Alternating pyrolysis gasification device and method

Abstract

The present invention discloses an alternating pyrolysis and gasification device and method. The device includes a rotating tank body, a lifting blade, a rotating shaft, a crushing blade, etc. Organic solid waste undergoes pyrolysis in a rotating tank body with a double cone; the spiral lifting blade fixed to the wall of the rotating tank can lift the material by rotation, and as the diameter of the lifting blade decreases, the material is continuously pushed to the middle of the tank body and falls, which can achieve full circulation of the material and make it evenly heated; and the counter-rotating crushing blade can peel off the residual carbon on the surface of the material by shearing and crushing, thereby enhancing heat transfer; after the pyrolysis is completed, the residual carbon can be gasified with a gasifying agent and converted into inorganic waste slag for direct landfill; the pyrolysis gas and gasification gas generated by the device can be used for combustion energy supply and fuel cell power generation, so as to achieve self-sustaining operation of the device. The above-mentioned device can effectively improve resource utilization through continuous alternating operation of pyrolysis and gasification processes, curb the generation of harmful substances such as dioxins, and achieve harmless disposal and high-value utilization of organic solid waste.

Description

Technical Field

[0001] The present invention belongs to the technical field of harmless treatment of organic solid waste, and specifically relates to an alternating pyrolysis and gasification device. The present invention also provides a method for realizing the alternating pyrolysis and gasification. Background Art

[0002] Organic solid waste (ORSG) refers to solid and semi-solid organic items and materials generated in production, life and other activities that have lost their original utilization value or have not lost their utilization value but have been discarded or abandoned; organic solid waste mainly includes agricultural and forestry waste, garbage, sludge, industrial waste, waste plastics, etc.; the amount of organic solid waste generated is also increasing, and the treatment of organic solid waste has received increasing attention.

[0003] Conventional methods for treating organic solid waste include landfill and incineration, and landfill is still the main treatment method. Although landfill is simple to operate and widely adaptable, it takes a long time to treat, pollutes the soil and groundwater, causes secondary pollution, and has a huge negative impact on the surrounding environment; high-temperature incineration is low-cost, high-efficiency, and can treat a large amount of waste. It can quickly reduce weight and obtain usable heat energy, but it will produce pollutants such as dioxins during the combustion process.

[0004] Pyrolysis and gasification are highly efficient technologies for treating organic solid waste. The use of pyrolysis technology to treat organic solid waste also has the advantages of high treatment efficiency, wide adaptability, and short treatment cycle. In particular, since pyrolysis is an anaerobic process, it can dechlorinate harmlessly, that is, under low temperature conditions, its reducing atmosphere can effectively prevent the conversion of chlorine-containing components into harmful substances such as dioxins, avoiding secondary pollution. In addition, the pyrolysis process can be used to prepare high-value chemicals or fuels, and since pyrolytic carbon is not easy to burn and has low utilization efficiency, it can be combined with gasification technology to further produce gasification gas for fuel cell power generation, thereby improving the resource utilization rate of organic solid waste. Therefore, pyrolysis gasification technology has higher practical value than high-temperature incineration treatment technology.

[0005] However, some organic solid wastes are widely distributed, not concentrated, have small single output, and cannot be stored for a long time. Therefore, it is necessary to develop corresponding small-scale, distributed, and mobile disposal equipment that can be transported by vehicle.

[0006] Conventional pyrolysis and gasification devices adopt a dual-chamber structure, using two pyrolysis chambers and gasification chambers connected in series to perform pyrolysis of raw materials and gasification of residual carbon / coke / semi-coke, respectively. Chinese patent CN 201510160008.9 discloses a scheme of vertically coaxial arrangement of a down-flowing bed rapid pyrolyzer and a bubbling bed gasifier, in which the semi-coke generated by the upper pyrolyzer falls directly into the gasifier below by gravity through a separator to react with the gasifying agent, but this pyrolysis and gasification device arranged continuously up and down requires a higher spatial position. The pyrolysis and gasification device disclosed in Chinese patent CN 201410437582.X is two separate fluidized bed reaction chambers, which perform pyrolysis and gasification processes respectively, and also require a larger spatial position, making it difficult to miniaturize. For a single-chamber fluidized bed reactor, although it can be operated intermittently and the pyrolysis and gasification processes can be realized in stages to save reactor space, it still requires complex auxiliary equipment such as air distribution and separation, which is not suitable for miniaturization. However, single-chamber fixed bed and rotary reactors are difficult to overcome the problems of uneven heating of materials and difficulty in penetrating energy into the materials. Therefore, it is urgent to design a miniaturized mobile reaction device that can efficiently exchange heat for organic solid waste and organically combine pyrolysis and gasification processes. Summary of the invention

