieves) (first molded body 5) and the coal particles 4-2 obtained in the pulverizing step 30 are mixed at a weight ratio of 7: 3, and then the second crushing step 10a. The second crushed material 6 was obtained by crushing with a hammer rotation speed of 500 rpm. The average particle size of the obtained second crushed material 6 is 0.17 mm, and as shown in FIG. 4-6, it has an average particle size substantially equal to that of the second crushed material 6 of Reference Example D1. It has been shown.

Although the 2nd shaping | molding process 40a using the 2nd crushed material 6 obtained in Example D1 is not implemented, the 2nd crushed material 6 of Example D1 is quality equivalent to the 2nd crushed material 6 of Reference Example D1. Therefore, when the 2nd shaping | molding process 40a is performed with respect to the 2nd crushed material 6 of Example D1, it can be anticipated that the 2nd molding 7 of the quality equivalent to the reference example D1 will be obtained.

As described above, in Example D1, 30% by weight of the coal particles obtained in the pulverization step 30 is directly supplied to the second crushing step. Therefore, the processing capacity required in the first molding step 40 compared to the reference example D1. Was reduced by 30%, indicating that the load could be reduced. Further, the hammer rotation speed of the hammer crusher in the second crushing step 10a is smaller in Example D1 than in Reference Example D1, and it was shown that the load on the crusher in the second crushing step 10a can be reduced.

<< Example of Part E >>
According to Examples E1 to E3 and Comparative Example E1, quality evaluation of the obtained coal molding was performed. In Examples E1 to E3 and Comparative Example E1, as shown in FIG. 5A, the first crushing step 10, the drying step 20, the crushing step 30, the first molding step 40, the second crushing step 10a, and the second molding The coal molded body 100 is obtained through the process 40a and the sieving process 70. Tables E2 and E3 show the properties of the coal used in Examples E1 to E3 and Comparative Example E1.

 

 

(Example E1)
In this example, B coal, which is Indonesian lignite, was crushed in the first crushing step 10 so as to have an average particle diameter of 3 mm or less using a Hanmark lasher. Next, the crushed B charcoal was dried in a drying step 20 using a steam tube dryer so that the total moisture of the dried product 3 was 11.2%. In the subsequent crushing step 30, the dried B charcoal was pulverized using a roller mill so that the average particle diameter of the pulverized coal 4 was 19 μm. Next, the pulverized coal 4 obtained by the pulverization step 30 was molded in the first molding step 40.

In the first molding step 40, a vertical supply / discharge briquette machine was used as the molding machine. The briquette machine used has a pair of rolls 41 as shown in FIG. 5B. Only one of the rolls 41 has a roll pocket, and the other roll 41 has a flat outer peripheral surface with no irregularities. Had. The pair of rolls 41 had a diameter of 520 mm and an axial length of 236 mm.

The shape of the roll pocket was an almond shape having a substantially elliptical shape in plan view as shown in FIGS. 5-3A and 5-3B. On the roll 41, two types of roll pockets of shape A and shape B having different dimensions were formed. Table E4 shows the dimensions of the roll pocket.

On the peripheral surface of the roll 41, 5244 roll pockets of shape A and 184 roll pockets of form B were regularly distributed. Volume per one roll pockets, shape A is 0.035Cm ^3, shape B was 0.0048cm ^3. Further, if the gap between the rolls 41 is large, leakage of the pulverized coal 4 and pressure dispersion are likely to occur, so the gap d between the rolls 41 is set to 1 mm. Moreover, the briquette machine adjusted the rotation speed of the roll 41 and the screw so that the roll linear pressure was maintained at 1.9 t / cm.

The apparent density of the first molded body 5 obtained by the first molding step 40 was measured and found to be 1.077 g / cm ³ .

After the first molding step 40, the obtained first molded body 5 was crushed in the second crushing step 10a to obtain a second crushed product 6. In the second crushing step 10a, a hammer mark lasher was used.

