WO2025126323A1 - Waste treatment device - Google Patents

Abstract

This waste treatment device comprises: a gasification/reforming furnace in which waste is thermally decomposed and gasified and a generated gas is reformed to produce a reformed gas; a cooling/cleaning water circulation device for cooling and cleaning the reformed gas produced in the gasification/reforming furnace; a gas purification device for purifying the reformed gas cooled and cleaned in the cooling/cleaning water circulation device; and a chemical-product production device for producing liquid chemical products from, as a raw material, the gas purified in the gas purification device. The cooling/cleaning water circulation device includes a heat collector for collecting some of the sensible heat of the reformed gas and is configured so that the sensible heat collected by the heat collector is supplied to the chemical-product production device.

Description

Waste treatment equipment

The present invention relates to a waste treatment device.

In the gasification and reforming furnace described in Patent Document 1, which decomposes harmful substances such as waste in a high-temperature oxidizing atmosphere, oxygen-containing gas, which is a combustion-supporting gas, is blown into the lower part of the high-temperature reactor to gasify and melt the waste. In addition, in the upper part of the furnace, in order to maintain the temperature of the generated gas, oxygen-containing gas is blown in to combust a portion of the gas, reforming the gas at a high temperature of about 1200°C, synthesizing it into a reformed gas whose main components are carbon monoxide (CO), carbon dioxide ( _CO2 ), and hydrogen ( _H2 ), which is then cooled and refined for use as fuel gas, etc.

JP 2010-223526 A

　Conventionally, the reformed gas discharged from the gasification reforming furnace is rapidly cooled with a large amount of cooling water to prevent the resynthesis of dioxins. As a result, the sensible heat of the reformed gas, which reaches over 1100°C at the outlet of the gasification reforming furnace, is discarded without being recovered or reused, leaving room for improvement from the perspective of effective energy utilization.

The present invention was made in consideration of the above problems, and its purpose is to provide a waste treatment device that can recover and reuse a portion of the sensible heat of the reformed gas produced in the gas reforming furnace.

In order to solve the above problems and achieve the objectives,
(1) A waste treatment device according to the present invention is a waste treatment device comprising a gasification and reforming furnace that thermally decomposes and gasifies waste and reforms the generated gas to produce a reformed gas, a cooling and cleaning water circulating device that cools and cleans the reformed gas produced in the gasification and reforming furnace, a gas refining device that purifies the reformed gas cooled and cleaned by the cooling and cleaning water circulating device, and a chemical product manufacturing device that produces liquid chemical products using the purified gas refined by the gas refining device as a raw material, wherein the cooling and cleaning water circulating device has a heat recovery device that recovers a portion of the sensible heat of the reformed gas, and is configured to supply the sensible heat recovered by the heat recovery device to the chemical product manufacturing device.

(2) The waste treatment device according to the present invention is the above-mentioned (1) invention, in which the cooling and cleaning water circulation device is equipped with a quenching and cleaning device that quenches and cleans the reformed gas from which a portion of the sensible heat has been recovered by the heat recovery device with quenching and cleaning water, and the heat recovery device is characterized in that it recovers sensible heat from the reformed gas to a temperature not lower than 300°C from the temperature of the reformed gas at the outlet side of the gasification and reforming furnace.

(3) The waste treatment device according to the present invention is the invention of (2) above, characterized in that the heat recovery device is a boiler having a structure composed of a plurality of water tubes arranged in a cylindrical shape, a plurality of connecting fins connecting adjacent water tubes in the circumferential direction, an annular upper header connected to the upper ends of the plurality of water tubes and the plurality of connecting fins, and an annular lower header connected to the lower ends of the plurality of water tubes and the plurality of connecting fins.

(4) The waste treatment device according to the present invention is the invention (3) above, characterized in that an upper flange is provided on the upper part of the boiler for connecting to a gas duct through which the reformed gas sent from the gasification reforming furnace passes, and an upper compensator is provided between the upper flange and the upper header, capable of absorbing the thermal expansion difference between the upper flange and the upper header.

(5) The waste treatment device according to the present invention is the invention of (4) above, characterized in that a gas supply port for supplying the reformed gas from the gas duct into the boiler is provided in the radial center of the upper flange, a water channel for flowing cooling water is provided inside the upper flange near the gas supply port, the part of the upper flange exposed to the reformed gas sent from the gas supply port into the boiler is made of a material having heat resistance and corrosion resistance, and the part of the upper flange that is inside the exposed part and comes into contact with the cooling water flowing through the water channel is made of a material having high thermal conductivity.

