阅读说明：本技术 一种回收干煤粉余热的废锅气化装置及方法 (Waste boiler gasification device and method for recovering waste heat of dry pulverized coal ) 是由 张镓铄 马丹丹 夏支文 蔡力宏 匡建平 张亚宁 马钊 杜常宗 袁继禹 白云波 陈 于 2020-06-12 设计创作，主要内容包括：一种回收干煤粉余热的废锅气化装置及方法,该装置包括壳体,壳体内部自上而下设有相互连通的燃烧室和辐射废锅,燃烧室顶端安装有顶置燃烧器,燃烧室两侧对称安装有2N个侧置燃烧器,燃烧室底部开设有渣口；辐射废锅与渣口下端连通,辐射废锅内部从内向外分别间隔开且平行设置有第一级水冷壁和第二级水冷壁,第一级水冷壁下方安装有降温喷头,辐射废锅和壳体底部开设有排渣口；辐射废锅上部侧面开设有合成气出口,合成气出口处连接有输气导管,输气导管的另一端与对流废锅相连通。本申请采用辐射废锅加对流废锅的设计,辐射废锅为两层水冷壁有上升的二次通道与对流废锅相结合,能最大限度的回收高温合成气的显热,热量利用率高,工艺简单。(A waste boiler gasification device and method for recovering waste heat of dry pulverized coal comprises a shell, wherein a combustion chamber and a radiation waste boiler which are mutually communicated are arranged in the shell from top to bottom, a top-mounted burner is arranged at the top end of the combustion chamber, 2N side-mounted burners are symmetrically arranged on two sides of the combustion chamber, and a slag hole is formed in the bottom of the combustion chamber; the radiation waste boiler is communicated with the lower end of the slag hole, a first-stage water-cooled wall and a second-stage water-cooled wall are respectively arranged in the radiation waste boiler from inside to outside in a spaced and parallel mode, a cooling spray head is installed below the first-stage water-cooled wall, and slag discharge holes are formed in the radiation waste boiler and the bottom of the shell; the side surface of the upper part of the radiation waste boiler is provided with a synthesis gas outlet, the synthesis gas outlet is connected with a gas transmission conduit, and the other end of the gas transmission conduit is communicated with the convection waste boiler. The design that this application adopted radiation waste boiler to add convection current waste boiler, the radiation waste boiler has the secondary passageway that rises to combine together with the waste boiler of convection current for two-layer water-cooling wall, and the sensible heat of the high temperature synthesis gas of ability furthest of retrieving, heat utilization rate is high, simple process.)

1. The waste boiler gasification device for recovering the waste heat of the dry pulverized coal is characterized by comprising a shell (7), wherein a combustion chamber (3) and a radiation waste boiler (5) which are communicated with each other are arranged in the shell (7) from top to bottom, an overhead burner (1) is installed at the top end of the combustion chamber (3), 2N (N is more than or equal to 1) side burners (2) are symmetrically installed on two sides of the combustion chamber (3), and a slag hole (4) is formed in the bottom of the combustion chamber (3); the radiation waste pot (5) is communicated with the lower end of the slag hole (4), a primary water-cooled wall (6) and a secondary water-cooled wall (8) are respectively arranged in the radiation waste pot (5) from inside to outside in a spaced and parallel mode, a cooling spray head (9) is installed below the primary water-cooled wall (6), and slag discharge holes (10) are formed in the bottoms of the radiation waste pot (5) and the shell (7); and a synthesis gas outlet is formed in the side surface of the upper part of the radiation waste boiler (5), a gas transmission conduit (11) is connected to the synthesis gas outlet, and the other end of the gas transmission conduit (11) is communicated with the convection waste boiler (12).

2. The waste boiler gasification device for recovering the waste heat of the dry pulverized coal as claimed in claim 1, wherein the first stage water-cooled wall (6) and the second stage water-cooled wall (8) are both cylindrical water-cooled walls.