[0007] The present invention mainly solves the technical problem that the existing pyrolysis gasification devices have the disadvantages of uneven heat transfer, low heat exchange efficiency, difficulty in miniaturization, etc., and cannot effectively achieve efficient disposal of organic solid waste. An organic solid waste alternating pyrolysis gasification device and method are provided.

[0008] In order to solve the above technical problems, the present invention provides an organic solid waste alternating pyrolysis gasification device, comprising an external shell, wherein the external shell is provided with a feed inlet, a discharge port, a gasifying agent inlet, a gas outlet, a smoke inlet and a smoke outlet;

[0009] A rotating tank body, the rotating tank body is rotatably installed in the outer shell and is arranged to form a flue between the rotating tank body and the outer shell, the rotating axis of the rotating tank body is inclined relative to the vertical direction, and a spiral material lifting blade extending around the rotating axis is connected to the inner wall surface; wherein the feed port, the discharge port, the gasifying agent inlet and the gas outlet are all connected to the inner cavity of the rotating tank body, and the smoke inlet and the smoke outlet are respectively connected to the flue; and,

[0010] A stirring shaft, the stirring shaft extends along the rotation axis of the rotating tank body and is connected with crushing blades, the crushing blades are composed of a plurality of stirring rods or plate-type stirring paddles with slots; the crushing blades are distributed in the gaps of the lifting blades and the extension length is smaller than the inner diameter of the corresponding lifting blade on the rotating plane, so as to allow the stirring shaft to be driven to rotate in the opposite direction relative to the rotating tank body.

[0011] Preferably, the rotating tank body has a double-conical cylinder with conical bottoms connected to each other, and the upper and lower ends of the double-conical cylinder are respectively supported by the external shell through bearings; the upper and lower ends of the stirring shaft are both supported by the external shell through bearings.

[0012] Preferably, the alternating pyrolysis gasification device also includes a driving system that is transmission-connected to the stirring shaft and a transmission system that is transmission-connected between the rotating tank body and the stirring shaft. The driving system can drive the stirring shaft to rotate, and drive the rotating tank body to rotate in the opposite direction relative to the stirring shaft through the transmission system, so that the lifting blades transport at least part of the solid material in the rotating tank body upward.

[0013] Preferably, the feed port is connected to the upper end of the rotating tank body, and the gas outlet is connected to the inner cavity of the rotating tank body through the feed port; and a plurality of gasifying agent inlets connected to the lower end of the rotating tank body are provided on the external shell.

[0014] Preferably, a discharge gate is provided on the connecting interface between the rotating tank body and the discharge port, and the discharge gate is configured to be able to close the discharge port, and the discharge port is connected to a solid collecting device.

[0015] Preferably, the gas outlet is divided into two paths, one path is connected to the adsorption device via a pyrolysis gas pipeline, and the other path is connected to the fuel cell system via a gasification gas pipeline; the dechlorination pyrolysis gas outlet of the adsorption device is connected to the gas inlet of the condensation device, the gas outlet of the condensation device is connected to the burner, the flue gas outlet of the burner is connected to the flue gas inlet of the external shell, and the flue gas outlet of the external shell is connected to the purification device.

[0016] Preferably, heat exchange fins are arranged on the outer side of the rotating tank.

[0017] Preferably, the distance between the upper end of the lifting blade and the feed port is not less than 100 mm, and the angle between the rotation axis of the rotating tank body and the horizontal plane is 30-60°.

