Organic solid waste pyrolysis gasification combustion system and pyrolysis gasification combustion method

Abstract

The invention provides an organic solid waste pyrolysis gasification combustion system and a pyrolysis gasification combustion method, and belongs to the technical field of combustion. The organic solid waste pyrolysis and gasification combustion system comprises a pyrolysis and gasification combustion furnace, wherein the furnace internally comprises an ash burning area, a pyrolysis and gasification area, a drying area and a secondary combustion area which are communicated in sequence; the drying area is provided with a first reciprocating grate, a first feeding hole is formed above the starting end of the first reciprocating grate, and the tail end of the first reciprocating grate is downwards communicated with the pyrolysis gasification area; the pyrolysis gasification area is provided with a second reciprocating fire grate, a second feeding port is formed above the starting end of the second reciprocating fire grate, the second reciprocating fire grate penetrates through the ash burning area, and the tail end of the second reciprocating fire grate is downwards communicated with a slag discharging channel; the secondary combustion area is an inverted-U-shaped channel, a third feeding port is formed in the starting end of the inverted-U-shaped channel, and a fourth feeding port is formed in the top of the inverted-U-shaped channel. The drying section, the pyrolysis gasification section and the ash burning section are combined; and a plurality of feeding holes are combined for feeding, so that the device is suitable for energy treatment of multi-source organic solid wastes with different heat values.

Description

Technical Field

[0001] The invention belongs to the technical field of combustion, and in particular relates to an organic solid waste pyrolysis gasification combustion system and a pyrolysis gasification combustion method. Background Art

[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] Organic solid waste comes from a wide range of sources, mainly including crop straw and vines, industrial organic waste residues, high-concentration organic waste liquid, landscaping waste, municipal sludge, domestic garbage, etc., and has the typical dual attributes of waste and resources. At present, distributed pyrolysis and centralized direct combustion are the main ways to utilize organic solid waste for energy. Direct combustion is suitable for many types of raw materials, but a higher excess air coefficient is required to ensure the full decomposition and combustion of organic matter, resulting in a large furnace volume and low treatment intensity per unit area. In addition, the amount of flue gas generated is large, and the concentration of pollutants such as nitrogen oxides is high, which is not conducive to the subsequent utilization of high-temperature flue gas heat and flue gas purification emissions, and the system investment and operating costs are high.

[0004] Pyrolysis is a process in which organic solid waste is heated to a certain temperature in an oxygen-free or low-oxygen environment, and the material molecules decompose. Guided by the target product, it can be divided into different pyrolysis processes such as pyrolysis gasification gas production, pyrolysis liquefaction oil production, and pyrolysis carbonization charcoal production. However, due to the limited supply of air / oxygen, organic matter is not completely decomposed, the conversion efficiency is low, and small molecular gas, solid coke, and tar-like macromolecular condensable liquids are inevitably produced at the same time. The system process is complex, with many types of by-products, and it is easy to cause secondary pollution. It is only suitable for the treatment of high-quality organic solid waste with low moisture content, high organic matter content, high calorific value, small particle size and uniformity. When the moisture content of the raw materials is high, the sources are different, the calorific value of the raw materials is low, and the calorific value deviation is large, it is difficult to control the reaction temperature, and it is easy to cause burn-through, burn-off, and fire extinguishing. It is easy to cause low pyrolysis reaction intensity and low thermal decomposition conversion efficiency, affecting the continuous operation stability, reliability and safety of the system. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide an organic solid waste pyrolysis gasification combustion system and a pyrolysis gasification combustion method, which establish the physical isolation of material drying, pyrolysis gasification and secondary combustion space and the organic coupling of the chemical reaction process in the whole process, so as to ensure the stable operation of the system and the thermal conversion efficiency.

[0006] In order to achieve the above object, the technical solution of the present invention is:

[0007] In a first aspect, an organic solid waste pyrolysis gasification combustion furnace includes an ash burning zone, a pyrolysis gasification zone, a drying zone and a secondary combustion zone which are connected in sequence;

[0008] The drying zone is provided with a first reciprocating grate, a first feed inlet is provided above the starting end of the first reciprocating grate, and the end is downwardly connected to the pyrolysis gasification zone;

[0009] The pyrolysis and gasification zone is provided with a second reciprocating grate, a second feed port is provided above the starting end of the second reciprocating grate, the second reciprocating grate passes through the ash burning zone, and the end is downwardly connected to the slag discharge channel;

[0010] The secondary combustion zone is an inverted U-shaped channel, a third feed inlet is arranged at the starting end of the inverted U-shaped channel, and a fourth feed inlet is arranged at the top of the inverted U-shaped channel.

