A landfill leachate treatment system

Abstract

The application relates to a landfill waste percolate treatment system, which comprises a percolate collecting assembly and a waste incinerator, wherein a combustion zone is arranged in the hearth of the waste incinerator, a plurality of grates are distributed in the combustion zone at intervals, gaps between the grates are connected with air inlet pipes, one end of each air inlet pipe away from the waste incinerator is connected with a pressurized air supply unit, first atomizing nozzles are arranged in the air inlet pipes, the first atomizing nozzles are connected with the percolate collecting assembly through first flow adjusting pumps, the first flow adjusting pumps are opened to atomize the waste percolate through the nozzles and make the waste percolate enter the combustion zone along the ventilation air flow at a set flow, the waste percolate is fully dispersed along the air flow in the combustion zone and releases ammonia nitrogen under the action of high temperature in the hearth, the flue gas generated in the combustion zone is subjected to pre-denitration treatment, meanwhile, the aerosol formed by the waste percolate is cooled and cooled down to the grates by using the water evaporation when passing through the gaps between the grates, the maintenance cost is reduced, and the efficiency of waste incineration is improved.

Description

Technical Field

[0001] This application belongs to the field of landfill leachate treatment technology, and specifically relates to a landfill leachate treatment system. Background Technology

[0002] Currently, municipal solid waste is mainly treated through incineration and landfill. Incineration is suitable for high-temperature burning of dried waste. Its advantages are high waste treatment efficiency and low surface pollution. However, its disadvantages include high input costs and energy consumption, and the presence of large amounts of nitrogen monoxide and other waste gases in the flue gas, which causes air pollution and exacerbates the greenhouse effect. Landfilling involves anaerobic burial of waste by digging pits and covering the surface. The waste is fermented and degraded by microorganisms. Its advantages are low treatment costs and minimal losses. However, its disadvantages include slow processing time (usually several years) and the potential for some municipal solid waste (especially kitchen waste) to produce large amounts of leachate under pressure and rainfall. This leachate is rich in ammonia nitrogen, organic matter, and salts and heavy metals that are difficult to detect directly or indirectly. Once leaked onto the surface, it can easily cause serious pollution. Regarding incineration, existing technologies involve denitrification of the flue gas in the incinerator. Urea or other chemical denitrification agents are injected into the flue gas, and catalysts or high temperatures are used to decompose the agents into ammonia, which then reacts with nitric oxide. However, this requires a large amount of urea, increasing costs. Furthermore, patent CN109455884A discloses a nitrogen resource thermal extraction and recovery system. This system pre-treats landfill leachate to extract ammonia-containing wastewater, which is then used to generate ammonium bicarbonate solution, which is fed back into the tail gas recovery system of its ammonia absorption treatment unit to treat the emitted tail gas. This indicates that ammonia in landfill leachate can be used for denitrification. However, the ammonia nitrogen content in landfill leachate varies considerably, and high temperatures or catalysts are required for the denitrification reaction. Directly introducing this into the flue gas of a landfill incinerator is unlikely to achieve satisfactory results. Summary of the Invention

[0003] Based on the aforementioned technical needs, this application provides a landfill leachate treatment system that can improve the denitrification effect of landfill leachate on flue gas from landfill incinerators.

[0004] To achieve the above objectives, the technical solution of this application is as follows: A landfill leachate treatment system includes a landfill incinerator and a leachate collection assembly. The incinerator has a combustion zone inside its furnace, and several grates are spaced apart in the combustion zone. Air inlet pipes are connected to the gaps between the grates. Each end of the air inlet pipe away from the landfill incinerator is connected to a pressurized air supply unit. A first atomizing nozzle is installed inside the air inlet pipe, and each of the first atomizing nozzles is connected to the leachate collection assembly via a first flow regulating pump.

[0005] Preferably, the leachate collection assembly includes a landfill leachate tank, at least one long-term storage tank, and at least one near-expiration storage tank. The long-term storage tank and the near-expiration storage tank are respectively connected to the landfill leachate tank, and the first flow regulating pump is connected to at least one of the long-term storage tank and the near-expiration storage tank.

[0006] Preferably, the leachate collection assembly further includes an ultrafiltration unit and an emergency storage tank. The emergency storage tank is connected to the landfill leachate tank through the ultrafiltration unit, and the first flow regulating pump is connected to at least one of the long-term storage tank, the near-expiration storage tank, or the emergency storage tank.

[0007] Preferably, both the long-term storage tank and the near-expiration storage tank are equipped with auxiliary fermentation units.