[0018] The present invention also provides a method for using the above-mentioned organic solid waste alternating pyrolysis and gasification device, wherein the pyrolysis and gasification stages are intermittently and alternately operated, the organic solid waste is pyrolyzed in the pyrolysis stage to produce pyrolysis gas and pyrolysis carbon residue, and the pyrolysis carbon residue is further gasified in the gasification stage to produce gasification gas and inorganic waste residue, comprising the following steps:

[0019] S1. The alternating pyrolysis gasification device starts to operate, driving the stirring shaft and the rotating tank to rotate in opposite directions;

[0020] S2. The high-temperature flue gas is introduced into the flue through the flue gas inlet to preheat the rotating tank;

[0021] S3. The quantitative organic solid waste raw material is fed into the rotating tank through the feed port, heated, dried to remove part of the water, and gradually pyrolyzed;

[0022] S4. The rotating tank body drives the lifting blades to rotate; under the push of the lifting blades, at least part of the organic solid waste at the bottom of the tank is gradually lifted to the top of the tank body along the inner wall of the tank, and then the organic solid waste falls from the middle of the rotating tank body back to the bottom; at the same time, the stirring shaft drives the crushing blades to rotate in the opposite direction to the rotation of the pyrolysis tank, stirring and crushing the organic solid waste when it rises or falls, so that the organic solid waste is heated evenly and the residual carbon on the surface that is fully pyrolyzed is continuously peeled off; under the combined action of the stirring and crushing of the lifting blades and the crushing blades, the organic solid waste continuously repeats the cycle process from the bottom to the top near the wall of the rotating tank body, and returns from the top to the bottom from the inside of the rotating tank body, continuously decomposes under heat to produce pyrolysis gas, and the volume gradually decreases until the pyrolysis is complete and only the pyrolysis residual carbon remains in the rotating tank body;

[0023] S5. By adjusting the flue gas flow and distribution, the temperature of the rotating tank is further increased to start the gasification process of the residual carbon;

[0024] S6. The gasifying agent is continuously introduced from the gasifying agent inlet, and the pyrolysis carbon residue is fluidized and fully mixed with the gasifying agent by the dual stirring of the lifting blade and the crushing blade; the pyrolysis carbon residue is gasified under the action of the gasifying agent to produce gasification gas; when the gasification efficiency reaches the peak value, the temperature of the rotating tank body begins to decrease; as the pyrolysis carbon residue is completely gasified, only inorganic waste residue remains in the rotating tank body;

[0025] S7. The inorganic waste is discharged and collected through the discharge port, and the temperature of the rotating tank body continues to decrease, ready to feed again;

[0026] S8. The pyrolysis gas produced by the pyrolysis of organic solid waste is dechlorinated, condensed, and the liquid products are collected, while the non-condensable gas is burned in the burner to provide power and high-temperature flue gas for the device; the gasification gas produced by the gasification of pyrolysis residual carbon is used to generate electricity in the fuel cell to provide electrical energy for the device; the low-temperature flue gas discharged from the flue is purified in the purification device and then discharged.

[0027] Preferably, in step S6, the gasifying agent introduced is water vapor and oxygen, and in steps S3 to S6, the rotating tank body cyclically fluctuates between 300 and 1200°C, wherein the pyrolysis stage in steps S3 and S4 meets 300 to 600°C, and the gasification stage in steps S5 and S6 meets 800 to 1200°C.

[0028] The core of the organic solid waste alternating pyrolysis and gasification device described in the technical solution of the present invention is a lifting blade whose diameter changes with the inner wall of the double-conical rotating tank, a crushing blade arranged on a counter-rotating stirring shaft, and an integrated alternating pyrolysis and gasification reactor. The organic solid waste first enters the rotating tank and gradually undergoes pyrolysis; the spiral lifting blades can exert an upward lift along the tank wall on the organic solid waste in contact, so that the large particles of organic solid waste at the bottom of the tank are gradually lifted along the inner wall of the rotating tank to the top of the tank, and then due to the reduction in the diameter of the lifting blades, the organic solid waste is pushed to the middle of the rotating tank and falls back to the bottom of the tank; at the same time, the counter-rotating crushing blades can stir and crush the organic solid waste when it rises or falls, enhance heat transfer, and continuously peel off the surface pyrolysis carbon residue that is fully pyrolyzed; as the pyrolysis cycle proceeds, the organic solid waste is eventually completely converted into pyrolysis carbon residue; then, the temperature continues to rise, and under the fluidization action of the lifting blades and crushing blades, the pyrolysis carbon residue is fully mixed with the gasification agent and undergoes a gasification reaction until it is completely converted into inorganic waste residue; the pyrolysis and gasification stages are alternately carried out by controlling the temperature change, and the generated pyrolysis gas and gasification gas are used for combustion energy supply and fuel cell power generation respectively to meet the needs of the device's own operation and achieve harmless treatment and resource utilization of organic solid waste. Its beneficial effects include:

[0029] 1. The process is simple and the applicability of raw materials is wide: it can be applied to organic solid waste of various components and sizes, without the need for deep sorting and crushing, with simple processing steps and simplified auxiliary equipment, and is suitable for miniaturization for mobile or distributed layout.

[0030] 2. Uniform heat transfer to prevent sticking: The double-conical rotating tank is arranged tilted, and the diameter of the lifting blade increases first and then decreases with the diameter of the rotating section where the rotating tank wall is located. This can provide thrust for the organic solid waste, realize a large-scale circulation from the bottom to the top near the tank wall and from the top to the bottom inside the tank, so that it is violently stirred to be heated evenly, and in the rapid collision of the crushing blades, large pieces of raw materials are impacted and dispersed to prevent sticking.

[0031] 3. Crushing the surface carbon residue and high pyrolysis efficiency: When the organic solid waste in the rotating tank rises and falls along the inner wall of the tank, it will be quickly collided with the counter-rotating crushing blades, which can shear and crush to peel off the surface carbon residue of the organic solid waste, continuously expose the unpyrolyzed part inside, and achieve enhanced heat transfer. However, a single external or internal rotating reactor can only stir the raw materials and it is difficult to produce a shearing and crushing effect.

[0032] 4. Weight and volume reduction: Through alternating pyrolysis and gasification, the volume and mass of organic solid waste are greatly reduced. Finally, the small remaining inorganic waste residue can be compressed and landfilled harmlessly.

[0033] 5. Self-powered operation, can supply energy to the outside: The pyrolysis gas generated by the pyrolysis of organic solid waste is used for combustion to provide the power and heat required by the device. At the same time, the pyrolysis residual carbon is used for water vapor gasification to produce gasification gas rich in hydrogen and methane, which is used to generate electricity in fuel cells to provide electricity for the device. The overall pyrolysis gasification device can be self-operated without providing additional energy, and can even provide power and electricity to the outside, which is clean and environmentally friendly.

[0034] 6. The pyrolysis and gasification reaction conditions are easy to control: the working state of the device in the pyrolysis and gasification stages can be flexibly changed by adjusting the speed of the drive system, the flue gas temperature and change time, the amount of gasifier, etc., to adapt to the changes in the organic solid waste components.

[0035] 7. High resource utilization rate: Pyrolysis carbon residue is not easy to burn directly. It can be further gasified to prepare gasification gas rich in CH4, H2, CO, etc., which can be used for fuel cell power generation, thereby improving the resource utilization rate of organic solid waste.

[0036] 8. Effective dechlorination and clean discharge: The pyrolysis process of organic solid waste is an anaerobic process that can produce reducing components such as H2 and CO. In addition, the temperature is low and the residence time is long enough to adsorb the chlorine element in the organic solid waste in the form of hydrogen chloride, which can effectively inhibit the generation of harmful substances such as dioxins from the source and achieve effective dechlorination of organic solid waste.

[0037] 9. High space utilization: The pyrolysis and gasification processes are carried out alternately in the same reaction device. At the same time, the lifting blades and crushing blades are directly used to assist the fluidization of the pyrolysis carbon residue, which is convenient for full contact of the gas, can simplify the device structure and auxiliary equipment, save device space, is suitable for miniaturization, and reduces the manufacturing and operating costs of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic diagram of an alternating pyrolysis and gasification device provided in an embodiment of the present invention;

[0039] Figure 2 for Figure 1 A schematic diagram of the process flow of the alternating pyrolysis and gasification device;

[0040] Figure 3 A flow chart of the steps of the alternating pyrolysis and gasification method provided in an embodiment of the present invention.

