CN114836242A

CN114836242A - Biomass gasification furnace

Info

Publication number: CN114836242A
Application number: CN202210517029.1A
Authority: CN
Inventors: 刘圣亮
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-05-13
Filing date: 2022-05-13
Publication date: 2022-08-02

Abstract

The invention discloses a biomass gasification furnace, which comprises a furnace body, an air inlet device, an igniter and a purification device, wherein the air inlet device is arranged in the center of the bottom of the furnace body, the igniter is arranged at the middle upper part of the furnace body, and the top of the furnace body is provided with the purification device communicated with an inner cavity of the furnace body. According to the invention, the purifier is arranged, so that the purified combustible gas only has a small amount of tar mist, and meanwhile, the combustible gas can enter the pyrolysis cavity again for pyrolysis, so that a pipeline and a burner are not blocked, the device is green and environment-friendly, the problem of treatment of tar and sewage generated in the gasification process of biomass is solved to the greatest extent, and the production cost is reduced. The produced combustible gas is subjected to multi-channel pyrolysis gasification through the pyrolysis cavity, and the purity of the discharged combustible gas is very high and can reach more than 98%.

Description

Biomass gasification furnace

Technical Field

The invention relates to the technical field of industrial gasification furnace devices, in particular to a biomass gasification furnace.

Background

The straw gas produced by the biomass gasification furnace belongs to green new energy and has strong vitality, the raw materials produced by the plant gas are crop straws, forest waste, edible fungus residues, cattle, sheep and livestock manure and all combustible substances, and the straw gas is an inexhaustible renewable resource, when the existing biomass gasification furnace is used, the tar content is too much, the tar and the waste water need to be separated after cooling and purification, and the tar and the waste water need to be purified by an electric tar precipitator after being treated by a cyclone dust collector and a water film, so the energy consumption is high, the manufacturing cost is high, and the biomass gasification furnace is needed.

Disclosure of Invention

The invention aims to provide a biomass gasification furnace, which achieves the aim of solving the problems in the background technology.

In order to solve the above technical problems and achieve the above technical effects, the present invention is implemented by the following technical contents:

a biomass gasification furnace comprises a furnace body, an air inlet device, an igniter and a purification device, wherein the air inlet device is arranged in the center of the bottom of the furnace body, the igniter is arranged on the middle upper part of the furnace body, and the top of the furnace body is provided with the purification device communicated with an inner cavity of the furnace body.

Further, the furnace body comprises an outer furnace body, an inner furnace body, a partition plate, a furnace opening and an exhaust port; the bottom of the outer furnace body is provided with an ash outlet, the center of the top of the outer furnace body is provided with a furnace opening, the inner wall of the outer furnace body is fixedly provided with an inner furnace body, a gap is reserved between the inner furnace body and the outer furnace body, and the bottom end of the inner furnace body is hermetically connected with the outer furnace body; the inner wall of the outer furnace body is provided with a heat-insulating layer, and a pyrolysis cavity is formed between the heat-insulating layer and the inner furnace body; the even vertical even number piece baffle that is provided with in the pyrolysis intracavity forms the passageway between two adjacent baffles, forms a return stroke between two adjacent passageways and the purifier, communicates between the adjacent return stroke, and the passageway bottom of every return stroke all is equipped with draws the cinder notch, the gas vent setting communicates with gas collection device in last gas return stroke, and the lower part is equipped with the first gas outlet that communicates with the first return stroke in pyrolysis chamber in the interior furnace body.

Furthermore, the purification device comprises a first purifier and a second purifier, the first purifier and the second purifier are provided with a second air outlet pipe at the top end of the first purifier, one end of the air outlet of the second air outlet pipe is communicated with the top of the second purifier, and the other end of the air outlet of the second air outlet pipe extends into 3/4 in the first purifier; a first air inlet pipe is arranged at the top of the second purifier, one air inlet end of the first air inlet pipe is communicated with the top of the first purifier, and the other end of the first air inlet pipe extends downwards to 3/4 inside the second purifier; the side face of the upper end of the first purifier is provided with a first air outlet pipe, the side face of the upper end of the second purifier is provided with a third air outlet pipe, the first air outlet pipe and the third air outlet pipe are communicated with two adjacent channels of each return stroke, the bottoms of the first purifier and the second purifier are respectively provided with a blowoff valve and connected with a blowoff pipeline, and the bottom end of the blowoff pipeline is communicated with the inner furnace body.