(6) The waste treatment device according to the present invention is the above-mentioned (3) in which the boiler is provided with a solid matter removal device that removes solid matter adhering to the inner circumferential surface of the structure.

(7) The waste treatment device according to the present invention is the above-mentioned (6) and is characterized in that the solid matter removal device is provided with a water injection device that injects water toward the inner surface of the structure.

(8) The waste treatment device according to the present invention is characterized in that, in the invention (6) above, the solid matter removal device is provided with a hammer device that strikes the outer peripheral surface of the structure.

(9) The waste treatment device according to the present invention is any one of the above (3) to (8) and is characterized in that the water pipe is made of low alloy steel.

(10) The waste treatment device according to the present invention is any one of the above (3) to (8) and is characterized in that a thermal spray coating made of a material having heat resistance and corrosion resistance is formed on the outer circumferential surface of the water pipe.

(11) The waste treatment device according to the present invention is any one of the above (3) to (8) and is characterized in that the surface of the water pipe that comes into contact with the reformed gas is a polished surface.

(12) The waste treatment device according to the present invention is any one of the inventions (4) to (11) above, characterized in that the boiler includes an upper flange side suspension fin provided on the underside of the upper flange, an upper water tube side suspension fin provided on the outer peripheral surface of the upper part of the water tube, and a fastening member fastening the upper flange side suspension fin and the upper water tube side suspension fin, and the water tube is suspended from the upper flange.

(13) The waste treatment device according to the present invention is any one of the inventions (3) to (12) above, characterized in that a flow guide plate is provided at the bottom of the boiler to guide the molten slag that has flowed down the inner surface of the structure toward the center in the radial direction of the structure and collect it.

The waste treatment device according to the present invention has the effect of recovering and reusing a portion of the sensible heat of the reformed gas discharged from the gas reformer.

FIG. 1 is a block diagram showing a schematic configuration of a waste treatment device according to an embodiment. FIG. 2 is a perspective view showing a schematic configuration of a boiler according to the embodiment. FIG. 3 is a partially enlarged view of an upper portion of the boiler according to the embodiment. FIG. 4 is a cross-sectional view of a lower part of a boiler according to an embodiment. FIG. 5 is a partial cross-sectional view of the upper part of a boiler when a water injection device is provided as a solid matter removal device. FIG. 6 is a partial cross-sectional view of the upper part of a boiler when a hammer device is provided as a solid matter removal device.

Below, an embodiment of the waste treatment device according to the present invention will be described. Note that the present invention is not limited to this embodiment.

FIG. 1 is a block diagram showing the general configuration of a waste treatment device 1 according to an embodiment.

As shown in FIG. 1, the waste treatment device 1 according to the embodiment includes a waste input device 10, a gasification reformer 50, a cooling and cleaning water circulation device 70, a gas purification device 80, a cleaning water treatment device 90, and a chemical product manufacturing device 100.

The waste input device 10 inputs waste into the gasification and reforming furnace 50. The gasification and reforming furnace 50 thermally decomposes and gasifies the waste, and reforms the gas generated to produce reformed gas. The gasification and reforming furnace 50 is a vertical furnace, and approximately its lower half is formed as a thermal decomposition section 52 and a melting section 54 located below the thermal decomposition section 52, and approximately its upper half is formed as a gas reforming section 53.

In the pyrolysis section 52, waste is accumulated to form a waste accumulation layer Q. The waste forming the waste accumulation layer Q is gasified by pyrolysis and non-combustibles are melted. A plurality of gas supply members 20 for supplying oxygen (O ₂ ) into the waste accumulation layer Q are provided at the lower part of the side wall of the gasification and reforming furnace 50. The gas supply members 20 also function as gas burners for burning liquefied natural gas (LNG) to keep the pyrolysis section 52 at a high temperature. Note that FIG. 1 illustrates one of the plurality of gas supply members 20 provided at the lower part of the side wall of the gasification and reforming furnace 50. When the waste is pyrolyzed in the pyrolysis section 52, hydrogen (H ₂ ), carbon monoxide (CO), and the like are generated.