[0041] [Description of main component symbols]

[0042] 1-air outlet; 2-feeding port; 3-stirring shaft; 4-transmission system; 5-lifting blade; 6-crushing blade; 7-flue; 8-discharge port; 9-discharge gate; 10-driving system; 11-gasifying agent inlet; 12-external shell; 13-rotating tank body. DETAILED DESCRIPTION

[0043] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0044] In view of the existing problems, the present invention provides an alternating pyrolysis and gasification device and method for organic solid waste, which can be miniaturized and suitable for mobile or distributed layout, has the characteristics of high space utilization, substantial weight and volume reduction, clean self-power supply, effective dechlorination, collision enhancement, uniform heat transfer, anti-sticking, convenient regulation, etc., and can achieve timely harmless treatment of organic solid waste through continuous alternating pyrolysis and gasification processes.

[0045] In order to realize the above technical solution, Figure 1 and Figure 2 As shown, the organic solid waste alternating pyrolysis gasification device provided by the present invention has substantially the same device structure in each embodiment, including an air outlet 1, a feed inlet 2, a stirring shaft 3, a transmission system 4, a lifting blade 5, a crushing blade 6, a flue 7, a discharge port 8, a discharge gate 9, a drive system 10, a gasifying agent inlet 11, an external shell 12 and a rotating tank body 13.

[0046] The rotating tank body 13 uses a hollow double-conical mixing drum with an axial height of 2000mm, a maximum diameter of 1400mm, an upper end face diameter of 700mm, and a lower end face diameter of 300mm; the rotating tank body 13 and the stirring shaft 3 are coaxially arranged and inclined at a 45° angle, and the diameter of the stirring shaft 3 is 50mm; both ends of the rotating tank body 13 and the stirring shaft 3 are supported by bearings located on the external shell 12, and the rotating tank body 13 and the stirring shaft 3 are connected by a transmission gear 4; the stirring shaft 3 is driven to rotate by a driving motor 10, and the rotating tank body 13 is driven to rotate in the opposite direction through the transmission gear 4; the upper end of the rotating tank body 13 is connected to the lower end of the feed port 2, the diameter of the feed port 2 is 200mm, and the air outlet 1 is connected to the side of the feed port 2; the lower end face of the rotating tank body 13 is open, and is respectively connected to the discharge port 8 and four evenly distributed gasifying agent inlets 11; the discharge gate 9 is located between the rotating tank body 13 and the outlet The material lifting blade 5 is a spiral belt-shaped blade, the outer side of which is fixed on the inner wall of the rotating tank body 13, the upper end of which is 100 mm away from the feed inlet 2 and the transmission gear 4, and the lower end is connected to the lower end surface of the rotating tank body 13, and is close to the discharge gate 9 and the surface of the outer shell 12; the thickness of the material lifting blade 5 is 5 mm, and the outer diameter changes with the change of the inner wall diameter of the rotating tank body 13, and its minimum inner diameter is 200 mm; the crushing blade 6 is composed of 8 groups of stirring rods, each group of three, evenly distributed on the stirring shaft 3 The outer diameter of the outer shell 12 is in close contact with the inner diameter of the lifting blade 5, with a gap of 2 mm; the gas outlet 1 is divided into two paths, one of which is connected to the adsorption device via the pyrolysis gas pipeline, and the other is connected to the fuel cell via the gasification gas pipeline; the dechlorination pyrolysis gas outlet of the adsorption device is connected to the gas inlet of the condensation device, the gas outlet of the condensation device is connected to the burner, the flue gas outlet of the burner is connected to the flue gas inlet of the outer shell 12, and the flue gas outlet of the outer shell 12 is connected to the purification device; the flue 7 is between the outer shell 12 and the rotating tank body 13, and heat exchange fins are arranged on the outside of the rotating tank body 13; the discharge port 8 is connected to the solid collection device.

[0047] The operation process of the above-mentioned organic solid waste alternating pyrolysis and gasification device is described in detail below through specific embodiments.