[0008] Preferably, within the furnace of the waste incinerator, a permeate spraying zone and a urea spraying zone are arranged in a tiered manner along the flue gas discharge direction on one side of the combustion zone. The combustion zone is equipped with a first sensor for outputting the total amount of nitrogen monoxide. A second sensor is arranged between the urea spraying zone and the permeate spraying zone for outputting the remaining amount of nitrogen monoxide. The permeate spraying zone is equipped with several second atomizing nozzles, each connected to the permeate collection assembly via a second flow regulating pump. The urea spraying zone is equipped with several third atomizing nozzles, each connected to a urea storage tank via a third flow regulating pump.

[0009] Preferably, a plurality of auxiliary burners are provided at one end of the combustion zone adjacent to the permeate spray zone.

[0010] Preferably, a plurality of the second atomizing nozzles are evenly distributed around the inner wall of the permeate spraying zone.

[0011] Preferably, a plurality of the second atomizing nozzles are distributed in a tiered manner along the exhaust direction of the flue gas.

[0012] Preferably, a plurality of the third atomizing nozzles are evenly distributed around the inner wall of the urea spraying zone.

[0013] Preferably, the third atomizing nozzles are distributed in a tiered manner along the exhaust direction of the flue gas.

[0014] By adopting the above technical solution, compared with the prior art, this application has at least the following beneficial effects: During the process of supplying air to the furnace through the air inlet pipe to ignite the waste or increase the combustion temperature, the first flow regulating pump is turned on to atomize the leachate through the nozzles at a set flow rate and allow it to enter the combustion zone with the ventilation airflow. The leachate is fully dispersed in the large space of the combustion zone with the airflow and releases ammonia nitrogen under the high temperature of the furnace, thus performing pre-denitrification treatment on the flue gas generated in the combustion zone. At the same time, when the aerosol formed by the leachate passes through the grate gap, its moisture can be used to cool the grate through evaporation, extending the life of the metal grate in a high-temperature oxidizing environment, reducing maintenance costs, and improving the efficiency of waste incineration. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the landfill leachate treatment system in Example 1.

[0016] Figure 2 This is a schematic diagram of the landfill leachate treatment system in Example 2.

[0017] In the diagram: leachate collection assembly 10, waste infiltration tank 11, long-term storage tank 12, near-expiration storage tank 13, auxiliary fermentation unit 14, ultrafiltration unit 15, emergency storage tank 16, filter 17, waste incinerator 20, combustion zone 21, first sensor 211, air inlet pipe 212, first atomizing nozzle 213, first flow regulating pump 214, auxiliary burner 215, grate 216, leachate spraying zone 22, second atomizing nozzle 221, second flow regulating pump 222, urea spraying zone 23, third atomizing nozzle 231, third flow regulating pump 232, second sensor 233, urea storage tank 24, pressurized air supply unit 25. Detailed Implementation

[0018] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of this application will be further described below with reference to the accompanying drawings of the embodiments, and this application is not limited to the following specific implementation methods.

[0019] It should be understood that the same or similar reference numerals in the accompanying drawings of the embodiments correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "inner," "outer," "left," "right," "front," "rear," "top," and "bottom" indicate directions or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the structure or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms describing positional relationships in the accompanying drawings are for illustrative purposes only and should not be construed as limitations on this patent. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0020] The following is in conjunction with the appendix Figure 1 To be continued Figure 2 The present application will be further described in detail with reference to specific embodiments.

[0021] This application discloses a landfill leachate treatment system, including a leachate collection component 10 and a landfill incinerator 20. The leachate collection component 10 collects the leachate and performs pretreatment such as impurity removal and preliminary dehydration before storage. The incinerator 20 has a combustion zone 21 inside its furnace, connected to the waste inlet of the incinerator 20. This combustion zone 21 is mainly used for igniting and incinerating waste and is not only the area with the highest temperature inside the furnace (some power-generating incinerators can reach temperatures above 1000°C, such as mechanical grate incinerators and fluidized bed incinerators), but also the area where nitric oxide is concentrated. To improve the limiting effect of the combustion zone 21 on the nitric oxide content in the generated flue gas, in one embodiment... In the above-mentioned waste incinerator 20, a mechanical grate furnace is preferred. The furnace chamber of the mechanical grate furnace has rotatable grates 216 distributed along the combustion zone 21. The gaps between the grates 216 form air inlets. The grates 216 rotate so that the waste is burned and discharged from the furnace during the transfer process. Each air inlet forms multiple ventilation spaces between the grates 216 and is connected to several air inlet pipes 212. The air inlet pipes 212 are ventilation pipes that supply air to the waste incinerator 20. One end of the pipe is connected to a pressurized air supply unit 25 such as a blower and a compressor to supply oxygen to the incinerator so that the waste can be fully burned. A first atomizing nozzle 213 is provided in the air inlet pipe 212. The first atomizing nozzle 213 is connected to the permeate collection assembly 10 through a first flow regulating pump 214.

