WO2021221163A1 - Biomass gasification device - Google Patents

Abstract

A biomass gasification device equipped with: a preheater 10 which preheats a heat carrier medium 30; a thermal decomposition device 20 which receives the supply of the heat carrier medium 30 that has been preheated with the preheater 10 and performs the thermal decomposition of a biomass with heat of the heat carrier medium 30; a thermally decomposed gas reformer 40 which at least partially combusts a thermally decomposed gas generated as the result of the thermal decomposition with air or oxygen; and a supply mechanism which is arranged between the preheater 10 and the thermal decomposition device 20 and is configured to supply the heat carrier medium 30 from the preheater 10 to the thermal decomposition device 20. The supply mechanism has: an opening/closing unit for storing the heat carrier medium 30 temporality; and a regulation unit which is arranged below the opening/closing unit and can be slid to supply the heat carrier medium 30 supplied from the opening/closing unit to the thermal decomposition device 20.

Description

Biomass gasifier

The present invention relates to a biomass gasifier having a preheater, a pyrolyzer and a pyrolyzed gas reformer.

As a gasifier for high ash biomass, for example, sewage sludge having an ash content of 20% by weight is dried and then pyrolyzed in an air-blown fluidized layer pyrolysis furnace at 500 to 800 ° C. to pyrolyze the pyrolysis gas. A method of generating turbine power by burning with air at a high temperature of 1000 to 1,250 ° C and generating steam with the heat (Japanese Patent Laid-Open No. 2002-322902), high ash biomass as a raw material is circulated by air blowing. Pyrolysis is carried out in a flow heating furnace at a temperature of 450 to 850 ° C., and char, which is a thermal decomposition residue, is recovered by a cyclone, while pyrolysis gas containing tar is reformed at 1000 to 1200 ° C. in the presence of oxygen. Method (Japanese Unexamined Patent Publication No. 2004-51745), in order to prevent sticking of the flow medium, the char is pyrolyzed by the same method to separate the char, and then the char is granulated and supplied into the circulating flow reforming furnace. A method of producing a granulated sintered body by sintering at a temperature of 900 to 1000 ° C. (Japanese Patent No. 4155507) or the like is disclosed.

Further, a heat-carrying medium for carrying heat, a preheater for heating the heat-carrying medium, a reformer for steam reforming of the heat-decomposed gas, and a heat-decomposing wood biomass raw material. The preheater, the reformer, and the heat decomposer 20 are provided with a heat decomposer, a separator for separating the heat-bearing medium and the char, and a hot air furnace that burns the char to generate hot air. , Devices arranged vertically in order from the top are known (Japanese Patent Laid-Open No. 2011-144329).

Further, it is characterized in that it is basically provided with a pyrolyzer in the pyrolysis zone and a gas reformer in the reaction zone separately and independently, so that both a series connection type and a parallel connection type can be configured. A device to do so has also been proposed. Immediately after the heat-bearing medium has passed through a heating zone of about 1100 ° C., a reaction zone of 950 to 1000 ° C., a thermal decomposition zone of 550 to 650 ° C., and a separation step, and then returns to the heating zone and exits the thermal decomposition reactor. , The heat-decomposed coke obtained by separating the mixture consisting of the heat-decomposed coke and the heat-bearing medium is burned in a combustion device, and the heat-bearing medium is heated in the heating zone by utilizing the apparent heat generated thereby. , An embodiment of producing a product gas having a high calorific value from an organic substance and a substance mixture (Japanese Patent No. 4264525) is known.

Further, a pyrolysis gas introduction tube for introducing the pyrolysis gas from the pyrolysis device to the pyrolysis gas reformer is formed on the pyrolysis device side on the upper surface of the preheated heat-bearing medium layer formed in the pyrolysis device. A gasification method (Japanese Patent Laid-Open No. 2019-65160) installed on the side surface of a lower pyrolyzer is known.

In the gasification method as described above, which is provided with a preheater, a pyrolyzer and a gas reformer and utilizes the heat of the heat-bearing medium heated by the preheater, the heat-supporting heat is carried by hot air in the preheater. The medium is dropped into a pyrolyzer and mixed with biomass such as wood chips to generate biogas.

Japanese Patent Application Laid-Open No. 2019-65160 uses a so-called two-stage valve system in which a total of two valves are provided, one on the top and one on the bottom of the pipe.

When this two-stage valve system is adopted, a plurality of heat-supporting media are supplied to the pyrolyzer in a mass. Further, since it takes time for the valve group to open and close once, the heat carrier is supplied intermittently. For example, gasification proceeds well immediately after the heat-supporting medium falls into the pyrolyzer, but gasification does not proceed much until the next heat-supporting medium falls into the pyrolyzer. As a result, the pressure of the pyrolyzer fluctuates. In addition, the pressure fluctuates even when the valve is opened and closed. For this reason, air may enter from the supply port of wood chips or the like, or vice versa, biogas may leak. In addition, the composition and flow rate of the gas are not stable when gasification progresses and when it does not progress, and gas of constant quality is not generated, which hinders the separation performance of the device that separates the components in the gas installed in the subsequent stage. There can also be a problem of becoming a factor.

The biomass gasifier according to the present invention
A preheater that preheats the heat-supporting medium and
A thermal decomposer that receives a supply of a heat-bearing medium preheated by the preheater and executes thermal decomposition of biomass by the heat of the heat-bearing medium.
A pyrolysis gas reformer that at least partially burns the pyrolysis gas generated by pyrolysis with air or oxygen.
A supply mechanism provided between the preheater and the pyrolyzer for supplying the heat-carrying medium from the preheater to the pyrolyzer, and
With
The supply mechanism
An opening / closing part for temporarily storing the heat-carrying medium and
An adjusting unit provided below the opening / closing unit and supplying the heat-carrying medium supplied from the opening / closing unit to the pyrolyzer by swinging or rotating.
May have.

In the biomass gasification device according to the present invention
The opening / closing portion has a first opening / closing portion and a second opening / closing portion provided below the first opening / closing portion.
A control device may be provided which opens the first opening / closing portion while the second opening / closing portion is closed and opens the second opening / closing portion while the first opening / closing portion is closed.