Furthermore, a first inspection opening, a second inspection opening and a third inspection opening are formed in the outer furnace body.

Furthermore, the air inlet device comprises a protective cover, a first air pipe, a second air pipe, a first air inlet disc and a second air inlet disc; the protective cover is arranged at the bottom of the outer furnace body, and an upper air chamber and a lower air chamber are arranged in the protective cover; the first air pipe is arranged in the middle of the outer furnace body, the lower end of the first air pipe is connected with the upper air chamber, the upper end of the first air pipe extends into the outer furnace body, the first air inlet disc is fixedly arranged at the upper end of the first air pipe, a second air pipe is arranged in the first air pipe, the lower end of the second air pipe is connected with the lower air chamber, the second air inlet disc is arranged at the upper end of the second air pipe after extending out of the first air inlet disc, and the first air inlet disc and the second air inlet disc are respectively provided with an air outlet;

furthermore, the first air pipe is arranged in the middle of the outer furnace body through a bearing, and the part of the first air pipe extending out of the outer furnace body is connected with a driving shaft of a first motor through a gear mechanism; an inner sleeve is arranged on the outer side of the first air pipe, the lower end of the inner sleeve is fixed with the bottom of the outer furnace body, and the upper end of the inner sleeve is rotatably connected with the first air inlet disc; the outer sleeve is arranged on the outer side of the inner sleeve, and the top of the outer sleeve is fixed with the first air inlet disc; the middle part of the outer sleeve is provided with a slag breaker, and the bottom end of the outer sleeve is provided with a scraper.

Furthermore, the first air inlet disc belongs to an updraft type, and the second air inlet disc belongs to an air return type.

Furthermore, 2-8 groups of igniters are uniformly arranged on the furnace body, and the igniters penetrate through the inner furnace body and the outer furnace body and are arranged on the upper sides of the first air inlet disc and the second air inlet disc and form an angle of 45 degrees; an igniter sleeve is arranged on the periphery of the igniter and welded on the inner furnace body and the outer furnace body.

Furthermore, a blanking device is arranged in the inner furnace body and comprises a first blanking device and a second blanking device, the first blanking device and the second blanking device are thickened high-temperature-resistant steel rings, the first blanking device is arranged on the upper portion of a second air inlet disc, the second blanking device is arranged on the upper portion of the first air inlet disc, the left sides of the first blanking device and the second blanking device are respectively rotatably connected with the inner furnace body, the right sides of the first blanking device and the second blanking device are respectively connected with a first chain wheel and a double-groove wheel outside the furnace body through a second transmission shaft and a third transmission shaft which penetrate through the inner furnace body and the outer furnace body, a transmission chain is arranged between the first chain wheel and the double-groove wheel, and a transmission chain is arranged between the double-groove wheel and a second chain wheel on a second motor.

The invention has the beneficial effects that:

(1) according to the invention, by arranging the purifiers, when the water cooler is used for purification, the purity of the gas cooled by the water cooler is higher, when the number of the purifiers is four, and when two of the purifiers are water-cooled purifiers, the purified combustible gas only contains a small amount of tar mist, and meanwhile, the combustible gas can enter the pyrolysis cavity again for pyrolysis, so that a pipeline and a burner are not blocked, the device is green and environment-friendly, the problem of treatment of tar and sewage generated in the gasification process of biomass is solved to the greatest extent, and the production cost is reduced.

(2) According to the invention, the first air inlet disc and the second air inlet disc are arranged, materials are subjected to cracking gasification reaction on the second air inlet disc, the produced combustible gas contains tar and charcoal, the charcoal can move to the first air inlet disc to perform secondary cracking gasification reaction, so that the content of tar in the produced combustible gas is reduced, and the purity of the discharged combustible gas is very high and can reach more than 98% after multi-channel purification and multi-channel pyrolysis gasification in the pyrolysis cavity.

