JP2022132992A - Gasification furnace and power generation system - Google Patents

Abstract

To provide a gasification furnace in which a primary combustion chamber and a secondary combustion chamber, that overlap vertically, are formed inside a gasification furnace body, and a wood gas is generated from wood chips, wherein the gasification furnace makes it possible to take out the wood gas while suppressing temperature drop of the wood gas generated in the secondary combustion chamber.SOLUTION: A gasification furnace 2 has a primary combustion chamber 10 and a secondary combustion chamber 11 that are formed inside a gasification furnace body 12 and overlap vertically. One end of a taking-out pipe 15 for taking out a wood gas generated in the secondary combustion chamber 11 is connected to an upper surface side of the secondary combustion chamber 11, and a portion of the taking-out pipe 15 is arranged inside the primary combustion chamber 10. The wood gas taken out from the secondary combustion chamber 11 passes through a part of the taking-out pipe 15 arranged inside the primary combustion chamber 10 where wood chips are heated.SELECTED DRAWING: Figure 1

Description

The present invention relates to a gasifier for producing wood gas from wood chips. The present invention also relates to a power generation system including this gasification furnace.

Conventionally, a gasification furnace for carbonizing and gasifying biomass resources is known (see, for example, Patent Document 1). The gasification furnace described in Patent Literature 1 includes a furnace body, a raw material charging section connected to the upper part of the furnace body, and a punching plate that vertically partitions a storage section in the furnace body. The raw material charging section charges raw materials such as chips and pellets into the storage section of the furnace main body. In this gasification furnace, the size of the opening of the punching plate is smaller than the size of the raw material at the time of charging so that the raw material charged into the container is loaded on the punching plate. The raw material that has been carbonized in the container and turned into fine grains passes through the opening of the punching plate and falls from the punching plate.

In the gasification furnace described in Patent Literature 1, the area above the punching plate in the storage section serves as the primary combustion chamber (first gasification chamber), and the area below the punching plate in the storage section. is a secondary combustion chamber (second gasification chamber). The raw material that is carbonized in the primary combustion chamber and becomes fine grains falls from the punching plate and accumulates in the secondary combustion chamber. The gasification furnace described in Patent Literature 1 generates fuel gas by further dry-distilling the carbide deposited in the secondary combustion chamber. An intake side of a blower is connected to a side surface of the secondary combustion chamber. The blower sends fuel gas generated in the secondary combustion chamber toward a gas turbine or the like.

JP 2017-119771 A

In a gasification furnace for generating wood gas from wood chips, the inventor of the present application has a primary combustion chamber and a secondary combustion chamber that overlap vertically like the gasification furnace described in Patent Document 1. We are considering forming it inside the furnace body. Further, the inventor of the present application has found that the gasification furnace can be used in a power generation system comprising a boiler that burns woody gas to generate steam, and a generator having a steam turbine that is rotated by the steam generated by the boiler. are considering. In this power generation system, the woody gas produced in the gasification furnace is directly supplied to the boiler.

According to studies by the inventors of the present application, in this power generation system, as the temperature of the woody gas supplied to the boiler decreases, it becomes more difficult to burn the woody gas in the gas burner of the boiler. Therefore, it is preferable to take out the woody gas from the gasification furnace and supply it to the boiler while suppressing the decrease in the temperature of the woody gas generated in the secondary combustion chamber.

Accordingly, an object of the present invention is to provide a gasifier in which a primary combustion chamber and a secondary combustion chamber that overlap vertically are formed inside a gasifier body and in which wood gas is generated from wood chips. To provide a gasification furnace capable of extracting woody gas while suppressing a decrease in temperature of the woody gas generated in a chamber. Another object of the present invention is to provide a power generation system including this gasification furnace.

In order to solve the above problems, the gasifier of the present invention is a gasifier for producing wood gas from wood chips, and a gasifier main body in which a primary combustion chamber and a secondary combustion chamber are formed. a partition member arranged inside the gasifier main body and dividing the inside of the gasifier main body into a primary combustion chamber and a secondary combustion chamber; A primary combustion chamber is provided above the partition member inside the gasifier main body, and a secondary combustion chamber is provided below the partition member inside the gasifier main body. The member is formed with a plurality of passage holes through which the carbide produced in the primary combustion chamber passes toward the secondary combustion chamber. Woody gas is generated using the carbide, one end of the extraction pipe is connected to the upper surface side of the secondary combustion chamber, a part of the extraction pipe is arranged inside the primary combustion chamber, and the secondary combustion chamber The woody gas extracted from the primary combustion chamber passes through a part of the extraction pipe arranged inside the primary combustion chamber.