In the biomass gasification device according to the present invention
Each of the first opening / closing part and the second opening / closing part may be a damper valve.

The biomass gasifier according to the present invention
A hopper provided between the preheater and the pyrolyzer,
A control device that controls the supply of the heat-supporting medium from the preheater to the pyrolyzer based on the weight or top surface position of the heat-supporting medium in the hopper.
May be provided.

In the biomass gasification device according to the present invention
The adjusting portion may be a swing valve or a rotary valve.

In the biomass gasification device according to the present invention
A steam atomizer that sprays steam between the preheater and the pyrolyzer when the opening / closing portion is in the open state may be provided.

In the biomass gasification device according to the present invention
The adjusting part is composed of a swinging part.
A control device for controlling the supply amount of the heat-carrying medium to the pyrolyzer may be provided by changing the swing cycle time or the swing distance of the swing portion.

In the biomass gasification device according to the present invention
The adjusting part is composed of a rotating part.
The control device may control the supply amount of the heat-carrying medium to the pyrolyzer by changing the rotation speed of the rotating portion.

In the biomass gasification device according to the present invention
A third valve provided below the pyrolyzer and
A steam atomizer that sprays steam when the third valve is in the open state may be provided.

In the present invention, the supply mechanism is provided at the opening / closing part for temporarily storing the heat-carrying medium and below the opening / closing part, and the heat-carrying medium supplied from the opening / closing part is thermally decomposed by swinging or rotating. When an embodiment having an adjusting unit for supplying to the vessel is adopted, gasification can be performed in a stable amount.

FIG. 1 is a schematic view showing an embodiment of a biomass gasification device. FIG. 2 is a diagram showing a method of supplying a heat-carrying medium from a preheater to a pyrolyzer in a biomass gasifier. FIG. 3A is a diagram for explaining the supply of the heat-carrying medium from the preheater through the pyrolyzer in the biomass gasifier. FIG. 3B is a diagram in which the state is advanced from FIG. 3A. FIG. 3C is a diagram in which the state is advanced from FIG. 3B. FIG. 3D is a diagram in which the state is advanced from FIG. 3C. FIG. 4 is a schematic view showing one embodiment of the supply control method in the biomass gasification device of the present embodiment. FIG. 5 is a schematic view showing one embodiment of the supply control method in the biomass gasification device of the present embodiment. FIG. 6 is a schematic view showing one embodiment of the supply control method in the biomass gasification device of the present embodiment. FIG. 7 is a schematic view showing one embodiment of the supply control method in the biomass gasification device of the present embodiment. FIG. 8 is a schematic view showing an embodiment of a control device in the biomass gasification device of the present embodiment. FIG. 9 is a side view of the rotary valve used in this embodiment. FIG. 10 is a schematic view for explaining a control mode of the heat-carrying medium in the hopper.

As shown in FIG. 1, the biomass gasifier of the present embodiment receives heat from the preheater 10 that preheats the heat-bearing medium 30 and the heat-supporting medium 30 that has been preheated by the preheater 10. A thermal decomposition device (biomass thermal decomposition device) 20 that executes thermal decomposition of biomass by the heat of the supporting medium 30 and a thermal decomposition gas generated by the thermal decomposition are partially burned by air or oxygen to execute steam reforming. It has a thermal decomposition gas reformer 40 and a supply mechanism provided between the preheater 10 and the thermal cracker 20 for supplying the heat-bearing medium 30 from the preheater 10 to the thermal cracker. There is.

The heat-supporting medium 30 (also referred to as "heat carrier") is a plurality of granules and / or lumps, preferably made of one or more materials selected from the group consisting of metals and ceramics. The metal is preferably selected from the group consisting of iron, stainless steel, nickel alloy steel, and titanium alloy steel, and more preferably stainless steel. The ceramic is selected from the group consisting of alumina, silica, silicon carbide, tungsten carbide, zirconia and silicon nitride, and more preferably alumina.

The shape of the heat-supporting medium 30 is preferably spherical (ball), but it does not necessarily have to be a true sphere, and it may be a spherical object having an elliptical or oval cross-sectional shape. The diameter (maximum diameter) of the spherical object is preferably 3 to 25 mm, more preferably 8 to 15 mm. Exceeding the above upper limit (25 mm) may impair the fluidity inside the pyrolyzer 20, that is, the free fall property, which causes the spherical object to stand still inside the pyrolyzer 20 and cause blockage. May become. On the other hand, if it is less than the above lower limit (3 mm), the spheroids themselves may stick to the spheroids due to tar and soot and dust adhering to the spheroids in the pyrolyzer 20, which may cause blockage. For example, if the diameter of the spherical object is less than 3 mm, the spherical object adheres to the inner wall of the pyrolyzer 20 and grows due to the influence of tar and dust adhering to the spherical object, and in the worst case, the pyrolyzer There is a concern that 20 will be blocked. Further, when the spherical object to which tar is attached is extracted from the valve at the bottom of the pyrolyzer 20, the spherical object having a thickness of less than 3 mm is light, and since the tar is attached, it does not fall naturally and sticks to the inside of the valve. May promote obstruction.

The biomass of this embodiment means a so-called biomass resource. Here, the biomass resource refers to plant-based biomass, for example, agricultural products such as thinned wood, sludge waste, pruned branches, forest land residue, unused trees, etc., which are discarded from agriculture, and vegetable residues and fruit tree residues, which are discarded from agriculture. , Rice straw, wheat straw, rice husks, etc., other marine plants, construction waste wood, etc .; biological biomass, for example, biological waste such as livestock excrement and sewage sludge; And so on. The apparatus of this embodiment is preferably suitable for gasification of plant-based biomass and biological-based biomass. Among them, high ash biomass having an ash content of preferably 5.0% by mass or more, more preferably 10.0 to 30.0% by mass, and further preferably 15.0 to 20.0% by mass on a drying basis. In particular, it is suitable for gasification of sewage sludge and livestock excrement.

