Fire coal coupling garbage cyclone oxygen-enriched combustion and fly ash melting treatment system and method

Abstract

The invention belongs to the technical field of garbage treatment, and relates to a fire coal coupling garbage cyclone oxygen-enriched combustion and fly ash melting treatment system and method, and the system comprises a cyclone furnace, an electrostatic dust collector, a slag water tank, an air separation device and a liquid oxygen heater. Fly ash can be introduced into the cyclone furnace to be subjected to high-temperature melting treatment, liquid ash slag formed after high-temperature melting treatment is discharged into the slag water tank to be cooled and collected, high-temperature melting treatment and liquid slag discharging of the fly ash are combined, on one hand, the treatment cost of the hazardous waste fly ash is reduced, and recycling closed-loop treatment of the ash slag is achieved; on the one hand, the potential threat of fly ash to the environment is reduced, on the other hand, harmless treatment of ash slag is achieved through liquid-state slag discharging, leaching of harmful substances such as dioxin and heavy metal is avoided, meanwhile, an oxygen-enriched combustion environment can be formed in the cyclone furnace through liquid oxygen, generation of thermal NOx is blocked, emission of NOx is reduced, and in addition, the environment-friendly effect is achieved. And secondary generation of dioxin can also be inhibited by rapidly reducing the temperature of the flue gas through the liquid oxygen heater.

Description

Technical Field

[0001] The invention belongs to the technical field of garbage treatment, and relates to a system and method for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment. Background Art

[0002] Municipal solid waste refers to solid waste generated in daily urban life or in activities that provide services for daily urban life. With the acceleration of urbanization, the amount of municipal solid waste generated is increasing year by year. Coal-fired coupled waste-to-energy technology can be used as an excellent solution, combining the dual advantages of coal-fired power generation and waste treatment, not only achieving fuel savings and improving power generation efficiency, but also significantly reducing CO 2 emission.

[0003] At present, traditional coal-fired coupled waste-to-energy technology often uses a solid slag boiler, including a furnace, water-cooled walls and a slag discharge port. Domestic waste is put into the furnace as solid fuel. Under high temperature conditions, the combustible matter in the waste is burned under the action of oxygen in the air. The solid slag produced after combustion is finally discharged through the slag discharge port.

[0004] However, there are many problems in the treatment of domestic waste by solid slag discharge boilers. First, when domestic waste is fed into solid slag discharge boilers for combustion, the emission of harmful substances such as dioxins and heavy metals increases significantly. These pollutants are difficult to be effectively decomposed during the combustion process, resulting in the conversion of ash into potential hazardous waste. Second, a large amount of fly ash and bottom slag will be generated during the incineration process of waste. The ash contains harmful substances such as heavy metals (such as lead, cadmium, zinc, etc.), halogen organic matter (such as dioxins, furans, etc.) and soluble salts, which pose a huge threat to the environment and human health and are hazardous wastes. Summary of the invention

[0005] The purpose of the present invention is to provide a system and method for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment, which can be used for large-scale clean treatment of domestic garbage. Through the combination of high-temperature melting treatment of fly ash and liquid slag discharge, the leaching of harmful substances such as dioxins and heavy metals is reduced, thereby reducing the potential threat of fly ash to the environment.

[0006] To achieve the above-mentioned purpose, the specific technical scheme of a system and method for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment provided by the present invention is as follows:

[0007] A system for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment includes a cyclone furnace, wherein the interior of the cyclone furnace is divided into a combustion zone, a reduction zone and a burnout zone from the head to the tail, and a garbage feeding assembly and a coal powder feeding assembly are connected to the position of the cyclone furnace near the combustion zone, and further includes:

[0008] The electrostatic precipitator is connected to the position of the cyclone furnace near the burnout zone. A fly ash return nozzle is provided on the cyclone furnace near the combustion zone. The first outlet of the electrostatic precipitator is connected to the fly ash return nozzle. The electrostatic precipitator is used to receive the high-temperature flue gas generated in the cyclone furnace and remove the fly ash in the high-temperature flue gas, and then introduce the fly ash into the cyclone furnace for high-temperature melting treatment.