In the gas reforming section 53, in order to maintain the temperature of the gas generated from the waste pile Q in the thermal decomposition section 52, an oxygen-containing gas is blown in to burn a part of the gas, and the gas is reformed at a high temperature of about 1200°C to generate a reformed gas mainly composed of carbon monoxide (CO), carbon dioxide (CO ₂ ), and hydrogen (H ₂ ). That is, oxygen (O ₂ ) supplied from the gas supply member 20 into the furnace reacts with carbon (C) in the waste to generate carbon monoxide (CO) and carbon dioxide (CO ₂ ). In addition, since there is high-temperature steam generated from the waste or supplied as water from the outside, a reaction occurs between carbon (C) and steam (H ₂ O) to generate hydrogen (H ₂ ) and carbon monoxide (CO). Furthermore, hydrocarbons generated by the thermal decomposition and partial oxidation of the waste react with steam (H ₂ O) to generate hydrogen (H ₂ ) and carbon monoxide (CO). The process of generating gas rich in hydrogen (H ₂ ) and carbon monoxide (CO) from the gas generated from these waste materials is called reforming. A plurality of gas supply members 20 that supply oxygen (O ₂ ) into the gas reforming section 53 are provided on the upper part of the side wall of the gasification reforming furnace 50. The gas supply members 20 also function as gas burners that burn liquefied natural gas (LNG) to keep the gas reforming section 53 at a high temperature. Note that FIG. 1 illustrates one of the plurality of gas supply members 20 provided on the upper part of the side wall of the gasification reforming furnace 50.

In the melting section 54, the molten material produced in the pyrolysis section 52 is further heated, and carbon and other substances contained in the molten material are gasified and removed. In the melting section 54, a molten material outlet 58 for discharging the molten material to the outside is provided at the bottom of the gasification and reforming furnace 50.

A gas duct 60 is provided at the top of the gasification reforming furnace 50, extending from a reformed gas outlet 59 formed at the top, for discharging the reformed gas generated in the gas reforming section 53 outside the furnace. A cooling and cleaning water circulating device 70 is provided downstream of the gas duct 60 for cooling and cleaning the reformed gas. The cooling and cleaning water circulating device 70 has a boiler 71 as a first heat exchanger that is a heat recovery device, a cooling and cleaning device 72, a settling tank 73, and a second heat exchanger 74.

The boiler 71 is connected to the gas duct 60 and recovers a portion of the sensible heat from the reformed gas. The method of recovering the sensible heat of the reformed gas by the boiler 71 is to generate steam by heating the water flowing through the multiple water pipes 7107 provided in the boiler 71 with the sensible heat of the reformed gas. The steam generated by the boiler 71 is supplied to the chemical product manufacturing equipment 100 through the piping 75, etc. In addition, the condensate after using the steam in the chemical product manufacturing equipment 100 is returned to the boiler 71 again through the piping 76, etc. In addition, the method of recovering the sensible heat of the reformed gas by the first heat exchanger is not limited to using the boiler 71, and heat transfer to hot water/brine may be adopted. In addition, the piping system for the steam/condensate may be equipped with a steam drum, a deaerator, a condensate tank, a chemical injection device, a safety valve, etc.

A cooling and cleaning device 72 is disposed downstream of the boiler 71. The cooling and cleaning device 72 is connected to the boiler 71, and uses cooling and cleaning water to rapidly cool the reformed gas from which part of the sensible heat has been recovered by the boiler 71, and removes water-soluble components, dust, carbon particles, and the like from the reformed gas. The settling tank 73 stores the cooling and cleaning water used to cool and clean the reformed gas in the cooling and cleaning device 72, and separates the solids contained in the cooling and cleaning water by settling. The second heat exchanger 74 cools the cooling and cleaning water from which the solids have been separated. The cooling and cleaning water cooled in the second heat exchanger 74 is returned to the cooling and cleaning device 72.