In the gasification furnace of the present invention, one end of the take-out pipe is connected to the upper surface side of the secondary combustion chamber, and part of the take-out pipe is arranged inside the primary combustion chamber. Further, in the present invention, the temperature of the wood gas extracted from the secondary combustion chamber is higher than the temperature inside the primary combustion chamber where the wood chips are heated (that is, the temperature outside the main body of the gasifier). inside the primary combustion chamber). Therefore, in the present invention, compared with the case where the entire take-out pipe is arranged outside the gasifier main body, the temperature of the woody gas generated in the secondary combustion chamber can be suppressed while suppressing the temperature of the gasifier. wood gas can be extracted from

Further, in the present invention, since it is possible to suppress the decrease in the temperature of the woody gas generated in the secondary combustion chamber by using the primary combustion chamber, the temperature of the woody gas generated in the secondary combustion chamber can be suppressed. There is no need to separately provide a configuration for suppressing temperature drop. Therefore, in the present invention, even if it is possible to suppress the decrease in the temperature of the woody gas generated in the secondary combustion chamber, it is possible to simplify the configuration of the gasifier.

In the present invention, it is preferable that a portion of the extraction pipe arranged inside the primary combustion chamber is arranged in the center of the primary combustion chamber. With this configuration, a part of the extraction pipe arranged inside the primary combustion chamber is located inside the primary combustion chamber, for example, compared to the case where it is arranged at the end of the primary combustion chamber. It is possible to effectively suppress a decrease in the temperature of the woody gas passing through part of the arranged extraction pipe.

In the present invention, the gasifier is provided with a supply pipe for supplying the primary product gas to the secondary combustion chamber, and one end of the supply pipe extends tangentially to the inner wall of the secondary combustion chamber. is preferably connected to the secondary combustion chamber from the outer peripheral side of the secondary combustion chamber so as to supply the secondary combustion chamber. With this configuration, it becomes possible to swirl the carbide and the primary produced gas in the secondary combustion chamber. Therefore, according to the studies of the inventors of the present application, it becomes possible to raise the temperature of the secondary combustion chamber, and as a result, it becomes possible to take out woody gas with a lower moisture content from the gasification furnace. Therefore, when the woody gas is supplied to the boiler, it becomes easier to burn the woody gas in the gas burner of the boiler.

In the present invention, since one end of the take-out pipe is connected to the upper surface side of the secondary combustion chamber, the fuel is supplied from the outer peripheral side of the secondary combustion chamber to the secondary combustion chamber without considering the arrangement of the take-out pipe. It becomes possible to connect the pipes for Therefore, even if the supply pipe is connected to the secondary combustion chamber from the outer peripheral side of the secondary combustion chamber, the supply pipe can be easily connected to the secondary combustion chamber.

The gasification furnace of the present invention comprises a boiler supplied with the wood gas produced in the gasification furnace and combusting the wood gas to produce steam, and a generator having a steam turbine rotated by the steam produced by the boiler. It can be used for a power generation system comprising In this power generation system, it is possible to extract wood gas from the gasification furnace while suppressing the temperature drop of the wood gas generated in the secondary combustion chamber, so it is easy to burn wood gas in the boiler's gas combustor. Become.

As described above, according to the present invention, in a gasification furnace in which a primary combustion chamber and a secondary combustion chamber that overlap vertically are formed inside a gasification furnace body and wood gas is generated from wood chips, the secondary combustion chamber is It is possible to take out the woody gas from the gasification furnace while suppressing the decrease in the temperature of the woody gas generated in the combustion chamber.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic for demonstrating the structure of the electric power generation system concerning embodiment of this invention. FIG. 2 is a cross-sectional view for explaining the configuration of the lower end portion of the gasification furnace shown in FIG. 1;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Configuration of power generation system and gasification furnace)
FIG. 1 is a schematic diagram for explaining the configuration of a power generation system 1 according to an embodiment of the invention. FIG. 2 is a cross-sectional view for explaining the configuration of the lower end portion of the gasification furnace 2 shown in FIG.