Next, the second crushed material 6 was molded in the second molding step 40 a to obtain a second molded body 7. In the second molding step 40a, the same briquette machine as used in the first molding step 40 was used, and the rotation speeds of the roll 41 and the screw were adjusted so that the roll linear pressure was maintained at 7 t / cm.

After the second molding step 40a, in the sieving step 70, the pulverized coal was removed from the second molded body 7 to obtain a coal molded body 100. In the sieving step 70, sieving was performed manually using a standard sieve having an opening of 3.35 mm. The proportion on the sieve was 93.9%. Thereby, it has confirmed that the 2nd shaping | molding process 40a was drive | operated stably and the coal molding 100 was obtained with high yield.

In addition, when the physical property of the 2nd crushing thing 6 obtained by the 2nd crushing process 10a was measured, an average particle diameter is 0.40 mm, bulk density (coarse) is 0.65 g / cm < ³ >, and bulk density (dense) is. It was 0.84 g / cm ³ .

Moreover, the tapping machine was used to measure the change in tap density until the second crushed material 6 was tapped 500 times. The tap density is an apparent bulk density when a sample (which is a powder) is gently filled in a container (measuring cylinder) and then tapped and tightly packed. Tapping was performed by moving the container upward and then dropping the container freely. The stroke of the tapping machine was 20 mm, and the tapping speed was 35 times / min. Record the volume of the sample (second crushed material 6) (from the scale of the graduated cylinder) at each of the 0, 5, 10, 25, 75, 100, 250, and 500 tapping times. And the tap density in each frequency | count was calculated | required from the preparation weight. This result was applied to the above-described formula (1), and the fluidity and adhesion as the powder of the second crushed material 6 were evaluated.
Formula (1): N / C = (1 / ab) + (1 / a) N

The evaluation of fluidity was performed by the fluidity index a, and the evaluation of adhesion was performed by the adhesion index 1 / b. When these indices were determined from the tap density measurement results, the fluidity index a was 0.28 and the adhesion index 1 / b was 53.4.

(Example E2, Example E3, Comparative Example E1)
The coal molding 100 was manufactured in the same procedure as in Example E1, except that some parameters were changed from those in Example E1. The changed parameters are the total moisture of the dried product 3, the average particle diameter of the pulverized coal 4, and the roll linear pressure of the first molding step 40. By changing these parameters, various evaluation results (the yield in the second molding step 40a, the operational stability of the second molding step 40a, the apparent density of the first molded body 5, and the average of the second crushed material 6) These results, in which the particle size, bulk density, fluidity index a and adhesion index 1 / b) have changed, are shown in Table E5 together with the results in Example E1.

(Discussion)
It has been found that changing the parameters affects the operational stability and yield in the second molding step. In particular, paying attention to the characteristics of the raw material (second crushed material) in the second molding step, when a briquette machine is used, the fluidity index a of the raw material (second crushed material) is 0.29 or less and adheres. When the property 1 / b satisfies 20 ≦ 1 / b ≦ 60, it can be said that the briquette machine can be stably operated at a high yield.

<< Example of Part F >>
Examples of the invention of Part F will be described below. Table F1 shows the properties of the coal used in the examples described below.

[Example F1]
(Example F1)
Using coal coal, which is Indonesian brown coal, as a raw material coal, a coal-molded fuel 200 was manufactured according to the process shown in FIG. 6A (in order of crushing process 20 → drying process 30).

In the crushing step 10, crushed coal 2 having a maximum particle size of 1 mm and an average particle size of 0.3 mm was obtained using a Hanmark crusher. Next, in the pulverizing step 20, a pellet mill was used. The crushed coal 2 was pulverized between a roller inside the pellet mill and a ring die, further discharged continuously from the hole of the ring die, and pelletized by appropriately cutting the length. As a result, hydrous pellets (8 mm diameter × cylindrical shape having a height of 10 to 20 mm) composed of pulverized coal 3 having an average particle diameter of 10 μm were obtained.