In the waste treatment device 1 according to the embodiment, a portion of the sensible heat of the reformed gas, which is a high-temperature synthesis gas synthesized in the gasification reforming furnace 50 from waste as a chemical raw material, is recovered by the boiler 71. In this case, in the waste treatment device 1 according to the embodiment, the boiler 71 recovers sensible heat from the reformed gas at the outlet side of the gasification reforming furnace 50 from a temperature of 1100°C or more to a temperature not lower than 300°C. As a result, the cooling and cleaning device 72 provided downstream of the boiler 71 rapidly cools the reformed gas from a temperature sufficiently higher than the resynthesis temperature of dioxins, making it possible to avoid resynthesis of dioxins. In other words, in the waste treatment device 1 according to the embodiment, it is possible to recover the sensible heat of the reformed gas that was previously discarded, while also avoiding the resynthesis of dioxins, which is essential for handling reformed gas derived from waste. In addition, since the sensible heat of the reformed gas is recovered in the boiler 71 to lower the temperature of the reformed gas, the cooling load of the reformed gas in the cooling and cleaning device 72 is reduced, so the amount of water and electricity used in the cooling and cleaning device 72 can be significantly reduced.

A gas purification device 80 is provided downstream of the cooling and cleaning device 72, which purifies the reformed gas cooled and cleaned by the cooling and cleaning device 72 to produce purified gas that can be used as fuel gas.

The chemical product manufacturing apparatus 100 receives the purified gas from the gas purification apparatus 80, and synthesizes and produces ethanol as a liquid chemical product by, for example, a catalytic reaction using hydrogen (H ₂ ) and carbon monoxide (CO) in the purified gas as raw materials. The chemical product manufacturing apparatus 100 also uses steam supplied from the boiler 71 through a pipe 75 or the like in, for example, a distillation process for producing ethanol. In addition to ethanol, the chemical product manufacturing apparatus 100 may also produce liquid chemical products such as dimethyl ether and methanol using hydrogen (H ₂ ) and carbon monoxide (CO) in the purified gas as raw materials.

FIG. 2 is a perspective view showing the schematic configuration of a boiler 71 according to an embodiment. FIG. 3 is a partially enlarged view of the upper part of the boiler 71 according to an embodiment. FIG. 4 is a cross-sectional view of the lower part of the boiler 71 according to an embodiment.

2, the boiler 71 according to the embodiment includes an upper flange 7101, an upper header 7102, steam exhaust pipes 7103A, 7103B, a lower flange 7104, a lower header 7105, water supply pipes 7106A, 7106B, a plurality of water pipes 7107, and a plurality of connecting fins 7108. Furthermore, the boiler 71 according to the embodiment includes upper flange side suspension fins 7109A, 7109B, upper water pipe side suspension fins 7110A, 7110B, lower flange side suspension fins 7112A, 7112B, lower water pipe side suspension fins 7113A, 7113B, and bolts 7111A, 7111B, 7114A, 7114B.

The upper flange 7101 is fastened to the flange of the gas duct 60 by bolts 7141 and nuts 7142 (see FIG. 3) or the like. A gas supply port 7101a is provided in the radial center of the upper flange 7101 for supplying the reformed gas sent from the gasification reformer 50 through the gas duct 60 into the boiler 71. The lower flange 7104 is fastened to the flange of the cooling and cleaning device 72 by bolts and nuts or the like. A gas exhaust port 7104a is provided in the radial center of the lower flange 7104 for exhausting the reformed gas from inside the boiler to the cooling and cleaning device 72.

The water pipes 7107 are arranged in a cylindrical shape, and adjacent water pipes 7107 in the circumferential direction are connected to each other by a plurality of connecting fins 7108. The upper header 7102 is annular and is connected to the upper ends of the water pipes 7107 and the connecting fins 7108. One end of a pair of steam exhaust pipes 7103A, 7103B is connected to the outer circumferential surface of the upper header 7102. The other end of the steam exhaust pipes 7103A, 7103B is connected to a pipe 75 for sending steam to the chemical product manufacturing apparatus 100. As a result, the steam generated by heating the water flowing through each of the water pipes 7107 with the sensible heat of the reformed gas is discharged from the steam exhaust pipes 7103A, 7103B to the pipe 75 via the upper header 7102.

The lower header 7105 is annular and is connected to the lower ends of the multiple water pipes 7107 and the multiple connecting fins 7108. One end of a pair of water supply pipes 7106A, 7106B is connected to the outer circumferential surface of the lower header 7105. The other ends of the water supply pipes 7106A, 7106B are connected to a pipe 76 for sending condensate from the chemical manufacturing equipment 100 to the boiler 71. As a result, the condensate generated by using the sensible heat of steam in the chemical manufacturing equipment 100 is supplied from the pipe 76 through the water supply pipes 7106A, 7106B to the lower header 7105, and is used again for heat recovery (heat exchange) in the multiple water pipes 7107.