3. The waste pot gasification device for recovering the waste heat of the dry pulverized coal as claimed in claim 1, wherein the first stage water-cooling wall (6) is a combined structure of a cylindrical water-cooling wall (61) and a fin water-cooling wall (62), wherein the fin water-cooling wall (62) is arranged inside the cylindrical water-cooling wall (61) of the first stage water-cooling wall (6) or between the first stage water-cooling wall (6) and the second stage water-cooling wall (8), and the second stage water-cooling wall (8) is a cylindrical water-cooling wall.

4. The waste pot gasification device for recovering the waste heat of the dry pulverized coal as claimed in claim 3, wherein the fin water-cooled walls (62) are uniformly distributed along the radial direction of the radiation waste pot (5), and the fin water-cooled walls (62) are arranged in 4-24 groups.

5. The waste boiler gasification device for recovering the waste heat of the dry pulverized coal as claimed in claim 1, wherein the upper end of the first-stage water-cooled wall (6) is connected with the upper end of the radiation waste boiler (5); the second-stage water-cooled wall (8) is arranged on the outer side of the first-stage water-cooled wall (6) and parallel to the first-stage water-cooled wall (6), the distance between the inner wall of the second-stage water-cooled wall (8) and the outer wall of the first-stage water-cooled wall (6) is 0.2-2.0 meters, the upper end of the second-stage water-cooled wall (8) is flush with the lower end of the synthesis gas outlet, and the lower end of the second-stage water-cooled wall (8) is compared with the lower end of the first-stage water-cooled wall (6) and extends downwards for 0.2-2.0 meters in.

6. The waste boiler gasification device for recovering the waste heat of the dry pulverized coal as claimed in claim 1, wherein the cooling spray nozzles (9) are installed at the lower part of the shell (7), the cooling spray nozzles (9) are arranged at 0.1-2.0 meters below the first-stage water wall (6), the cooling spray nozzles (9) are arranged in at least one layer, and 2-50 spray nozzles are uniformly distributed along the circumference of the lower end of the radiation waste boiler (5) on each layer.

7. The waste boiler gasification device for recovering the waste heat of the dry pulverized coal as claimed in claim 1, wherein the gas transmission conduit (11) is horizontally arranged or obliquely arranged downwards, and a spiral coil water-cooled wall or a refractory material is arranged in the gas transmission conduit (11).

8. The waste boiler gasification device for recovering the waste heat of the dry pulverized coal as claimed in claim 1, wherein the convection waste boiler (12) adopts a structure of a third-stage cylindrical water-cooled wall and 3-20 groups of spiral coil water-cooled wall tubes, 2-10 circles of water-cooled walls are arranged on a spiral tube of each group of spiral coil water-cooled walls, and the spiral coil water-cooled walls are positioned inside the third-stage cylindrical water-cooled walls.

9. The gasification method of the waste boiler gasification device for recovering the waste heat of the dry coal powder according to any one of claims 1 to 8, characterized in that the dry coal powder is injected into the combustion chamber (3) through the overhead burner (1) or the side burner (2) and undergoes an oxidation reaction in the combustion chamber (3) with the oxygen introduced through the overhead burner (1) to generate crude synthesis gas and ash with the temperature of 1300 ℃ to 1700 ℃; the raw synthesis gas and the ash slag enter the radiation waste boiler (5) through the slag hole (4), firstly pass through the first-stage water-cooled wall (6) for primary heat recovery, the raw synthesis gas and the ash slag reach the bottom of the radiation waste boiler (5) from top to bottom along the first-stage water-cooled wall (6), and are subjected to chilling cooling by the cooling nozzle (9), wherein chilling media can adopt gas or chilling water, the chilled synthesis gas reaches a temperature between 300 and 1000 ℃, the ash slag enters the bottom of the radiation waste boiler (5), is cooled to a temperature below 250 ℃, and is discharged through the slag discharge hole (10); the chilled synthesis gas enters a gap between the first-stage water-cooled wall (6) and the second-stage water-cooled wall (8) for secondary heat recovery; after the two heat exchanges, the crude synthesis gas is cooled to be below 800 ℃, then enters the convection waste boiler (12) through the gas transmission guide pipe (11) to carry out the third heat recovery, and finally the crude synthesis gas is cooled to be 200-400 ℃, thus completing the recovery of the waste heat of the dry coal powder.