The heat-supporting medium 30 preheated by the preheater 10 is supplied from the preheater 10 to the pyrolyzer 20 via a valve described later by free fall. In the pyrolyzer 20, the heat-supporting medium 30 causes thermal decomposition of the biomass supplied into the pyrolyzer 20 by its own heat. The heat-supporting medium 30 in the pyrolyzer 20 is discharged from the pyrolyzer 20 by free fall via a valve, and is preferably recirculated to the preheater 10.

In the configuration shown in FIG. 4, a first valve 50, a hopper 60, and a second valve 70 are provided between the preheater 10 and the pyrolyzer 20 downward from the preheater 10. The supply mechanism is openable and closable, and has an opening / closing part for temporarily storing the heat-carrying medium and a heat-bearing medium provided below the opening / closing part, which is shaken or rotated to thermally decompose the heat-carrying medium supplied from the opening / closing part. It has a second adjusting unit that supplies the vessel. When the opening / closing portion is in the closed state, the heat-carrying medium is placed above the opening / closing portion and is temporarily stored. In the configuration shown in FIG. 4, the opening / closing part is composed of the first opening / closing part and the second opening / closing part (the first damper valve 51a and the second damper valve 51b described later) of the first valve 50, and the second adjusting part is from the second valve 70. It has become.

The weight or top surface position of the heat-carrying medium 30 in the hopper 60 was monitored, and the operations of the first valve 50 and the second valve 70 were controlled based on the monitoring result, and the heat decomposer 20 was passed from the preheater 10. A control device 100 that controls the supply of the heat-carrying medium 30 may be provided. When such a control device 100 is adopted, it enables stable continuous supply of the heat-bearing medium 30 in the gasification device, stabilization of the pressure fluctuation of the pyrolyzer 20, and improvement of the separation ability in gas separation. Further, it is possible to provide a gas having stable quality.

The first valve 50 may have a first adjusting portion, a first opening / closing portion provided below the first adjusting portion, and a second opening / closing portion provided below the first opening / closing portion. .. Then, the control device 100 controls so that the first opening / closing portion is opened while the second opening / closing portion is closed and the second opening / closing portion is opened while the first opening / closing portion is closed. Therefore, it may be possible to prevent the gas on the upper side and the gas on the lower side of the first valve 50 from being mixed. Each of the first opening / closing part and the second opening / closing part may be a damper valve. Hereinafter, the embodiment in which the first opening / closing portion is the first damper valve 51a and the second opening / closing portion is the second damper valve 51b will be described. Further, the embodiment in which the first adjusting portion of the first valve 50 is the swing valve 52 will be described. Further, a mode in which the second adjusting portion of the second valve 70 is a swing valve 72 or a rotary valve 74 will be described.

In the present embodiment, in the method of supplying the heat-bearing medium 30 of the biomass gasifier, the swing valve 52 swings (see FIGS. 3A to 3D) in order to drop the heat-bearing medium 30 into the pyrolyzer 20. A method is adopted in which the heat-bearing medium 30 is dropped into the pyrolyzer 20 by a free drop in combination with the opening and closing of the damper valve 51.

To briefly explain the operation of the two-stage valve system, the upper and lower two first damper valves 51a and the second damper valve 51b are closed (FIG. 3A), the first damper valve 51a is opened, and the heat-supporting medium 30 is placed inside the pipe. It is dropped and the heat-supporting medium 30 is filled between the second damper valve 51b and the first damper valve 51a (FIG. 3B). Next, by closing the first damper valve 51a (FIG. 3C) and opening the second damper valve 51b, the heat-carrying medium 30 filled between the first damper valve 51a and the second damper valve 51b is introduced into the pyrolyzer 20. , Or discharged from the pyrolyzer 20 (Fig. 3D). By repeating such a valve operation, the heat-supporting medium 30 is introduced into the pyrolyzer 20 and discharged from the pyrolyzer 20. By adopting such a mechanism, it is possible to prevent the high-temperature gas for heating the heat-carrying medium 30 from being mixed with the gas produced by biomass (mixed gas containing hydrogen, methane, carbon monoxide, etc.). ..

The swing valve 52 is a valve suitable for stopping the flow by moving like a pendulum while the solid is flowing downward, but it does not have a gas sealing property. By providing such a swing valve 52, it is possible to prevent the heat-supporting medium 30 from being supplied all at once, and it is possible to prevent the heat-supporting medium 30 from being stuck in the tube 300.

The pyrolyzer 20 located below the preheater 10 in the biomass gasifier is provided with an inlet for the heat carrier medium 30 above (upper), preferably at the top, and below (lower) the pyrolyzer 20. ), Preferably, the bottom is provided with a discharge port for the heat-bearing medium 30.

In the gasification device of the present embodiment, a preheater 10 for preheating the heat-carrying medium 30 is provided above the pyrolyzer 20, and the heat-carrying medium 30 is heated to a predetermined temperature. The preheater 10 is preferably provided on the upper part of the pyrolyzer 20, where all the heat-bearing media 30 are heated to a predetermined temperature, and the heat-bearing medium 30 heated to the temperature is brought into the pyrolyzer. Can be supplied to 20.

In the present embodiment, as shown in FIG. 1, a third valve 90 may be provided between the pyrolyzer 20 and the waste treatment device 240. Like the first valve 50, the third valve 90 may have a pair of damper valves 91a and 91b which are examples of the opening / closing part and a swing valve (third adjusting part) 92 which is an example of the adjusting part (FIG. 2). reference). In the third valve 90, the swing valve 92, the first damper valve 91a, and the second damper valve 91b may be arranged in order from the top. The waste treatment device 240 is provided with a filter F (see FIG. 1), and the soot contained in the biomass gas falls downward through the filter F, and the heat-carrying medium 30 that does not pass through the filter F is It is circulated by a circulation unit 290 composed of an elevator type, an escalator type, etc., and is charged into the preheater 10.

Steam may be sprayed by the steam atomizer 80 between the preheater 10 and the pyrolyzer 20 and / or between the pyrolyzer 20 and the waste treatment device 240 (see FIG. 5). When such an embodiment is adopted, the flow of gas can be blocked by water vapor, and it is possible to prevent the heating gas flowing through the preheater 10 and the gas from biomass from being mixed. When such an embodiment is adopted, only one damper valve may be used, and when the damper valve is in the open state, water vapor may be sprayed by the steam sprayer 80 to block the flow of gas. Such control may be performed by a command from the control device 100. Even when the steam sprayer 80 is provided, two or more damper valves may be provided.

