A wind-driven auxiliary grate furnace garbage pyrolysis ash circulating catalytic system

Abstract

The application discloses a wind-driven auxiliary grate furnace garbage pyrolysis ash circulating catalysis system, and belongs to the technical field of garbage treatment. The system comprises a grate furnace, and a feeding port is arranged on one side of the grate furnace. A microwave drying area is communicated with the bottom of the feeding port. A water vapor collecting device is communicated with one side of the microwave drying area. A cyclone separation device is communicated with the other side of the microwave drying area. A main conveying belt is communicated with the bottom of the microwave drying area. An ash crushing device is communicated with the main conveying belt. A wind auxiliary power device is drivingly connected to the ash crushing device. The ash crushing device is communicated with an ash collecting box. The system directly drives a garbage pyrolysis whole-process auxiliary system by using wind mechanical energy. Through the closed-loop design of ash crushing-air conveying-circulating catalysis, the resource utilization of pyrolysis ash is realized. The pyrolysis ash is crushed and then recycled to the furnace as a catalyst, so that the pyrolysis efficiency of the main combustion system is improved.

Description

Technical Field

[0001] This invention belongs to the field of waste treatment technology, and in particular relates to a wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system. Background Technology

[0002] With the acceleration of urbanization in my country, the annual output of municipal solid waste continues to grow, making the harmless treatment of waste a core task of ecological and environmental protection. Grate furnace pyrolysis technology has become the mainstream technology for municipal solid waste treatment due to its large processing capacity, stable operation, and good volume reduction effect. Meanwhile, wind power, as one of the most mature renewable energy sources, has a huge installed capacity in Northwest, North, and coastal areas of my country, but it suffers from serious wind curtailment problems, with a large amount of surplus mechanical energy not being effectively utilized.

[0003] Existing municipal solid waste grate pyrolysis technology typically suffers from the following problems: 1) High dependence on fossil fuels in auxiliary systems: The auxiliary systems of traditional grate furnace waste pyrolysis technology (including pretreatment, compressed air preparation, ash treatment, flue gas purification, etc.) account for 20% to 35% of the total operating cost, and all of them rely on grid electricity and fossil fuels, resulting in large carbon emissions, which does not meet the requirements of dual carbon targets. 2) Extremely low ash resource utilization rate: The ash generated by pyrolysis is only disposed of as hazardous solid waste through landfill, which not only occupies a large amount of land resources, but also poses a risk of heavy metal leakage, thus failing to realize the resource utilization of ash. 3) Low pyrolysis efficiency: The waste pyrolysis process lacks an effective catalyst, resulting in high pyrolysis temperature, long reaction time, poor pyrolysis gas quality, and easy generation of secondary pollutants such as tar. 4) Poor system energy efficiency: The waste heat generated by the auxiliary system and the low-grade waste heat from the pyrolysis process are not utilized in a cascade manner, resulting in serious energy loss; 5) The problem of wind curtailment is prominent: the intermittent nature of wind power generation results in a large amount of surplus mechanical energy that cannot be connected to the grid for consumption, causing energy waste. Existing technologies have not achieved direct coupling between wind mechanical energy and waste treatment auxiliary systems. Summary of the Invention

[0004] The purpose of this invention is to provide a wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system to solve the problems existing in the prior art.

[0005] To achieve the above objectives, the present invention provides the following solution: The present invention provides a wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system, including a grate furnace, a feed inlet on one side of the grate furnace, a microwave drying zone connected to the bottom of the feed inlet, a water vapor collection device connected to one side of the microwave drying zone, a cyclone separator connected to the other side of the microwave drying zone, a main conveyor belt connected to the bottom of the microwave drying zone, the cyclone separator connected to the top of the grate furnace and the main conveyor belt respectively, an ash pulverizing device connected to the main conveyor belt, a wind-driven auxiliary power device connected to the ash pulverizing device, an ash collection box connected to the wind-driven auxiliary power device and the inside of the grate furnace respectively.