Technical Field

The application relates to the technical field of gasification furnaces, in particular to a waste boiler gasification device and method for recovering waste heat of dry coal powder.

Background

The efficient and clean utilization of coal is a necessary strategic choice for economic and social sustainable development, and is an important basis for ensuring stable and reliable supply of energy and sustainable development. In the clean and efficient utilization of coal, the coal gasification technology occupies a core position, and the dry coal powder pressurized entrained flow bed gasification technology becomes a mainstream technology for industrial operation due to the advantages of wide coal type adaptability, high gasification efficiency, superior environmental protection performance and the like.

In the dry pulverized coal gasification technology operated in the current stage coal gasification market, common space furnaces and oriental furnaces adopt a direct chilling process, namely, crude synthesis gas generated by a combustion chamber is cooled by using a large amount of water, the sensible heat utilization rate is low, and the water consumption is high. The waste boiler process is represented by a shell furnace, namely, crude synthesis gas generated by a combustion chamber is firstly mixed with cold synthesis gas returned from the downstream for primary chilling and cooling, and then is further cooled by a convection waste boiler, high-temperature synthesis gas is primarily chilled and is cooled from 1350 ℃ to 850 ℃ so as to recover sensible heat through the convection waste boiler, the heat grade of the temperature interval is low, ash residues are not completely solidified at the inlet of the convection waste boiler, the blockage phenomenon easily occurs, and meanwhile, the equipment investment is high, the process flow is complex, and the later maintenance is difficult.

Disclosure of Invention

The application provides a waste boiler gasification device and a waste boiler gasification method for recovering waste heat of dry pulverized coal, the design of combining a radiation waste boiler and a cooling spray nozzle with a convection waste boiler is adopted, the radiation waste boiler is designed into a two-stage water-cooled wall structure, the heat recovery rate in the coal gasification process is increased, and the problems of complex process flow, difficult maintenance of a waste boiler system, substandard cooling and large investment of the existing waste boiler gasification furnace are solved; the problem that the convection waste boiler cannot be designed after the waste boiler is radiated in the existing gasification process is solved, the sensible heat of the high-temperature synthesis gas is recovered to the maximum extent, and the consumption of water can be greatly reduced.

The technical scheme adopted by the application is as follows:

a waste boiler gasification device for recovering waste heat of dry pulverized coal comprises a shell, wherein a combustion chamber and a radiation waste boiler which are mutually communicated are arranged in the shell from top to bottom, the top of the combustion chamber is provided with an overhead burner, 2N (N is more than or equal to 1) side burners are symmetrically arranged on two sides of the combustion chamber, and the bottom of the combustion chamber is provided with a slag hole; the radiation waste boiler is communicated with the lower end of the slag hole, a first-stage water-cooled wall and a second-stage water-cooled wall are respectively arranged in the radiation waste boiler from inside to outside in a spaced and parallel mode, a cooling spray head is installed below the first-stage water-cooled wall, and slag holes are formed in the radiation waste boiler and the bottom of the shell; and a synthesis gas outlet is formed in the side surface of the upper part of the radiation waste boiler, a gas transmission conduit is connected to the synthesis gas outlet, and the other end of the gas transmission conduit is communicated with the convection waste boiler.

Preferably, the upper end and the lower end of the combustion chamber are conical, the middle of the combustion chamber is cylindrical, an overhead burner is installed at the top end of the combustion chamber, two side burners are symmetrically installed at two sides of the combustion chamber, and the slag hole is formed in the conical hole at the lower end of the combustion chamber.

Preferably, the first stage waterwalls and the second stage waterwalls are both cylindrical waterwalls.

Preferably, the first-stage water-cooled wall is a combined structure of a cylindrical water-cooled wall and a fin water-cooled wall, wherein the fin water-cooled wall is arranged on the inner side of the cylindrical water-cooled wall of the first-stage water-cooled wall or between the first-stage water-cooled wall and the second-stage water-cooled wall, and the second-stage water-cooled wall is a cylindrical water-cooled wall.