[0009] The slag pool is connected to the reduction zone inside the cyclone furnace and is used to cool and collect liquid ash formed from the high-temperature melting treatment of fly ash in the cyclone furnace, thereby realizing the combination of high-temperature melting treatment of fly ash and liquid slag discharge.

[0010] The present invention is also characterized in that:

[0011] A liquid oxygen heater is arranged between the electrostatic precipitator and the tail of the cyclone furnace, a first inlet of the liquid oxygen heater is connected to a position close to the burnout zone of the cyclone furnace, a first outlet of the liquid oxygen heater is connected to a first inlet of the electrostatic precipitator, a second inlet of the liquid oxygen heater is connected to an air separation device, the air separation device is used to produce liquid oxygen, a pure oxygen secondary air nozzle is arranged close to the combustion zone on the cyclone furnace, and a second outlet of the liquid oxygen heater is connected to the pure oxygen secondary air nozzle.

[0012] The garbage feeding components include:

[0013] Garbage storage pits, used to store domestic garbage;

[0014] A magnetic separator, an inlet of which is connected to a first outlet of the garbage storage pit;

[0015] A crusher, an inlet of which is connected to a first outlet of the magnetic separator;

[0016] The inlet of the screw feeder is connected with the first outlet of the crusher. The head of the cyclone furnace is provided with a feed and a primary air port. The outlet of the screw feeder is connected with the feed and the primary air port.

[0017] A odor nozzle is arranged near the reduction zone on the cyclone furnace, the odor nozzle is connected to the outlet of the odor blower, and the inlet of the odor blower is respectively connected to the second outlet of the garbage storage pit, the second outlet of the magnetic separator, and the second outlet of the crusher.

[0018] The pulverized coal feeding components include:

[0019] Steel ball coal mill, used to grind the coal into coal powder;

[0020] The pulverized coal burner is arranged on the cyclone furnace near the combustion zone, and the inlet of the pulverized coal burner is connected with the outlet of the steel ball coal mill.

[0021] A method for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment comprises the following steps:

[0022] The coal is fed into a steel ball mill for grinding to obtain coal powder, and the coal powder is fed into a coal powder burner, through which an ultra-high temperature combustion environment is formed in the combustion zone of the cyclone furnace;

[0023] Liquid oxygen is produced by using an air separation device, and the liquid oxygen enters a liquid oxygen heater. The high-temperature flue gas generated in the cyclone furnace enters the liquid oxygen heater to perform heat exchange with the liquid oxygen, and the liquid oxygen is heated to obtain heated liquid oxygen. The heated liquid oxygen is sent to the combustion zone of the cyclone furnace, so that the combustion zone of the cyclone furnace forms an oxygen-rich combustion environment;

[0024] The domestic garbage is sent to a garbage storage pit for storage, fermentation and dehydration. The domestic garbage after fermentation and dehydration is sequentially passed through a magnetic separator to remove metal substances and a crusher to obtain pre-treated domestic garbage. The pre-treated domestic garbage is sent to the feed and primary air inlet through a spiral feeder. The pre-treated domestic garbage enters the combustion zone of the cyclone furnace through the feed and primary air inlet. The pre-treated domestic garbage is burned in the ultra-high temperature combustion environment and oxygen-rich combustion environment of the combustion zone to form liquid ash after combustion;

[0025] After the high-temperature flue gas comes out of the liquid oxygen heater, it enters the electrostatic precipitator, where the fly ash is filtered. The fly ash then enters the combustion zone through the fly ash return nozzle for high-temperature melting treatment.

[0026] The liquid ash is introduced into the slag pool to be cooled and collected.

[0027] The temperature of the ultra-high temperature combustion environment is 1600°C to 2000°C, and the excess oxygen coefficient of the oxygen-rich combustion environment is 0.5 to 0.9.

[0028] The high-temperature flue gas is cooled from 400°C to 600°C to below 200°C after heat exchange with liquid oxygen, and the temperature of the heated liquid oxygen is 100°C to 200°C.

