Landfill leachate green low-carbon treatment device

Abstract

The invention discloses a green low-carbon treatment device for landfill leachate. The method belongs to the field of landfill leachate treatment. The problems of durability, biological accumulation and toxicity caused by the existing landfill leachate are solved. The device comprises a landfill leachate collecting tank, a three-dimensional electrolysis pretreatment tank, a sulfur circulation multi-stage anaerobic biological treatment tank, a sedimentation tank, an ozone catalysis device and a tail end biological enhancement filter tank which are connected in sequence. According to the invention, the removal of ammonia nitrogen, total phosphorus and refractory organic matters and the reduction of sludge in the biological treatment section are realized, and the effluent is ensured to reach the discharge standard in Pollution Control Standard for Household Refuse Landfill (GB 16889-2008). According to the invention, full quantification and low carbonization of landfill leachate treatment are realized, and the treatment cost is greatly reduced. According to the present invention, the environmental pollution problem can be easily solved, the water resource and the ecological environment can be protected, the technical progress and the industrial upgrading of the water treatment industry can be promoted, and the implementation of the green development and the sustainable development strategy can be promoted.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of landfill leachate treatment, and particularly relates to a green low-carbon landfill leachate treatment device. BACKGROUND

[0002] With the accelerated urbanization process in China, municipal solid waste treatment has become a key issue in ecological civilization construction. According to statistical data, the amount of municipal solid waste generated in large and medium-sized cities in China in 2019 has exceeded 235 million tons, and the amount of landfill leachate generated daily has reached 130-260 thousand tons. This complex wastewater with high toxicity and high pollution characteristics has become a major problem restricting environmental governance. The concentration of conventional pollutants such as COD and BOD in leachate is hundreds of times higher than that of municipal wastewater, and it is rich in toxic substances such as heavy metals and organic halides. The ammonia nitrogen content can reach 3000-5000 mg / L, and the characteristics of serious imbalance of carbon and nitrogen ratio greatly limit the efficiency of traditional biological denitrification process. Although the current mainstream "pretreatment-biochemical treatment-membrane separation" process can achieve standard discharge, the problems such as secondary pollution of membrane concentrate, rising operation cost caused by frequent membrane component pollution and the like are increasingly prominent. According to statistics, the maintenance cost of membrane system accounts for more than 40% of the total operation cost of the process, and the problem of concentrate treatment has not been fundamentally solved.

[0003] The technical bottlenecks such as insufficient denitrification efficiency (total nitrogen removal rate less than 70%), weak impact resistance of biochemical system (influent COD fluctuation amplitude more than 50%), and large amount of reagent consumption (ton of water treatment cost more than 50 yuan) commonly existing in the current process have made it difficult to meet the green development demand under the background of "double carbon". In particular, the concentrate produced in the membrane separation link is rich in refractory organic matter and heavy metal ions, and the treatment by evaporation crystallization or advanced oxidation will derive new environmental risks, so the end-of-pipe treatment dilemma needs to be radically innovated.

[0004] Under this background, the innovative integration of ozone catalytic oxidation and sulfur-circulating anaerobic ammonia oxidation process shows unique advantages. Ozone catalytic oxidation can strengthen the generation efficiency of hydroxyl radicals through heterogeneous catalysts, achieve efficient cracking of humic acid macromolecular organic matter in leachate, and effectively degrade biological inhibitors such as chlorinated organic matter with an oxidation potential of 2.8V, which can improve the BOD5 / COD ratio to more than 0.4, creating favorable conditions for subsequent biochemical treatment. The sulfur-circulating autotrophic denitrification technology breaks through the limitation of traditional heterotrophic denitrification on carbon source dependence, and uses sulfide as electron donor to reduce nitrate, and the recycling of elemental sulfur significantly improves the salt shock resistance of the system. The anaerobic ammonia oxidation bacteria group realizes the direct conversion path of NH 4+ -NO 2- , which saves 62.5% of oxygen consumption and 100% of carbon source demand compared with the traditional nitrification-denitrification process. This "waste treatment by waste" metabolic mechanism perfectly meets the low-carbon treatment demand.