(3) According to the invention, the first chain wheel, the double grooved wheels, the second chain wheel and the second motor are arranged, the second chain wheel is driven to rotate by the second motor, the double grooved wheels are driven to rotate by the second chain wheel through the chain, the first chain wheel is driven to rotate by the double grooved wheels through the chain, the first blanking device and the second blanking device are driven to turn over in a reciprocating manner through the transmission shaft, the half circle swings up and down to realize blanking, uneven fuel falls and is compacted, the fuel in a gasification layer can not be bridged and burnt out, and the combustible gas in the gasification layer is more stable.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the description below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a front view of the present invention;

FIG. 2 is a front cross-sectional view of the present invention;

FIG. 3 is a schematic view of the air intake device of the present invention;

FIG. 4 is a block diagram of the transmission of the present invention;

fig. 5 is a top sectional view of the present invention.

In the drawings, the components represented by the respective reference numerals are listed below:

1-furnace body, 11-outer furnace body, 111-first inspection port, 112-second inspection port, 113-third inspection port, 12-inner furnace body, 13-furnace bottom plate, 131-ash outlet, 14-furnace port, 15-first air outlet, 16-pyrolysis cavity, 161-partition plate, 162-slag removing port and 17-exhaust port;

2-air inlet device, 21-protective cover, 22-upper air chamber, 23-lower air chamber, 24-first air pipe, 25-second air pipe, 26-first air inlet disc, 27-second air inlet disc, 29 transmission gear, 291-bearing, 281-inner sleeve, 282-outer sleeve, 283-slag breaker, 284-scraper and 34-first motor;

31-a first chain wheel, 32-a second chain wheel, 33-a double grooved wheel and 35-a second motor;

4-a blanking device, 41-a first blanking device, 411-a second transmission shaft, 42-a second blanking device and 421-a third transmission shaft;

5-an igniter;

6-purification device, 61-first purifier, 611-blowdown valve, 612-blowdown pipeline, 62-second purifier;

a-a first air outlet pipe, B-a second air outlet pipe, C-a first air inlet pipe and D-a third air outlet pipe.

Detailed Description

The present invention is further illustrated by the following examples, which are not intended to be limiting in any way, and any modifications or alterations based on the teachings of the present invention are intended to fall within the scope of the present invention.

The invention discloses a biomass gasification furnace, and referring to fig. 1, the biomass gasification furnace comprises a furnace body 1, an air inlet device 2, an igniter 5 and a purification device 6, wherein the air inlet device 2 is arranged in the center of the bottom of the furnace body 1, the igniter 5 is arranged at the middle upper part of the furnace body 1, and the top of the furnace body 1 is provided with the purification device 6 communicated with the inner cavity of the furnace body; the biomass raw material enters the furnace body 1, then the air inlet device 2 starts to supply air into the furnace, the igniter 5 ignites under the ventilation and combustion supporting conditions to enable the biomass raw material to be combusted in the furnace, gas generated by combustion passes through the purification device 6, and substances such as tar and the like in the gas are filtered and removed by the purification device 6, so that high-purity fuel gas is obtained.

Referring to fig. 1-2, the biomass gasification furnace according to claim 1, characterized in that: the furnace body 1 comprises an outer furnace body 11, an inner furnace body 12, a partition plate 13, a furnace mouth 14 and an exhaust port 17; the bottom of the outer furnace body 11 is provided with an ash outlet 131, the center of the top of the outer furnace body 11 is provided with a furnace opening 14, the inner wall of the outer furnace body 11 is fixedly provided with an inner furnace body 12, a gap is reserved between the inner furnace body 12 and the outer furnace body, and the bottom end of the inner furnace body 12 is hermetically connected with the outer furnace body 11; an insulating layer is arranged on the inner wall of the outer furnace body 11, and a pyrolysis cavity 16 is formed between the insulating layer and the inner furnace body 12; an even number of partition plates 13 are uniformly and vertically arranged in the pyrolysis cavity 16, a channel is formed between every two adjacent partition plates 13, a return stroke is formed between every two adjacent channels and the purification device 6, the adjacent return strokes are communicated, the bottom end of each return stroke channel is provided with a slag tapping hole 162, the exhaust port 17 is arranged in the last gas return stroke and communicated with a gas collection device, and the middle lower part of the inner furnace body 12 is provided with a first gas outlet 15 communicated with the first return stroke of the pyrolysis cavity 16;

the pyrolysis chamber 16 can carry out pyrolysis gasification to the gas that the burning produced in the stove, and combustible gas carries out pyrolysis gasification and purification from the return stroke that interior furnace body 12 got into pyrolysis chamber 16 through first gas outlet 15, reduces the tar volume among the combustible gas, and the required heat energy in pyrolysis chamber 16 is by the fuel in the stove to heat the heat that discharges off to interior furnace body 12 in the gasification process of burning.