In the drying step 30, in order to improve the drying efficiency, the water-containing pellets were crushed so as to have a maximum particle size of 3 mm or less using a paddle mixer before drying. After crushing the water-containing pellets, a steam tube dryer was used and dried so that the total water content was 15%. Thus, dried coal particles 4 were obtained. The temperature of the obtained coal particles 4 was 90 ° C.

During the period from the drying step 30 to the molding step 40, a heat insulating material was installed in the conveying device from the outlet of the drying step 30 to the inlet of the molding step 40 so that the temperature of the coal particles 4 was maintained at 90 ° C. When the temperature of the coal particle 4 was measured with the thermometer installed in the inlet of the shaping | molding process 40, it was confirmed that it is 90 degreeC.

In the molding step 40, a vertical supply briquette machine as shown in FIG. 6-2 was used. The briquette machine used had a pair of rolls 41 with a diameter of 520 mm and a width (length in the axial direction) of 124 mm. On the peripheral surfaces of the pair of rolls 41, a plurality of roll pockets having the shapes shown in FIGS. 6-2A and 2B are regularly distributed. The dimensions of each part of the roll pocket are
a = 34.7 mm
b = 36.6 mm
c = 9.1 mm
Met. The gap d between the pair of rolls 41 was 1 mm, which is a design lower limit value. The operation of the briquette machine was controlled so that the linear pressure by the roll 41 was 6 t / cm, and thus the molded body 5 was obtained.

The obtained molded body 5 was supplied to the sieving step 70, and the coal powder was removed in the sieving step 70. In the sieving process 70, a vibrating sieve machine having a sieve mesh of 3.35 mm was used, and the coal remaining on the sieve was used as the coal molding fuel 200.

(Comparative Example F1)
As Comparative Example F1, a coal molded fuel 200 was manufactured in the same manner as in Example F1 except that the temperature of the coal particles 4 supplied to the molding process 40 was changed. Specifically, the coal particles 4 were cooled by a conveying device from the outlet of the drying step 30 to the inlet of the molding step 40 so that the temperature of the coal particles 4 supplied to the molding step 40 was 25 ° C. . As the transport device, a screw-type transport device with a water-cooled jacket was used, and the residence time was controlled by the rotational speed of the transport paddle to adjust the temperature of the coal particles 4. As a result of measuring the temperature of the coal particles 4 with a thermometer installed at the entrance of the molding step 40, it was confirmed to be 25 ° C.

(Evaluation 1)
Quality evaluation was performed about the coal molding fuel 200 obtained by Example F1 and Comparative Example F1. Table F2 shows typical physical properties of the coal particles 4, typical typical molding conditions and molding capability of the molding step 40, and quality evaluation results of the obtained coal molded fuel 200.

In Table F2, the crushing strength of the coal-molded fuel 200 was measured based on “3.1 Crushing strength test method” of JIS Z 8841-1993. The apparent density was measured based on “8. Measuring method of density and specific gravity by submerged weighing method” of JIS Z 8807.

From Table F2, Example F1 shows that the total moisture and particle size distribution of the coal particles 4 are equivalent to those of Comparative Example F1, but the temperature of the coal particles 4 at the inlet of the molding step 40 is 90 ° C. It can be seen that the crushing strength almost doubled compared to Comparative Example F1 in which the temperature of the coal particles 4 at 40 inlets was 25 ° C. From this, by setting the temperature of the coal particles 4 at the entrance of the molding step 40 to 90 ° C., in other words, by molding the coal particles 4 at 90 ° C., the crushing strength is high and the handling property is excellent. It can be said that the coal-molded fuel 200 can be manufactured.

[Examples F2 and 3]
(Example F2-1)
BM1 coal, Indonesian brown coal, was used as the raw material coal, and a coal-molded fuel 200 was manufactured according to the process shown in FIG. 6-1, except that the sieving process 70 was not performed (however, the drying process 30 → the pulverization process) 20 order).