Preferably, the fin water-cooling walls are uniformly distributed along the radial direction of the radiation waste boiler, and the number of the fin water-cooling walls is 4-24.

Preferably, the upper end of the first-stage water-cooled wall is connected with the upper end of the radiation waste boiler; the second-stage water-cooled wall is arranged on the outer side of the first-stage water-cooled wall and is parallel to the first-stage water-cooled wall, the distance between the inner wall of the second-stage water-cooled wall and the outer wall of the first-stage water-cooled wall is 0.2-2.0 m, the upper end of the second-stage water-cooled wall is flush with the lower end of the synthesis gas outlet, and the lower end of the second-stage water-cooled wall is compared with the lower end of the first-stage water-cooled wall and extends downwards for 0.2-2.0 m.

Preferably, the cooling spray head is installed on the lower portion of the shell, the cooling spray head is arranged at a position 0.1-2.0 meters below the first-stage water cooled wall, the cooling spray head is arranged into at least one layer, and 2-50 spray heads are uniformly distributed on each layer along the circumference of the lower end of the radiation waste boiler.

Preferably, the gas transmission conduit is horizontally arranged or obliquely arranged downwards, and a spiral coil water-cooled wall or a refractory material is arranged in the gas transmission conduit.

Preferably, the convection waste boiler adopts a structure of a third-stage cylindrical water-cooled wall and 3-20 groups of spiral coil water-cooled wall tubes, 2-10 circles of water-cooled walls are arranged on spiral tubes of each group of spiral coil water-cooled walls, and the spiral coil water-cooled walls are located inside the third-stage cylindrical water-cooled walls.

Another technical scheme adopted by the application is as follows:

according to the gasification method of the waste boiler gasification device for recovering the waste heat of the dry coal powder, the dry coal powder is sprayed into the combustion chamber through the overhead burner or the side burner, and is subjected to oxidation reaction with oxygen introduced through the overhead burner in the combustion chamber to generate crude synthesis gas and ash at the temperature of 1300-1700 ℃; the crude synthesis gas and the ash slag enter the radiation waste boiler through the slag hole, firstly pass through the first-stage water-cooling wall for primary heat recovery, reach the bottom of the radiation waste boiler from top to bottom along the first-stage water-cooling wall, and are subjected to chilling cooling by the cooling nozzle, wherein chilling media can adopt gas or chilling water, the chilled synthesis gas reaches a temperature between 300 ℃ and 1000 ℃, and the ash slag enters the bottom of the radiation waste boiler, is cooled to a temperature below 250 ℃ and is discharged through the slag discharge hole; the chilled synthesis gas enters a gap between the first-stage water-cooled wall and the second-stage water-cooled wall for secondary heat recovery; after the heat exchange is carried out for two times, the crude synthesis gas is cooled to be below 800 ℃, then enters the convection waste boiler through the gas transmission guide pipe, carries out the third heat recovery, and finally cools the crude synthesis gas to be 400 ℃ plus 200 ℃, thus finishing the recovery of the waste heat of the dry coal powder.

The technical scheme of the application has the following beneficial effects:

1. the invention relates to a waste boiler gasification device for recovering waste heat of dry coal powder, which adopts the design of a radiation waste boiler and a convection waste boiler, wherein the radiation waste boiler is designed into a two-stage water-cooled wall structure, the first-stage water-cooled wall is designed into a cylindrical water-cooled wall or a structure of a cylindrical water-cooled wall combined with a fin water-cooled wall, the second-stage water-cooled wall is a cylindrical water-cooled wall, the heat recovery rate in the coal gasification process is increased, a cooling nozzle is designed at the bottom of the radiation waste boiler to cool synthetic gas, the high-temperature synthetic gas passes through an annular gap between the first-stage water-cooled wall and the second-stage water-cooled wall, after twice heat exchange, the crude synthetic gas is cooled to be below 800 ℃, then the crude synthetic gas rises to the upper part of the radiation waste boiler and enters the convection waste boiler through a gas conveying conduit to carry out third heat recovery, and finally the crude synthetic gas is cooled to be between 200 ℃ and 400 ℃, and, the problems of complex process flow, difficult maintenance of a waste boiler system and large investment of the existing waste boiler gasification furnace are solved; the problem that the convection waste boiler cannot be designed after the waste boiler is radiated in the existing gasification process is solved, the sensible heat of the high-temperature synthesis gas is recovered to the maximum extent, and the consumption of water can be greatly reduced.