In the boiler 71 according to the embodiment, the structure composed of the water pipes 7107, the connection fins 7108, the upper header 7102, the lower header 7105, the steam exhaust pipes 7103A, 7103B, and the water supply pipes 7106A, 7106B is also referred to as the boiler body. The inner surface of the side wall formed by the water pipes 7107 and the connection fins 7108 in the circumferential direction of the boiler body forms a heat transfer surface for transferring heat from the reformed gas passing through the internal space 710 of the boiler body to the water (steam) passing through the water pipes 7107 to perform heat exchange (heat recovery). In the boiler 71 according to the embodiment, the side wall is formed by the water pipes 7107 and the connection fins 7108 in the circumferential direction of the boiler body, so that the reformed gas can be prevented from leaking to the outside from between the adjacent water pipes 7107 even when the internal space 710 of the boiler body is in a positive pressure state.

Also, in the upper part of the boiler 71, upper flange side suspension fins 7109A, 7109B are provided on the radially outer side of the lower surface of the upper flange 7101. Also, in the boiler 71 according to the embodiment, upper water tube side suspension fins 7110A, 7110B are provided on the outer peripheral surface of the upper part of any water tube 7107 among the multiple water tubes 7107, corresponding to the upper flange side suspension fins 7109A, 7109B. The upper flange side suspension fins 7109A, 7109B and the upper water tube side suspension fins 7110A, 7110B are fastened by bolts 7111A, 7111B and nuts, which are fastening members. In this way, in the boiler 71, the upper flange side suspension fins 7109A and the upper water tube side suspension fins 7110A are fastened to each other, thereby suspending the water tubes 7107 (boiler body) from the upper flange 7101. In FIG. 2, two sets of upper flange side suspension fins 7109A, 7109B and upper water pipe side suspension fins 7110A, 7110B are provided, but this is not limited to this.

3, for example, the bolt hole 7115A provided in the upper flange side suspension fin 7109A and the bolt hole (not shown) provided in the upper water tube side suspension fin 7110A are elongated holes that are long in the radial direction of the upper flange 7101 (boiler body) in order to insert the bolt 7111A. Although not shown, the upper flange side suspension fin 7109B and the upper water tube side suspension fin 7110B also have bolt holes formed as elongated holes that are long in the radial direction of the upper flange 7101 (boiler body) in order to insert the bolt 7111B. This allows the radial thermal expansion during operation of the boiler 71 to be absorbed by each bolt hole formed as an elongated hole, and the water tube 7107 (boiler body) can be suspended from the upper flange 7101 while avoiding structural destruction caused by thermal expansion.

Furthermore, lower flange side suspension fins 7112A, 7112B are provided radially outward on the upper surface of lower flange 7104 at the lower part of boiler 71. Furthermore, lower water tube side suspension fins 7113A, 7113B are provided corresponding to lower flange side suspension fins 7112A, 7112B on the outer peripheral surface of the lower part of any water tube 7107 among the multiple water tubes 7107 in boiler 71. The lower flange side suspension fins 7112A, 7112B and the lower water tube side suspension fins 7113A, 7113B are fastened to each other by fastening members, bolts 7114A, 7114B and nuts. In this way, the boiler 71 is structured so that the lower flange 7104 is suspended from the water tube 7107 (boiler body) by fastening the lower flange side suspension fins 7112A, 7112B and the lower water tube side suspension fins 7113A, 7113B. Note that in FIG. 2, the lower flange side suspension fins 7112A, 7112B and the lower water tube side suspension fins 7113A, 7113B are provided in two sets, but this is not limiting.

Although not shown, the lower flange side suspension fins 7112A, 7112B and the lower water tube side suspension fins 7113A, 7113B each have a bolt hole formed as a long hole extending in the radial direction of the lower flange 7104 (boiler body) for inserting the bolts 7114A, 7114B. This allows the radial thermal expansion during operation of the boiler 71 to be absorbed by each bolt hole formed as a long hole, and the lower flange 7104 can be suspended from the water tube 7107 (boiler body) while avoiding structural destruction caused by thermal expansion.

Also, at the top of the boiler 71, as shown in FIG. 3, the upper header 7102 is airtightly connected to the upper flange 7101 by the upper compensator 7130. This makes it possible for the upper compensator 7130 to prevent the reformed gas from leaking to the outside between the upper header 7102 and the upper flange 7101, even when the internal space 710 of the boiler 71 is in a positive pressure state.