[0005] The integrated process discards the design of the membrane separation unit, fundamentally avoids the secondary pollution problem of concentrated liquid, and realizes the resource conversion of pollutants by constructing a gradient metabolic network. The selective removal of toxic substances by front-end ozone catalysis and the formation of a sulfur-mediated electron transfer network form a synergistic effect, enabling the system to achieve high nitrogen removal efficiency (total nitrogen removal rate > 95%) and low carbon footprint (COD / NH 4+ -Under the condition of N fluctuation of 30%, the stable nitrogen removal efficiency (total nitrogen removal rate > 95%) is maintained. This technical innovation combining treatment performance and economy not only responds to the rigid requirements of full-amount leachate treatment, but also provides a feasible technical paradigm for the garbage treatment industry to achieve the "double carbon" goal. Its industrialization and popularization will restructure the leachate treatment technology pattern and promote the transformation and upgrading of environmental governance from passive response to active prevention. SUMMARY

[0006] The application aims to solve the problems of persistence, biological accumulation and toxicity caused by existing landfill leachate, and provides a landfill leachate green low-carbon treatment device.

[0007] A landfill leachate green low-carbon treatment device, which comprises landfill leachate collection tanks, three-dimensional electrolysis pretreatment tanks, sulfur cycle multi-stage anaerobic biological treatment tanks, sedimentation tanks, ozone catalysis devices and terminal biological reinforcement filter tanks connected in sequence.

[0008] The landfill leachate collection tank adopts an upper water inlet and lower water outlet mode; the three-dimensional electrolysis pretreatment tank adopts an upper water inlet and lower water outlet mode; the sulfur cycle multi-stage anaerobic biological treatment tank adopts an upper water inlet and upper water outlet mode; the sedimentation tank adopts an upper water inlet and upper water outlet mode and a bottom sludge discharge mode; the ozone catalysis device adopts a lower water inlet and upper water outlet mode; and the terminal biological reinforcement filter tank adopts a lower water inlet and upper water outlet mode.

[0009] Further, the three-dimensional electrolysis pretreatment tank comprises an anode electrode, a cathode electrode, a permeable membrane, a granular electrode, a nano aeration disc, a direct current stabilized power supply and a connecting wire; the anode electrode and the cathode electrode are crosswise and vertically placed in the three-dimensional electrolysis pretreatment tank, and the surfaces of the anode electrode and the cathode electrode are each covered with a layer of permeable membrane; the granular electrode is placed between the anode electrode and the cathode electrode; and the nano aeration disc is placed at the bottom of the three-dimensional electrolysis pretreatment tank.

[0010] Further, the three-dimensional electrolysis pretreatment tank is an organic glass container with a size of 50 cm in length, 30 cm in width and 60 cm in height.

[0011] The sizes of the anode electrode and the cathode electrode match the size of the three-dimensional electrolysis pretreatment tank.

[0012] The spacing between the anode electrode and the cathode electrode is 8 cm.

[0013] The material of the cathode electrode is titanium plate;

[0014] The applied current of the direct current stabilized power supply is 30 mA / cm 2 .

[0015] Further, the material of the anode electrode is Ti / RuO2 / IrO2-SnO2, and is made as follows:

[0016] Dissolve RuCl, H2IrCl (dichloride) and SnCl4 in 4 mL of anhydrous methanol to obtain a mixed solution, the molar ratio of Ru, Ir and Sn in the mixed solution is 5.5:1.0:3.9; add 1 mL of concentrated hydrochloric acid with a mass fraction of 36%-38% to the mixed solution and ultrasonic treat for 20 min to obtain a coating solution, then take 150 μL of the coating solution and uniformly brush it on the surface of the titanium substrate to obtain the anode electrode.

[0017] Further, the particle electrode is coconut shell biochar with a particle size of 1.7-2.36 mm; the addition amount of the particle electrode in the three-dimensional electrolytic pretreatment tank is 20 g / L, and the particle electrode is placed in the landfill leachate to be treated for supersaturation adsorption before addition.

[0018] Further, the working volume of the sulfur cycle multistage anaerobic biological treatment tank is 50 L, and is divided into five zones, namely, an anaerobic zone, a first anoxic zone, a first aerobic zone, a second anoxic zone and a second aerobic zone, and each zone is provided with sulfur cycle anaerobic sludge capable of stabilizing landfill leachate; a mechanical stirrer is arranged at the top of the anaerobic zone, the first anoxic zone and the second anoxic zone; and a sand bubble diffuser is arranged at the bottom of the first aerobic zone and the second aerobic zone.