The crushing process 10 was implemented similarly to Example F1. Next, in the drying step 30, the crushed coal 2 was dried using a steam tube dryer so that the total water content was 10 to 15%, thereby obtaining dry coal 3 '. Next, in the pulverizing step 20, the dry coal 3 ′ was pulverized using a ball mill so that the average particle size was 20 to 30 μm, whereby coal particles 4 were obtained.

Next, the obtained coal particles 4 were supplied to the molding step 40 to obtain a molded body 5. In the molding step 40, a temperature-adjustable tablet machine having a pair of pressure plates 401, 402, a pair of molds 403, 404 and a heater built in the pressure plates 401, 402 as shown in FIG. Using. Each of the molds 403 and 404 constituted a core mold and a cavity mold, and the cavity mold (404) had a cylindrical cavity having an inner diameter of 14 mm. In the tablet machine used, the upper pressure plate 401 is a fixed compression plate and the lower pressure plate 402 is a movable compression plate, and the powder in the cavity 406 is compressed and molded by raising the lower pressure plate 402. It has a structured structure.

First, with the molds 403 and 404 opened, the temperatures of the molds 403 and 404 were measured by a thermocouple 407 for measuring the mold temperature, and when the temperature reached 60 ° C., the coal particles 4 were put into the cavity 406. After charging the coal particles 4, the molds 403 and 404 were closed, and a thermocouple 408 for measuring the raw material temperature was advanced into the cavity 406 to measure the temperature of the coal particles 4.

When the temperature measured by the thermocouple 408 for measuring the raw material temperature, that is, when the temperature of the coal particles 4 reaches 60 ° C., the thermocouple 408 is retracted, and then the pressure plate 402 is raised, and the coal particles in the cavity 406 4 was compression molded. The compression molding conditions were a molding pressure of 1.9 t / cm ² , a pressing time of 1 minute, and a holding time under pressure of 1 minute. Here, “pressurization time” refers to the time from the start of pressurization until reaching the molding pressure, and “holding time under pressure” refers to the time during which the molding pressure is maintained after reaching the molding pressure. Say.

After compression molding, the molds 403 and 404 were opened to take out the tablet-shaped (columnar) molded body 5, which was used as the coal-molded fuel 200.

(Example F2-2)
A coal-molded fuel 200 was obtained in the same manner as in Example F2-1 except that the temperature of the coal particles 4 during compression molding was set to 80 ° C.

(Comparative Example F2)
A coal-molded fuel 200 was obtained in the same manner as in Example F2-1 except that the temperature of the coal particles 4 during compression molding was 20 ° C.

(Example F3-1)
A coal-molded fuel was obtained in the same manner as in Example F2-1 except that RM coal, which is Indonesian lignite, was used as the raw material coal 1.

(Example F3-2)
A coal-molded fuel 200 was obtained in the same manner as in Example F2-2, except that RM coal, which is Indonesian lignite, was used as the raw material coal 1.

(Comparative Example F3-1)
A coal-molded fuel 200 was obtained in the same manner as in Comparative Example F2, except that RM coal, which is Indonesian lignite, was used as coal 1 as a raw material.

(Comparative Example F3-2)
A coal-molded fuel 200 was obtained in the same manner as in Comparative Example F3-1 except that the temperature of the coal particles 4 during compression molding was 40 ° C.

(Evaluation)
The tablet-shaped coal molded fuel 200 obtained in each of the above examples and comparative separation was left in the atmosphere for 3 minutes and then stored in a sample bag with a zipper. The coal molded fuel 200 was subjected to quality evaluation on a sample immediately after molding (immediately after being taken out of the mold) and on a sample stored in a sample bag after one day. Table F3 shows typical physical properties of the coal particles 4, typical molding conditions of the molding step 40, and quality evaluation results of the obtained coal molded fuel 200.