[0011] In a second aspect, an organic solid waste pyrolysis gasification combustion system including the above-mentioned organic solid waste pyrolysis gasification combustion furnace includes: a feeding device, a slag discharge device, an air distribution device, a smoke exhaust device, and an operation monitoring and control device.

[0012] The feeding device comprises a silo, and the feeding device is connected to a first feeding port and a second feeding port, and is used for feeding materials into the feeding port;

[0013] The slag discharge device is connected to the slag discharge channel and is used for slag discharge;

[0014] The air distribution device is connected to the two-way ventilation ducts in the plurality of ash hoppers and the air supply port in the secondary combustion zone; the smoke exhaust device is connected to the smoke outlet and is used to process the smoke exhausted from the secondary combustion zone;

[0015] The operation monitoring and control device is connected to a plurality of temperature sensors in the pyrolysis gasification furnace.

[0016] In a third aspect, a pyrolysis and gasification combustion method using the above-mentioned organic solid waste pyrolysis and gasification combustion system comprises the following steps:

[0017] S1, the wet organic solid waste that has been dehydrated by filter pressing and homogenized is fed from the silo through the first feed port to the starting end of the first reciprocating grate in the pyrolysis gasification combustion furnace, where the water is evaporated under the action of dry air, and is fed from the end of the first reciprocating grate to the starting end of the second reciprocating grate, and the evaporated gas enters the secondary combustion zone through the first throat;

[0018] S2, the dry organic solid waste after homogenization and crushing enters the starting end of the second reciprocating grate in the pyrolysis gasification combustion furnace from the silo through the second feed inlet, and is naturally mixed with the material falling in S1, and is pyrolyzed and gasified under the action of pyrolysis gasification wind to produce mixed gas, residual carbon and solid ash;

[0019] The residual carbon and solid ash produced in S3 and S2 are transported to the ash burning zone by the second reciprocating grate, and are fully burned under the action of the ash burning wind to produce hot flue gas. The completely burned residue is transported to the slag discharge channel by the second reciprocating grate for discharge;

[0020] The hot flue gas generated in S4 and S3 and the mixed gas generated in S2 enter the drying area upward, flow in the opposite direction to the solid material for heat transfer, and enter the secondary combustion area through the first throat. Turbulence is formed under the action of the air supply port and the isolation wall in the secondary combustion area to maintain low-oxygen temperature-controlled combustion, and the flue gas is discharged from the flue gas outlet.

[0021] The beneficial effects of the present invention are:

[0022] 1. The raw materials of the present invention do not need to be finely crushed. A drying section is set in the furnace, and the heat released during the thermochemical conversion process of the materials can be directly and efficiently used to realize rapid drying of the materials in the furnace; the pyrolysis and gasification section and the ash burning section set subsequently adopt a combination of pyrolysis and gasification and burning according to the material characteristics of different reaction stages; in addition, multiple feed ports are used for joint feeding, which greatly expands the adaptability to different organic solid waste raw materials, and is particularly suitable for the energy disposal of organic solid waste from multiple sources and different calorific values. The system runs stably, and the generated tar, wood vinegar, etc. are directly coupled and burned in a high-temperature gaseous state, reducing secondary pollution.

[0023] 2. The present invention establishes physical isolation of material drying, pyrolysis and gasification and secondary combustion space and organic coupling of chemical reaction processes, which greatly improves the heat and mass transfer efficiency between materials and can fully burn the ash; the high-temperature fuel gas does not need to be cooled, and carries the gaseous tar directly in the secondary combustion zone to burn, making full use of the sensible heat of the fuel gas and the latent heat of the tar; the secondary combustion zone adopts a three-stage throat, three-time supplementary air distribution and inverted U-shaped structure design to ensure sufficient combustion, maximize the conversion of organic matter and energy release, and ensure the thermal conversion efficiency of the system.