[0006] Optionally, the wind-assisted power unit includes a wind turbine, which is driven by a transmission mechanism. The transmission mechanism is driven by an air compressor. The air compressor is connected to a first-stage heat exchanger. The first-stage heat exchanger is connected to a waste preheating chamber via a heat transfer oil circulation pump. The first-stage heat exchanger is connected to a compressed air storage tank via a cyclone separator. The compressed air storage tank is connected to an air outlet, which is connected to the ash collection box.

[0007] Optionally, an air valve and a flow meter are provided between the compressed air storage tank and the air outlet.

[0008] Optionally, the ash crushing device includes a speed-increasing gearbox that is connected to the transmission mechanism. The speed-increasing gearbox is connected to a double-roll crusher. The main conveyor belt is located above the double-roll crusher, and a discharge conveyor belt is located below the double-roll crusher. The discharge conveyor belt is connected to the ash collection box.

[0009] Optionally, a microwave heater is provided on the outside of the microwave drying zone.

[0010] Optionally, the water vapor collection device is located above the microwave drying zone.

[0011] Optionally, the waste preheating chamber contains waste to be preheated.

[0012] Optionally, the fine ash after being crushed by the roller crusher is sent to the ash collection box via the discharge conveyor belt.

[0013] This invention discloses the following technical effects: Municipal solid waste is fed into the microwave drying zone of the grate furnace through the inlet, where it is uniformly heated to 200°C, achieving deep drying and removing free and bound water. Water vapor generated during drying is collected through pipes to a water vapor collection device; the collected clean water can be directly used for agricultural irrigation. The moisture content of the dried waste is reduced to below 10%, providing optimal conditions for the subsequent main combustion pyrolysis reaction and significantly reducing fossil fuel consumption in the main combustion system. The dried waste falls onto the main conveyor belt of the grate furnace and slowly moves into the main combustion pyrolysis zone, where it undergoes continuous pyrolysis in an oxygen-free environment (500-800°C) provided by fossil fuels, producing pyrolysis gas and pyrolysis ash. The dust-laden pyrolysis gas generated during the pyrolysis process enters the cyclone separator through pipelines. The cyclone separator separates the small solid particles entrained in the pyrolysis gas. The separated solid particles continue to enter the pyrolysis zone with the garbage blocks on the main conveyor belt for complete pyrolysis. The pyrolysis gas is then sent to the next stage of the grate furnace for combustion or gasification. The ash after complete pyrolysis is conveyed to the ash crushing device by the main conveyor belt. The crushed fine ash is conveyed to the ash collection box by the conveyor belt and blown to the feed inlet by compressed air generated by the wind-assisted power device. After mixing with fresh garbage, it is recycled back to the furnace as a pyrolysis catalyst.

[0014] This invention utilizes an integrated closed-loop structural design to directly drive the entire auxiliary system of waste pyrolysis with wind power. Simultaneously, through a closed-loop design of ash crushing, pneumatic conveying, and circulating catalysis, it achieves resource utilization of pyrolysis ash. The ash crushing device is driven by a wind-powered auxiliary power unit, eliminating the need for intermediate electrical energy conversion, solving the problem of wind curtailment, and achieving zero fossil energy consumption in the auxiliary system. The crushed pyrolysis ash is recycled back to the furnace as a catalyst, improving the pyrolysis efficiency of the main combustion system. Furthermore, the energy consumption of the main combustion system is reduced through a tiered pretreatment process involving microwave drying and waste heat preheating. Attached Figure Description

[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system of the present invention; Figure 2 This is a schematic diagram of the wind-assisted power device of the present invention; Figure 3 This is a schematic diagram of the ash pulverizing device of the present invention.