2. The invention reduces the temperature of the crude synthesis gas generated by the combustion chamber to 1300-1700 ℃ to 400 ℃, and finishes the high-grade heat recovery by three times of heat recovery, the recovered heat can be used as a heat source according to the actual production requirement, and the like, so that the heat utilization rate is high, and the production cost is saved.

3. The cooling spray heads are distributed in a full-coverage manner, so that the crude synthesis gas cooled by the first-stage water-cooled wall can be completely cooled, the phenomenon that fine ash mixed in the synthesis gas is brought into a gap between the first-stage water-cooled wall and the second-stage water-cooled wall to be bonded to block the channel due to overhigh temperature of the synthesis gas is reduced, and the shutdown phenomenon in the production process is reduced.

Drawings

In order to more clearly explain the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a waste boiler gasification device for recovering waste heat of dry pulverized coal according to the present invention;

FIG. 2 is a schematic structural diagram of the first stage water wall of the present invention using a combination of a cylindrical water wall and a fin water wall;

illustration of the drawings:

wherein, 1-top burner, 2-side burner, 3-combustion chamber, 4-slag hole, 5-radiation waste boiler, and 6-first stage

A water-cooled wall, a 7-shell, 8-a second-stage water-cooled wall, 9-a cooling spray head, 10-a slag discharge port, 11-a gas transmission conduit, 12-

Convection waste boiler, 61-cylindrical water-cooled wall, 62-fin water-cooled wall.

Detailed Description

Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following examples do not represent all embodiments consistent with the present application. But merely as exemplifications of systems and methods consistent with certain aspects of the application, as recited in the claims.

Referring to fig. 1, a schematic structural diagram of a waste boiler gasification device for recovering waste heat of dry pulverized coal is shown.

The waste boiler gasification device for recovering the waste heat of the dry pulverized coal comprises a shell 7, wherein a combustion chamber 3 and a radiation waste boiler 5 which are communicated with each other are arranged in the shell 7 from top to bottom, and the shell 7 is not directly contacted with high-temperature synthesis gas and is not heated under pressure; the top-mounted combustor 1 is installed at the top end of the combustion chamber 3, 2N (N is more than or equal to 1) side-mounted combustors 2 are symmetrically installed on two sides of the combustion chamber 3, a slag hole 4 is formed in the bottom of the combustion chamber 3, and a cooling wall is arranged on the inner wall of the combustion chamber 3; the radiation waste boiler 5 is communicated with the lower end of the slag hole 4, a primary water-cooled wall 6 and a secondary water-cooled wall 8 are respectively arranged in the radiation waste boiler 5 from inside to outside in a spaced and parallel mode, a cooling spray head 9 is installed below the primary water-cooled wall 6, and slag discharge holes 10 are formed in the bottom of the radiation waste boiler 5 and the bottom of the shell 7; and a synthesis gas outlet is formed in the side surface of the upper part of the radiation waste boiler 5, the synthesis gas outlet is connected with a gas transmission conduit 11, and the other end of the gas transmission conduit 11 is communicated with a convection waste boiler 12. This application adopts the design of radiation waste pot 5 with convection current waste pot 12, radiation waste pot 5 designs for two-stage water-cooling wall structure, and recovery high temperature synthesis gas sensible heat that can furthest, high-grade heat recovery rate is high.