In addition, at the top of the boiler 71, the water tube 7107 is suspended from the upper flange 7101 by fastening the upper flange side suspension fins 7109A, 7109B to the upper water tube side suspension fins 7110A, 7110B independently of the upper compensator 7130. This makes it possible to suppress the action of stresses other than thermal stresses (such as stresses due to the load of the boiler body) on the upper compensator 7130, thereby realizing a structure in which the upper compensator 7130 is less likely to break.

Furthermore, at the bottom of the boiler 71, as shown in FIG. 4, the lower flange 7104 is airtightly connected to the lower header 7105 by the lower compensator 7180. This makes it possible for the lower compensator 7180 to prevent the reformed gas from leaking to the outside between the lower header 7105 and the lower flange 7104 even when the internal space 710 of the boiler 71 is in a positive pressure state.

In addition, at the bottom of the boiler 71, the lower flange 7104 is suspended from the water tube 7107 (boiler body) by fastening the lower flange side suspension fins 7112A, 7112B to the lower water tube side suspension fins 7113A, 7113B independently of the lower compensator 7180. This makes it possible to suppress the action of stresses other than thermal stresses (such as stresses due to the load of the boiler body) on the lower compensator 7180, realizing a structure in which the lower compensator 7180 is less likely to break.

The boiler 71 according to the embodiment must have an airtight structure so that the reformed gas supplied from the gasification reformer 50 through the gas duct 60 to the internal space 710 of the boiler 71 does not leak to the outside. On the other hand, the upper flange 7101 and the upper header 7102, and the lower flange 7104 and the lower header 7105 have significantly different temperatures during operation of the boiler 71, so if they are joined by welding or the like as they are, there is a concern that the welds may be damaged due to the difference in thermal expansion in the radial direction. In contrast, in the boiler 71 according to the embodiment, the upper compensator 7130 provided between the upper flange 7101 and the upper header 7102, and the lower compensator 7180 provided between the lower flange 7104 and the lower header 7105 can absorb the difference in thermal expansion during operation of the boiler 71. Therefore, in the boiler 71 according to the embodiment, it is possible to ensure airtightness while avoiding structural destruction caused by the difference in thermal expansion during operation.

Also, as shown in FIG. 3, in the upper part of the boiler 71 according to the embodiment, a plurality of water channels 7120 for flowing cooling water are provided inside the upper flange 7101 near the gas supply port 7101a in the radial direction of the upper flange 7101. In the upper flange 7101, the exposed part 7121 to the reformed gas sent from the gas supply port 7101a to the internal space 710 of the boiler body is made of a material having heat resistance and corrosion resistance such as Hastelloy. In addition, the part of the upper flange 7101 that is on the inner side of the exposed part 7121 and comes into contact with the cooling water flowing through the water channel 7120 is made of a copper member 7122 as a material having high thermal conductivity. As a result, the upper flange 7101 can suppress corrosion due to trace components derived from waste in the reformed gas and damage due to heat damage over a long period of time.

Also, as shown in FIG. 4, a plurality of water channels 7170 for flowing cooling water are provided inside the lower flange 7104 near the gas exhaust port 7104a in the radial direction of the lower flange 7104. In the lower flange 7104, the part exposed to the reformed gas discharged from the internal space 710 of the boiler body to the outside through the gas exhaust port 7104a is made of a heat-resistant and corrosion-resistant material such as Hastelloy. In addition, the exposed part of the lower flange 7104 is also on the internal side, and the part in contact with the cooling water flowing through the water channel 7170 is made of a copper member as a material with high thermal conductivity. As a result, the lower flange 7104 can suppress corrosion due to trace components derived from waste in the reformed gas and damage due to heat damage over a long period of time.

Furthermore, in the boiler 71 according to the embodiment, the water tubes 7107 may be made of low alloy steel. This makes it easier for molten slag that has flown into the internal space 710 of the boiler body together with the reformed gas and adhered to the water tubes 7107 to peel off due to its own weight, making it possible to maintain a stable heat transfer capacity in the water tubes 7107 for a long period of time.