In Table F3, the tensile strength of the coal-molded fuel 200 is obtained by using the fixed compression plate 501 and the movable compression plate 502 as shown in FIG. 6-6 used in “3.1 Crushing strength test method” of JIS Z 8841-1993. A testing machine having was used. Prior to the test, the diameter d (mm) and the height L (mm) of the coal-molded fuel 200 as a sample were measured with calipers or the like. Next, the coal-molded fuel 200 was installed in the central portion of the fixed compression surface 501a of the fixed compression plate 501 in the posture shown in FIG. 6-6. In this state, the movable compression platen 502 was lowered at 10 mm / min, and a load was applied to the coal molded fuel 200. The maximum indicated value of the load until the coal molded fuel 200 was completely destroyed was recorded, and this was used as the crushing strength P (N) of the coal molded fuel 200. The tensile strength was calculated by the following formula using the obtained crushing strength.

The apparent density was measured based on JIS Z 8807 "8. Method for measuring density and specific gravity by submerged weighing method". The total moisture was measured by measuring the weight of the sample at each time point on the premise that the charged dry weight was unchanged, and calculating the total moisture by the following formula (2).
_{(W t1 -w load × (1} -m 0/100)) / w t1 × 100 ··· formula (2)
Here, w _t1 is the weight of the sample when a predetermined time elapses, w _load is the wet weight of the charged raw material, and m ₀ is the total moisture of the raw material immediately before molding.

Fig. 6-7 shows the relationship between molding process inlet temperature and tensile strength, and Fig. 6-8 shows the relationship between molding process inlet temperature and apparent density.

From the above results, in the coal molded fuel 200 manufactured under conditions where the total water content and particle size distribution are almost constant, the higher the temperature, the higher the tensile strength and the coal molded fuel 200 in the molding process inlet temperature range of 20-80 ° C. It was found that the apparent density was increased. By increasing the tensile strength and the apparent density, it is possible to obtain the coal-molded fuel 200 having excellent handling properties. This tendency is the same even if the brand of coal 1 as a raw material is different.

[Example F4]
(Example F4-1)
Except for the following points, a coal-molded fuel 200 was obtained in the same manner as in Example F2-1.
(A) As coal 1, BM2 coal which is lignite from Indonesia was used.
(B) In the crushing step 10, the coal crusher 10 and the double roll crusher were processed in this order to crush the coal 1 so that the average particle diameter was 3 mm or less.
(C) In the drying step 30, the crushed coal 2 was dried using a steam tube dryer so that the total moisture was 23%.
(D) The tablet machine used in the molding step 40 had a cylindrical cavity having an inner diameter of 20 mm.
(E) In the molding step 40, the temperature of the coal particles 4 during compression molding was set to 115 ° C.
(F) In the molding step 40, the molding pressure was 1 t / cm ² .

(Example F4-2)
A coal-molded fuel 200 was obtained in the same manner as in Example F4-1 except that the temperature of the coal particles 4 during compression molding was 130 ° C.

(Example F4-3)
A coal-molded fuel 200 was obtained in the same manner as in Example F4-1 except that the total water content of the coal particles 4 at the outlet of the drying process was 17.0%.

(Comparative Example F4)
The coal-molded fuel 200 is the same as in Example F4-1 except that the total water content of the coal particles 4 at the outlet of the drying process is 16.0% and the mold is not heated in the molding process 40 (20 ° C.). Got.

(Evaluation)
Quality evaluation was performed on the tablet-shaped coal molded fuel 200 obtained in each of the above Examples and Comparative Examples. The quality evaluation is performed immediately after the coal-molded fuel 200 is taken out from the mold, and left in the atmosphere for 10 minutes after being taken out of the mold, and then stored in a sample bag with a zipper, and after one day has passed, Samples for evaluation were prepared for the time points. Table F4 shows typical physical properties of the coal particles 4, typical typical molding conditions of the molding step 40, and quality evaluation results of the obtained coal molded fuel 200.