[0019] Further, the water flow direction in the sulfur cycle multistage anaerobic biological treatment tank is from the bottom of the anaerobic zone to the bottom of the first anoxic zone, then from the upper part of the first anoxic zone to the upper part of the first aerobic zone, then from the bottom of the first aerobic zone to the bottom of the second anoxic zone, then from the upper part of the second anoxic zone to the upper part of the second aerobic zone, then from the bottom of the second aerobic zone back to the bottom of the first anoxic zone, the backflow ratio is 1:2, and the remaining part finally flows out of the second aerobic zone into the sedimentation tank.

[0020] Further, the sulfur cycle anaerobic sludge capable of stabilizing landfill leachate is prepared as follows:

[0021] a. Primary domestication:

[0022] The fresh sludge of the urban sewage treatment plant is taken as the inoculated sludge, placed in a sludge tank and added with a domestication agent, the domestication agent is above the fresh sludge, then the domestication agent is replaced every five days, after domestication for 10 days, the domesticated sulfur cycle anaerobic activated sludge is obtained, and then is respectively placed in five zones of the sulfur cycle multistage anaerobic biological treatment tank;

[0023] b, secondary domestication:

[0024] The leachate to be treated is taken as raw water and adjusted to pH 7-8, then is pumped into the anaerobic zone and the second anoxic zone of the sulfur cycle multistage anaerobic biological treatment tank, then the adding proportion of the raw water is gradually increased in the form of increasing concentration, the first stage water is the raw water diluted to 20%, the second stage water is the raw water diluted to 40%, the third stage water is the raw water diluted to 60%, the fourth stage water is the raw water diluted to 80%, and the fifth stage is the raw water, each stage is operated for 10-12 days, and the sulfur cycle anaerobic sludge capable of stably treating the leachate is obtained by domestication, and the particle size is 150-400 μm.

[0025] The domestication agent in step a contains 1 g of glucose, 1 g of sodium sulfate, 0.2 g of potassium dihydrogen phosphate, 0.2 g of magnesium sulfate, 0.5 g of calcium chloride and the rest of distilled water per liter of the domestication agent.

[0026] Further, the ozone catalytic device is an upflow ozone aeration device, ozone is continuously introduced at the bottom, and the ozone filler is filled in the device, and the filling rate is 60%.

[0027] The terminal biological enhanced filter tank comprises an aeration device and a combined filler, and the filling rate of the combined filler is 35%.

[0028] Further, the application method of the above garbage leachate green low-carbon treatment device is carried out according to the following process:

[0029] The landfill leachate to be treated flows out from the bottom of the landfill leachate collection tank and enters the three-dimensional electrolysis pretreatment tank in the up-flow mode, a direct current stabilizing power supply is started to carry out electrolysis treatment, the hydraulic retention time is 2-3h, then the effluent is pumped into the anaerobic zone and the second anoxic zone of the sulfur circulation multistage anaerobic biological treatment tank in the down-flow mode, the average influent quantity is 100L / d, the distribution of the anaerobic zone and the second anoxic zone accounts for 60% and 40% respectively, the total hydraulic retention time is 19.2h, the mechanical agitator and the sand bubble diffuser continuously work, the dissolved oxygen concentration of the first aerobic zone and the second aerobic zone is 5-6mg / L, then the effluent is flowed into the sedimentation tank in the up-flow mode, the sludge retention time is 16d, the sludge in the sedimentation tank is discharged every day and is refluxed to the anaerobic zone of the sulfur circulation multistage anaerobic biological treatment tank, the biological tail water in the sedimentation tank is pumped into the ozone catalysis device in the down-flow mode, the bottom continuously introduces ozone to carry out treatment, the hydraulic retention time is 8h, then the effluent is flowed into the terminal biological reinforced filter tank in the down-flow mode, the aeration device continuously works, the dissolved oxygen content in the water is controlled to be 2.0-7.0mg / L, the hydraulic retention time is 3-5h, the effluent reaches the discharge standard;

[0030] The total hydraulic retention time is 19.2h, wherein the hydraulic retention time of the anaerobic zone is 1.36h, the hydraulic retention time of the first anoxic zone is 3.06h, the hydraulic retention time of the first aerobic zone is 5.4h, the hydraulic retention time of the second anoxic zone is 3.74h, and the hydraulic retention time of the second aerobic zone is 5.64h;

[0031] The discharge standard is the discharge standard in the Standard for Pollution Control on Solid Waste Landfill Sites (GB 16889-2008). The present application has the following advantages:

[0032] The present application provides a new green and low-carbon treatment process for landfill leachate, which integrates three-dimensional electrolytic oxidation, ozone catalytic oxidation and sulfur circulation anaerobic ammonia oxidation and terminal guarantee treatment technology. The method can realize efficient removal of ammonia nitrogen, total phosphorus and refractory organic matter and sludge reduction in the biological treatment section through the combination of three-dimensional particle electrode material and special direct current electrolysis power supply to form catalytic particles for electrocatalytic oxidation and the sulfur circulation ammonia oxidation cycle formed by the domestication of sulfur electron acceptor. In order to ensure that the effluent meets the standard, an ozone catalysis device and a terminal biological reinforced filter tank are arranged at the rear end of the treatment to ensure that the treated effluent can meet the discharge standard in the Standard for Pollution Control on Solid Waste Landfill Sites (GB 16889-2008). The method provides an alternative solution for the treatment of landfill leachate in solid waste landfill sites.

[0033] The application significantly improves the treatment efficiency of landfill leachate and the effluent water quality. The three-dimensional electrolysis pretreatment technology effectively improves the biodegradability of the wastewater, and creates favorable conditions for subsequent biological treatment, aiming at the characteristics of high concentration and difficult degradation of landfill leachate. The anaerobic ammonia oxidation technology based on sulfur cycle further strengthens the denitrification and phosphorus removal effect, especially under the condition of high ammonia nitrogen and low C / N ratio, which reduces the treatment cost and improves the treatment efficiency. The ozone catalytic oxidation coupling technology carries out deep treatment on the refractory organic matter, and ensures that the effluent water quality meets the standard. The end guarantee treatment technology realizes the deep removal of pollutants such as suspended solids, total nitrogen and total phosphorus through the filtering device, and ensures that the final effluent meets the standard, solving the problems of persistence, biological accumulation and toxicity caused by existing landfill leachate.

[0034] At the same time, the application also realizes the full quantization and low carbonization of landfill leachate treatment. Compared with the traditional membrane treatment technology, the application avoids the generation of membrane concentrate and the problem of secondary treatment, realizes the full quantization treatment of leachate. At the same time, by optimizing the treatment process and parameters, the energy consumption and reagent consumption are reduced, and the greenhouse gas emission is reduced, which meets the development trend of low carbon and environmental protection. In addition, compared with the traditional landfill leachate treatment technology, the application greatly reduces the treatment cost through technical innovation and process optimization. The application helps to solve the problem of environmental pollution, protect water resources and ecological environment, and at the same time, promotes the technological progress and industrial upgrading of water treatment industry, and promotes the implementation of green development and sustainable development strategy.

[0035] The device of the application is suitable for green and low carbon treatment of landfill leachate. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 Figure 1 is a schematic diagram of the landfill leachate green and low carbon treatment device in the embodiment, wherein ① represents a landfill leachate collection tank, ② represents a three-dimensional electrolysis pretreatment tank, ③ represents a sulfur cycle multistage anaerobic biological treatment tank, ④ represents a sedimentation tank, ⑤ represents an ozone catalytic device, and ⑥ represents an end biological reinforcement filter tank. DETAILED DESCRIPTION

[0037] The technical scheme of the application is not limited to the following specific embodiments, and also includes any combination of the specific embodiments.

[0038] Specific embodiment one: the landfill leachate green and low carbon treatment device of the embodiment includes landfill leachate collection tank, three-dimensional electrolysis pretreatment tank, sulfur cycle multistage anaerobic biological treatment tank, sedimentation tank, ozone catalytic device and end biological reinforcement filter tank which are connected in sequence.

[0039] The landfill leachate collection tank adopts the mode of water inlet at the top and water outlet at the bottom; the three-dimensional electrolysis pretreatment tank adopts the mode of water inlet at the top and water outlet at the bottom; the sulfur circulation multistage anaerobic biological treatment tank adopts the mode of water inlet at the top and water outlet at the top; the sedimentation tank adopts the mode of water inlet at the top and water outlet at the top and sludge discharge at the bottom; the ozone catalysis device adopts the mode of water inlet at the bottom and water outlet at the top; and the terminal biological reinforcement filter tank adopts the mode of water inlet at the bottom and water outlet at the top.

[0040] In the embodiment, the landfill leachate collection tank stores landfill leachate as the influent.