[0024] 3. The present invention adopts a combined technology of pyrolysis and gasification coupled with low oxygen temperature control and low nitrogen combustion. Both pyrolysis and gasification and combustion are operated in a low oxygen or oxygen controlled environment. The temperature distribution in the reaction zone is more uniform, avoiding the violent oxidation combustion of biomass fuel, greatly reducing the generation of thermal nitrogen oxides, and highlighting the low nitrogen clean combustion characteristics; at the same time, the excess air coefficient is low, which greatly reduces the smoke exhaust volume, and also reduces the land occupation, investment and operating costs of subsequent flue gas heat utilization and purification treatment equipment.

[0025] 4. The drying section, pyrolysis gasification section, ash burning section and secondary combustion zone of the present invention can all adopt independent air distribution systems. At the same time, the area of ​​each reaction zone and the residence reaction time of the materials entering the furnace at each stage can be precisely controlled in a process, so that the system operating load can be adjusted within a larger range. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0027] Figure 1 This is a schematic diagram of the structure of the organic solid waste pyrolysis gasification combustion furnace in Example 1.

[0028] Among them, 1. the first feed port; 2. the first reciprocating grate; 3. the slag discharge channel; 4. the fourth isolation wall; 5. the second reciprocating grate; 6. the second feed port; 7. the material discharge channel; 8. the third isolation wall; 9. the first isolation wall; 10. the flue gas outlet; 11. the second isolation wall; 12. the third throat; 13. the second throat; 14. the explosion-proof port; 15. the fourth feed port; 16. the third feed port; 17. the first throat. DETAILED DESCRIPTION

[0029] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0030] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0031] Example 1

[0032] An organic solid waste pyrolysis gasification combustion furnace, such as Figure 1 As shown, the furnace includes an ash burning zone, a pyrolysis gasification zone, a drying zone and a secondary combustion zone which are connected in sequence;

[0033] The drying zone is provided with a first reciprocating grate 2, a first feed port 1 is provided above the starting end of the first reciprocating grate 2, and the end is downwardly connected to the pyrolysis gasification zone;

[0034] The pyrolysis and gasification zone is provided with a second reciprocating grate 5, and a second feed port 6 is provided above the starting end of the second reciprocating grate 5. The second reciprocating grate 5 passes through the ash burning zone, and the end thereof is downwardly connected to the slag discharge channel 3;

[0035] The secondary combustion zone is an inverted U-shaped channel. A third feed inlet 16 is provided at the starting end of the inverted U-shaped channel, and a fourth feed inlet 15 is provided at the top of the inverted U-shaped channel.

[0036] With such an arrangement, the drying section in the furnace can directly and efficiently utilize the heat released during the thermochemical conversion process of the material to achieve rapid drying of the material in the furnace; the pyrolysis and gasification section and the ash and slag combustion section use a combination of pyrolysis and gasification and combustion to carry out pyrolysis and combustion according to the material characteristics of different reaction stages; the produced tar, wood vinegar, etc. directly enter the secondary combustion zone with the pyrolysis gas in a high-temperature gaseous state for coupled combustion, thereby reducing the cooling and condensation of sticky substances such as tar to cause pipeline blockage or secondary pollution; coupled with the joint feeding of multiple feed ports, the adaptability to different organic solid waste raw materials is greatly expanded, and it is particularly suitable for the energy disposal of organic solid waste from multiple sources and different calorific values.

[0037] Specifically, Figure 1 As shown, the drying zone is an area surrounded by a furnace wall with a first feed port 1 on the left, a first reciprocating grate 2 at the bottom, a first isolation wall 9 on the upper right of the top, a first throat 17 on the upper left of the top, and the front and rear side furnace walls; the first isolation wall 9 is located on the upper right of the first reciprocating grate 2, and is arranged in an inclined shape with the left side higher and the right side lower, and is seamlessly connected to the right side furnace wall and the front and rear side furnace walls, and extends to the left to be connected to the bottom of the second isolation wall 11, and forms the first throat 17 with the left side furnace wall.

[0038] The first reciprocating grate 2 and the second reciprocating grate 5 are horizontally arranged mechanical reciprocating grates, which are composed of movable grate plates and fixed grate plates arranged alternately, and can transport materials in a set direction.

[0039] The first feed port 1 is used to add wet-based organic solid waste with a moisture content of 20% to 60%; preferably, the wet-based organic solid waste includes: pharmaceutical residues, wine lees, discarded edible fungus culture medium sticks, domestic garbage and other biomass organic solid waste raw materials.