In Table F4, the total moisture and apparent density were determined in the same manner as in the evaluations in Examples F2 and 3. As for the immersion moisture, the measurement sample is immersed in water, the sample is collected after 7 days from the start of immersion, the moisture adhering to the surface is removed with a cloth such as a waste cloth, and then JIS M 8820-0. Measurement was made based on the total moisture measurement method for coals described in (Coal and coke-lot total moisture measurement method), and the value was defined as immersion moisture.

From Table F4, it was confirmed that in all of the examples and comparative examples, the total water content decreased immediately after molding until one day later. As for the apparent density, it was confirmed that the comparative example decreased in the comparative example, but increased in each example, immediately after molding until one day later. From this, it can be seen that in each example, when one day has passed immediately after molding, the total moisture has decreased, and thus the coal-molded fuel 200 contracts. Further, as for the immersion moisture, it was impossible to measure the immersion moisture immediately after molding in the comparative example, but it was confirmed that the immersion moisture decreased between immediately after molding and after 1 day in each example. Lowering the immersion moisture means that the water resistance is improved. In the comparison of Example F4-1 and Example F4-2, there was no significant difference in the value of immersion moisture between the case of molding at 115 ° C. and the case of molding at 130 ° C. However, these Example F4-1 and Example F4-2 have significantly smaller immersion moisture (after one day) than Comparative Example F4. Therefore, by heat-molding the coal particles 4, the water resistance is excellent. It can be said that the coal-molded fuel 200 can be manufactured.

[Example F5]
(Example F5-2)
Except for the following points, a coal-molded fuel 200 was obtained in the same manner as in Example F2-1.
(A) In the crushing step 10, the coal 1 was processed in the order of a jaw crusher and a double roll crusher, and the coal 1 was crushed so that the average particle diameter was 3 mm or less.
(B) In the drying step 30, four types of dry coal 3 ′ having different total moisture were obtained by adjusting the drying time using a box-type dryer. The obtained dry coal 3 ′ was pulverized in the pulverization step, and coal particles 4 having a total water content of 11.1 to 17.5% were converted into (Example F5-2-1) to (Example F5-2-4). ).
(C) In the molding step 40, the molding pressure was 1.95 t / cm ² .

(Example F5-3)
Except that the temperature of the coal particles 4 at the time of compression molding was set to 80 ° C., four types of coal-molded fuels 200 were obtained from the coal particles 4 having different total water contents (Example F5- 3-1) to (Example F5-3-4)).

(Example F5-4)
Except that the temperature of the coal particles 4 at the time of compression molding was set to 95 ° C., four types of coal-molded fuels 200 were obtained from the coal particles 4 having different total water contents (Example F5- 4-1) to (Example F5-4-4)).

(Comparative Example F5-1)
In the same manner as in Example F5-2, except that the temperature of the coal particles 4 at the time of compression molding was 30 degrees and the total moisture was 10.5 to 17.5%, five types of coal particles 4 having different total moisture were used. A coal-molded fuel 200 was obtained ((Comparative Example F5-1-1) to Comparative Example F5-1-5)).

(Evaluation)
Quality evaluation was performed on the tablet-shaped coal molded fuel 200 obtained in each of the above Examples and Comparative Examples. The quality evaluation was performed after taking out the coal-molded fuel 200 from the mold and leaving it in the atmosphere for 5 minutes, and then storing it in a sample bag with a zipper after one day. Tables F5 to F8 show typical physical properties of the coal particles 4, typical typical molding conditions of the molding step 40, and quality evaluation results of the obtained coal molded fuel 200.

In Tables F5 to F8, total moisture, immersion moisture, and apparent density were determined in the same manner as in the evaluation in Example F4. In addition, FIG. 6-9 is a graph showing the relationship between the total moisture and the immersion moisture shown in Tables F5 to F8.

From FIG. 6-9, the immersion moisture decreases as the temperature of the coal particles 4 at the time of molding increases. From this, the water resistance of the obtained coal-molded fuel 200 increases as the temperature of the coal particles 4 at the time of molding increases. It can be seen that can be further improved.