[0029] The particle size of pretreated domestic waste is 5mm-50mm, and the particle size of coal powder is 0.1mm-10mm.

[0030] The system and method of the present invention for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment has the following advantages:

[0031] First, through the cooperation of the cyclone furnace, the electrostatic precipitator and the slag pool, the fly ash can be introduced into the cyclone furnace for high-temperature melting treatment. After the high-temperature melting treatment, the liquid ash is discharged into the slag pool for cooling and collection, realizing the combination of high-temperature melting treatment of fly ash and liquid slag discharge. On the one hand, the treatment cost of hazardous waste fly ash is reduced, the closed-loop disposal of ash resources is realized, and the potential threat of fly ash to the environment is reduced. On the other hand, the liquid slag discharge can realize the harmless treatment of ash and avoid the leaching of harmful substances such as dioxins and heavy metals.

[0032] Secondly, through the coordinated setting of the air separation unit and the liquid oxygen heater, the liquid oxygen can be heated by the high-temperature flue gas generated by the cyclone furnace, so that it enters the cyclone furnace to form an oxygen-rich combustion environment. The generation of thermal NOx is blocked by the oxygen-rich combustion environment, and a large amount of NOx is avoided from being generated in the high-temperature environment of the cyclone furnace 6, thereby reducing NOx emissions and reducing environmental pollution. At the same time, the rapid reduction of the flue gas temperature by the liquid oxygen heater can inhibit the secondary generation of dioxins, further reducing the leaching of harmful substances such as dioxins.

[0033] Third, through the coordination of ultra-high temperature combustion environment and oxygen-rich combustion environment, the cyclone furnace forms an ultra-high temperature cyclone oxygen-rich combustion environment, which can deeply decompose dioxins, heavy metals and other stubborn pollutants produced during the combustion of coal and garbage, and significantly reduce their emissions.

[0034] Fourth, the oxygen-rich combustion environment increases the oxygen concentration during the combustion process, promotes the complete combustion of the fuel, and improves the combustion efficiency and power generation capacity. At the same time, the construction of high-temperature strong reduction in the combustion zone further optimizes the combustion process and improves the combustion efficiency of the fuel.

[0035] Fifth, by transporting the odor generated by domestic waste into the reduction zone in the cyclone furnace, the emissions of pollutants and odor in the traditional coal-fired power generation and domestic waste incineration processes are reduced, which has a significant effect on improving regional air quality and protecting the ecological environment, and is conducive to the realization of carbon emission reduction.

[0036] Sixth, by coupling the treatment of domestic waste, improving combustion efficiency and resource utilization of fly ash, the cost of fuel, waste and fly ash hazardous waste treatment is reduced, the overall economic benefits are improved, pollutant emissions are reduced, and the sustainable development of the industry is promoted.

[0037] Seventh, the system and method have strong adaptability and flexibility, and can be adjusted and optimized according to the garbage composition and coal characteristics of different regions to meet the actual needs of different regions. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0039] Figure 2a It is a schematic diagram of a first arrangement structure of multiple cyclone furnaces in the present invention;

[0040] Figure 2b It is a schematic diagram of a second arrangement structure of multiple cyclone furnaces in the present invention;

[0041] Figure 2c It is a schematic diagram of a third arrangement structure of multiple cyclone furnaces in the present invention;

[0042] Figure 3 It is a schematic diagram of the process flow of the present invention.

[0043] Reference numerals:

[0044] 1. Garbage storage pit; 2. Magnetic separator; 3. Crusher; 4. Screw feeder; 5. Feed and primary air inlet; 6. Cyclone furnace; 6-1. Combustion zone; 6-2. Reduction zone; 6-3. Burnout zone; 7. Pulverized coal burner; 8. Pure oxygen secondary air nozzle; 9. Fly ash return nozzle; 10. Recirculating flue gas nozzle; 11. Ball mill; 12. Odor nozzle; 13. Secondary air nozzle; 14. Burnout air nozzle; 15. Superheater and reheater; 16. Air preheater; 17. Liquid oxygen heater; 18. Electrostatic precipitator; 19. Denitrification device; 20. Desulfurization device; 21. Chimney; 22. Recirculation fan; 23. Odor fan; 24. Slag pool; 25. Air separation unit. DETAILED DESCRIPTION