A detector 110 for detecting the weight or the upper surface position of the heat-carrying medium 30 in the hopper 60 and the pyrolyzer 20 may be provided (see FIG. 4). Then, the control device 100 issues a command based on the data from the detector 110 or a command based on the calculation using the data from the detector 110 to the first valve 50 and the second valve 70, and the third valve 90. The operation of the first valve 50, the second valve 70, the third valve 90, and the steam sprayer 80 can be controlled by transmitting the data to the steam sprayer 80. The control device 100 includes a detection unit 101 that receives information from the detector 110, a calculation unit 102 that calculates information from the detection unit 101 and transmits information as a command to the control unit 103, valves 50, 70, 90, and water vapor. It may have a control unit 103 that transmits a command to the atomizer 80 (see FIGS. 5 and 8). A switch such as the first switch 120 or the second switch 130 may be driven by a command from the control device 100 to drive the valves 50, 70, 90 and the steam atomizer 80.

The second valve 70 can be composed of one or a plurality of swing valves 72 that swing continuously, but it is preferable that the second valve 70 is composed of one swing valve 72.

The second valve 70 can be composed of one or a plurality of rotary valves 74 (see FIGS. 2 and 9), but it is preferably composed of one rotary valve 74. The rotary valve 74 is divided into a plurality of spaces, and when the rotary valve 74 rotates, the heat-carrying medium 30 accommodated in each space is sequentially dropped (see FIG. 9).

The control device 100 may control the supply amount of the heat-carrying medium 30 to the pyrolyzer 20 by changing the swing cycle time and / or the swing distance of the swing valve 72. By changing the rotation speed of the rotary valve 74, the supply amount of the heat-carrying medium 30 to the pyrolyzer 20 may be controlled. By performing such control, the supply amount of the heat-supporting medium 30 can be appropriately adjusted.

Further, by providing the hopper 60 and providing the second valve 70 below the hopper 60, the hopper 60 absorbs the impact due to the drop of the heat-carrying medium 30 by receiving the heat-carrying medium 30 once. The heat-carrying medium 30 can be supplied to the pyrolyzer 20 while being adjusted by the second valve 70. Therefore, the heat-supporting medium 30 can be supplied in a more stable state.

[First aspect]
The first aspect of the control device 100 in the biomass gasification device of the present embodiment is that the first valve 50, the hopper 60, and the hopper 60 are located between the preheater 10 and the pyrolyzer 20 downward from the preheater 10. A second valve 70 is provided. Then, the control device 100 monitors the supply of the heat-carrying medium 30 from the preheater 10 through the pyrolyzer 20 and controls the operations of the first valve 50 and the second valve 70 based on the monitoring result. There is. As a result, stable continuous supply of the heat-bearing medium 30 in the gasifier is realized, pressure fluctuation of the pyrolyzer 20 is suppressed, problems such as deterioration of separation ability in gas separation are solved, and quality is stable. Gas can be provided.

In the first aspect, the control device 100 monitors the weight or top position (hereinafter, also referred to as “level”) of the heat-carrying medium 30 supplied from the preheater 10 through the first valve 50 in the hopper 60. If the weight or level falls below a predetermined value, the first switch 120 is operated to open the first valve 50. On the other hand, if the weight or the upper surface position exceeds a predetermined value, the second switch 130 is operated to close the first valve 50. The heat-supporting medium 30 is continuously supplied to the second valve 70, and the amount of the heat-supporting medium 30 supplied from the hopper 60 to the pyrolyzer 20 is controlled by the opening degree of the second valve 70.

[Second aspect]
In the second aspect, when the first valve 50 is opened, the valve is provided with a steam atomizer 80 that sprays a steam pulse and seals the valve with steam (see FIG. 5). The control device 100 can control the operation of the steam sprayer 80 to further improve the sealing property of the first valve 50 and prevent the backflow of gas.

When the third valve 90 is opened, the third valve 90 may be provided with a steam sprayer 80 that sprays a steam pulse and seals with steam. The control device 100 controls the steam sprayer 80 so as to spray the steam pulse on the third valve 90 when the third valve 90 is opened, and controls the discharge of the heat-bearing medium 30 from the pyrolyzer 20. Therefore, the sealing property of the third valve 90 can be further improved, and the backflow of gas can be prevented.

The first valve 50 is preferably composed of one or more swing valves 52 at the upper part and one or more damper valves 51 at the lower part, and the steam pulse spray from the steam sprayer 80 is preferably linked to the opening of the damper valve 51.

The third valve 90 is preferably composed of one or more swing valves 92 at the upper part and one or more damper valves 91 at the lower part, and the steam pulse spray from the steam sprayer 80 is preferably linked to the opening of the damper valve 91.

[Third aspect]
In the third aspect, the control device 100 supplies the heat-bearing medium 30 to the pyrolyzer 20 per unit time _{W kg / h in the hopper 60 as compared with a preset value W 0 kg / h.} When h is large, the opening degree of the second valve 70 is reduced to decrease it, and when the supply amount W kg / h is small, the opening degree of the second valve 70 is increased to increase it, and heat is carried to the pyrolyzer 20. The supply amount of the medium 30 may be controlled.

When the initial level is H and the final level is L, the time t and the weight from the initial level H to the final level L may be measured (see FIG. 10). When the cross-sectional area of the hopper 60 is S and the bulk density of the heat-supporting medium 30 is ρ, the calculation using the time t is calculated.
S × (HL) × ρ = reduced heat medium weight w (kg)
w / t = decrease rate (kg / h)
Will be.
_{The set value W 0} and the supply amount W may be calculated using the decrease rate (w / t), and the above control may be performed.