[0016] Figure label: 1. Water vapor collection device; 2. Feed inlet; 3. Grate furnace; 4. Microwave heater; 5. Microwave drying zone; 6. Cyclone separator; 7. Main conveyor belt; 8. Ash collection box; 9. Ash crushing device; 10. Wind-powered auxiliary power unit; 11. Wind turbine generator; 12. Transmission mechanism; 13. Air compressor; 14. First-stage heat exchanger; 15. Waste preheating bin; 16. Cyclone separator; 17. Compressed air storage tank; 18. Air valve; 19. Flow meter; 20. Air outlet; 21. Speed-increasing gearbox; 22. Roller crusher; 23. Lump ash; 24. Discharge conveyor belt. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] Reference Figures 1 to 3 As shown, this embodiment provides a wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system, including a grate furnace 3. A feed inlet 2 is provided on one side of the grate furnace 3. The bottom of the feed inlet 2 is connected to a microwave drying zone 5. A water vapor collection device 1 is connected to one side of the microwave drying zone 5. A cyclone separator 6 is connected to the other side of the microwave drying zone 5. A main conveyor belt 7 is connected to the bottom of the microwave drying zone 5. The cyclone separator 6 is connected to the grate furnace 3 and the top of the main conveyor belt 7. The main conveyor belt 7 is connected to an ash crushing device 9. The ash crushing device 9 is driven by a wind-driven auxiliary power device 10. The ash crushing device 9 is connected to an ash collection box 8. The ash collection box 8 is connected to the wind-driven auxiliary power device 10 and the inside of the grate furnace 3.

[0020] The municipal solid waste to be processed is fed into the microwave drying zone 5 of the grate furnace 3 through the feed inlet 2. The waste is uniformly heated to 200°C, achieving deep drying and removing free and bound water. Water vapor generated during the drying process is collected through pipes to a water vapor collection device 1. The collected clean water can be directly used for agricultural irrigation. The moisture content of the dried waste is reduced to below 10%, providing optimal conditions for the subsequent main combustion pyrolysis reaction and significantly reducing fossil fuel consumption in the main combustion system. The dried waste falls onto the main conveyor belt 7 of the grate furnace 3 and slowly moves into the main combustion pyrolysis zone. Continuous pyrolysis occurs in an oxygen-free environment (500-800°C) provided by fossil fuels, producing pyrolysis gas and pyrolysis ash. The dust-laden pyrolysis gas generated during the pyrolysis process enters the cyclone separator 6 through a pipeline. The cyclone separator 6 separates the small solid particles entrained in the pyrolysis gas. The separated solid particles continue to enter the pyrolysis zone with the garbage blocks on the main conveyor belt 7 for complete pyrolysis. The pyrolysis gas is then sent to the next stage of the grate furnace 3 for combustion or gasification. The ash after complete pyrolysis is transported to the ash crushing device 9 by the main conveyor belt 7. The crushed fine ash is then transported to the ash collection box 8 by the conveyor belt. Compressed air generated by the wind-assisted power device 10 blows the ash to the feed inlet 2, where it mixes with fresh garbage and is recycled back to the furnace as a pyrolysis catalyst.

[0021] This invention utilizes an integrated closed-loop structural design to directly drive the entire auxiliary system of waste pyrolysis with wind power. Simultaneously, through a closed-loop design of ash crushing, pneumatic conveying, and circulating catalysis, it achieves resource utilization of pyrolysis ash. The wind-powered auxiliary power unit 10 drives the ash crushing device 9, eliminating the need for intermediate electrical energy conversion, solving the problem of wind curtailment, and achieving zero fossil energy consumption in the auxiliary system. The crushed pyrolysis ash is recycled back to the furnace as a catalyst, improving the pyrolysis efficiency of the main combustion system. Furthermore, the energy consumption of the main combustion system is reduced through a tiered pretreatment process involving microwave drying and waste heat preheating.

[0022] Further optimization of the scheme: the wind-assisted power unit 10 includes a wind turbine, which is connected to a transmission mechanism 12. The transmission mechanism 12 is connected to an air compressor 13. The air compressor 13 is connected to a first-stage heat exchanger 14. The first-stage heat exchanger 14 is connected to a waste preheating chamber 15 via a heat transfer oil circulation pump. The first-stage heat exchanger 14 is connected to a compressed air storage tank 17 via a cyclone separator 16. The compressed air storage tank 17 is connected to an air outlet 20. The air outlet 20 is connected to an ash collection box 8.