[0045] The technical solution in the present application will be described clearly and in detail below in conjunction with the accompanying drawings. Among them, in the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, such as A and / or B, which can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" refers to two or more than two. The following terms "first" and "second" are used for descriptive purposes only and cannot be understood as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0046] like Figure 1As shown, the present invention provides a system for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment, including a cyclone furnace 6, an electrostatic precipitator 18 and a slag pool 24. The interior of the cyclone furnace 6 is divided into a combustion zone 6-1, a reduction zone 6-2 and a burnout zone 6-3 from its head to its tail. The cyclone furnace 6 is connected to a garbage feeding assembly and a coal powder feeding assembly near the combustion zone 6-1. The garbage feeding assembly is used to transport domestic garbage into the cyclone furnace 6. The coal powder feeding assembly is used to transport coal powder into the cyclone furnace 6 for combustion. The electrostatic precipitator 18 is connected to the cyclone furnace 6 near the burnout zone 6-3. A fly ash return nozzle 13 is provided on the cyclone furnace 6 near the combustion zone 6-1. The first outlet of the electrostatic precipitator 18 is connected to the fly ash return nozzle 13. The electrostatic precipitator 18 It is used to receive the high-temperature flue gas generated from the cyclone furnace 6 and remove the fly ash in the high-temperature flue gas, and then introduce the fly ash into the cyclone furnace 6 for high-temperature melting treatment. The slag pool 24 is connected to the reduction zone 6-2 inside the cyclone furnace 6. The slag pool 24 is used to cool and collect the liquid ash formed by the high-temperature melting treatment of the fly ash in the cyclone furnace 6, so as to realize the combination of high-temperature melting treatment of the fly ash and liquid slag discharge. By introducing the fly ash into the cyclone furnace 6 for high-temperature melting treatment, the liquid ash formed after the high-temperature melting treatment is discharged into the slag pool 24 for cooling and collection, thereby realizing the combination of high-temperature melting treatment of the fly ash and liquid slag discharge, reducing the leaching of harmful substances such as dioxins and heavy metals, reducing the treatment cost of hazardous waste fly ash, and realizing the closed-loop disposal of ash resources, thereby reducing the potential threat of fly ash to the environment.

[0047] like Figure 1 As shown, the second outlet of the electrostatic precipitator 18 is connected to the inlet of the denitrification device 19, the outlet of the denitrification device 19 is connected to the inlet of the desulfurization device 20, and the outlet of the desulfurization device 20 is connected to the inlet of the chimney 21. The flue gas after dust removal is denitrified and desulfurized by the denitrification device 19 and the desulfurization device 20 and then discharged through the chimney 21.

[0048] like Figure 1 As shown, the garbage feeding assembly includes a garbage storage pit 1, a magnetic separator 2, a crusher 3 and a screw feeder 4. The garbage storage pit 1 is used to store domestic garbage. The inlet of the magnetic separator 2 is connected to the first outlet of the garbage storage pit 1, the inlet of the crusher 3 is connected to the first outlet of the magnetic separator 2, the inlet of the screw feeder 4 is connected to the first outlet of the crusher 3, the head of the cyclone furnace 6 is provided with a feed and primary air port 5, the outlet of the screw feeder 4 is connected to the feed and primary air port 5, the domestic garbage is fermented and dehydrated in the garbage storage pit 1, the domestic garbage after fermentation and dehydration is successively passed through the magnetic separator 2 to remove metal substances, and is crushed by the crusher 3, and then is sent to the cyclone furnace 6 through the screw feeder 4. At the same time, the primary air enters the cyclone furnace 6 through the feed and primary air port 5 along with the domestic garbage.