Referring to fig. 2 and 5, the purification device 6 includes a first purifier 61, a second purifier 62, the first purifier 61 and the second purifier 62, a second air outlet pipe B is arranged at the top end of the first purifier 61, one end of the air outlet of the second air outlet pipe B is communicated with the top of the second purifier 62, and the other end extends into 3/4 in the first purifier 61; a first air inlet pipe C is arranged at the top of the second purifier 62, one air inlet end of the first air inlet pipe C is communicated with the top of the first purifier 61, and the other end of the first air inlet pipe C extends downwards to 3/4 inside the second purifier 62; a first air outlet pipe A is arranged on the side surface of the upper end of the first purifier 61, a third air outlet pipe D is arranged on the side surface of the upper end of the second purifier 62, and the first air outlet pipe A and the third air outlet pipe D are communicated with two adjacent channels of each return stroke; combustible gas enters a return stroke of the pyrolysis cavity 16 from the inner furnace body 12 through the first gas outlet 15, the combustible gas after pyrolysis gasification in the return stroke enters the first purifier 61 through the first gas outlet pipe A for purification, enters the second purifier 62 from the second gas outlet pipe B, returns to a second gas return stroke of the pyrolysis cavity 16 through the third gas outlet pipe D for secondary pyrolysis, heavier gas which does not completely enter the second gas return stroke returns to the first purifier 61 through the first gas inlet pipe C at the bottom end of the second purifier 62 for secondary evolution, then enters the second purifier 62 through the second gas outlet pipe B and is introduced into the second gas in the pyrolysis cavity 16, and the second gas is sequentially subjected to reciprocating cycle pyrolysis;

the bottom parts of the first purifier 61 and the second purifier 62 are respectively provided with a blow-off valve 611 which is connected with a blow-off pipeline 612, and the bottom end of the blow-off pipeline 612 is communicated with the inner furnace body 12; the sewage and tar generated in the purification device enter a sewage discharge pipeline 612 through a sewage discharge valve 611 and then enter the furnace body for secondary pyrolysis and gasification.

Referring to fig. 1, the outer furnace body 11 is provided with a first inspection opening 111, a second inspection opening 112 and a third inspection opening 113, so that the interior of the furnace body can be maintained.

Referring to fig. 2 and 3, the air intake device 2 includes a protective cover 21, a first air duct 24, a second air duct 25, a first air intake plate 26, and a second air intake plate 27;

a protective cover 21 is arranged at the bottom of the outer furnace body 11, and an upper air chamber 22 and a lower air chamber 23 are arranged in the protective cover 21; the first air pipe 24 is arranged in the middle of the outer furnace body 11, the lower end of the first air pipe is connected with the upper air chamber 22, the upper end of the first air pipe extends into the outer furnace body 11, the first air inlet disc 26 is fixedly arranged at the upper end of the first air pipe 24, the second air pipe 25 is arranged in the first air pipe 24, the lower end of the second air pipe 25 is connected with the lower air chamber 23, the second air inlet disc 27 is arranged after the upper end of the second air pipe 25 extends out of the first air inlet disc 26, and the first air inlet disc 26 and the second air inlet disc 27 are respectively provided with an air outlet; when the air intake device 2 supplies air, air enters the first air pipe 24 and the second air pipe 25 through the upper air chamber 22 and the lower air chamber 23, and the air (air) is sent into the first air disc 26 and the second air disc 27 through the first air pipe 24 and the second air pipe 25 to carry out diffusion point combustion supporting on fuel.

The first air pipe 24 is installed in the middle of the outer furnace body 11 through a bearing 291, and the part of the first air pipe 24 extending out of the outer furnace body 11 is connected with a driving shaft of the first motor 34 through a gear mechanism 29; an inner sleeve 281 is arranged on the outer side of the first air pipe 24, the lower end of the inner sleeve 281 is fixed with the bottom of the outer furnace body 11, and the upper end of the inner sleeve 281 is rotatably connected with the first air inlet disc 26; the outer sleeve 282 is arranged outside the inner sleeve 281, and the top of the outer sleeve is fixed with the first air inlet disc 26; a slag breaker 283 is arranged in the middle of the outer sleeve 282, and a scraper 284 is arranged at the bottom end of the outer sleeve 282;

the first motor 34 drives the gear transmission mechanism 29 to rotate, so that the air inlet assembly 2 (except the protective cover 21, the inner sleeve 281, the upper air chamber 22 and the lower air chamber 23) rotates, ash residues gasified by combustion can fall onto the slag breaker 283, are broken and then fall into the bottom of the outer furnace body 11, and are scraped into the ash outlet 131 by the scraper 284 to be discharged.