[Fourth aspect]
In the fourth aspect, the weight or the upper surface position of the heat-carrying medium 30 may be constantly monitored by the detector 110 in any one or more of the preheater 10, the hopper 60, and the pyrolyzer 20. (See FIGS. 4 and 6 to 8). Taking the heat-bearing medium 30 as an example, if the weight or the upper surface position falls below a certain value, a command to open / close the third valve 90 is transmitted to the third valve 90 at a speed faster than the normal speed X, and the weight or the upper surface position is changed. If it exceeds a certain value, a command to open / close the third valve 90 at a speed slower than the normal speed X is transmitted to the third valve 90, and when the weight or the upper surface position is a certain amount, the third valve 90 is opened / closed at the normal speed. It is also possible to control the operation of the 3 valve 90 to control the opening and closing of the 3rd valve 90.

[Other variants]
The aspect of the control device 100 in the biomass gasification device of the present embodiment may be incorporated into the conventional biomass gasification device.

The pyrolyzer 20 has a biomass supply port and a non-oxidizing gas supply port and / or a steam blow port.
The pyrolysis gas reformer 40 has a steam inlet and a reformed gas outlet.
A pyrolysis gas introduction pipe 200 provided between the pyrolysis device 20 and the pyrolysis gas reformer 40, which introduces the pyrolysis gas generated in the pyrolysis device 20 into the pyrolysis gas reformer 40. Including
Each of the thermal decomposition device 20 and the thermal decomposition gas reformer 40 further includes an inlet and an outlet for a preheated heat-bearing medium, and the heat of the heat-bearing medium causes thermal decomposition of biomass and thermal decomposition of biomass. Performed reformation of the pyrolysis gas generated by
The pyrolysis device 20 and the pyrolysis gas reformer 40 are provided in parallel with respect to the flow of the heat-bearing medium, and the pyrolysis gas introduction pipe 200 is provided with the pyrolysis device 20 and the pyrolysis gas reformer. On both sides of the vessel 40, on the side surfaces of the pyrolyzer 20 and the pyrolysis gas reformer 40 below the upper surface of the pyrolysis medium layer, which are formed in the pyrolyzer 20 and the pyrolysis gas reformer 40, respectively. The pyrolysis gas introduction pipe 200 is provided and is provided substantially horizontally with respect to the direction of gravity.
A first valve 50, a hopper 60, and a second valve 70 are provided between the preheater 10 and the pyrolyzer 20 downward from the preheater 10.
The control device 100 monitors the weight or the position of the upper surface of the heat-bearing medium 30 in the hopper 60, controls the operations of the first valve 50 and the second valve 70 based on the monitoring result, and from the preheater 10 to the pyrolyzer. It is possible to provide a biomass gasification device incorporating a control device 100 that controls the supply of the heat carrying medium 30 through the 20.

Further, the pyrolyzer 20 has a biomass supply port and a non-oxidizing gas supply port and / or a steam blow port.
The pyrolysis gas reformer 40 has a steam inlet and a reformed gas outlet.
A pyrolysis gas introduction pipe 200 provided between the pyrolysis device 20 and the pyrolysis gas reformer 40 is provided, and the pyrolysis gas generated in the pyrolysis device 20 is transferred to the pyrolysis gas reformer 40. Introduced,
The pyrolyzer 20 further includes an inlet and an outlet for a heat-supporting medium that has been preheated, and uses the heat of the heat-supporting medium to carry out thermal decomposition of biomass.
On the other hand, the pyrolysis gas reformer 40 executes steam reforming of the pyrolysis gas generated by the thermal decomposition of biomass.
The pyrolysis gas reformer 40 further includes an air or oxygen inlet, and performs steam reforming by partially burning the pyrolysis gas generated by the thermal decomposition of biomass with the air or oxygen.
The pyrolysis gas introduction pipe 200 is provided on the side surface of the pyrolyzer 20 below the upper surface of the heat-carrying medium layer formed in the pyrolyzer 20.
A first valve 50, a hopper 60, and a second valve 70 are provided between the preheater 10 and the pyrolyzer 20 downward from the preheater 10, and the control device 100 is a heat-bearing medium in the hopper 60. The weight or top position of 30 is monitored, the operation of the first valve 50 and the second valve 70 is controlled based on the monitoring result, and the supply of the heat-bearing medium 30 from the preheater 10 through the pyrolyzer 20 is controlled. It is possible to provide a biomass gasification device incorporating the control device 100.

In another embodiment of the present embodiment, the pyrolyzer 20 that heats the biomass in a non-oxidizing gas atmosphere or a mixed gas atmosphere of a non-oxidizing gas and steam, and the gas generated in the pyrolyzing device 20. Is provided with a pyrolysis gas reformer 40 that reforms the heat in the presence of steam, and the preheated heat-supporting medium 30 is charged into the pyrolyzer 20 to bring the heat-supporting medium 30 into the pyrolyzer 20. Pyrolysis of the biomass is carried out by the heat possessed, and then the pyrolysis gas generated by the pyrolysis of the biomass is introduced into the pyrolysis gas reformer 40 to carry out steam reforming of the pyrolysis gas. death,
A pyrolysis gas introduction tube provided on the side surface of the pyrolysis device 20 below the upper surface of the heat-supporting medium layer, in which the pyrolysis gas generated by the thermal decomposition of the biomass is formed in the pyrolysis device 20. Through 200, the pyrolysis gas reformer 40 is introduced into the pyrolysis gas reformer 40, and then the introduced pyrolysis gas is partially introduced into the pyrolysis gas reformer 40 by air or oxygen separately introduced into the pyrolysis gas reformer 40. In the method of gasifying biomass, which is pyrolyzed and reformed by steam introduced at the same time as the above air or oxygen.
A first valve 50, a hopper 60, and a second valve 70 are provided between the preheater 10 and the pyrolyzer 20 downward from the preheater 10, and heat is carried from the preheater 10 through the pyrolyzer 20. A method of gasifying biomass is provided that monitors and controls the supply of medium 30.

An example of the embodiment of the present embodiment will be described.