[0040] The second feed port 6 is used to add dry organic solid waste with a moisture content of less than 20%. Preferably, the dry organic solid waste includes: tree bark and branches, crop straw and vines and other organic solid waste raw materials.

[0041] A drying air ash hopper is provided below the first reciprocating grate 2, which is used to introduce drying air into the first reciprocating grate 2, provide oxygen, and collect leaked slag; preferably, in order to achieve uniform air distribution, the drying air ash hopper is provided with a plurality of independently segmented drying air chambers, and a two-way ventilation duct is provided in each drying air chamber;

[0042] Specifically, Figure 1 As shown, the two-way ventilation ducts are arranged along the front and rear side furnace walls.

[0043] The end of the first reciprocating grate 2 is downwardly connected to a vertical material dropping channel 7, and the lower part of the material dropping channel 7 is connected to the starting end of the second reciprocating grate 5;

[0044] Specifically, Figure 1As shown, the right end of the first reciprocating grate 2 is connected to the third isolation wall 8, the third isolation wall 8 is seamlessly connected to the front and rear side furnace walls, and forms a drying material dropping channel 7 and a pyrolysis gasification zone flue gas rising channel between the third isolation wall 8 and the right side furnace wall.

[0045] A pyrolysis gasification air ash hopper is provided below the second reciprocating grate 5 of the pyrolysis gasification zone, which is used to introduce pyrolysis gasification air into the second reciprocating grate 5 of the pyrolysis gasification zone, provide oxygen, and collect leaked slag; preferably, in order to achieve uniform air distribution, the pyrolysis gasification air ash hopper is provided with a plurality of independently segmented pyrolysis gasification air chambers, and a two-way ventilation duct is provided in each pyrolysis gasification air chamber;

[0046] Specifically, Figure 1 As shown, the pyrolysis and gasification zone is: an area surrounded by a furnace wall with a second feed port 6 on the right, a second reciprocating grate 5 at the bottom, a top left upper furnace wall, a top right upper material dropping channel 7 and the front and rear side furnace walls; the top left upper furnace wall of the pyrolysis and gasification zone is located directly above the second reciprocating grate 5, and is arranged in an inclined shape with the left side low and the right side high, and is connected to the top furnace wall of the ash burning zone on the left side, is connected to the third isolation wall 8 on the right side, and is seamlessly connected to the front and rear side furnace walls.

[0047] An ash burning air hopper is provided below the second reciprocating grate 5 in the ash burning zone. The ash burning air hopper is used to introduce ash burning air into the second reciprocating grate in the ash burning zone, provide oxygen, and collect leaked slag.

[0048] Specifically, Figure 1 As shown, the ash burning zone is located on the left side of the pyrolysis gasification zone, and is an area surrounded by the second reciprocating grate 5 at the bottom, the top furnace wall, and the front and rear side furnace walls; the top furnace wall of the ash burning zone is arranged horizontally, and the left side is connected to the left furnace wall, and the right side is connected to the upper left furnace wall at the top of the pyrolysis gasification zone; the left end of the second reciprocating grate 5 is connected to the fourth isolation wall 4, and the fourth isolation wall 4 is seamlessly connected to the front and rear side furnace walls, and forms a slag discharge channel 3 between the left furnace wall.

[0049] The starting end of the secondary combustion zone is located at the top of the drying zone, and a first throat 17 is provided at the starting end of the secondary combustion zone; a second isolation wall 11 with an opening at the upper end is provided in the middle of the secondary combustion zone, so that the secondary combustion zone forms an inverted U-shaped channel; the upper end opening of the second isolation wall 11 forms a second throat 13; and a third throat 12 is provided in the downward channel of the inverted U-shaped channel.

[0050] Specifically, Figure 1 As shown, the secondary combustion zone is located at the top of the pyrolysis gasification furnace, and is an area surrounded by the first throat 17 structure, the first isolation wall 9, the front, back, left, right and top furnace walls.

[0051] A first air supply port is provided at the first throat 17, a second air supply port is provided at the second throat 13, and a third air supply port is provided at the third throat 12; each group of air supply ports is provided with air distribution ports that are staggered in opposite directions; through multi-stage air distribution and distributed combustion, the geometric size of the flame is increased, the combustion process is delayed, the temperature field is more uniform, and violent oxidative combustion is avoided, so that the secondary combustion zone always maintains a low-oxygen temperature-controlled combustion environment, greatly reducing the generation of thermal nitrogen oxides, and realizing low-oxygen temperature-controlled and low-nitrogen combustion.