[0023] The design has been further optimized by installing an air valve 18 and a flow meter 19 between the compressed air storage tank 17 and the air outlet 20.

[0024] The mechanical energy generated by the wind turbine 11 is simultaneously diverted through the transmission mechanism 12 to drive the air compressor 13. The air compressor 13 compresses the outside air to 0.6~0.8MPa, without consuming any grid power. The compressed high-temperature and high-pressure air (temperature approximately 120~150℃) enters the first-stage heat exchanger 14, where it exchanges heat with the heat transfer oil on the other side of the first-stage heat exchanger 14, heating the heat transfer oil to 90~110℃. The compressed air, cooled by the heat exchange (temperature approximately 40~50℃), enters the cyclone separator 16 to remove impurities and oil mist from the air, and is then sent to the compressed air storage tank 17 for storage.

[0025] The heated heat transfer oil is pumped to the waste preheating chamber 15 via a circulation pump, where it indirectly exchanges heat with the waste to be preheated, raising the temperature of the waste to 80-100°C. The cooled heat transfer oil (approximately 50-60°C) then flows back to the first-stage heat exchanger 14 through a pipeline, completing the closed-loop circulation of the heat transfer oil. The preheated waste is then fed into the feed inlet 2 for further processing, which can further reduce the energy consumption of microwave drying.

[0026] When ash pneumatic conveying is required, turn on the air valve 18 and adjust the compressed air flow rate according to the ash conveying amount through the flow meter 19. The compressed air is sprayed out from the air outlet 20, which blows the fine ash in the ash collection box 8 to the feed inlet 2 of the grate furnace 3, mixes it evenly with the unpyrolyzed dry waste, and enters the main combustion pyrolysis zone as a pyrolysis catalyst.

[0027] The wind turbine 11 provides all the mechanical power for the two high-energy-consuming auxiliary processes of compressed air preparation and ash crushing, avoiding the conversion loss of "mechanical energy-electrical energy-mechanical energy" and achieving zero fossil energy consumption in the auxiliary system. The pyrolysis ash is recycled back to the furnace after crushing, and as a pyrolysis catalyst, it can reduce the activation energy of the pyrolysis reaction, reduce the pyrolysis temperature of the main combustion system by 50-100℃, shorten the pyrolysis reaction time by 20%, and increase the content of combustible components in the pyrolysis gas, further reducing the fossil fuel consumption of the main combustion system. The use of heat transfer oil as an intermediate heat exchange medium realizes the efficient recovery of waste heat from compressed air and the uniform preheating of waste, avoiding problems such as local overheating and coking of waste and equipment corrosion caused by direct gas-solid heat exchange. The water vapor generated by microwave drying is recovered for agricultural irrigation, realizing the cascade utilization and closed-loop circulation of energy and materials throughout the entire process, and the system has no secondary solid waste emissions.

[0028] The heat transfer oil circulation loop and the compressed air loop are independent of each other, with no media crossing.

[0029] Further optimization of the scheme: the ash crushing device 9 includes a speed-increasing gearbox 21 that is connected to the transmission mechanism 12. The speed-increasing gearbox 21 is connected to a roller crusher 22. A main conveyor belt 7 is provided above the roller crusher 22, and a discharge conveyor belt 24 is provided below the roller crusher 22. The discharge conveyor belt 24 is connected to the ash collection box 8.

[0030] The mechanical energy generated by the rotation of the blades of the wind turbine 11 is transmitted to the speed-increasing gearbox 21 through the transmission mechanism 12. The speed-increasing gearbox 21 increases the rotation speed to 1500~3000 r / min and drives the two counter-rotating gears of the pulverizer to rotate at high speed, pulverizing the lumpy ash 23 conveyed by the main conveyor belt 7 into fine powder with a particle size ≤0.1mm. The pulverized fine ash is then conveyed to the ash collection box 8 by the discharge conveyor belt 24.

[0031] To further optimize the design, a microwave heater 4 is installed on the outer side of the microwave drying zone 5.

[0032] In a further optimized design, the water vapor collection device 1 is positioned above the microwave drying zone 5.