[0048] Example 1

[0049] As the pyrolysis gasification device starts to operate, the drive motor 10 is turned on to drive the rotating shaft 3 to rotate, and the rotating tank 13 is driven to rotate in the opposite direction through the traditional gear 4, with a speed of 15r / min; the high-temperature flue gas generated by the burner enters the flue 7, preheats the rotating tank 13, and stabilizes the temperature at 300℃; 0.5t of domestic garbage is sent into the rotating tank 13; the domestic garbage is gradually heated up, pyrolysis occurs to produce pyrolysis gas, and the surface residual carbon is continuously peeled off under the joint shearing and crushing action of the lifting blade 5 and the crushing blade 6; the temperature gradually rises until the domestic garbage is pyrolyzed at 600℃ Completely, all converted into pyrolysis charcoal; then, the temperature is further increased to 800℃, and water vapor and oxygen are introduced for gasification reaction; the charcoal is continuously gasified to produce gasification gas, and when the temperature rises to 1200℃ and the gasification efficiency reaches the peak, the temperature of the rotating tank 13 begins to be reduced until it is completely converted into inorganic waste residue; the pyrolysis gas is burned in the burner after dechlorination, providing power and high-temperature flue gas for the device, and the gasification gas generates electricity in the fuel cell, providing electrical energy for the device, effectively realizing self-sustaining operation; the low-temperature flue gas discharged from the flue is purified in the purification device and then emptied. The entire device curbs the emission of harmful substances such as dioxins through continuous pyrolysis and gasification of domestic waste in the same reaction chamber, and the weight reduction rate reaches 80.2wt%, realizing the harmless treatment of domestic waste.

[0050] Example 2

[0051] As the pyrolysis gasification device starts to operate, the drive motor 10 is turned on to drive the rotating shaft 3 to rotate, and the rotating tank 13 is driven to rotate in the opposite direction through the traditional gear 4, with a speed of 30r / min; the high-temperature flue gas generated by the burner enters the flue 7, preheats the rotating tank 13, and stabilizes the temperature at 300℃; 0.8t of sawdust is fed into the rotating tank 13; the sawdust particles are gradually heated up, pyrolysis occurs to produce pyrolysis gas, and the surface residual carbon is continuously stripped under the joint shearing and crushing action of the lifting blade 5 and the crushing blade 6; the temperature gradually rises until the sawdust is completely pyrolyzed at 600℃ and all converted into pyrolysis gas. Carbon residue; Subsequently, the temperature is further increased to 800°C, and water vapor and oxygen are introduced for gasification reaction; Carbon residue is continuously gasified to produce gasification gas, and when the temperature rises to 1200°C and the gasification efficiency reaches a peak, the temperature of the rotating tank 13 begins to be reduced until it is completely converted into inorganic waste residue; The pyrolysis gas can be collected as liquid products after dechlorination and condensation, and the non-condensable gas is burned in the burner to provide power and high-temperature flue gas for the device; The gasification gas generates electricity in the fuel cell, providing electrical energy for the device, effectively realizing self-sustaining operation; The low-temperature flue gas discharged from the flue is purified in the purification device and then discharged. The entire device continuously pyrolyzes and gasifies sawdust in the same reaction chamber, and the liquid phase yield is 50.2wt / %, of which high-value phenol products account for 36.7wt / % of the liquid phase products, realizing the high-value utilization of sawdust.

[0052] Example 3

[0053] As the pyrolysis gasification device starts to operate, the drive motor 10 is turned on to drive the rotating shaft 3 to rotate, and the rotating tank body 13 is driven to rotate in the opposite direction through the traditional gear 4, with a speed of 20r / min; the high-temperature flue gas generated by the burner enters the flue 7, preheats the rotating tank body 13, and stabilizes the temperature at 300°C; 0.5t of discarded medical masks are sent into the rotating tank body 13; the discarded medical masks are gradually heated up, pyrolysis occurs to produce pyrolysis gas, and under the joint shearing and crushing action of the lifting blades 5 and the crushing blades 6, the surface carbon residue is continuously stripped; the temperature gradually increases until the 600°C discarded medical masks are completely pyrolyzed and completely converted into pyrolysis carbon residue; then, the temperature is further increased to 800°C, and water vapor and oxygen are introduced for gasification reaction; the carbon residue is continuously gasified to produce gasification gas, and when the temperature rises to 1200°C and the gasification efficiency reaches a peak, the rotating tank body 13 begins to be reduced. temperature until it is completely converted into inorganic waste residue; the generated pyrolysis gas further undergoes non-in-situ catalytic reaction in the catalytic device, and then the liquid product is collected through dechlorination and condensation, while the non-condensable gas is burned in the burner to provide power and high-temperature flue gas for the device; the gasification gas generates electricity in the fuel cell, providing electrical energy for the device, effectively achieving self-sustaining operation; the low-temperature flue gas discharged from the flue is purified in the purification device and then discharged. The entire device continuously pyrolyzes and gasifies discarded medical masks in the same reaction chamber, with a liquid phase yield of 48.4wt / %, of which the target product aromatics account for 76.4wt / % in the liquid phase product, achieving high-value utilization and harmless disposal of discarded medical masks.