The upper end and the lower end of the combustion chamber 3 are conical, the middle of the combustion chamber is cylindrical, an overhead burner 1 is installed at the top end of the combustion chamber 3, two side-mounted burners 2 are symmetrically installed on two sides of the combustion chamber 3, and a slag hole 4 is formed in the conical hole at the lower end of the combustion chamber 3. The combustor 3 can be provided with a plurality of side-arranged combustors 2 according to the production demand, and the flexibility is high.

The first-stage water-cooled wall 6 and the second-stage water-cooled wall 8 are both cylindrical water-cooled walls, and are simple in structure and convenient for later-stage maintenance and overhaul.

As shown in fig. 2, the first stage water-cooled wall 6 is a combined structure of a cylindrical water-cooled wall 61 and a fin water-cooled wall 62, wherein the fin water-cooled wall 62 is arranged inside the cylindrical water-cooled wall 61 of the first stage water-cooled wall 6 or between the first stage water-cooled wall 6 and the second stage water-cooled wall 8, and the second stage water-cooled wall 8 is a cylindrical water-cooled wall, which greatly increases the heat recovery rate in the coal gasification process.

The fin water-cooling walls 62 are uniformly distributed along the radial direction of the radiation waste boiler 5, the fin water-cooling walls 62 are arranged into 4-24 groups of water-cooling wall structures with the same length or different lengths, as shown in fig. 2, 16 groups of water-cooling wall structures with alternate lengths are adopted, and the design of the fin water-cooling walls 62 further increases the heat recovery rate of the crude synthesis gas.

The upper end of the first-stage water-cooled wall 6 is connected with the upper end of the radiation waste boiler 5; the second-stage water-cooled wall 8 is arranged on the outer side of the first-stage water-cooled wall 6 and is parallel to the first-stage water-cooled wall 6, the distance between the inner wall of the second-stage water-cooled wall 8 and the outer wall of the first-stage water-cooled wall 6 is 0.2-2.0 m, the upper end of the second-stage water-cooled wall 8 is flush with the lower end of the synthesis gas outlet, and the lower end of the second-stage water-cooled wall 8 is compared with the lower end of the first-stage water-cooled wall 6 and extends downwards for 0.2-2.0 m in. After entering a radiation waste boiler 5, the crude synthesis gas generated in the combustion chamber 3 firstly passes through the first-stage water-cooled wall 6 to be subjected to primary heat recovery, reaches the bottom along the first-stage water-cooled wall 6 from top to bottom and is cooled by the cooling nozzle, and the chilled synthesis gas enters a gap between the first-stage water-cooled wall 6 and the second-stage water-cooled wall 8 to be subjected to secondary heat recovery for twice heat exchange, so that the heat exchange efficiency is high, and the high-grade heat recovery rate is high.

The cooling spray head 9 is installed in the lower portion of the shell 7, the cooling spray head 9 is arranged at a position 0.1-2.0 meters below the first-stage water cooled wall 6, the cooling spray head 9 is arranged into at least one layer, and 2-50 spray heads are arranged on each layer and are evenly distributed along the circumference of the lower end of the radiation waste boiler 5. The cooling spray head 9 adopts full coverage type distribution, can make the process the crude synthesis gas after the cooling of first order water-cooling wall cools down completely, reduces to block up this passageway after leading into first order water-cooling wall and second level water-cooling wall clearance bonding because the fine ash that is mingled with in the synthesis gas is too high in the synthesis gas temperature, reduces the parking phenomenon in the production process.

Gas transmission pipe 11 sets up or sets up downwards to one side for the level, gas transmission pipe 11 is inside to be provided with spiral coil water-cooling wall or installation refractory material, because the entering in this embodiment the synthetic gas temperature of gas transmission pipe 11 is below 800 ℃, consequently refractory material select can to cut open the refractory material that withstands 800 ℃, can select according to the operating mode in the in-service use process, spiral coil water-cooling wall makes the synthetic gas pass through gas transmission pipe 11 gets into the in-process of convection current waste boiler 12, also can carry out heat recovery.