A power generation system 1 of this embodiment includes a gasification furnace 2 , a boiler 3 , and a generator 4 . The gasification furnace 2 carbonizes the wood chips to generate wood gas from the wood chips. The wood chips of this embodiment are wood chips made of wood pulverized into chips. The size of the wood chip is about several millimeters. The boiler 3 is supplied with woody gas produced in the gasification furnace 2 . Specifically, the woody gas generated in the gasification furnace 2 is directly supplied to the boiler 3 . The boiler 3 burns woody gas to generate steam. The boiler 3 includes a gas combustor 5 and the like for burning wood gas. Steam generated in the boiler 3 is supplied to the generator 4 . The power generator 4 includes a steam turbine 6 and the like that are rotated by steam generated by the boiler 3 .

The gasification furnace 2 includes a gasification furnace body 12 inside which a primary combustion chamber 10 and a secondary combustion chamber 11 are formed, and a partition member 13 arranged inside the gasification furnace body 12 . The gasification furnace main body 12 is formed in a bottomed cylindrical shape having a bottom. The gasification furnace main body 12 is, for example, cylindrical. Alternatively, the gasification furnace main body 12 is formed in a polygonal tubular shape such as an octagonal tubular shape. A water cooling jacket (not shown) for cooling the gasifier body 12 is formed on the outer peripheral side of the gasifier body 12 .

The partition member 13 is formed in a flat plate shape. The partition member 13 partitions the interior of the gasification furnace body 12 in the vertical direction. In the gasifier main body 12, the upper side of the partition member 13 inside the gasifier main body 12 is the primary combustion chamber 10, and the lower side of the partition member 13 inside the gasifier main body 12 is the secondary combustion chamber. Room 11. That is, the partition member 13 partitions the interior of the gasifier body 12 into the primary combustion chamber 10 and the secondary combustion chamber 11, and the interior of the gasifier body 12 includes primary combustion chambers that overlap vertically. 10 and a secondary combustion chamber 11 are formed. A second combustion chamber 11 is arranged below the primary combustion chamber 10 .

Wood chips are supplied to the primary combustion chamber 10 from above. In the primary combustion chamber 10, the wood chips are heated, for example, at about 300-600.degree. In the primary combustion chamber 10, a carbonized material composed of carbonized wood chips and a primary product gas are produced. A lower end portion of the primary combustion chamber 10 is filled with carbide. In the primary combustion chamber 10, wood chips in the process of carbonization and wood chips before carbonization are filled above the carbonized material. The partition member 13 is, for example, a punching metal, and has a plurality of passage holes through which the carbide produced in the primary combustion chamber 10 passes toward the secondary combustion chamber 11 . The passage hole penetrates the partition member 13 in the vertical direction. The shape of the through hole is circular, oval, rectangular, or the like.

Charcoal produced in the primary combustion chamber 10 passes through the passage hole of the partition member 13 by its own weight and falls into the secondary combustion chamber 11 . In the secondary combustion chamber 11, the carbide produced in the primary combustion chamber 10 is heated, for example, to about 1000-1200.degree. A primary product gas produced in the primary combustion chamber 10 is supplied to the secondary combustion chamber 11 . In the secondary combustion chamber 11, woody gas is produced using the carbide and the primary produced gas. Specifically, in the secondary combustion chamber 11, woody gas is produced from the carbide and the primary produced gas.

The gasification furnace 2 also includes a chip storage section 14 that stores wood chips to be supplied to the gasification furnace main body 12, a take-out pipe 15 for taking out the wood gas generated in the secondary combustion chamber 11, A supply pipe 16 for supplying the primary product gas produced in the primary combustion chamber 10 to the secondary combustion chamber 11 is provided. The gasification furnace 2 of this embodiment includes one take-out pipe 15 and one supply pipe 16 .

The chip accommodating portion 14 is formed in a tubular shape. The chip housing portion 14 is arranged on the upper side of the gasification furnace main body 12 , and the lower end of the chip housing portion 14 is connected to the upper end of the gasification furnace main body 12 . Wood chips are supplied to the chip storage portion 14 from above. Specifically, wood chips pulverized by a pulverizer are supplied to the chip storage section 14 from above by a conveyor or the like. The wood chips stored in the chip storage portion 14 are sequentially supplied to the gasification furnace main body 12 by their own weight.

The extraction pipe 15 is arranged between the secondary combustion chamber 11 and the gas combustor 5 of the boiler 3 . That is, one end of the extraction pipe 15 is connected to the secondary combustion chamber 11 and the other end of the extraction pipe 15 is connected to the gas combustor 5 . One end of the extraction pipe 15 is connected to the upper surface side of the secondary combustion chamber 11 . The extraction pipe 15 is routed upward from the secondary combustion chamber 11 and is routed above the upper end of the gasification furnace body 12 .