[0041] Specific embodiment two: different from the specific embodiment one, the three-dimensional electrolysis pretreatment tank comprises an anode electrode, a cathode electrode, a permeable membrane, a granular electrode, a nano aeration disc, a direct current stabilized power supply and a connecting wire; the anode electrode and the cathode electrode are placed in the three-dimensional electrolysis pretreatment tank in a cross and vertical manner, and the surfaces of the anode electrode and the cathode electrode are both covered with a layer of permeable membrane; the granular electrode is placed between the anode electrode and the cathode electrode; and the nano aeration disc is placed at the bottom of the three-dimensional electrolysis pretreatment tank. The other steps and parameters are the same as those in the specific embodiment one.

[0042] In the embodiment, the purpose of covering the surfaces of the anode electrode and the cathode electrode with a layer of permeable membrane is to prevent excessive adsorption of pollutants on the electrode surface, thereby reducing the three-dimensional electrolysis catalytic effect.

[0043] In the embodiment, the three-dimensional electrolysis pretreatment tank introduces the granular electrode into the two-dimensional electrochemical system, and these granular electrodes act as microelectrodes and can be regarded as anodes or cathodes on different surfaces. These microelectrodes diffusing in the solution extend the reaction surface from the 2D electrode to the entire three-dimensional electrolysis pretreatment tank, thereby promoting mass transfer and electrocatalysis.

[0044] In the embodiment, the permeable membrane is a commercially available product.

[0045] Specific embodiment three: different from the specific embodiment two, the three-dimensional electrolysis pretreatment tank is an organic glass container, and the size of the three-dimensional electrolysis pretreatment tank is 50 cm in length, 30 cm in width and 60 cm in height.

[0046] The sizes of the anode electrode and the cathode electrode match the size of the three-dimensional electrolysis pretreatment tank.

[0047] The distance between the anode electrode and the cathode electrode is 8 cm.

[0048] The material of the cathode electrode is a titanium plate.

[0049] The applied current of the direct current stabilized power supply is 30 mA / cm 2 . The other steps and parameters are the same as those in the specific embodiment two.

[0050] Specific embodiment four: the difference between this embodiment and specific embodiment two is that the material of the anode electrode is Ti / RuO2 / IrO2-SnO2, which is made as follows:

[0051] Dissolve RuCl, H2IrCl and SnCl4 in 4 mL of anhydrous methanol to obtain a mixed solution, in which the molar ratio of Ru, Ir and Sn is 5.5:1.0:3.9; add 1 mL of 36%-38% concentrated hydrochloric acid to the mixed solution and ultrasonically treat for 20 min to obtain a coating solution, then take 150 μL of the coating solution and uniformly brush it on the surface of the titanium substrate to obtain an anode electrode. The other steps and parameters are the same as those in specific embodiment two.

[0052] Specific embodiment five: the difference between this embodiment and specific embodiment two is that the granular electrode is coconut shell biochar with a particle size of 1.7-2.36 mm; the addition amount of the granular electrode in the three-dimensional electrolysis pretreatment tank is 20 g / L, and the granular electrode is placed in the landfill leachate to be treated for supersaturation adsorption before addition. The other steps and parameters are the same as those in specific embodiment two.

[0053] In this embodiment, the coconut shell biochar is a commercially available product.

[0054] In this embodiment, the coconut shell biochar is a kind of abundant and easily available agricultural solid waste, and the use of coconut shell biochar as the granular electrode of the three-dimensional electrolysis pretreatment tank embodies the resource utilization.

[0055] Specific embodiment six: the difference between this embodiment and specific embodiment one is that the working volume of the sulfur cycle multistage anaerobic biological treatment tank is 50 L, and is divided into five zones, namely, an anaerobic zone, a first anoxic zone, a first aerobic zone, a second anoxic zone and a second aerobic zone, and each zone is provided with sulfur cycle anaerobic sludge capable of stabilizing landfill leachate; a mechanical stirrer is arranged at the top of the anaerobic zone, the first anoxic zone and the second anoxic zone; and a sand bubble diffuser is arranged at the bottom of the first aerobic zone and the second aerobic zone. The other steps and parameters are the same as those in specific embodiment one.

[0056] In this embodiment, the purpose of the mechanical stirrer is to maintain the suspension of the sulfur cycle anaerobic sludge capable of stabilizing landfill leachate; and the sand bubble diffuser serves as a gas supply and mixing device.