[0033] The design has been further optimized, with waste to be preheated contained in the waste preheating chamber 15.

[0034] The scheme was further optimized so that the fine ash after being crushed by the roller crusher 22 was sent to the ash collection box 8 via the discharge conveyor belt 24.

[0035] This invention uses a wind turbine generator 11 as the sole power source for two high-energy-consuming auxiliary processes: compressed air preparation and ash pulverization. It directly drives the process using wind power mechanical energy, eliminating the need for intermediate electrical energy conversion and achieving zero fossil energy consumption in the auxiliary system. This can reduce the total energy consumption of waste treatment by more than 25%. At the same time, it can absorb the surplus mechanical energy generated by wind power on-site, solving the problem of wind curtailment and improving energy utilization efficiency compared to the traditional electric drive mode.

[0036] This invention pioneers a pyrolysis ash recycling catalytic process, which pulverizes the pyrolysis ash that would otherwise be landfilled and reuses it as a pyrolysis catalyst in the furnace. This not only reduces the amount of ash landfilled and the risk of secondary pollution, but also lowers the activation energy of the pyrolysis reaction in the main combustion system, reducing the pyrolysis temperature by 50-100°C, shortening the pyrolysis reaction time by 20%, and increasing the combustible component content in the pyrolysis gas by more than 15%. This further reduces the fossil fuel consumption of the main combustion system and achieves synergy between "solid waste treatment - resource utilization - efficiency improvement".

[0037] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0038] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A wind-powered assisted grate furnace waste pyrolysis ash recycling catalytic system, characterized in that: The furnace includes a grate furnace (3), with a feed inlet (2) on one side. The bottom of the feed inlet (2) is connected to a microwave drying zone (5). A water vapor collection device (1) is connected to one side of the microwave drying zone (5), and a cyclone separator (6) is connected to the other side of the microwave drying zone (5). A main conveyor belt (7) is connected to the bottom of the microwave drying zone (5). The cyclone separator (6) is connected to the top of the grate furnace (3) and the main conveyor belt (7). The main conveyor belt (7) is connected to an ash crushing device (9). The ash crushing device (9) is connected to a wind-assisted power device. The ash crushing device (9) is connected to an ash collection box (8). The ash collection box (8) is connected to the wind-assisted power device (10) and the grate furnace (3).

2. The wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system according to claim 1, characterized in that: The wind-assisted power unit (10) includes a wind engine, which is connected to a transmission mechanism (12). The transmission mechanism (12) is connected to an air compressor (13). The air compressor (13) is connected to a first-stage heat exchanger (14). The first-stage heat exchanger (14) is connected to a waste preheating chamber (15) via a heat transfer oil circulation pump. The first-stage heat exchanger (14) is connected to a compressed air storage tank (17) via a cyclone separator (16). The compressed air storage tank (17) is connected to an air outlet (20). The air outlet (20) is connected to the ash collection box (8).

3. The wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system according to claim 2, characterized in that: An air valve (18) and a flow meter (19) are provided between the compressed air storage tank (17) and the air outlet (20).

4. The wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system according to claim 2, characterized in that: The ash crushing device (9) includes a speed-increasing gearbox (21) that is connected to the transmission mechanism (12). The speed-increasing gearbox (21) is connected to a roller crusher (22). The main conveyor belt (7) is provided above the roller crusher (22), and the discharge conveyor belt (24) is provided below the roller crusher (22). The discharge conveyor belt (24) is connected to the ash collection box (8).

5. The wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system according to claim 1, characterized in that: A microwave heater (4) is provided on the outside of the microwave drying zone (5).

6. The wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system according to claim 1, characterized in that: The water vapor collection device (1) is located above the microwave drying zone (5).

7. The wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system according to claim 2, characterized in that: The waste preheating chamber (15) contains waste to be preheated.

8. The wind-driven assisted grate furnace waste pyrolysis ash recycling catalytic system according to claim 4, characterized in that: The fine ash after being crushed by the roller crusher (22) is sent to the ash collection box (8) via the discharge conveyor belt (24).

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