A part of the extraction pipe 15 is arranged inside the primary combustion chamber 10 and inside the chip accommodating portion 14 . Specifically, one end of the extraction pipe 15 is connected to the center of the secondary combustion chamber 11, and a portion of the extraction pipe 15 disposed inside the primary combustion chamber 10 is connected to the primary combustion chamber 10. is placed in the center of A part of the take-out pipe 15 arranged inside the chip accommodating portion 14 is arranged in the center of the chip accommodating portion 14 .

The woody gas taken out from the secondary combustion chamber 11 passes through a part of the take-out pipe 15 arranged inside the primary combustion chamber 10 and also through the take-out pipe 15 arranged inside the chip storage section 14 . pass through some. That is, the woody gas extracted from the secondary combustion chamber 11 passes through the interior of the primary combustion chamber 10 and the interior of the chip storage section 14 , and then is extracted from the gasification furnace 2 . The inner diameter of the extraction pipe 15 is about 1/5 of the inner diameter of the gasifier body 12 . An air blower for sending the woody gas generated in the secondary combustion chamber 11 to the gas burner 5 is arranged in the middle of the extraction pipe 15 .

The supply pipe 16 is arranged between the secondary combustion chamber 11 and the primary combustion chamber 10 . That is, one end of the supply pipe 16 is connected to the secondary combustion chamber 11 and the other end of the supply pipe 16 is connected to the primary combustion chamber 10 . One end of the supply pipe 16 is connected to the secondary combustion chamber 11 from the outer peripheral side of the secondary combustion chamber 11 . Specifically, one end of the supply pipe 16 is connected to the secondary combustion chamber 11 so that the primary product gas is supplied in the tangential direction of the inner wall of the secondary combustion chamber 11 (the direction indicated by arrow V in FIG. 2). It is connected to the secondary combustion chamber 11 from the outer peripheral side. The other end of the supply pipe 16 is connected to the primary combustion chamber 10 from the outer peripheral side of the primary combustion chamber 10 .

An air blower 17 that sends the primary gas generated in the primary combustion chamber 10 to the second combustion chamber 11 is arranged in the middle of the supply pipe 16 . In the secondary combustion chamber 11, the primary product gas is supplied tangentially to the inner wall of the secondary combustion chamber 11, as described above. Therefore, in the secondary combustion chamber 11, the carbide and the primary produced gas swirl. That is, in the secondary combustion chamber 11, the carbide and the primary produced gas are swirled and burned.

(Main effects of this form)
As described above, in this embodiment, one end of the extraction pipe 15 is connected to the upper surface side of the secondary combustion chamber 11, and a part of the extraction pipe 15 is arranged inside the primary combustion chamber 10. ing. In this embodiment, the wood gas taken out from the secondary combustion chamber 11 has a higher temperature than the inside of the primary combustion chamber 10 where the wood chips are heated (that is, the outside of the gasifier main body 12). It passes through a part of the take-out pipe 15 located inside the elevated primary combustion chamber 10). Therefore, in this embodiment, compared with the case where the entire extraction pipe 15 is arranged outside the gasifier main body 12, the decrease in the temperature of the woody gas generated in the secondary combustion chamber 11 is suppressed. It becomes possible to take out the woody gas from the gasification furnace 2 . Therefore, in this embodiment, the gas burner 5 of the boiler 3 can easily burn woody gas.

In addition, in this embodiment, since it is possible to suppress the decrease in the temperature of the woody gas generated in the secondary combustion chamber 11 by using the primary combustion chamber 10, the temperature of the woody gas generated in the secondary combustion chamber 11 There is no need to separately provide a configuration for suppressing a decrease in the temperature of the woody gas. Therefore, in this embodiment, even if it is possible to suppress the decrease in the temperature of the woody gas generated in the secondary combustion chamber 11, the configuration of the gasification furnace 2 can be simplified.

In this embodiment, part of the extraction pipe 15 arranged inside the primary combustion chamber 10 is arranged at the center of the primary combustion chamber 10 . Therefore, in this embodiment, compared to the case where a part of the extraction pipe 15 arranged inside the primary combustion chamber 10 is arranged, for example, at the end of the primary combustion chamber 10, the primary combustion chamber It is possible to effectively suppress a decrease in the temperature of the woody gas passing through a portion of the extraction pipe 15 arranged inside 10 .