[0057] Specific embodiment seven: the difference between this embodiment and specific embodiment six is that the water flow direction in the sulfur cycle multistage anaerobic biological treatment tank is from the bottom of the anaerobic zone to the bottom of the first anoxic zone, then from the upper part of the first anoxic zone to the upper part of the first aerobic zone, then from the bottom of the first aerobic zone to the bottom of the second anoxic zone, then from the upper part of the second anoxic zone to the upper part of the second aerobic zone, and then from the bottom of the second aerobic zone to the bottom of the first anoxic zone, the reflux ratio is 1:2, and the remaining part is finally discharged from the upper part of the second aerobic zone into the sedimentation tank. The other steps and parameters are the same as those of specific embodiment six.

[0058] In this embodiment, the second aerobic zone is refluxed to the first anoxic zone, which aims to improve the removal effect of nutrients.

[0059] Specific embodiment eight: the difference between this embodiment and specific embodiment six is that the sulfur cycle anaerobic sludge capable of stably treating landfill leachate is prepared as follows:

[0060] a. Primary domestication:

[0061] Fresh sludge from a municipal wastewater treatment plant is used as inoculated sludge, placed in a sludge tank and inoculated with domestication agents, the domestication agents are above the fresh sludge, then the domestication agents are replaced every five days, after 10 days of domestication, the domesticated sulfur cycle anaerobic activated sludge is obtained, and then is respectively placed in the five zones of the sulfur cycle multistage anaerobic biological treatment tank;

[0062] b. Secondary domestication:

[0063] The landfill leachate to be treated is used as raw water and the pH is adjusted to 7-8, then pumped into the anaerobic zone and the second anoxic zone of the sulfur cycle multistage anaerobic biological treatment tank, and then gradually increase the proportion of raw water in a concentration increasing manner, the first stage is to dilute the raw water to 20%, the second stage is to dilute the raw water to 40%, the third stage is to dilute the raw water to 60%, the fourth stage is to dilute the raw water to 80%, and the fifth stage is the raw water, each stage runs for 10-12 days, and the sulfur cycle anaerobic sludge capable of stably treating landfill leachate is obtained after domestication, the particle size is 150-400 μm;

[0064] In step a, the domestication agent contains 1 g of glucose, 1 g of sodium sulfate, 0.2 g of potassium dihydrogen phosphate, 0.2 g of magnesium sulfate, 0.5 g of calcium chloride, and the rest is distilled water per liter of domestication agent. The other steps and parameters are the same as those of specific embodiment six.

[0065] This embodiment is the sludge domestication stage of the landfill leachate green low-carbon treatment device before normal operation, after obtaining the sulfur cycle anaerobic sludge capable of stably treating landfill leachate, the landfill leachate green low-carbon treatment device can be normally operated to treat the landfill leachate in batches.

[0066] Specific embodiment nine: the difference between this embodiment and specific embodiment one is that the ozone catalytic device is an upflow ozone aeration device, ozone is continuously introduced from the bottom, and the device is filled with ozone filler with a filling rate of 60%;

[0067] The terminal bioaugmented filter includes an aeration device and combined filler with a filling rate of 35%. Other steps and parameters are the same as those in specific embodiment one.

[0068] The ozone filler and the combined filler in this embodiment are commercially available products.

[0069] In this embodiment, the terminal bioaugmented filter needs to be biofilm formed by using conventional methods and aerobic activated sludge before normal operation, that is, the combined filler provides an attachment site for microorganisms, which facilitates the formation of a biofilm by microorganisms in the aerobic activated sludge and the stable formation of a biofilm, thereby effectively filtering and removing difficult-to-remove pollutants in water, completing bioaugmentation treatment, and further removing large particles of suspended solids and total nitrogen; the aerobic activated sludge is from the secondary sedimentation tank of a municipal wastewater treatment plant.

[0070] Specific embodiment ten: the difference between this embodiment and specific embodiment one is an application method of a garbage leachate green low-carbon treatment device, which is performed according to the following process:

[0071] The garbage leachate to be treated flows out from the bottom of the garbage leachate collection tank and flows into the three-dimensional electrolysis pretreatment tank in an upflow mode, a direct current stabilized power supply is started to perform electrolysis treatment, the hydraulic retention time is 2-3 h, and then the effluent is pumped into the anaerobic zone and the second anoxic zone of the sulfur circulation multistage anaerobic biological treatment tank in a downflow mode, the average inflow is 100 L / d, the anaerobic zone and the second anoxic zone are each allocated 60% and 40% of the total, the total hydraulic retention time is 19.2 h, the mechanical agitator and the sand bubble diffuser continuously work, the dissolved oxygen concentration in the first aerobic zone and the second aerobic zone is 5-6 mg / L, then the effluent is flowed into the sedimentation tank in an upflow mode, the sludge retention time is 16 d, the sedimentation tank discharges sludge every day and returns to the anaerobic zone of the sulfur circulation multistage anaerobic biological treatment tank, and the biological tail water in the sedimentation tank is pumped into the ozone catalytic device in an upflow mode, ozone is continuously introduced from the bottom for treatment, the hydraulic retention time is 8 h, then the effluent is flowed into the terminal bioaugmented filter in an upflow mode, the aeration device continuously works, the dissolved oxygen content in the water is controlled to be 2.0-7.0 mg / L, the hydraulic retention time is 3-5 h, and the effluent meets the discharge standard;