[0052] In the inverted U-shaped channel, a third feed port 16 is provided downstream of the first air supply port, and a fourth feed port 15 is provided upstream of the second air supply port; a diesel burner is provided at the third feed port; and the fourth feed port is used for injecting high-concentration organic waste liquid.

[0053] Specifically, Figure 1 As shown, the left secondary combustion zone is provided with a third feed inlet 16 on the left furnace wall near the first throat 17, and a fourth feed inlet is provided on the top furnace wall.

[0054] In the inverted U-shaped channel, an explosion-proof opening is arranged at the top of the descending channel; in the inverted U-shaped channel, a smoke outlet 10 is arranged at the end of the descending channel.

[0055] Specifically, Figure 1 As shown, an explosion-proof opening 14 is provided on the top furnace wall of the right secondary combustion zone, and a smoke outlet 10 is provided on the right furnace wall below the third throat 12.

[0056] Each ash hopper can be used to clean the slag leaking from the grate when the system is shut down for maintenance.

[0057] Example 2

[0058] An organic solid waste pyrolysis gasification combustion system including the above-mentioned organic solid waste pyrolysis gasification combustion furnace comprises: a feeding device, a slag discharge device, an air distribution device, a smoke exhaust device, and an operation monitoring and control device.

[0059] The feeding device comprises a silo, the feeding device is connected to the first feeding port 1 and the second feeding port 6, and is used to feed materials into the feeding ports;

[0060] The slag discharge device is connected to the slag discharge channel 3 and is used for slag discharge;

[0061] The air distribution device is connected to the two-way ventilation ducts in the multiple ash hoppers and the air supply ports in the secondary combustion zone; the smoke exhaust device is connected to the smoke outlet and is used to process the smoke exhausted from the secondary combustion zone;

[0062] The operation monitoring and control device is connected to a plurality of temperature and gas pressure sensors in the pyrolysis gasification furnace.

[0063] The pyrolysis and gasification combustion method using the above-mentioned organic solid waste pyrolysis and gasification combustion system comprises the following steps:

[0064] S1, the wet organic solid waste that has been dehydrated by filter pressing and homogenized is fed from the silo through the first feed port 1 to the starting end of the first reciprocating grate 2 in the pyrolysis gasification combustion furnace, where the water is evaporated under the action of dry air, and is fed from the end of the first reciprocating grate 2 to the starting end of the second reciprocating grate 5, and the evaporated gas enters the secondary combustion zone through the first throat 17;

[0065] S2, the dry organic solid waste after homogenization and crushing enters the starting end of the second reciprocating grate 5 in the pyrolysis gasification combustion furnace from the silo through the second feed port 6, and is naturally mixed with the falling materials in S1, and is pyrolyzed and gasified under the action of pyrolysis gasification wind to produce mixed gas, residual carbon and solid ash;

[0066] The residual carbon and solid ash produced in S3 and S2 are transported to the ash burning zone by the second reciprocating grate 5, and are fully burned under the action of the ash burning wind to produce hot flue gas. The completely burned residue is transported to the slag discharge channel 3 by the second reciprocating grate 5 for discharge;

[0067] The hot flue gas generated in S4 and S3 and the mixed gas generated in S2 enter the drying zone upward, flow in the opposite direction to the solid material for heat transfer, and enter the secondary combustion zone through the first throat 17. Turbulence is formed under the action of the air supply port and the isolation wall in the secondary combustion zone, maintaining low-oxygen temperature-controlled combustion, and the flue gas is discharged from the flue gas outlet 10.

[0068] By adopting the combined technology of pyrolysis and gasification coupled with low-oxygen temperature-controlled and low-nitrogen combustion, a multi-stage air distribution system (multiple air inlets) is set up in the device, and a distributed combustion method is adopted. Both pyrolysis and gasification and combustion are operated in a low-oxygen or oxygen-controlled environment, which delays the combustion process, makes the temperature distribution in the reaction zone more uniform, avoids the violent oxidation combustion of biomass fuel, and especially keeps the secondary combustion zone in a low-oxygen temperature-controlled combustion state, greatly reducing the generation of thermal nitrogen oxides, realizing low-oxygen temperature-controlled and low-nitrogen combustion, and further highlighting the low-nitrogen clean combustion characteristics.