[0054] In the description of the present invention, the terms "upper", "lower", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and should not be understood as a limitation on the present invention; unless otherwise clearly specified and limited, the terms "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be a connection inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0055] For the above-mentioned embodiments of the present invention, the common knowledge such as the known specific structures and characteristics in the scheme is not described in detail; each embodiment is described in a progressive manner, and the technical features involved in each embodiment can be combined with each other under the premise that there is no conflict between each other, and the same and similar parts between the embodiments can be referred to each other. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles described in the present invention, and these improvements and modifications should also be regarded as falling within the scope of protection of the present invention.

Claims

1. An alternating pyrolysis gasification device, characterized in that: include: An external shell (12), wherein the external shell (12) is provided with a feed inlet (2), a feed outlet (8), a gasifying agent inlet (11), a gas outlet (1), a smoke inlet and a smoke outlet; A rotating tank body (13), the rotating tank body (13) being rotatably mounted in the outer shell (12) and being arranged to form a flue (7) between the rotating tank body (13) and the outer shell (12), the rotating axis of the rotating tank body (13) being inclined relative to the vertical direction, and a spiral material lifting blade (5) extending around the rotating axis being connected to the inner wall surface; wherein the feed port (2), the discharge port (8), the gasifying agent inlet (11) and the gas outlet (1) are all connected to the inner cavity of the rotating tank body (13), and the smoke inlet and the smoke outlet are respectively connected to the flue (7); and, a stirring shaft (3), the stirring shaft (3) extending along the rotation axis of the rotating tank body (13) and connected to a material crushing blade (6), the material crushing blade (6) comprising a plurality of stirring rods or plate-type stirring paddles provided with slots; the material crushing blade (6) is distributed in the gaps between the material lifting blades (5) and has an extension length smaller than the inner diameter of the corresponding material lifting blade (5) on the rotating plane, so as to allow the stirring shaft (3) to be driven to rotate in the opposite direction relative to the rotating tank body (13); The rotating tank (13) comprises a double-conical cylinder with conical bottoms connected to each other, and the upper and lower ends of the double-conical cylinder are respectively supported on the outer shell (12) through bearings; the upper and lower ends of the stirring shaft (3) are both supported on the outer shell (12) through bearings; The alternating pyrolysis gasification device further comprises a drive system (10) which is transmission-connected to the stirring shaft (3) and a transmission system (4) which is transmission-connected between the rotating tank body (13) and the stirring shaft (3); the drive system (10) is capable of driving the stirring shaft (3) to rotate, and driving the rotating tank body (13) to rotate in the opposite direction relative to the stirring shaft (3) through the transmission system (4), so that the lifting blades (5) convey at least part of the solid material in the rotating tank body (13) upward.

2. The alternating pyrolysis gasification device according to claim 1, characterized in that: The feed port (2) is connected to the upper end of the rotating tank body (13), and the gas outlet (1) is connected to the inner cavity of the rotating tank body (13) through the feed port (2); and the outer shell (12) is provided with a plurality of gasifying agent inlets (11) connected to the lower end of the rotating tank body (13).

3. The alternating pyrolysis gasification device according to claim 1, characterized in that: A discharge gate (9) is provided on the connection interface between the rotating tank body (13) and the discharge port (8), and the discharge gate (9) is configured to be able to close the discharge port (8). The discharge port (8) is connected to a solid collection device.