Furthermore, in the boiler 71 according to the embodiment, a material having heat resistance and corrosion resistance, such as Hastelloy, may be sprayed onto the outer peripheral surface of the water tube 7107 to form a sprayed coating on the outer peripheral surface of the water tube 7107. This makes it easier for the molten slag adhering to the sprayed coating of the water tube 7107 to peel off due to its own weight, and makes it possible to maintain a stable heat transfer capacity of the water tube 7107 for a long period of time.

Furthermore, in the boiler 71 according to the embodiment, the surface of the water tube 7107 that comes into contact with the reformed gas may be polished to a polished surface. This makes it easier for the molten slag adhering to the polished surface of the water tube 7107 to peel off due to its own weight, and makes it possible to maintain a stable heat transfer capacity of the water tube 7107 for a long period of time.

Then, as shown in FIG. 4, a flow guide plate 7190 is provided at the bottom of the boiler 71 according to the embodiment, which guides and collects the molten slag that has detached from the water tubes 7107 and flowed down the inner circumferential surface of the boiler body toward the center in the radial direction of the boiler body. The flow guide plate 7190 is arranged at an incline with respect to the radial direction of the boiler body so that the edge of the gas exhaust port 7104a at the upper end of the lower flange 7104 and the lower end are in contact with each other, and the upper end is in contact with the inner circumferential surface of the boiler body. As a result, the molten slag that has flowed down the inner circumferential surface of the boiler body is guided by the flow guide plate 7190 to the gas exhaust port 7104a of the lower flange 7104, and can be dropped into the cooling and cleaning device 72 without accumulating at the bottom of the boiler 71. This enables the boiler 71 to operate stably for a long period of time.

In addition, the boiler 71 according to the embodiment may be provided with a solids removal device that removes solids such as molten slag adhering to the multiple water tubes 7107.

Figure 5 is a partial cross-sectional view of the upper part of the boiler 71 when a water injection device 7150 is installed as a solid matter removal device.

In the boiler 71 according to the embodiment, as shown in FIG. 5, the solid matter removal device may include a water injection device 7150 that injects water supplied from the internal space 710 of the boiler body through a water supply pipe 7151 from a nozzle 7150a toward the inner circumferential surface of the boiler body. The water injection device 7150 is provided, for example, at the tip of the water supply pipe 7151 inserted into the internal space 710 of the boiler body from the gas supply port 7101a of the upper flange 7101. The water injection device 7150 can change the position and orientation of the nozzle 7150a of the water injection device 7150 relative to the inner circumferential surface of the boiler body by moving the water supply pipe 7151 up and down or rotating it in the internal space 710 of the boiler body.

The water injection device 7150, for example, injects water from a nozzle 7150a toward the molten slag, which is a solid material adhering to the water tube 7107. The injected water then collides with the high-temperature molten slag and evaporates, and the energy and heat shock generated by the evaporation causes the molten slag to peel off and be removed from the water tube 7107. As a result, the boiler 71 according to the embodiment can maintain a stable heat transfer capacity in the water tube 7107 for a long period of time.

Figure 6 is a partial cross-sectional view of the upper part of the boiler 71 when a hammer device 7160 is installed as a solid removal device.

Furthermore, in the boiler 71 according to the embodiment, as shown in FIG. 6, the solid matter removal device may be a hammering device 7160 operated by compressed air from outside the boiler 71. The hammering device 7160 periodically strikes the outer circumferential surface of the boiler body with compressed air supplied from a compressed air supply pipe 7161, impacting the molten slag, which is a solid matter adhering to the water tube 7107, and removing the molten slag from the water tube 7107. As a result, in the boiler 71 according to the embodiment, it is possible to maintain a stable heat transfer capacity in the water tube 7107 for a long period of time.

The present invention provides a waste treatment device that can recover and reuse a portion of the sensible heat of the reformed gas discharged from the gas reformer.

1 Waste treatment device 10 Waste input device 20 Gas supply member 50 Gasification reforming furnace 52 Pyrolysis section 53 Gas reforming section 54 Melting section 58 Melt discharge port 59 Reformed gas discharge port 60 Gas duct 70 Cooling and cleaning water circulation device 71 Boiler 72 Cooling and cleaning device 73 Settling tank 74 Second heat exchanger 80 Gas purification device 90 Cleaning water treatment device 100 Chemical product manufacturing device 710 Internal space 7101 Upper flange 7101a Gas supply port 7102 Upper header 7103A, 7103B Steam discharge pipe 7104 Lower flange 7104a Gas discharge port 7105 Lower header 7106A, 7106B Water supply pipe 7107 Water pipe 7108 Connection fins 7109A, 7109B Upper flange side suspension fins 7110A, 7110B Upper water pipe side suspension fin 7111A Bolt 7115A Bolt hole 7120 Water passage 7121 Exposed portion 7122 Copper member 7130 Upper compensator 7141 Bolt 7142 Nut 7150 Water injection device 7150a Nozzle 7151 Water supply pipe 7160 Striking device 7161 Compressed air supply pipe 7170 Water passage 7180 Lower compensator 7190 Flow guide plate