[0069] In S1, the raw materials fed into the furnace through the first feed port 1 do not need to be finely crushed, and can be fed into the furnace with a particle size of ≤50 mm, a length of ≤200 mm, and a moisture content of ≤60%.

[0070] In S1, the material movement speed and the residence time in the drying section are adjusted by the driving frequency of the movable grate of the first reciprocating grate 2; the moisture content of the wet-based organic solid waste after drying in the drying area is greatly reduced, and the material properties are more uniform, which is conducive to the subsequent pyrolysis and gasification reaction and the full combustion of organic matter in the ash, so as to maintain the continuous and stable operation of the system.

[0071] Preferably, the moisture content of the material entering the furnace from the first feed inlet 1 is less than 50%, the particle size is less than 10 mm, the drying air is hot air preheated to 150-200° C. by high-temperature flue gas, the material stays in the drying zone for 10-40 minutes, and the moisture content of the dried material is less than 35%.

[0072] In S2, the material is loosened and moved forward under the drive of the second reciprocating grate 5, and a series of incomplete combustion thermochemical reactions such as pyrolysis and gasification are carried out in stages under the action of the pyrolysis and gasification wind, generating a mixed gas containing carbon monoxide, hydrogen, methane, carbon dioxide, unsaturated hydrocarbon small molecules and tar macromolecules, as well as solid ash containing some incompletely reacted residual carbon and inorganic components.

[0073] In S3, the solid ash enters the ash burning zone under the push of the second reciprocating grate 5, and the ash residual carbon is burned under the action of the burning air supply, so as to promote the full decomposition and energy release of the organic components in the solid residual carbon, thereby achieving the maximum reduction of organic solid waste.

[0074] In S3, the hot flue gas generated by the burning of the ash moves in the opposite direction to the material on the second reciprocating grate 5, providing continuous energy support and stable reaction temperature guarantee for the pyrolysis and gasification reaction of the material;

[0075] The hot flue gas from the burning of ash and the mixed gas with sensible heat generated by pyrolysis and gasification move upward through the material dropping channel 7, forming a counter-flow with the falling dried material, which greatly promotes the heat and mass transfer between them, realizes further drying and preheating of the material, ensures that the falling material is heated evenly and fully, and provides good material conditions for the thermochemical reaction of the material in the pyrolysis and gasification zone.

[0076] In S4, under the joint action of the three throat structures in the secondary combustion zone, the three air supply ports and the second isolation wall 11, the gas entering the secondary combustion zone is fully mixed with efficient turbulence, which prolongs the residence of the flue gas, increases the combustion time, improves the combustion efficiency, and ensures the complete decomposition and combustion of the gas components; at the same time, through multi-stage air distribution, segmented pyrolysis gasification and distributed combustion, the flame geometry is increased, the combustion process is delayed, the temperature field is more uniform, and violent oxidative combustion is avoided, so that the secondary combustion zone always maintains a low-oxygen temperature-controlled combustion environment, greatly reducing the generation of thermal nitrogen oxides and achieving clean combustion; in this process, the high-temperature flue gas in the secondary combustion zone can also be transmitted through the first isolation wall 9 to the high-temperature radiation heat supply in the drying zone to supplement the energy used for drying materials in the drying zone.

[0077] Finally, the high-temperature flue gas after sufficient decomposition and combustion is discharged from the flue gas outlet 10 for high-temperature waste heat utilization and purification.

[0078] The total air supply volume is 105% to 110% of the theoretical air volume for complete combustion of the materials entering the furnace; preferably, the air supply volume ratio of the drying air, pyrolysis gasification air, combustion air, the first air supply port, the second air supply port and the third air supply port is drying air volume: pyrolysis gasification air volume: combustion air volume: first air supply volume: second air supply volume: third air supply volume = (0.15-0.25): (0.2-0.3): (0.1-0.15): (0.25-0.35): (0.1-0.15): (0.05-0.1).