Claims (23)

Crushing process of crushing coal;
A drying step of drying the coal crushed in the crushing step;
A pulverizing step of pulverizing the coal dried in the drying step to obtain coal particles;
Molding the coal particles obtained in the pulverization step into a plate shape, and a molding step for obtaining an intermediate molded body including a molded body;
A sieving step for removing the powder contained in the intermediate molded body obtained in the molding step;
Have
The coal particles obtained in the pulverization step have an average particle size of 10 to 60 μm,
A method for producing a coal-molded fuel, characterized in that the molded body obtained in the molding step and from which the powder has been removed in the sieving step is used as a coal-molded fuel. In the manufacturing method of the coal molding fuel of Claim 1,
Using a supply means to supply the coal particles from the grinding step to the molding step;
The method for producing a coal-molded fuel, wherein the supply means is a screw-type supply means. In the manufacturing method of the coal molding fuel of Claim 1 or 2,
A method for producing a coal-molded fuel, characterized in that no binder is added. In the manufacturing method of the coal molding fuel as described in any one of Claim 1 to 3,
The molding step includes supplying the coal particles between two rotating rolls;
The method for producing a coal-molded fuel, wherein at least one surface of the two rolls has irregularities. In the manufacturing method of the coal molding fuel of Claim 4,
A clearance between the two rolls is 3 mm or less. In the manufacturing method of the coal molding fuel as described in any one of Claim 1 to 5,
When the crushing step is the first crushing step and the molding step is the first molding step,
After the first molding step, a second crushing step of crushing the intermediate molded body that is the plate-like molded body obtained in the first molding step;
After the second crushing step, a second molding step of molding the intermediate molded body again;
Further comprising
A method for producing a coal-molded fuel, wherein a horizontal supply type compactor is used at least in the first molding step. A coal-molded fuel obtained from a coal-particle shaped body,
The coal particles have an average particle size of 10 to 60 μm,
The moisture is 5 to 20 wt%, the apparent density is 1.2 to 1.4 g / cm ³ , the bulk density is 0.4 to 0.6, and
A first fracture piece having two types of surfaces, a smooth surface to which a smooth molding surface is transferred, and a fracture surface;
A second fractured piece having two types of surfaces, an irregular surface to which a molding surface having irregularities is transferred, and a fracture surface;
A third fracture piece having three types of surfaces, the smooth surface, the irregular surface, and the fracture surface;
The surface is a fourth fracture piece with only a fracture surface,
A coal-molded fuel characterized by being a mixture of one or more of the above. In the coal-molded fuel according to claim 7,
The third broken fragment is
A 3A fracture piece in which the smooth surface and the uneven surface face each other;
The smooth surface and the uneven surface are adjacent in the same plane, and the opposing surface is a 3B fracture fragment, which is a fracture surface;
Have
A coal-molded fuel characterized in that a thickness of the smooth surface and the uneven surface in the 3A fracture fragment is 4.0 to 13.0 mm. In the coal-molded fuel according to claim 7,
The first fragment is
A 1A fracture piece in which the smooth surfaces face each other;
A 1B fracture piece whose opposing surface of the smooth surface is the fracture surface;
And the thickness of the smooth surfaces in the 1A fracture piece is 2 to 10 mm. A method for curing modified coal that retains modified coal under predetermined curing conditions,
The predetermined curing conditions are a temperature of -5 to 40 ° C., a relative humidity of 5 to 95%, and a modified coal curing method characterized by being 200 days or longer. The method for curing modified coal according to claim 10,
When the water immersion moisture modified coal before curing _{W A,} the immersion in water moisture modified coal after curing and _{W B,} characterized in that it is a _{W B / W A = 0.70 ~} 0.90 Curing method for modified coal. In the curing method of the modified coal according to claim 10 or 11,
The modified coal is a molded body obtained by compression molding the coal particles, the compression direction thickness of the modified coal before curing T _A, the compression direction thickness of the modified coal after curing and T _B Then, T _B / T _A = 1.0 to 1.2. The method for curing reformed coal according to any one of claims 10 to 12,