[0022] Using this system will have at least the following beneficial effects: During the process of supplying air to the furnace through the air inlet pipe 212 to ignite the waste or increase the combustion temperature, the first flow regulating pump 214 is turned on to atomize the leachate through the nozzles at a set flow rate and send it into the combustion zone 21 with the ventilation airflow. The leachate is fully dispersed in the large space of the combustion zone 21 with the airflow and releases ammonia nitrogen under the high temperature of the furnace, which pre-denitrifies the flue gas generated in the combustion zone 21. At the same time, when the aerosol formed by the leachate passes through the gap of the grate 216, its moisture can be used to cool the grate 216 through evaporation, which can extend the life of the metal grate 216 in the long-term high-temperature oxidation environment, reduce maintenance costs, and help improve the efficiency of waste incineration.

[0023] It should be noted that, due to the high temperature in the combustion zone 21, in order to avoid excessive ammonia nitrogen being oxidized into nitrous oxide at high temperatures and exacerbating the greenhouse effect, the spraying of leachate in the air inlet duct 212 should be carried out intermittently, and the flow rate and frequency should be strictly limited.

[0024] Based on the above embodiments, this application also provides some specific implementation methods to improve the above solutions.

[0025] Furthermore, the aforementioned leachate collection assembly 10 includes a landfill infiltration tank 11, at least one long-term storage tank 12, and at least one near-expiration storage tank 13. The long-term storage tank 12 and the near-expiration storage tank 13 are respectively connected to the landfill infiltration tank 11 via pipelines. A first flow regulating pump 214 is connected to at least one of the long-term storage tank 12 and the near-expiration storage tank 13. The landfill infiltration tank 11 is located below the area where landfills are collected, compressed, or landfilled, or connected to a landfill treatment tank (mainly used for treating domestic waste, such as kitchen waste). During the landfilling process, it collects the leachate generated by the landfill and performs preliminary filtration to increase the leachate concentration and prevent the leachate from flowing into the surface and causing pollution.

[0026] Specifically, the long-term storage tank 12 and the near-expiration storage tank 13 can be artificially constructed tank structures or manually openable or sealable tanks or other containers, such as anaerobic storage tanks. Filters 17 are installed on the connecting pipelines to the landfill infiltration tank 11 for coarse filtration. Reverse osmosis membranes and other technologies are used to further reduce the moisture content of the leachate and increase the concentration of the leachate in the storage tanks. Each storage tank is equipped with a leachate collection pump to provide a negative pressure environment, improving the collection efficiency of the landfill leachate and preventing pipeline blockage. In some embodiments, the landfill infiltration tank 11 is established based on a landfill recycling station in a certain area (urban area), and there can be more than one, with multiple interconnected areas allowed. The long-term storage tank 12 and the near-expiration storage tank... Multiple leachate pools 13 can be built around the landfill leachate pool 11. Among them, the long-term storage pool 12 can prioritize collecting leachate from landfilled waste that has been stored for a long time (such as waste that has been stored for a long time in some recycling stations due to limited landfill or incineration efficiency). This part of the leachate has a long natural fermentation time and sufficient oxidation, and can continue to be stored for a long time to significantly increase its ammonia nitrogen content. The near-expiration storage pool 13 can prioritize collecting leachate formed in a short time from waste with a short storage time and high water content. Although this part of the leachate has a short natural fermentation time and low ammonia nitrogen content, it is large in quantity and urgently needs to be diverted from the landfill leachate pool 11. However, after collection, anaerobic treatment or fermentation adjustment can also increase its ammonia nitrogen content in a short period of time.

[0027] By classifying and storing leachate according to storage duration and ammonia nitrogen concentration, the appropriate leachate can be sprayed onto the flue gas generated from waste incineration using atomized spraying based on the nitrogen monoxide content in the flue gas, and then denitrified at high temperature. This application not only rationally stores and consumes leachate, reducing the risk of leachate pollution of the ground and the risk of damage to incineration equipment due to excessive ammonia, but also provides a denitrification method and equipment structure for waste incinerators, which is beneficial to reducing the consumption of urea or other denitrification chemical products during the flue gas denitrification process.