The heat-supporting medium 30, that is, the heat carrier, is preheated in the preheater 10 before being introduced into the pyrolyzer 20. The heat-supporting medium 30 is preferably heated to 650 to 800 ° C, more preferably 700 to 750 ° C. Below the above lower limit (650 ° C.), the biomass, for example, high ash biomass, cannot be sufficiently pyrolyzed in the pyrolyzer 20, and the amount of pyrolyzed gas generated decreases. On the other hand, if it exceeds the above upper limit (800 ° C.), it causes volatilization of phosphorus and potassium (potassium), and causes blockage and corrosion of pipes by diphosphorus pentoxide and potassium (potassium). In addition, it is not expected that the effect will be significantly increased only by giving extra heat, and on the contrary, it will only lead to high cost. It also causes a decrease in the thermal efficiency of the equipment.

The heat-supporting medium 30 heated to a predetermined temperature in the preheater 10 is then introduced into the pyrolyzer 20. In the pyrolyzer 20, the heat-carrying medium 30 is separately contacted with the biomass supplied to the pyrolyzer 20 from the biomass supply port 220. By the contact between the heat-supporting medium 30 and the biomass, the biomass is heated and thermally decomposed to generate a thermal decomposition gas. The generated pyrolysis gas passes through the pyrolysis gas introduction pipe 200 and is introduced into the pyrolysis gas reformer 40. At this time, tar, soot, etc. contained in the generated pyrolysis gas are captured by the heat-supporting medium 30 held in the pyrolysis gas introduction pipe 200, and a part or most of the tar is heated by the heat-supporting medium 30. The tar, soot, and the like remaining after being gasified are discharged from the bottom of the pyrolyzer 20 while still adhering to the heat-bearing medium 30.

The pyrolysis gas generated by thermally decomposing the biomass in the pyrolysis device 20 is introduced into the pyrolysis gas reformer 40 through the pyrolysis gas introduction pipe 200. The pyrolysis gas introduced into the pyrolysis gas reformer 40 is partially oxidized by air or oxygen, whereby the inside of the pyrolysis gas reformer 40 is heated. As a result, the pyrolysis gas reacts with steam, and the pyrolysis gas can be reformed into a hydrogen-rich gas.

Most of the heat required for the thermal decomposition of biomass in the thermal decomposition device 20 is supplied by the heat of the heat-bearing medium 30 that has been preheated to the above temperature. The introduction of the heat-bearing medium 30 into the pyrolyzer 20 and the discharge of the heat-bearing medium 30 from the pyrolyzer 20 are carried out, for example, by providing a total of two valves, one on the top and one on the bottom of the pipe, so-called two-stage. It is carried out using the type valve method (FIGS. 2 and 3).

By introducing the heat-bearing medium 30 into the pyrolyzer 20 and controlling the discharge rate of the heat-bearing medium 30 from the pyrolyzer 20, the heat-bearing medium layer is formed in the pyrolyzer 20 and the thickness of the layer is formed. The temperature can be controlled to an appropriate value, and the temperature of the pyrolyzer 20 can be controlled to the above-mentioned predetermined temperature. Here, if the discharge rate of the heat-bearing medium 30 from the pyrolyzer 20 is too fast, the temperature of the pyrolyzer 20 becomes high, while if the discharge rate is too slow, the heat-supporting medium 30 dissipates heat and heat. The temperature of the decomposer 20 becomes low.

As described above, by introducing the heat-bearing medium 30 from the preheater 10 to the pyrolyzer 20 and controlling the discharge rate of the heat-bearing medium 30 from the pyrolyzer 20, the heat in the stable pyrolyzer 20 is controlled. The generation of decomposition gas can be controlled. Therefore, control of the supply rate of the heat-bearing medium 30 from the first valve 50, the second valve 70, and the third valve 90 results in the stable generation of pyrolysis gas in the pyrolyzer 20. The control device 100 in the biomass gasification device of the present embodiment controls the supply rate of the heat-carrying medium 30 of the valve to bring about the stable generation of pyrolysis gas in the pyrolyzer 20.

As shown in FIG. 8, the control device 100 receives information from the detector 110 provided in any one or more of the preheater 10, the hopper 60, and the thermal decomposition device 20, and the detection unit 101 receives the received information. The calculation unit 102 processes and transmits the information after the calculation to the control unit 103, and finally, according to the command from the control unit 103, the first switch 120, the second switch 130, the first valve 50, and the second The valve 70, the third valve 90, the steam atomizer 80, and the like are controlled. As shown in FIG. 8, two or three or more control devices 100 may be provided, or only one control device 100 may be provided.

Hereinafter, the present embodiment will be described in more detail with reference to the examples, but the present embodiment is not limited to these examples.

The biomass raw material used in the examples and the gasifier used for the thermal decomposition and gas reforming of the biomass raw material are as follows.

As a biomass raw material, sewage sludge was granulated and used. The maximum size of the sewage sludge after granulation was about 6 to 15 mm. The properties of the sewage sludge are shown in Table 1. Table 2 shows the composition of the ash obtained by burning the sewage sludge.

For each value in Table 1, moisture, volatile matter and fixed carbon are measured according to JIS M8812, ash content is measured according to JIS Z 7302-4: 2009, and high calorific value is measured according to JIS M8814. It was done. In addition, among the elemental compositions, carbon (C), hydrogen (H) and nitrogen (N) all conform to JIS Z 7302-8: 2002, and sulfur (S) conforms to JIS Z 7302-7: 2002. Compliant and chlorine (Cl) was measured in accordance with JIS Z 7302-6: 1999. Further, oxygen (O) was obtained by subtracting each mass% of C, H, N, S, Cl and ash content from 100 mass%. Here, the ash content, the volatile content, the fixed carbon, and the elemental composition are all calculated on a drying basis. Moisture is the one at the time of receiving the biomass raw material (sewage sludge).

Regarding each value in Table 2, silicon dioxide, aluminum oxide, ferric oxide, magnesium oxide, calcium oxide, sodium oxide, potassium oxide, diphosphorus pentoxide and manganese oxide were measured in accordance with JIS M8815. .. Mercury, chromium, cadmium, copper oxide, lead oxide, zinc oxide and nickel were measured in accordance with JIS Z 7302-5: 2002.