[0079] Example 3

[0080] The method for regulating the temperature in the furnace of the organic solid waste pyrolysis gasification combustion system provided in Example 2 is as follows:

[0081] When the calorific value of the wet organic solid waste entering the furnace through the first feed inlet 1 is low, the calorific value or feed amount of the dry organic solid waste entering the furnace is adjusted through the second feed inlet 6 to maintain the temperature of the secondary combustion zone above 850°C, and the temperature is measured by a sensor in the furnace connected to the operation monitoring and control device;

[0082] When the temperature of the secondary combustion zone exceeds 1000°C, the fourth feed port 15 is opened to coordinately dispose of the high-concentration organic waste liquid; when the temperature of the secondary combustion zone is lower than 900°C, the fourth feed port is closed;

[0083] When the system starts and stops the furnace or the temperature in the secondary combustion zone drops rapidly, the diesel burner at the third feed inlet 16 is turned on to add heat to the system and stabilize the temperature in the secondary combustion zone at above 850°C.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An organic solid waste pyrolysis gasification combustion furnace, characterized in that: The furnace includes an ash burning zone, a pyrolysis gasification zone, a drying zone and a secondary combustion zone which are connected in sequence; The drying zone is provided with a first reciprocating grate, a first feed inlet is provided above the starting end of the first reciprocating grate, and the end is downwardly connected to the pyrolysis gasification zone; The pyrolysis and gasification zone is provided with a second reciprocating grate, a second feed port is provided above the starting end of the second reciprocating grate, the second reciprocating grate passes through the ash burning zone, and the end is downwardly connected to the slag discharge channel; The secondary combustion zone is an inverted U-shaped channel, a third feed inlet is arranged at the starting end of the inverted U-shaped channel, and a fourth feed inlet is arranged at the top of the inverted U-shaped channel.

2. The organic solid waste pyrolysis gasification combustion furnace according to claim 1, characterized in that: A drying air ash hopper is provided below the first reciprocating grate, for introducing drying air into the first reciprocating grate and collecting leaked slag; preferably, the drying air ash hopper is provided with a plurality of independently segmented drying air chambers, each of which is provided with a two-way ventilation duct; Optionally, the end of the first reciprocating grate is downwardly connected to a vertical material dropping channel, and the material dropping channel is downwardly connected to the starting end of the second reciprocating grate.

3. The organic solid waste pyrolysis gasification combustion furnace according to claim 1, characterized in that: A pyrolysis gasification air ash hopper is provided below the second reciprocating grate in the pyrolysis gasification zone, which is used to introduce pyrolysis gasification air into the second reciprocating grate in the pyrolysis gasification zone and collect leaked slag; preferably, the pyrolysis gasification air ash hopper is provided with a plurality of independently segmented pyrolysis gasification air chambers, and a two-way ventilation duct is provided in each pyrolysis gasification air chamber; Optionally, an ash burning air hopper is provided below the second reciprocating grate in the ash burning zone, and the ash burning air hopper is used to introduce ash burning air into the second reciprocating grate in the ash burning zone and collect leaked slag.

4. The organic solid waste pyrolysis gasification combustion furnace according to claim 1, characterized in that: The starting end of the secondary combustion zone is located at the top of the drying zone, and a first throat is arranged at the starting end of the secondary combustion zone; a second isolation wall with an upper end opening is arranged in the middle of the secondary combustion zone, so that the secondary combustion zone forms an inverted U-shaped channel; the upper end opening of the second isolation wall forms a second throat; and a third throat is arranged at the starting end of the descending channel of the inverted U-shaped channel.

5. The organic solid waste pyrolysis gasification combustion furnace according to claim 4, characterized in that: A first air supply port is arranged at the first throat position, a second air supply port is arranged at the second throat position, and a third air supply port is arranged at the third throat position; each group of air supply ports is provided with air distribution ports arranged in a staggered manner opposite to each other.

6. The organic solid waste pyrolysis gasification combustion furnace according to claim 4, characterized in that: In the inverted U-shaped channel, a third feed inlet is provided at a position downstream of the first air supply inlet, and a fourth feed inlet is provided at a position upstream of the second air supply inlet; In the inverted U-shaped channel, an explosion-proof opening is provided at the top of the descending channel; optionally, in the inverted U-shaped channel, a smoke outlet is provided at the end of the descending channel; Optionally, a diesel burner is provided at the third feed port; and the fourth feed port is used for injecting high-concentration organic waste liquid.