In this embodiment, one end of the supply pipe 16 is connected to the secondary combustion chamber 11 from the outer peripheral side of the secondary combustion chamber 11 so that the primary generated gas is supplied in the tangential direction of the inner wall of the secondary combustion chamber 11. In the secondary combustion chamber 11, the carbide and the primary produced gas are swirled and burned. Therefore, according to the study of the inventor of the present application, in this embodiment, it is possible to increase the temperature of the secondary combustion chamber 11, and as a result, it is possible to take out woody gas with a lower moisture content from the gasification furnace 2. Become. Therefore, in this embodiment, the gas combustor 5 of the boiler 3 can more easily burn the woody gas.

In this embodiment, since one end of the extraction pipe 15 is connected to the upper surface side of the secondary combustion chamber 11, the secondary combustion chamber 11 can be discharged from the outer peripheral side of the secondary combustion chamber 11 without considering the arrangement of the extraction pipe 15. It becomes possible to connect the supply pipe 16 to the combustion chamber 11 . Therefore, in this embodiment, even if the supply pipe 16 is connected to the secondary combustion chamber 11 from the outer peripheral side of the secondary combustion chamber 11 , the supply pipe 16 can be easily connected to the secondary combustion chamber 11 .

(Other embodiments)
Compressed air may be supplied to the secondary combustion chamber 11 in the form described above. In this case, one end of the air supply pipe for supplying compressed air is connected to the secondary combustion chamber 11 from the outer peripheral side of the secondary combustion chamber 11 so that the compressed air is supplied in a tangential direction to the inner wall of the secondary combustion chamber 11, for example. It is connected to the combustion chamber 11. Also, in this case, for example, two air supply pipes are connected to the secondary combustion chamber 11 at a pitch of 180° with respect to the center of the secondary combustion chamber 11 .

In the embodiment described above, the gasification furnace 2 may have a plurality of extraction pipes 15 . Moreover, in the embodiment described above, the gasification furnace 2 may be provided with a plurality of supply pipes 16 . Further, in the above-described embodiment, a part of the extraction pipe 15 arranged inside the primary combustion chamber 10 may be arranged at a position shifted from the center of the primary combustion chamber 10 . Furthermore, in the above-described embodiment, one end of the supply pipe 16 extends two distances from the outer peripheral side of the secondary combustion chamber 11 so that the primary produced gas is supplied in a direction deviated from the tangential direction of the inner wall of the secondary combustion chamber 11 . It may be connected to the secondary combustion chamber 11 .

1 Power Generation System 2 Gasification Furnace 3 Boiler 4 Generator 6 Steam Turbine 10 Primary Combustion Chamber 11 Secondary Combustion Chamber 12 Gasification Furnace Main Body 13 Partition Member 15 Extraction Pipe 16 Supply Pipe

Claims (4)

In a gasification furnace for producing wood gas from wood chips,
a gasifier body in which a primary combustion chamber and a secondary combustion chamber are formed; and a take-out pipe for taking out the woody gas generated in the secondary combustion chamber,
The upper side of the partition member inside the gasification furnace main body is the primary combustion chamber,
Inside the gasification furnace main body, the lower side of the partition member is the secondary combustion chamber,
The partition member is formed with a plurality of passage holes through which the carbide generated in the primary combustion chamber passes toward the secondary combustion chamber,
In the secondary combustion chamber, the woody gas is generated using the primary gas generated in the primary combustion chamber and the carbide,
one end of the extraction pipe is connected to the upper surface side of the secondary combustion chamber,
A part of the extraction pipe is arranged inside the primary combustion chamber,
The gasification furnace, wherein the woody gas extracted from the secondary combustion chamber passes through a part of the extraction pipe arranged inside the primary combustion chamber. 2. The gasification furnace according to claim 1, wherein a portion of said take-out pipe arranged inside said primary combustion chamber is arranged in the center of said primary combustion chamber. A supply pipe for supplying the primary generated gas to the secondary combustion chamber,
One end of the supply pipe is connected to the secondary combustion chamber from the outer peripheral side of the secondary combustion chamber so that the primary generated gas is supplied in a tangential direction to the inner wall of the secondary combustion chamber. 3. The gasification furnace according to claim 1 or 2. 4. The gasification furnace according to any one of claims 1 to 3, a boiler supplied with the woody gas generated in the gasification furnace and burning the woody gas to generate steam, and steam generated by the boiler. and a generator having a steam turbine rotated by the generated steam.

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