4. The alternating pyrolysis gasification device according to claim 1, characterized in that: The gas outlet (1) is divided into two paths, one of which is connected to the adsorption device via a pyrolysis gas pipeline, and the other is connected to the fuel cell system via a gasification gas pipeline; the dechlorination pyrolysis gas outlet of the adsorption device is connected to the gas inlet of the condensation device, the gas outlet of the condensation device is connected to the burner, the flue gas outlet of the burner is connected to the flue gas inlet of the external shell (12), and the flue gas outlet of the external shell (12) is connected to the purification device.

5. The alternating pyrolysis gasification device according to claim 1, characterized in that: Heat exchange fins are arranged on the outer side of the rotating tank (13).

6. The alternating pyrolysis gasification device according to claim 1, characterized in that: The distance between the upper end of the lifting blade (5) and the feed port (2) is not less than 100 mm, and the angle between the rotation axis of the rotating tank body (13) and the horizontal plane is 30-60°.

7. A method for pyrolysis and gasification using the alternating pyrolysis and gasification device according to any one of claims 1 to 6, characterized in that: The two stages of pyrolysis and gasification are operated alternately and intermittently. The organic solid waste is pyrolyzed in the pyrolysis stage to produce pyrolysis gas and pyrolysis carbon residue. The pyrolysis carbon residue is further gasified in the gasification stage to produce gasification gas and inorganic waste residue, including the following steps: S1. The alternating pyrolysis gasification device starts to operate, driving the stirring shaft and the rotating tank to rotate in opposite directions to each other; S2. The high-temperature flue gas is introduced into the flue through the flue gas inlet to preheat the rotating tank; S3. The quantitative organic solid waste raw material is fed into the rotating tank through the feed port, heated, dried to remove part of the water, and gradually pyrolyzed; S4. The rotating tank body drives the lifting blades to rotate; driven by the lifting blades, at least part of the organic solid waste at the bottom of the tank is gradually lifted to the top of the tank body along the inner wall of the tank, and then the organic solid waste falls from the middle of the rotating tank body back to the bottom; at the same time, the stirring shaft drives the crushing blades to rotate in the opposite direction to the rotation direction of the pyrolysis tank, stirring and crushing the organic solid waste when it rises or falls, so that the organic solid waste is heated evenly and the residual carbon on the surface that is fully pyrolyzed is continuously peeled off; under the combined action of stirring and crushing by the lifting blades and the crushing blades, the organic solid waste continuously repeats the cycle process from the bottom to the top near the wall of the rotating tank body, and returns from the top to the bottom from the inside of the rotating tank body, continuously decomposes under heat to produce pyrolysis gas, and gradually reduces in volume until the pyrolysis is complete and only the pyrolysis residual carbon remains in the rotating tank body; S5. By adjusting the flue gas flow and distribution, the temperature of the rotating tank is further increased to start the gasification process of the residual carbon; S6. The gasifying agent is continuously introduced from the gasifying agent inlet, and the pyrolysis carbon residue is fluidized and fully mixed with the gasifying agent by the dual stirring of the lifting blade and the crushing blade; the pyrolysis carbon residue is gasified under the action of the gasifying agent to produce gasification gas; when the gasification efficiency reaches the peak value, the temperature of the rotating tank body begins to decrease; as the pyrolysis carbon residue is completely gasified, only inorganic waste residue remains in the rotating tank body; S7. The inorganic waste is discharged and collected through the discharge port, and the temperature of the rotating tank body continues to decrease, ready to feed again; S8. The pyrolysis gas produced by the pyrolysis of organic solid waste is dechlorinated, condensed, and the liquid products are collected, while the non-condensable gas is burned in the burner to provide power and high-temperature flue gas for the device; the gasification gas produced by the gasification of pyrolysis residual carbon is used to generate electricity in the fuel cell to provide electrical energy for the device; the low-temperature flue gas discharged from the flue is purified in the purification device and then discharged.

8. The method of alternating pyrolysis and gasification according to claim 7, characterized in that: In step S6, the gasifying agents introduced are water vapor and oxygen, and in steps S3 to S6, the rotating tank (13) cyclically fluctuates between 300 and 1200° C., wherein the pyrolysis stage in steps S3 and S4 meets 300 to 600° C., and the gasification stage in steps S5 and S6 meets 800 to 1200° C.

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