The convection waste boiler 12 is of a structure of a third-stage cylindrical water-cooled wall and 3-20 groups of spiral coil water-cooled wall tubes, 2-10 circles of water-cooled walls are arranged on spiral tubes of each group of spiral coil water-cooled walls, and the spiral coil water-cooled walls are located inside the third-stage cylindrical water-cooled walls. The synthesis gas enters the convection waste boiler 12 through the gas transmission guide pipe 11, the third heat recovery is carried out through the third-stage cylindrical water-cooling wall and 3-20 groups of spiral coil pipe water-cooling walls, finally the temperature of the crude synthesis gas is cooled to be between 200 and 400 ℃, the high-grade heat recovery can be realized, the heat utilization rate is high, the recovered heat can be used as a heat source according to actual production needs, and the like, so that the production cost is saved.

The gasification method of the waste boiler gasification device for recovering the waste heat of the dry coal powder comprises the following steps: dry coal powder is sprayed into the combustion chamber 3 through the overhead burner 1 or the side burner 2, and is subjected to oxidation reaction with oxygen introduced through the overhead burner 1 in the combustion chamber 3 to generate crude synthesis gas and ash at the temperature of 1300-1700 ℃; crude synthesis gas and ash enter the radiation waste boiler 5 through the slag hole 4, first pass through the primary water-cooled wall 6 for primary heat recovery, the crude synthesis gas and the ash reach the bottom of the radiation waste boiler 5 from top to bottom along the primary water-cooled wall 6, and are subjected to chilling cooling by the cooling nozzle 9, wherein chilling media can adopt gas or chilling water, the chilling gas usually adopts synthesis gas consisting of carbon dioxide or carbon monoxide and hydrogen, the consumption of the chilling media is related to the temperature of the synthesis gas at the bottom of the primary water-cooled wall 6, the chilled synthesis gas reaches 300-1000 ℃, the ash enters the bottom of the radiation waste boiler 5, is cooled to below 250 ℃, and is discharged through the slag discharge hole 10; the chilled synthesis gas enters a gap between the first-stage water-cooled wall 6 and the second-stage water-cooled wall 8 for secondary heat recovery; after the two heat exchanges, the crude synthesis gas is cooled to below 800 ℃, then enters the convection waste boiler 12 through the gas transmission conduit 11, and is subjected to third heat recovery, and finally the crude synthesis gas is cooled to 200-400 ℃, so that the dry coal powder waste heat recovery is completed. The invention has simple process flow, high heat recovery rate and convenient later maintenance, and is suitable for wide coal types.

This application adopts the design of radiation waste pot with convection current waste pot, and radiation waste pot internal design two-stage water-cooling wall structure, wherein first order water-cooling wall design is cylindric water-cooling wall or cylindric water-cooling wall combination fin water-cooling wall's structure, the second grade water-cooling wall is the cylindric water-cooling wall, has increased the heat recovery rate among the coal gasification process, after radiation waste pot bottom design cooling shower nozzle cooled down the synthetic gas, high temperature synthetic gas passes through the annular space between first order water-cooling wall and the second grade water-cooling wall, carries out twice heat transfer after, and the crude synthesis gas cools off to below 800 ℃, and then crude synthesis gas rises to radiation waste pot upper portion again and passes through the gas transmission pipe gets into the convection current waste pot, carries out heat recovery for the third time, finally cools off crude synthesis gas to between 200-, The waste boiler system is difficult to maintain and has large investment; the problem that the convection waste boiler cannot be designed after the waste boiler is radiated in the existing gasification process is solved, the sensible heat of the high-temperature synthesis gas is recovered to the maximum extent, and the consumption of water can be greatly reduced. The invention reduces the temperature of the crude synthesis gas generated by the combustion chamber to 1300-1700 ℃ to 400 ℃, and finishes the high-grade heat recovery by three times of heat recovery, the recovered heat can be used as a heat source according to the actual production requirement, and the like, so that the heat utilization rate is high, and the production cost is saved.

The embodiments provided in the present application are only a few examples of the general concept of the present application, and do not limit the scope of the present application. Any other embodiments extended according to the scheme of the present application without inventive efforts will be within the scope of protection of the present application for a person skilled in the art.