[0049] like Figure 1As shown, an odor nozzle 12 is provided near the reduction zone 6-2 on the cyclone furnace 6, and the odor nozzle 12 is connected to the outlet of the odor blower 23, and the inlet of the odor blower 23 is respectively connected to the second outlet of the garbage storage pit 1, the second outlet of the magnetic separator 2, and the second outlet of the crusher 3. The odor generated by the domestic garbage in the garbage storage pit 1, the magnetic separator 2, and the crusher 3 is extracted and transported into the reduction zone in the cyclone furnace 6 for high-temperature harmless treatment, which reduces the emission of pollutants and odor in the traditional coal-fired power generation and garbage incineration process, plays a significant role in improving regional air quality and protecting the ecological environment, and is also conducive to achieving carbon emission reduction.

[0050] like Figure 1 As shown, the pulverized coal feeding assembly includes a steel ball mill 11 and a pulverized coal burner 7. The steel ball mill 11 is used to grind the coal entering therein to turn the coal into pulverized coal. The pulverized coal burner 7 is arranged on the cyclone furnace 6 near the combustion zone 6-1. The inlet of the pulverized coal burner 7 is connected to the outlet of the steel ball mill 11. The steel ball mill 11 is used to grind the coal entering therein to turn the coal into pulverized coal. The coal is fed into the steel ball mill 11 for grinding to obtain pulverized coal, and the pulverized coal is fed into the pulverized coal burner 7. The pulverized coal burner 7 ignites the pulverized coal and then feeds it into the cyclone furnace 6.

[0051] like Figure 1 As shown, a liquid oxygen heater 17 is arranged between the electrostatic precipitator 18 and the tail of the cyclone furnace 6, a first inlet of the liquid oxygen heater 17 is connected to a position of the cyclone furnace 6 near the burnout zone 6-3, a first outlet of the liquid oxygen heater 17 is connected to a first inlet of the electrostatic precipitator 18, a second inlet of the liquid oxygen heater 17 is connected to an air separation device 25, the air separation device 25 is used to produce liquid oxygen, a pure oxygen secondary air nozzle 8 is arranged on the cyclone furnace 6 near the combustion zone 6-1, a second outlet of the liquid oxygen heater 17 is connected to the pure oxygen secondary air nozzle 8, and the cyclone furnace 6 has a plurality of air outlets. The generated high-temperature flue gas enters the liquid oxygen heater 17 to exchange heat with liquid oxygen to heat the liquid oxygen, and then the heated liquid oxygen heater 17 is sent to the combustion zone 6-1 of the cyclone furnace 6, so that the combustion zone 6-1 of the cyclone furnace 6 forms an oxygen-rich combustion environment, blocking the generation of thermal NOx, avoiding the high-temperature environment in the cyclone furnace 6 to generate a large amount of NOx, reducing NOx emissions, and reducing environmental pollution. At the same time, quickly lowering the flue gas temperature through the liquid oxygen heater can inhibit the secondary generation of dioxins, further reducing the leaching of harmful substances such as dioxins.

[0052] like Figure 1As shown, a recirculating flue gas nozzle 10 and a secondary air nozzle 13 are provided near the reduction zone 6-2 on the cyclone furnace 6. The recirculating flue gas nozzle 10 is connected to the outlet of the recirculating fan 22. The inlet of the recirculating fan 22 is connected to the position near the burnout zone 6-3 in the cyclone furnace 6. The flue gas at the tail of the cyclone furnace 6 is sent back into the reduction zone 6-2 of the cyclone furnace 6 through the recirculating fan 22. At the same time, pure oxygen is sent in through the secondary air nozzle 13. The pure oxygen is mixed with the recirculated flue gas so that the oxygen concentration is higher than 30%, thereby improving the fuel burnout rate.

[0053] like Figure 1 As shown, a superheater and a reheater 15 are provided at the position of the burnout zone 6-3 in the cyclone furnace 6. The steam from the boiler is further heated by the superheater and the reheater 15, so that the steam becomes superheated steam, which is convenient for improving the thermoelectric conversion efficiency. An air preheater 16 is provided at the position between the tail and the superheater and the reheater 15 in the cyclone furnace 6. The air preheater 16 uses the high-temperature flue gas to preheat the flue gas entering the boiler. The position where the inlet of the recirculation fan 22 is connected to the cyclone furnace 6 is located between the superheater and the reheater 15 and the air preheater 16. A burnout air nozzle 14 is provided on the cyclone furnace 6 at the burnout zone 6-3.