The first air inlet disc 26 belongs to an updraft type upward air outlet, and the second air inlet disc 27 belongs to an air return type downward air outlet to support combustion of fuel, so that the fuel is cracked between the first air inlet disc 26 and the second air inlet disc 27.

Referring to fig. 1, 2-8 groups of igniters 5 are arranged and uniformly installed on a furnace body 1, and the igniters 5 penetrate through an inner furnace body 12 and an outer furnace body 11 and are arranged on the upper sides of a first air inlet disc 26 and a second air inlet disc 27 and form an angle of 45 degrees; the periphery of the igniter 5 is provided with an igniter 5 sleeve, the igniter 5 sleeve is welded on the inner furnace body 12 and the outer furnace body 11, and when the igniters are set to be 8 groups, the ignition speed can be more than two times faster.

Referring to fig. 2 and 4, the blanking device 4 is installed in the inner furnace body 12 and includes a first blanking device 41 and a second blanking device 42, the first blanking device 41 and the second blanking device 42 are thickened high temperature resistant steel rings, the first blanking device 41 is installed on the upper portion of the second air intake disc 27, the second blanking device 42 is installed on the upper portion of the first air intake disc 26, the left sides of the first blanking device 41 and the second blanking device 42 are respectively rotatably connected with the inner furnace body 12, the right sides of the first blanking device 41 and the second blanking device 42 are respectively connected with the first chain wheel 31 and the double groove wheels 33 outside the furnace body 1 through the second transmission shaft 411 and the third transmission shaft groove wheel 421 penetrating through the inner furnace body 12 and the outer furnace body 11, the transmission chain is installed between the first chain wheel 31 and the double groove wheels 33, and the transmission chain is installed between the double groove wheels 33 and the second chain wheel 31 on the second motor 35; after the raw materials enter the inner furnace body 12, the second motor 35 drives the double grooved pulley 33 and the first chain wheel 31 to rotate through the second chain wheel 32, and the annular first blanking device 41 and the annular second blanking device 42 can rotate in a reciprocating half circle to swing through the second transmission shaft 411 and the third transmission shaft 421, so that the fuel in the gasification layer is scattered and cannot be stacked together to form a bridge and be burnt out, the uneven fuel falls and is compacted, and the combustible gas in the gasification layer is more stable.

The working principle is as follows:

a. feeding: the fuel is added into the furnace from the furnace mouth 14 and reaches the blanking component 4, the transmission component 3 is started, the second motor 35 drives the double grooved pulley 33 and the first chain wheel 31 to rotate through the second chain wheel 32, so that the first blanking device 41 and the second blanking device 42 can rotate in a reciprocating half circle to swing, the fuel in a gasification layer can be scattered and cannot be stacked together to form a bridge and be burnt out, the uneven fuel falls and is compacted, and the combustible gas in the gasification layer is more stable;

b. air supply: air is supplied by the air inlet assembly 2, primary air and secondary air are sprayed into the first air cavity and the second air cavity 23 and the second air cavity 22 through the first air inlet 231 and the second air inlet 221, and enter the first air disc 26 and the second air disc 27 through the first air pipe 24 and the second air pipe 25, so that ignited air (air) is sprayed out of the first air disc 26 and the second air disc 27 respectively;

c. and (3) ignition: igniting the fuel by the first igniter 51 and the second igniter 52, the fuel starting to crack the gas in the furnace, the combustible gas being generated in the reduction layer;