The modified coal is obtained by molding coal particles,
The coal particles have an average particle size of 10 to 60 μm and a water content of 5 to 20%,
A method for curing modified coal, wherein the apparent density of the modified coal before curing is 1.2 to 1.4 g / cm ³ . A method for curing modified coal that retains modified coal under predetermined curing conditions,
The method for curing modified coal, wherein the predetermined curing conditions are a temperature of 60 to 120 ° C. and a time of 15 to 60 minutes. The method for curing modified coal according to claim 14,
_A method for curing modified coal, characterized in that W _B / W _A = 0.60 to 0.95, where W _A is water immersed in water before curing, and W _B is water immersed in water after curing. In the curing method of the modified coal according to claim 14 or 15,
Water immersion expansion of pre-cured _{E A,} when the _{E B} the water immersion expansion coefficient after _curing, curing method of modified coal, which is a _{E B / E A = 0.60 ~} 0.99 . The method for curing reformed coal according to any one of claims 14 to 16,
The reformed coal is formed coal obtained by compression molding of coal particles, and TA / TA = 1.000 or more when TA is the thickness in the compression direction before curing and TB is the thickness in the compression direction after curing. A method for curing modified coal, which is 1.025. The method for curing modified coal according to any one of claims 14 to 17,
The modified coal is obtained by molding coal particles,
The coal particles have an average particle size of 10 to 60 μm and a water content of 5 to 20%,
A method for curing modified coal, wherein the apparent density of the modified coal before curing is 1.20 to 1.40 g / cm ³ . A first crushing step of crushing coal;
A drying step of drying the coal crushed in the first crushing step;
Crushing the coal dried in the drying step to obtain coal particles having an average particle size of 10 to 60 μm;
A first molding step of molding the coal particles having a water content of 5 to 20 wt% to obtain a first molded body;
A second crushing step of crushing the first molded body to generate a second crushed material;
A second molding step of molding the second crushed material again to produce a second molded body having an apparent density of 1.2 to 1.4 g / cm ³ ;
A method for producing a coal-molded fuel having
In the first molding step, a horizontal supply type molding machine is used. A method for producing a coal-molded fuel according to claim 19,
Supplying a part of the coal particles obtained in the crushing step to the second crushing step without going through the first molding step;
In the second crushing step, the first molded body and a part of the coal particles are mixed and crushed. A method for producing a coal molded body molded by a vertical supply / discharge molding machine that molds coal particles supplied from vertically above and discharges the molded coal molded body vertically downward,
The coal particles have an initial volume per unit weight of Vo, a volume at the time of tapping N times as V _N , and a degree of bulk reduction as C = (Vo−V _N ) / Vo.
Formula (1): N / C = (1 / ab) + (1 / a) N
In
Condition (1): a ≦ 0.29
Condition (2): 20 ≦ 1 / b ≦ 60
A method for producing a coal molding characterized by satisfying any of the above. In the manufacturing method of the coal molding according to claim 21,
A first crushing step of crushing coal;
A drying step of drying the coal crushed in the first crushing step;
Crushing the coal dried in the drying step to obtain pulverized coal;
A first molding step of molding the pulverized coal to obtain a first molded body;
A second crushing step of crushing the first molded body to generate a lump,
A second molding step for re-molding the mass and generating a second molded body;
Have
The lump is an aggregate of the pulverized coal, corresponding to the coal particles,
In the second molding step, the vertical supply / discharge molding machine is applied,
A method for producing a coal molding characterized by the above. In the manufacturing method of the coal molding according to claim 22,
The pulverized coal has an average particle size of 10 to 60 μm and a total water content of 5 to 20 wt%.
The apparent density of the second molded body is 1.2 to 1.4 g / cm ³ ;
A method for producing a coal molding characterized by the above.

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