[0028] Furthermore, in one embodiment, the leachate collection assembly 10 further includes an ultrafiltration unit 15 and an emergency storage tank 16. The specific structure of the emergency storage tank 16 can be referenced to the long-term storage tank 12 and the near-expiration storage tank 13. The emergency storage tank 16 is connected to the landfill leachate tank 11 via the ultrafiltration unit 15, and the first flow regulating pump 214 is connected to at least one of the long-term storage tank 12, the near-expiration storage tank 13, or the emergency storage tank 16. The ultrafiltration unit 15 further reduces the water content in the leachate through pressure differential, assisting the leachate entering the emergency storage tank 16 to rapidly increase the ammonia nitrogen concentration, so as to be used when the leachate in the long-term storage tank 12 is insufficient. In some embodiments, multiple emergency storage tanks 16 can also be arranged around the landfill leachate tank 11 to provide emergency treatment of the leachate when the landfill leachate tank 11, the long-term storage tank 12, and the near-expiration storage tank 13 are all overflowing. Due to the high maintenance cost of the ultrafiltration unit 15, the emergency reserve pool 16 is only activated as a backup solution for the above reasons. The water filtered by the ultrafiltration unit 15 has a low content of impurities and pollutants and can be directly used in irrigation, greening maintenance and other fields, or treated and returned to the urban water supply network to achieve the effect of energy conservation and emission reduction.

[0029] Furthermore, to accelerate the decomposition of organic nitrogen in the leachate and increase the ammonia nitrogen concentration, both the long-term storage tank 12 and the near-expiration storage tank 13 are equipped with auxiliary fermentation units 14. Specifically, in addition to removing impurities from the leachate, different auxiliary fermentation units 14 can independently or comprehensively provide a fermentation environment to increase the ammonia nitrogen generation rate. These auxiliary fermentation units 14 include, but are not limited to, one or more combinations of equipment such as anaerobic bacterial agent quantitative dosing devices, leachate stirring reactors, and storage container temperature regulating reactors to conduct auxiliary fermentation of the leachate in the tanks to different degrees, thereby increasing the ammonia nitrogen concentration of the leachate in different storage tanks to different levels based on ammonia nitrogen concentration requirements and cost requirements. In addition, to prevent large amounts of hazardous gases such as methane and hydrogen sulfide generated in the fermentation environment from entering the high-temperature environment of the furnace, gas collection and treatment devices are also required in the gas accumulation areas of the long-term storage tank 12, the near-expiration storage tank 13, and the leachate tank 11 to prevent the leakage of flammable and explosive gases and reduce the gas pressure in the storage tanks, facilitating the pumping out of the leachate.

[0030] In a preferred embodiment, in order to improve the denitrification effect, the furnace of the waste incinerator 20 is provided with a permeate spray zone 22 and a urea spray zone 23 arranged in a stepped manner on one side of the combustion zone 21 along the flue gas discharge direction. The combustion zone 21 is equipped with a first sensor 211, which includes an integrated nitric oxide concentration sensor. After high-temperature protection, it can monitor the concentration of nitric oxide in the flue gas generated in the combustion zone 21 and the flue gas flow rate in real time. The two are automatically multiplied under a corresponding program to obtain the total amount of nitric oxide (per unit time, such as per hour). The permeate spraying zone 22 is equipped with several second atomizing nozzles 221. In some different embodiments, the multiple second atomizing nozzles 221 can be evenly distributed around the circumference of the permeate spraying zone 22 to form a dense liquid mist network when spraying the permeate, thereby increasing the contact area between the permeate and the flue gas and improving the denitrification rate. Alternatively, multiple groups can be arranged in a tiered manner along the flue gas discharge direction in the permeate spraying zone 22, with each group of second atomizing nozzles 221 intermittently arranged along the flue gas flow direction. Spraying slows down the flue gas flow rate to prolong the denitrification process and reduces the risk of excessive ammonia nitrogen due to high temperature caused by excessive leachate concentration. The second atomizing nozzles 221 are connected to the long-term storage tank 12 and the near-term storage tank 13 through the second flow regulating pump 222. By installing solenoid valves on the connecting pipelines, the connection between the near-term storage tank 13 and the long-term storage tank 12 can be determined based on the total amount of nitrogen monoxide that needs to be denitrified. This allows leachate with different ammonia nitrogen concentrations to be fully atomized by the second atomizing nozzles 221 and sprayed into the flue gas. The high temperature and residual heat of the flue gas cause the ammonia nitrogen to react with the nitrogen monoxide, further denitrifying the flue gas and treating the leachate at the same time, avoiding its waste or pollution of the surface environment. The first flow regulating valve can adjust and set the supply flow rate of the leachate according to the total amount of nitrogen monoxide and the ammonia nitrogen concentration.