d. and (3) combustion: the first air inlet disc 26 belongs to an updraft type, the reduction layer is subjected to cracking gasification reaction at the upper part of the first air inlet disc 26, the second air inlet disc 27 belongs to a gas return type, the reduction layer is subjected to cracking gasification reaction at the lower part of the second air inlet disc 27 to form two oxidation layers and a reduction layer, the reduction layer is arranged between the first air inlet disc and the second air inlet disc, combustible gas is discharged from the reduction layer between the two oxidation layers, new materials are subjected to cracking gasification reaction on the second air inlet disc 27, the produced combustible gas tar and charcoal can fall into the first air inlet disc 26 to be subjected to secondary cracking gasification reaction, the raw materials are charcoal in the first air inlet disc 26, and the content of the tar in the produced combustible gas is very low;

e. purifying: the combustible gas enters the first purifier 61 for purification after entering the first return stroke of the pyrolysis cavity 16 from the first gas outlet 15, and the sewage tar of the first purifier 61 enters the sewage discharge pipeline 612 through the valve and then enters the reduction layer in the furnace body for secondary cracking gasification;

f. and (3) gasification: the purified gas enters a second purifier 62 for purification, then enters the pyrolysis cavity 16 for second-pass pyrolysis, is sequentially pyrolyzed and gasified in 4-8 pyrolysis cavities 16, and finally is discharged through an exhaust port 17;

g. deslagging: the first motor 34 drives the gear 29 to rotate the air intake assembly 2 except for the inner sleeve 281, the first air cavity 23, the second air cavity 22 and the bearing box 292 of the protective cover 21, so that ash slag gasified by combustion can fall onto the slag breaker 283, is broken and then falls onto the furnace bottom plate 13, and is scraped into the ash outlet 131 by the scraper 284 to be discharged.

The invention utilizes the double-combustion gasification technology to reduce the tar content in the combustible gas, and simultaneously carries out multiple purification and tar wastewater backflow secondary gasification processes, thereby increasing the yield of the combustible gas and improving the heat value of the combustible gas. The multi-channel pyrolysis technology is utilized, so that the combustible gas is purer and can reach more than 98%, no tar sewage is discharged in the whole gasification, purification and pyrolysis processes, the complex tar sewage treatment process is thoroughly solved, the energy is saved, and the environment is protected.

Finally, it is noted that the above-mentioned preferred embodiments illustrate rather than limit the invention, and that, although the invention has been described in detail with reference to the above-mentioned preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the invention as defined by the appended claims.

Claims

1. A biomass gasification furnace is characterized in that: the furnace comprises a furnace body (1), an air inlet device (2), an igniter (5) and a purifying device (6), wherein the air inlet device (2) is arranged in the center of the bottom of the furnace body (1), the igniter (5) is arranged on the middle upper part of the furnace body (1), and the purifying device (6) communicated with an inner cavity of the furnace body (1) is arranged at the top of the furnace body (1).

2. The biomass gasification furnace according to claim 1, wherein: the furnace body (1) comprises an outer furnace body (11), an inner furnace body (12), a partition plate (13), a furnace mouth (14) and an exhaust port (17);

an ash outlet (131) is arranged at the bottom of the outer furnace body (11), a furnace opening (14) is arranged at the center of the top of the outer furnace body (11), an inner furnace body (12) is fixedly arranged on the inner wall of the outer furnace body (11), a gap is reserved between the inner furnace body (12) and the outer furnace body, and the bottom end of the inner furnace body (12) is hermetically connected with the outer furnace body (11); the inner wall of the outer furnace body (11) is provided with a heat-insulating layer, and a pyrolysis cavity (16) is formed between the heat-insulating layer and the inner furnace body (12); even vertical even piece baffle (13) that are provided with in pyrolysis chamber (16), form the passageway between two adjacent baffles (13), form a return stroke between two adjacent passageways and purifier (6), communicate between the adjacent return stroke, the passageway bottom of every return stroke all is equipped with draws slag hole (162), gas vent (17) set up in last gas return stroke with gas collection device intercommunication, lower part is equipped with first gas outlet (15) that communicate with pyrolysis chamber (16) first return stroke in interior furnace body (12).