7. An organic solid waste pyrolysis gasification combustion system comprising the organic solid waste pyrolysis gasification combustion furnace according to any one of claims 1 to 6, characterized in that: include: Feeding device, slag discharge device, air distribution device, smoke exhaust device, operation monitoring and control device; The feeding device comprises a silo, and the feeding device is connected to a first feeding port and a second feeding port, and is used for feeding materials into the feeding port; The slag discharge device is connected to the slag discharge channel and is used for slag discharge; The air distribution device is connected to the two-way ventilation ducts in the plurality of ash hoppers and the air supply ports in the secondary combustion zone; The smoke exhaust device is connected to the smoke outlet and is used to process the smoke exhausted from the secondary combustion zone; The row monitoring and control device is connected to multiple temperature and gas pressure sensors in the pyrolysis gasification furnace.

8. A pyrolysis and gasification combustion method using the organic solid waste pyrolysis and gasification combustion furnace according to any one of claims 1 to 6 and / or the organic solid waste pyrolysis and gasification combustion system according to claim 7, characterized in that: The following steps are involved: S1, the wet organic solid waste that has been dehydrated by filter pressing and homogenized is fed from the silo through the first feed port to the starting end of the first reciprocating grate in the pyrolysis gasification combustion furnace, where the water is evaporated under the action of dry air, and is fed from the end of the first reciprocating grate to the starting end of the second reciprocating grate, and the evaporated gas enters the secondary combustion zone through the first throat; S2, the dry organic solid waste after homogenization and crushing enters the starting end of the second reciprocating grate in the pyrolysis gasification combustion furnace from the silo through the second feed port 6, and is naturally mixed with the falling materials in S1, and is pyrolyzed and gasified under the action of pyrolysis gasification wind to produce mixed gas, residual carbon and solid ash; The residual carbon and solid ash produced in S3 and S2 are transported to the ash burning zone by the second reciprocating grate, and are fully burned under the action of the ash burning wind to produce hot flue gas. The completely burned residue is transported to the slag discharge channel by the second reciprocating grate for discharge; The hot flue gas generated in S4 and S3 and the mixed gas generated in S2 enter the drying area upward, flow in the opposite direction to the solid material for heat transfer, and enter the secondary combustion area through the first throat. Turbulence is formed under the action of the air supply port and the isolation wall in the secondary combustion area to maintain low-oxygen temperature-controlled combustion, and the flue gas is discharged from the flue gas outlet.

9. The pyrolysis gasification combustion method according to claim 8, characterized in that: The raw materials of the materials fed into the furnace through the first feed port do not need to be finely crushed, and the particle size is ≤50mm, the length is ≤200mm, and the moisture content is ≤60%; preferably, the moisture content of the materials fed into the furnace through the first feed port 1 is <50%, and the particle size is <10mm; Optionally, the drying air supply is hot air preheated to 150-200°C by high-temperature flue gas, the material stays in the drying area for 10-40 minutes, and the moisture content of the dried material is less than 35%; Optionally, the total air volume is 105% to 110% of the theoretical air volume for complete combustion of the materials entering the furnace; Optionally, the ratio of the air volume of each part of the drying air, pyrolysis gasification air, combustion air, first air supply port, second air supply port and third air supply port is drying air volume: pyrolysis gasification air volume: combustion air volume: first air supply volume: second air supply volume: third air supply volume = (0.15-0.25): (0.2-0.3): (0.1-0.15): (0.25-0.35): (0.1-0.15): (0.05-0.1).

10. The pyrolysis gasification combustion method according to claim 8, characterized in that: When the calorific value of the wet organic solid waste entering the furnace through the first feed inlet is low, the calorific value or feed amount of the dry organic solid waste entering the furnace is adjusted through the second feed inlet to maintain the temperature of the secondary combustion zone above 850°C, and the temperature is measured by a sensor in the furnace connected to the operation monitoring and control device; Optionally, when the temperature of the secondary combustion zone exceeds 1000°C, the fourth feed port is opened to collaboratively dispose of the high-concentration organic waste liquid until the temperature of the secondary combustion zone is lower than 900°C, and then the fourth feed port is closed; Optionally, when the system starts and stops the furnace or the temperature in the secondary combustion zone drops rapidly or other abnormal situations occur, the diesel burner at the third feed inlet is turned on to add heat to the system and stabilize the temperature in the secondary combustion zone at above 850°C.

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