[0054] like Figure 2a , 2b As shown in 2c, the present invention can arrange multiple horizontal cyclone furnaces 6 according to the heat capacity, multiple high-temperature horizontal cyclone furnaces 6 and a vertical flue connected together. In the present invention, a vertical cyclone furnace 6 can be used, and a slag capture pipe can be arranged in the flue connected to the vertical flue. In the present invention, multiple vertical cyclone furnaces 6 can be arranged according to the heat capacity, and multiple vertical cyclone furnaces 6 can be connected together to a vertical flue. In the present invention, multiple cyclone furnaces 6 can be arranged on one side or around the vertical flue according to the design. In the present invention, the recycled flue gas can be optionally sprayed into the high-temperature and highly reducing combustion zone 6-1 to increase the turbulence and flow rate in the cyclone furnace.

[0055] In the present invention, garbage and coal can be premixed in advance and then sprayed into the furnace through hot primary air.

[0056] In the present invention, the fly ash can be premixed with coal and then sprayed into the cyclone furnace 6.

[0057] In the present invention, a proper amount of reagent can be added to the slag to separate and recover high-value resources such as metals.

[0058] The system of the present invention can utilize the cold energy of liquid nitrogen in the air separation device according to the flue gas cooling demand.

[0059] In the present invention, the electrostatic precipitator 18 can be replaced by a bag filter or other types of precipitators.

[0060] The purified flue gas CO 2The content is as high as over 90%, and a capture device can be added after the purification device to achieve large-scale capture of CO2.

[0061] like Figure 3 As shown, the present invention also provides a method for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment, comprising the following steps:

[0062] The coal is fed into a steel ball mill 11 for grinding to obtain coal powder, and the coal powder is fed into a coal powder burner 7, through which an ultra-high temperature combustion environment is formed in the combustion zone 6-1 of the cyclone furnace 6;

[0063] Liquid oxygen is produced by using the air separation device 25, and the liquid oxygen enters the liquid oxygen heater 17. The high-temperature flue gas generated in the cyclone furnace 6 enters the liquid oxygen heater 17 to exchange heat with the liquid oxygen, and the liquid oxygen is heated to obtain heated liquid oxygen. The heated liquid oxygen is sent to the combustion zone 6-1 of the cyclone furnace 6, so that the combustion zone 6-1 of the cyclone furnace 6 forms an oxygen-rich combustion environment;

[0064] The domestic garbage is sent to the garbage storage pit 1 for storage, fermentation and dehydration. The domestic garbage after fermentation and dehydration is sequentially passed through the magnetic separator 2 to remove metal substances and the crusher 3 to obtain pre-treated domestic garbage. The pre-treated domestic garbage is sent to the feed and primary air inlet 5 through the screw feeder 4. The pre-treated domestic garbage enters the combustion zone 6-1 of the cyclone furnace 6 through the feed and primary air inlet 5. The pre-treated domestic garbage is burned in the ultra-high temperature combustion environment and oxygen-rich combustion environment of the combustion zone 6-1 to form liquid ash after combustion;

[0065] After the high-temperature flue gas comes out of the liquid oxygen heater 17, it enters the electrostatic precipitator 18, and the fly ash therein is filtered by the electrostatic precipitator 18. The fly ash enters the combustion zone 6-1 through the fly ash return nozzle 13 for high-temperature melting treatment; the liquid ash is introduced into the slag pool 24, and the liquid ash is cooled and collected.

[0066] Among them, the temperature of the ultra-high temperature combustion environment is 1600℃~2000℃, and the excess oxygen coefficient of the oxygen-rich combustion environment is 0.5~0.9.

[0067] Among them, the high-temperature flue gas is cooled from 490℃~510℃ to 190℃~210℃ after heat exchange with liquid oxygen, and the temperature of the liquid oxygen after heating is 100℃~200℃.