3. The biomass gasification furnace according to claim 2, wherein: the purification device (6) comprises a first purifier (61) and a second purifier (62), the first purifier (61) and the second purifier (62) are arranged, a second air outlet pipe (B) is arranged at the top end of the first purifier (61), one end of the air outlet of the second air outlet pipe (B) is communicated with the top of the second purifier (62), and the other end of the air outlet of the second air outlet pipe (B) extends downwards to 3/4 inside the first purifier (61); a first air inlet pipe (C) is arranged at the top of the second purifier (62), one air inlet end of the first air inlet pipe (C) is communicated with the top of the first purifier (61), and the other end of the first air inlet pipe (C) extends downwards to 3/4 inside the second purifier (62); first clarifier (61) upper end side is equipped with first outlet duct (A), and second clarifier (62) upper end side is equipped with third outlet duct (D), and first outlet duct (A) and third outlet duct (D) communicate with two adjacent passageways of every return stroke, and first clarifier (61) and second clarifier (62) bottom all are equipped with blowoff valve (611) and are connected with sewage pipes (612), and sewage pipes (612) bottom and interior furnace body (12) intercommunication.

4. The biomass gasification furnace according to claim 2, wherein: the outer furnace body (11) is provided with a first inspection opening (111), a second inspection opening (112) and a third inspection opening (113).

5. The biomass gasification furnace according to claim 1, wherein: the air inlet device (2) comprises a protective cover (21), a first air pipe (24), a second air pipe (25), a first air inlet disc (26) and a second air inlet disc (27);

the protective cover (21) is arranged at the bottom of the outer furnace body (11), and an upper air chamber (22) and a lower air chamber (23) are arranged in the protective cover (21); first tuber pipe (24) are installed in the middle part of outer furnace body (11), and its lower extreme is connected with last blast chamber (22), and the upper end stretches into in outer furnace body (11), and first air-supply tray (26) fixed mounting is in the upper end of first tuber pipe (24), is provided with second tuber pipe (25) in first tuber pipe (24), and second tuber pipe (25) lower extreme is connected with lower blast chamber (23), installs second air-supply tray (27) after second tuber pipe (25) upper end stretches out first air-supply tray (26), and first air-supply tray (26) and second air-supply tray (27) respectively are equipped with the air outlet.

6. The biomass gasification furnace according to claim 5, wherein: the first air pipe (24) is arranged in the middle of the outer furnace body (11) through a bearing (291), and the part of the first air pipe (24) extending out of the outer furnace body (11) is connected with a driving shaft of a first motor (34) through a gear mechanism (29); an inner sleeve (281) is arranged on the outer side of the first air pipe (24), the lower end of the inner sleeve (281) is fixed with the bottom of the outer furnace body (11), and the upper end of the inner sleeve (281) is rotatably connected with the first air inlet disc (26); the outer sleeve (282) is arranged outside the inner sleeve (281), and the top of the outer sleeve is fixed with the first air inlet disc (26); the middle part of the outer sleeve (282) is provided with a slag breaker (283), and the bottom end of the outer sleeve (282) is provided with a scraper (284).

7. The biomass gasification furnace according to claim 5, wherein: the first air inlet disc (26) belongs to an updraft type, and the second air inlet disc (27) belongs to an air return type.

8. The biomass gasification furnace according to any one of claims 1 to 5, wherein: 2-8 groups of igniters (5) are arranged and uniformly arranged on the furnace body (1), and the igniters (5) penetrate through the inner furnace body (12) and the outer furnace body (11) and are arranged on the upper sides of the first air inlet disc (26) and the second air inlet disc (27) and form an angle of 45 degrees; an igniter (5) sleeve is arranged on the periphery of the igniter (5), and the igniter (5) sleeve is welded on the inner furnace body (12) and the outer furnace body (11).

9. The biomass gasification furnace according to claim 1, wherein: the blanking device (4) is installed in the inner furnace body (12) and comprises a first blanking device (41) and a second blanking device (42), the first blanking device (41) and the second blanking device (42) are thickened high-temperature-resistant steel rings, the first blanking device (41) is arranged on the upper portion of a second air inlet disc (27), the second blanking device (42) is arranged on the upper portion of a first air inlet disc (26), the left sides of the first blanking device (41) and the second blanking device (42) are respectively connected with the inner furnace body (12) in a rotating mode, the right sides of the first blanking device and the second blanking device are respectively connected with a first chain wheel (31) and a double groove wheel (33) outside the furnace body (1) through a second transmission shaft (411) and a third transmission shaft (421) penetrating through the inner furnace body (12) and the outer furnace body (11), a transmission chain is installed between the first chain wheel (31) and the double groove wheel (33), and a transmission chain is installed between the double groove wheel (33) and a second chain (31) on a second motor (35).