[0072] The total hydraulic retention time is 19.2h, wherein the hydraulic retention time of the anaerobic zone is 1.36h, the hydraulic retention time of the first anoxic zone is 3.06h, the hydraulic retention time of the first aerobic zone is 5.4h, the hydraulic retention time of the second anoxic zone is 3.74h, and the hydraulic retention time of the second aerobic zone is 5.64h;

[0073] The discharge standard is the discharge standard in the Standard for Pollution Control on Domestic Waste Landfill Sites (GB 16889-2008). The other steps and parameters are the same as in the first embodiment.

[0074] The beneficial effects of the present application are verified by the following examples:

[0075] The following description is only for the preferred embodiments of the present application and is not used to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or equivalently replace some technical features thereof, as long as the modifications, equivalent replacements, improvements, etc. are within the spirit and principle of the present application, which should be included in the protection scope of the present application.

[0076] Embodiment:

[0077] In combination with Figure 1 The application method of the garbage leachate green low-carbon treatment device shown in the figure is carried out according to the following process:

[0078] The garbage leachate to be treated flows out from the bottom of the garbage leachate collection tank and flows into the three-dimensional electrolysis pretreatment tank in the upflow mode, a direct current stabilized power supply is started to perform electrolysis treatment, the hydraulic retention time is 3h, and then the effluent is pumped into the anaerobic zone and the second anoxic zone of the sulfur circulation multi-stage anaerobic biological treatment tank in the upflow mode, the average inflow is 100L / d, the anaerobic zone and the second anoxic zone are distributed at 60% and 40% respectively, the total hydraulic retention time is 19.2h, the mechanical agitator and the sand bubble diffuser continuously work, the dissolved oxygen concentration of the first aerobic zone and the second aerobic zone is 6mg / L, and then the effluent flows into the sedimentation tank in the upflow mode, the sludge retention time is 16d, the sedimentation tank discharges sludge every day and returns to the anaerobic zone of the sulfur circulation multi-stage anaerobic biological treatment tank, the biological tail water in the sedimentation tank is pumped into the ozone catalytic device in the downflow mode, the bottom continuously introduces ozone for treatment, the hydraulic retention time is 8h, and then the effluent flows into the terminal biological enhanced filter tank in the downflow mode, the aeration device continuously works, the dissolved oxygen content in the water is controlled to be 5.0mg / L, the hydraulic retention time is 5h, and the effluent reaches the discharge standard;

[0079] The total hydraulic retention time is 19.2h, wherein the hydraulic retention time of the anaerobic zone is 1.36h, the hydraulic retention time of the first anoxic zone is 3.06h, the hydraulic retention time of the first aerobic zone is 5.4h, the hydraulic retention time of the second anoxic zone is 3.74h, and the hydraulic retention time of the second aerobic zone is 5.64h.

[0080] The effluent of the treated landfill leachate in the embodiment meets the discharge standard in the Standard for Pollution Control on Solid Waste Landfill Sites (GB 16889-2008).

Claims

1. A landfill leachate green low-carbon treatment device, characterized in that, It comprises a landfill leachate collection tank, a three-dimensional electrolysis pretreatment tank, a sulfur cycle multistage anaerobic biological treatment tank, a sedimentation tank, an ozone catalytic device and a terminal biological reinforced filter tank connected in sequence. The landfill leachate collection tank adopts an upper water inlet and lower water outlet mode; the three-dimensional electrolysis pretreatment tank adopts an upper water inlet and lower water outlet mode; the sulfur cycle multistage anaerobic biological treatment tank adopts an upper water inlet and upper water outlet mode; the sedimentation tank adopts an upper water inlet and upper water outlet and bottom sludge discharge mode; the ozone catalytic device adopts a lower water inlet and upper water outlet mode; and the terminal biological reinforced filter tank adopts a lower water inlet and upper water outlet mode. 2.The landfill leachate green low-carbon treatment device according to claim 1, characterized in that, The three-dimensional electrolysis pretreatment tank comprises an anode electrode, a cathode electrode, a permeable membrane, a granular electrode, a nano aeration disc, a direct current stabilized power supply and a connecting wire; the anode electrode and the cathode electrode are crosswise and vertically placed in the three-dimensional electrolysis pretreatment tank, and the surfaces of the anode electrode and the cathode electrode are each covered with a layer of permeable membrane; the granular electrode is placed between the anode electrode and the cathode electrode; and the nano aeration disc is placed at the bottom of the three-dimensional electrolysis pretreatment tank.