[0031] A second sensor 233 is installed between the urea spray zone 23 and the leachate spray zone 22. The arrangement of this second sensor 233 is similar to that of the first sensor 211 described above. It is used to obtain the residual nitrogen monoxide in the flue gas after leachate treatment. To reduce pollution caused by the emission of residual nitrogen monoxide into the atmosphere, several third atomizing nozzles 231 are installed in the urea spray zone 23. In a specific embodiment, the number, structure, and function of these third atomizing nozzles 231 are similar to those of the second atomizing nozzle 221 described above, and will not be repeated here. All third atomizing nozzles 231 are connected to the urea storage tank 24 via a third flow regulating pump 232. The urea storage tank 24 contains sufficient urea. The third flow regulating pump 232 can adjust the urea supply flow rate according to the ammonia nitrogen concentration and residual nitrogen monoxide in the urea, ensuring that the third atomizing nozzles 231 fully atomize the urea and spray it into the flue gas. This, combined with the leachate treatment, continuously denitrifies the flue gas, reducing nitrogen monoxide emissions. In other embodiments, the layout of the above-mentioned permeate spraying zone 22 and urea spraying zone 23 can be changed or adapted according to the structure of the incinerator, the temperature distribution of the furnace or the temperature distribution of the flue gas emission structure, so as to facilitate denitrification treatment.

[0032] Furthermore, in order to ensure that the leachate sprayed in the leachate spraying zone 22 can release ammonia and react fully with nitric oxide under high temperature conditions, thereby avoiding or reducing the cost of using catalysts, the temperature of the leachate spraying zone 22 should be within the range of 950℃±50℃.

[0033] To enable the permeate to efficiently form ammonia and react with nitric oxide and oxygen to produce nitrogen and water under catalyst-free conditions, this application simulated the reaction under high-temperature conditions and obtained the denitrification efficiency results corresponding to the effective temperature range as shown in the table below:

[0034] As shown in the table above, the efficiency of ammonia generation from permeate pyrolysis and the denitrification efficiency are expected to reach their optimal levels under catalytic-free conditions within a temperature range of 950℃±50℃. To avoid generating byproducts that reduce the denitrification effect, the permeate atomization flow rate should be strictly controlled to prevent excessively high ammonia nitrogen concentrations and excessively rapid pyrolysis due to high temperatures, which could lead to delayed reactions between ammonia and nitric oxide. For a conservative approach, the second flow regulating pump 222 should be started to spray the permeate when the temperature in the permeate spraying zone 22 reaches 950℃.

[0035] To ensure that the flue gas temperature in the permeate spray zone 22 can quickly reach 950℃ and to prevent rapid temperature loss during flue gas flow, several auxiliary burners 215 are installed at one end of the combustion zone 21 adjacent to the permeate spray zone 22. The auxiliary burners 215 include a pressurized gas supply system and an ignition system, which can increase the oxygen content in the flue gas and compensate for the temperature loss. Specifically, the auxiliary burners 215 can be evenly distributed around the top of the combustion zone 21 to increase the ignition area, or they can be distributed in a stepped manner along the flue gas discharge direction, referencing the distribution of each group of atomizing nozzles, to achieve continuous heating and prevent the flue gas from overheating, ensuring a suitable temperature for the denitrification reaction.

[0036] Finally, the temperature of the urea spray zone 23 is controlled within the range of 900℃±50℃. The reason is as follows: In the embodiment where the urea spray zone 23 is located above the leachate spray zone 22, referring to the temperature control range of the leachate spray zone 22 mentioned above, since urea has a lower water content and a higher ammonia nitrogen concentration (purer) than leachate, under the premise of fewer impurities, urea of ​​the same concentration is more likely to thermally decompose and release ammonia gas than leachate. Moreover, the temperature of the flue gas is slightly reduced (relatively reduced by 5% to 10%) when passing through the urea spray zone 23 compared to the leachate spray zone 22, resulting in a relatively lower flue gas flow rate, which makes it easier for ammonia gas to react with nitric oxide and achieve a higher reaction efficiency. Based on this, with reference to the optimal temperature of the permeate spray zone 22, the temperature of the urea spray zone 23 can be controlled to reach 900℃±50℃. Experiments show that when the ammonia nitrogen concentration is adjusted to the optimal parameters, the denitrification efficiency achieved by the rapid decomposition of urea into ammonia gas within this temperature range is up to 70%. Based on the denitrification effect already achieved by the permeate, further denitrification treatment of the flue gas using urea can make the overall denitrification efficiency no less than 90%.