The gasifier basically includes a pyrolyzer 20, a pyrolyzed gas reformer 40, and a preheater 10 (see FIG. 1), and includes the pyrolyzer 20 and the pyrolyzed gas reformer 40. Is connected by a pyrolysis gas introduction pipe 200 that introduces the pyrolysis gas generated in the pyrolysis device 20 into the pyrolysis gas reformer 40.

Here, one preheater 10 is provided above the thermal decomposition device 20, and the preheater 10 preheats the heat-bearing medium 30 supplied to the thermal decomposition device 20, and the heated heat. The carrying medium 30 is supplied to the thermal decomposer 20, supplies heat necessary for thermal decomposition of biomass, is extracted from the bottom thereof, and is returned to the preheater 10 again. On the other hand, the pyrolysis gas generated in the pyrolysis device 20 is introduced into the pyrolysis gas reformer 40 through the pyrolysis gas introduction pipe 200.

Here, air or oxygen is separately introduced into the pyrolysis gas reformer 40 from the air or oxygen introduction pipes 261,262, whereby the pyrolysis gas is partially burned, and at the same time, steam is generated. It is introduced from the steam inlet 242, the pyrolysis gas is reformed by steam, and the reformed gas obtained thereby is taken out from the reformed gas discharge port 230. Further, instead of the above-mentioned air or oxygen introduction pipe 261 and steam injection port 242, the air or oxygen and steam are provided in the heat decomposition gas introduction pipe 200, and the air or oxygen introduction pipe 262 and the steam injection port 243 are provided. It can be introduced from, or it can be introduced from all air or oxygen introduction pipes 261,262 and steam inlets 242 and 243.

The inner diameter of the straight body portion of the pyrolyzer 20 was about 550 mm, the height was about 1100 mm, and the internal volume was about 260 liters. The inner diameter of the straight body portion of the pyrolysis gas reformer 40 was about 600 mm, the height was about 1200 mm, and the internal volume was about 340 liters.

Further, the pyrolysis gas introduction pipe 200 is provided on the side of the pyrolyzer 20 on the side of the pyrolyzer 20 below the upper surface of the heat-bearing medium layer formed in the pyrolyzer 20. On the pyrolysis gas reformer 40 side, it is provided on the side surface near the bottom surface of the pyrolysis gas reformer 40. Further, the pyrolysis gas introduction pipe 200 is provided substantially horizontally with respect to the direction of gravity. As the pyrolysis gas introduction pipe 200, a pipe having a length of about 1000 mm and an inner diameter of about 80 mm is used, the inside thereof is covered with a heat insulating material, and the protruding portion is also formed of the heat insulating material. As the heat-carrying medium 30, a substantially spherical alumina ball having a diameter (maximum diameter) of 10 to 12 mm is used.

The heat-supporting medium 30 is pre-filled in the pyrolyzer 20 and the preheater 10 to a height of about 70% of each container, and then the heat-supporting medium 30 is charged in the preheater 10 at a temperature of about 700 ° C. Heat to. Next, the heat-supporting medium 30 is introduced from the top of the pyrolyzer 20 at an amount of 200 kilograms / hour, and an appropriate amount is extracted from the bottom of the pyrolyzer 20 to start circulation of the heat-supporting medium 30.

Due to the circulation of the heat-carrying medium 30, the gas phase temperature inside the pyrolyzer 20 and the temperature of the container itself gradually increased. While continuing such circulation of the heat-supporting medium 30, at the same time, the temperature of the heat-supporting medium 30 inside the preheater 10 is gradually raised to 800 ° C. After the heat-bearing medium 30 reaches the temperature, the circulation is further continued to gradually raise the gas phase temperature inside the pyrolyzer 20 from the time when the gas phase temperature of the pyrolyzer 20 exceeds 550 ° C. , The biomass raw material, nitrogen gas and steam are introduced into the pyrolyzer 20 from the biomass supply port 220, the non-oxidizing gas supply port 250 and the steam inlet 241 respectively, and the temperature of the pyrolyzer 20 becomes 600 ° C. To control.

At this time, the heat-supporting medium 30 is deposited in layers in the pyrolyzer 20, and the accumulated amount is about 60% by volume of the internal volume of the pyrolyzer 20. The amount of the heat-carrying medium 30 extracted from the pyrolyzer 20 was the same as the supply amount, and was 200 kg / hour in the pyrolyzer 20. The temperature of the heat-supporting medium 30 at the time of extraction is 650 ° C. However. The amount of the heat-carrying medium 30 extracted from the pyrolyzer 20 can be appropriately controlled according to the temperature condition.

In the above operation, the amount of sewage sludge as a biomass raw material is gradually increased from the biomass supply port 220 (see FIG. 2) to the pyrolyzer 20 using a quantitative feeder, and finally about 22 kg. Introduce continuously so that it becomes / hour (drying standard).

The temperature of the pyrolyzer 20 gradually decreases with the introduction of the biomass raw material, but at the same time, by introducing nitrogen gas and superheated steam into the pyrolyzer 20 while adjusting the supply amount thereof, the pyrolyzer 20 is introduced. The temperature of 20 is maintained at 600 ° C. Further, the pressure in the pyrolyzer 20 is maintained at 101.3 kPa.

Here, nitrogen gas is finally introduced at a fixed amount of 1000 liters / hour from the non-oxidizing gas supply port 250 provided in the upper part of the pyrolyzer 20. In addition, superheated steam (160 ° C., 0.6 MPa) is used as steam, and is finally introduced at a fixed amount of 1 kilogram / hour from the steam inlet 241 provided on the upper part of the pyrolyzer 20. NS. The residence time of the biomass raw material in the pyrolyzer 20 is about 1 hour. As a result, the gas generated by the thermal decomposition in the pyrolyzer 20 is obtained at 15 kilograms / hour. In addition, char and ash are discharged from the pyrolysis residue (char) outlet 210 at a total of 6.5 kg / hour.

The pyrolysis gas obtained in the pyrolysis device 20 subsequently passes through the pyrolysis gas introduction pipe 200 from the lower side surface of the pyrolysis device 20 and is introduced into the pyrolysis gas reformer 40.