[0068] Among them, the particle size of pre-treated domestic waste is greater than or equal to 50mm, and the particle size of coal powder is less than 10mm.

[0069] Working principle: coal is fed into the steel ball mill 11 for grinding to obtain coal powder, so that the particle size of the coal powder is less than 10mm, and the coal powder is fed into the coal powder burner 7, through which an ultra-high temperature combustion environment is formed in the combustion zone 6-1 of the cyclone furnace 6, and the temperature is 1600℃~2000℃, and liquid oxygen is prepared by the air separation device 25. At the same time, the high-temperature flue gas generated in the cyclone furnace 6 enters the liquid oxygen heater 17 for heat exchange with the liquid oxygen, and the liquid oxygen is heated to 100℃~200℃ to obtain heated liquid oxygen, and the heated liquid oxygen heater 17 is fed into the combustion zone 6-1 of the cyclone furnace 6, so that the combustion zone 6-1 of the cyclone furnace 6 forms an oxygen-rich combustion environment, and the excess oxygen coefficient is 0.5~0.9, and the domestic garbage is fed into the garbage storage pit 1 for storage, fermentation and dehydration. The domestic garbage after fermentation and dehydration is successively After the metal substances are removed by the magnetic separator 2 and the waste is crushed by the crusher 3, the pretreated domestic waste is obtained so that the particle size of the pretreated domestic waste is greater than or equal to 50 mm. The pretreated domestic waste is fed into the feed and primary air inlet 5 through the screw feeder 4. The pretreated domestic waste enters the combustion zone 6-1 of the cyclone furnace 6 through the feed and primary air inlet 5. The pretreated domestic waste is burned in the ultra-high temperature combustion environment and the oxygen-rich combustion environment of the combustion zone 6-1. Liquid ash is formed after combustion. The ash is melted and vitrified at high temperature in the cyclone furnace 6. The ash is discharged in liquid form to the slag pool 24 for cooling and collection, so as to achieve harmless treatment of the ash. At the same time, the high-temperature flue gas comes out of the liquid oxygen heater 17 and enters the electrostatic precipitator 18. The fly ash therein is filtered by the electrostatic precipitator 18. The fly ash enters the combustion zone 6-1 through the fly ash return nozzle 13 for high-temperature melting treatment.

[0070] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A system for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment, comprising a cyclone furnace (6), wherein the interior of the cyclone furnace (6) is divided into a combustion zone (6-1), a reduction zone (6-2) and a burnout zone (6-3) from the head to the tail, and a garbage feeding assembly and a coal powder feeding assembly are connected to the cyclone furnace (6) near the combustion zone (6-1). It is characterized in that Also includes: An electrostatic precipitator (18) is connected to a position of the cyclone furnace (6) near the burnout zone (6-3); a fly ash return nozzle (13) is provided on the cyclone furnace (6) near the combustion zone (6-1); a first outlet of the electrostatic precipitator (18) is connected to the fly ash return nozzle (13); the electrostatic precipitator (18) is used to receive high-temperature flue gas generated in the cyclone furnace (6) and remove fly ash in the high-temperature flue gas, and then introduce the fly ash into the cyclone furnace (6) for high-temperature melting treatment; The slag pool (24) is connected to the reduction zone (6-2) inside the cyclone furnace (6) and is used to cool and collect liquid ash formed by high-temperature melting treatment of fly ash in the cyclone furnace (6), thereby realizing the combination of high-temperature melting treatment of fly ash and liquid slag discharge.

2. The system for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment according to claim 1, It is characterized in that A liquid oxygen heater (17) is provided between the electrostatic precipitator (18) and the tail of the cyclone furnace (6); a first inlet of the liquid oxygen heater (17) is connected to a position of the cyclone furnace (6) close to the burnout zone (6-3); a first outlet of the liquid oxygen heater (17) is connected to a first inlet of the electrostatic precipitator (18); a second inlet of the liquid oxygen heater (17) is connected to an air separation device (25); the air separation device (25) is used to produce liquid oxygen; a pure oxygen secondary air nozzle (8) is provided on the cyclone furnace (6) close to the combustion zone (6-1); and a second outlet of the liquid oxygen heater (17) is connected to the pure oxygen secondary air nozzle (8).