[0037] Based on the above system, if applied properly, the following effects can be achieved: When the total amount of nitrogen monoxide in the flue gas produced by incinerating waste at different stages or from incinerating different types of waste changes, different types of leachate (with different storage periods) can be selected to perform preliminary denitrification of the flue gas. While treating a portion of the leachate, the ammonia content in the denitrification reaction can be controlled relatively precisely, avoiding excessive ammonia or the generation of large amounts of byproducts that would worsen the pollution of the flue gas. Furthermore, excessive leachate can be avoided from causing corrosion and blockage of the furnace body, nozzles, and other equipment due to excessive crystalline salts generated after evaporation. The system also utilizes urea for efficient denitrification of the remaining flue gas, consuming a large amount of nitrogen monoxide. This application aims to reduce the cost of urea use and the pollution risk of byproducts, and to maximize the utilization rate of leachate, truly aligning with the environmental protection concepts of energy conservation, emission reduction, and waste utilization.

Claims

1. A landfill leachate treatment system, comprising a landfill incinerator, characterized in that, It also includes a leachate collection component. The furnace of the waste incinerator is provided with a combustion zone. Several grates are distributed at intervals in the combustion zone. The gaps between the grates are connected to air inlet pipes. The end of the air inlet pipe away from the waste incinerator is connected to a pressurized air supply unit. A first atomizing nozzle is provided in the air inlet pipe. The first atomizing nozzle is connected to the leachate collection component through a first flow regulating pump.

2. The landfill leachate treatment system as described in claim 1, characterized in that, The leachate collection assembly includes a landfill leachate tank, at least one long-term storage tank, and at least one near-expiration storage tank. The long-term storage tank and the near-expiration storage tank are respectively connected to the landfill leachate tank, and the first flow regulating pump is connected to at least one of the long-term storage tank and the near-expiration storage tank.

3. The landfill leachate treatment system as described in claim 2, characterized in that, The leachate collection assembly further includes an ultrafiltration unit and an emergency storage tank. The emergency storage tank is connected to the landfill leachate tank through the ultrafiltration unit. The first flow regulating pump is connected to at least one of the long-term storage tank, the near-expiration storage tank, or the emergency storage tank.

4. The landfill leachate treatment system as described in claim 2, characterized in that, Both the long-term storage tank and the near-expiration storage tank are equipped with auxiliary fermentation units.

5. The landfill leachate treatment system as described in any one of claims 1 to 4, characterized in that, Inside the furnace of the waste incinerator, a permeate spray zone and a urea spray zone are arranged in a tiered manner along the flue gas discharge direction on one side of the combustion zone. A first sensor is installed in the combustion zone to output the total amount of nitrogen monoxide. A second sensor is installed between the urea spray zone and the permeate spray zone to output the residual amount of nitrogen monoxide. The permeate spray zone is equipped with several second atomizing nozzles, each of which is connected to the permeate collection assembly via a second flow regulating pump. The urea spray zone is equipped with several third atomizing nozzles, each of which is connected to a urea storage tank via a third flow regulating pump.

6. The landfill leachate treatment system as described in claim 5, characterized in that, Several auxiliary burners are provided at one end of the combustion zone adjacent to the permeate spray zone.

7. The landfill leachate treatment system as described in claim 5, characterized in that, Several second atomizing nozzles are evenly distributed around the inner wall of the permeate spraying zone.

8. The landfill leachate treatment system as described in claim 5, characterized in that, Several of the second atomizing nozzles are distributed in a tiered manner along the exhaust direction of the flue gas.

9. The landfill leachate treatment system as described in claim 5, characterized in that, Several of the third atomizing nozzles are evenly distributed around the inner wall of the urea spraying zone.

10. The landfill leachate treatment system as described in claim 5, characterized in that, Several of the third atomizing nozzles are distributed in a tiered manner along the exhaust direction of the flue gas.

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