At the beginning of the introduction of the pyrolysis gas, the temperature inside the pyrolysis gas reformer 40 becomes unstable, but the superheated steam introduced from the steam inlet 242 provided at the bottom of the pyrolysis gas reformer 40 By adjusting the amount and the amount of oxygen introduced from the air or oxygen introduction pipe 261, the pyrolysis gas is partially combusted and the temperature inside the pyrolysis gas reformer 40 is adjusted to 1000 ° C. do. At this time, the pyrolysis gas reformer 40 is held at a pressure of 101.3 kPa. The superheated steam from the steam inlet 242 provided at the bottom of the pyrolysis gas reformer 40 was finally introduced at a fixed amount of 3.7 kg / hour. Oxygen from the air or oxygen inlet 261 is finally introduced at a fixed amount of ^{2.3 m 3-normal / hour.} However, this amount of oxygen is appropriately increased or decreased depending on the degree of temperature rise inside the pyrolysis gas reformer 40.

By the above operation, the pyrolyzer 20 is held at a temperature of 600 ° C. and a pressure of 101.3 kPa, and the pyrolyzed gas reformer 40 is held at a temperature of 950 ° C. and a pressure of 101.3 kPa. As a result, the reformed gas having a temperature of 1000 ° C. is obtained from the reformed gas outlet 230 at an amount of 31 kg / hour.

The obtained reformed gas is collected in a rubber bag, and the gas composition is measured by gas chromatography. Table 3 shows the composition of the obtained reformed gas. In addition, the operation can be carried out continuously for 3 days. During the operation period, good continuous operation can be maintained without troubles, especially troubles caused by tar. Further, during the operation period, the heat-supporting medium 30 does not become blocked by tar or the like in the pyrolysis gas introduction pipe 200, and the pyrolysis gas from the pyrolysis device 20 to the pyrolysis gas reformer 40 does not occur. Smooth introduction is maintained. The amount of tar in the reformed gas taken out from the outlet of the pyrolysis gas reformer 40 is about 10 mg / m ^3- normal.

The reformed gas can be obtained in this way, and by realizing a stable continuous supply of the heat-carrying medium 30 in the gasifier, the pressure fluctuation of the pyrolyzer 20 is suppressed, and the separation ability in gas separation is lowered. It is possible to solve the problem and provide a gas with stable quality.

The biomass gasifier of the present embodiment includes a preheater 10, a pyrolyzer 20, and a pyrolyzed gas reformer 40, and further supplies a heat-bearing medium 30 from the preheater 10 to the pyrolyzer 20. By incorporating a control device that controls the discharge of the heat-bearing medium 30 from the pyrolyzer 20, stable continuous supply of the heat-bearing medium 30 in the gasifier is realized, and the pressure fluctuation of the pyrolyzer 20 is suppressed. It is possible to solve problems such as deterioration of separation ability in gas separation and provide gas with stable quality.

The biomass gasifier of the present embodiment can generate a reformed gas containing a large amount of valuable gas such as hydrogen from biomass, preferably biomass having a relatively high ash content, and is contained in the biomass. not only can prevent clogging and corrosion of the piping caused by the volatilization of diphosphorus pentoxide and potassium (potassium) contained in the ash, resulting suppressing the occurrence of N 2 _O, and the generation amount of tar and dust It is expected that it will be widely used as a gasifier for biomass, especially biomass with a relatively high ash content, because it can be reduced.

10 Preheater 20 Pyrolysis device 30 Heat carrier medium 40 Pyrolysis gas reformer 50 1st valve 51a 1st damper valve (1st opening / closing part)
51b 2nd damper valve (2nd opening / closing part)
52 Swing valve 60 Hopper 70 Second valve 72 Swing valve (adjustment part)
80 Steam sprayer 91a 1st damper valve 91b 2nd damper valve 91 Damper valve 92 Swing valve 100 Control device

Claims (9)

A preheater that preheats the heat-supporting medium and
A thermal decomposer that receives a supply of a heat-bearing medium preheated by the preheater and executes thermal decomposition of biomass by the heat of the heat-bearing medium.
A pyrolysis gas reformer that at least partially burns the pyrolysis gas generated by pyrolysis with air or oxygen.
A supply mechanism provided between the preheater and the pyrolyzer for supplying the heat-carrying medium from the preheater to the pyrolyzer, and
With
The supply mechanism
An opening / closing part for temporarily storing the heat-carrying medium and
An adjusting unit provided below the opening / closing unit and supplying the heat-carrying medium supplied from the opening / closing unit to the pyrolyzer by swinging or rotating.
Biomass gasifier with. The opening / closing portion has a first opening / closing portion and a second opening / closing portion provided below the first opening / closing portion.
A claim comprising a control device for opening the first opening / closing part while the second opening / closing part is closed and opening the second opening / closing part while the first opening / closing part is closed. The biomass gasification device according to 1. The biomass gasification device according to claim 2, wherein each of the first opening / closing part and the second opening / closing part is a damper valve. A hopper provided between the preheater and the pyrolyzer,
A control device that controls the supply of the heat-supporting medium from the preheater to the pyrolyzer based on the weight or top surface position of the heat-supporting medium in the hopper.
The biomass gasification device according to any one of claims 1 to 3, further comprising. The biomass gasification device according to any one of claims 1 to 4, wherein the adjusting unit is a swing valve or a rotary valve. The biomass gasification device according to any one of claims 1 to 5, further comprising a steam atomizer that sprays steam between the preheater and the pyrolyzer when the opening / closing portion is in the open state. The adjusting part is composed of a swinging part.
Any one of claims 1 to 6, further comprising a control device for controlling the supply amount of the heat-bearing medium to the pyrolyzer by changing the swing cycle time or swing distance of the swing portion. Biomass gasifier according to. The adjusting part is composed of a rotating part.
The biomass gas according to any one of claims 1 to 7, wherein the control device controls the supply amount of the heat-bearing medium to the pyrolyzer by changing the rotation speed of the rotating portion. Gasification device. A third valve provided below the pyrolyzer and
The biomass gasification device according to any one of claims 1 to 8, further comprising a steam sprayer that sprays steam when the third valve is in the open state.

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