3. The system for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment according to claim 2, It is characterized in that The garbage feeding assembly comprises: A garbage storage pit (1) for storing domestic garbage; A magnetic separator (2), the inlet of which is connected to the first outlet of the garbage storage pit (1); A crusher (3), the inlet of which is connected to the first outlet of the magnetic separator (2); The inlet of the screw feeder (4) is connected to the first outlet of the crusher (3); the head of the cyclone furnace (6) is provided with a feed and primary air port (5); the outlet of the screw feeder (4) is connected to the feed and primary air port (5).

4. The system for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment according to claim 3, It is characterized in that The cyclone furnace (6) is provided with an odor nozzle (12) near the reduction zone (6-2), and the odor nozzle (12) is connected to the outlet of the odor blower (23), and the inlet of the odor blower (23) is respectively connected to the second outlet of the garbage storage pit (1), the second outlet of the magnetic separator (2), and the second outlet of the crusher (3).

5. The system for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment according to claim 3, It is characterized in that The pulverized coal feeding assembly comprises: A steel ball coal mill (11) is used to grind the coal entering therein to turn the coal into coal powder; A pulverized coal burner (7) is arranged on the cyclone furnace (6) near the combustion zone (6-1), and the inlet of the pulverized coal burner (7) is connected to the outlet of the steel ball coal mill (11).

6. A method for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment, It is characterized in that The system for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment according to claim 5 comprises the following steps: The coal is fed into a steel ball mill (11) for grinding to obtain coal powder, and the coal powder is fed into a coal powder burner (7), and the coal powder burner (7) forms an ultra-high temperature combustion environment in the combustion zone (6-1) of the cyclone furnace (6); Liquid oxygen is produced by using an air separation device (25), and the liquid oxygen enters a liquid oxygen heater (17). High-temperature flue gas generated in the cyclone furnace (6) enters the liquid oxygen heater (17) to exchange heat with the liquid oxygen, and the liquid oxygen is heated to obtain heated liquid oxygen. The heated liquid oxygen is sent to a combustion zone (6-1) of the cyclone furnace (6), so that the combustion zone (6-1) of the cyclone furnace (6) forms an oxygen-rich combustion environment; The domestic waste is sent to a waste storage pit (1) for storage, fermentation and dehydration. The domestic waste after fermentation and dehydration is sequentially passed through a magnetic separator (2) to remove metal substances and a crusher (3) to crush the domestic waste to obtain pre-treated domestic waste. The pre-treated domestic waste is sent to a feed and primary air inlet (5) through a screw feeder (4). The pre-treated domestic waste enters a combustion zone (6-1) of a cyclone furnace (6) through the feed and primary air inlet (5). The pre-treated domestic waste is burned in an ultra-high temperature combustion environment and an oxygen-rich combustion environment of the combustion zone (6-1), and liquid ash is formed after combustion. After the high-temperature flue gas comes out of the liquid oxygen heater (17), it enters the electrostatic precipitator (18), and the fly ash therein is filtered by the electrostatic precipitator (18). The fly ash enters the combustion zone (6-1) through the fly ash return nozzle (13) for high-temperature melting treatment; The liquid ash is introduced into a molten slag pool (24) to be cooled and collected.

7. The method for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment according to claim 6, It is characterized in that The temperature of the ultra-high temperature combustion environment is 1600° C. to 2000° C., and the excess oxygen coefficient of the oxygen-rich combustion environment is 0.5 to 0.

9.

8. The method for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment according to claim 6, It is characterized in that The high-temperature flue gas is cooled from 400°C to 600°C to below 200°C after heat exchange with liquid oxygen, and the temperature of the heated liquid oxygen is 100°C to 200°C.

9. The method for coal-fired coupled garbage cyclone oxygen-enriched combustion and fly ash melting treatment according to claim 6, It is characterized in that The particle size of the pretreated domestic waste is 5 mm to 50 mm, and the particle size of the coal powder is less than 0.1 mm to 10 mm.

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