Claims (13)

a gasification and reforming furnace that generates reformed gas by pyrolyzing and gasifying the waste;
a cooling and cleaning water circulating device for cooling and cleaning the reformed gas generated in the gasification and reforming furnace;
a gas purification device that purifies the reformed gas that has been cooled and washed by the cooling and washing water circulating device;
a chemical product manufacturing apparatus for manufacturing a liquid chemical product using the purified gas obtained by the gas purification apparatus as a raw material;
A waste treatment device comprising:
the cooling and cleaning water circulating device has a heat recovery device that recovers a portion of the sensible heat of the reformed gas,
13. A waste treatment apparatus comprising: a heat recovery device that recovers sensible heat and supplies the recovered sensible heat to the chemical product manufacturing apparatus. the cooling and cleaning water circulating device includes a quenching and cleaning device that quenches and cleans the reformed gas from which a portion of the sensible heat has been recovered by the heat recovery device, with quenching and cleaning water;
2. The waste treatment apparatus according to claim 1, wherein the heat recovery device recovers sensible heat from the reformed gas until the temperature of the reformed gas at the outlet of the gasification reforming furnace is not lower than 300°C. The heat recovery device includes:
A plurality of water tubes arranged in a cylindrical shape;
a plurality of connecting fins connecting adjacent water tubes in the circumferential direction;
an annular upper header connected to upper ends of the water pipes and the connecting fins;
an annular lower header connected to lower ends of the plurality of water pipes and the plurality of connecting fins;
3. The waste treatment device according to claim 2, wherein the waste treatment device is a boiler having a structure constituted by: The upper part of the boiler is provided with:
An upper flange is provided for connection to a gas duct through which the reformed gas sent from the gasification and reforming furnace passes,
4. The waste treatment device according to claim 3, further comprising an upper compensator provided between said upper flange and said upper header, said upper compensator being capable of absorbing a thermal expansion difference between said upper flange and said upper header. a gas supply port for supplying the reformed gas from the gas duct into the boiler is provided at a radial center of the upper flange,
a water passage for flowing cooling water is provided inside the upper flange near the gas supply port,
In the upper flange,
a portion exposed to the reformed gas sent from the gas supply port into the boiler is made of a material having heat resistance and corrosion resistance,
The waste treatment device as described in claim 4, characterized in that the portion of the upper flange that is inside the exposed portion and in contact with the cooling water flowing through the water channel is made of a material having high thermal conductivity. The waste treatment device according to claim 3, characterized in that the boiler is equipped with a solid matter removal device that removes solid matter adhering to the inner circumferential surface of the structure. The waste treatment device according to claim 6, characterized in that the solid matter removal device is provided with a water injection device that injects water toward the inner surface of the structure. The waste treatment device according to claim 6, characterized in that the solid matter removal device is provided with a hammer device that strikes the outer peripheral surface of the structure. The waste treatment device according to claim 3, characterized in that the water pipe is made of low alloy steel. The waste treatment device according to claim 3, characterized in that a thermal spray coating made of a material having heat resistance and corrosion resistance is formed on the outer circumferential surface of the water pipe. The waste treatment device according to claim 3, characterized in that the surface of the water pipe that comes into contact with the reformed gas is a polished surface. The boiler comprises:
An upper flange side suspension fin provided on a lower surface of the upper flange;
an upper water tube side suspension fin provided on an outer peripheral surface of an upper portion of the water tube;
a fastening member for fastening the upper flange side suspension fin and the upper water pipe side suspension fin;
Equipped with
5. The waste treatment device of claim 4, wherein said water pipe is suspended from said upper flange. The waste treatment device according to claim 3, characterized in that a flow guide plate is provided at the bottom of the boiler to guide the molten slag that has flowed down the inner circumferential surface of the structure toward the center in the radial direction of the structure and collect it.

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