3. The green low-carbon landfill leachate treatment device according to claim 2, characterized in that, The three-dimensional electrolysis pretreatment tank is an organic glass container with a size of 50 cm in length, 30 cm in width and 60 cm in height. The sizes of the anode electrode and the cathode electrode match the size of the three-dimensional electrolysis pretreatment tank. The spacing between the anode electrode and the cathode electrode is 8 cm. The material of the cathode electrode is titanium plate. The direct current stabilized power supply has an applied current of 30 mA / cm 2 .

4. The green low-carbon landfill leachate treatment device according to claim 2, characterized in that, The material of the anode electrode is Ti / RuO2 / IrO2-SnO2, which is made as follows: RuCl, H2IrCl and SnCl4 are dissolved in 4 mL of anhydrous methanol to obtain a mixed solution, the molar ratio of Ru, Ir and Sn in the mixed solution being 5.5:1.0:3.9; 1 mL of concentrated hydrochloric acid with a mass fraction of 36%-38% is added to the mixed solution and ultrasonically treated for 20 min to obtain a coating solution, and then 150 μL of the coating solution is uniformly brushed on the surface of a titanium substrate to obtain the anode electrode.

5. The landfill leachate green low-carbon treatment device according to claim 2, characterized in that, The granular electrode is coconut shell biochar with a particle size of 1.7-2.36 mm; the addition amount of the granular electrode in the three-dimensional electrolysis pretreatment tank is 20 g / L, and the granular electrode is placed in the landfill leachate to be treated for supersaturation adsorption before being added. 6.The landfill leachate green low-carbon treatment device according to claim 1, characterized in that, The working volume of the sulfur cycle multistage anaerobic biological treatment tank is 50 L, and the tank is divided into five zones, namely, an anaerobic zone, a first anoxic zone, a first aerobic zone, a second anoxic zone and a second aerobic zone, and each zone is provided with sulfur cycle anaerobic sludge capable of stabilizing landfill leachate; a mechanical stirrer is arranged at the top of the anaerobic zone, the first anoxic zone and the second anoxic zone; and a sand bubble diffuser is arranged at the bottom of the first aerobic zone and the second aerobic zone.

7. The landfill leachate green low-carbon treatment device according to claim 6, characterized in that, In the sulfur cycle multistage anaerobic biological treatment tank, the water flow direction is from the bottom of the anaerobic zone to the bottom of the first anoxic zone, then from the upper part of the first anoxic zone to the upper part of the first aerobic zone, then from the bottom of the first aerobic zone to the bottom of the second anoxic zone, then from the upper part of the second anoxic zone to the upper part of the second aerobic zone, and then from the bottom of the second aerobic zone back to the bottom of the first anoxic zone, the backflow ratio being 1:2, and the remaining part finally flows out of the upper part of the second aerobic zone into the sedimentation tank. 8.The landfill leachate green low-carbon treatment device according to claim 6, characterized in that, The sulfur cycle anaerobic sludge capable of stably treating landfill leachate is prepared by the following process: a. Primary domestication: Fresh sludge from a municipal sewage treatment plant is used as inoculated sludge, which is placed in a sludge tank and added with domestication reagent. The domestication reagent is above the fresh sludge, and then the domestication reagent is replaced every five days. After domestication for 10 days, the domesticated sulfur cycle anaerobic active sludge is obtained, which is then placed in the five zones of the sulfur cycle multistage anaerobic biological treatment tank, respectively; b. Secondary domestication: The landfill leachate to be treated is used as raw water and adjusted to pH 7-8, and then pumped into the anaerobic zone and the second anoxic zone of the sulfur cycle multistage anaerobic biological treatment tank. The proportion of raw water is gradually increased in the form of increasing concentration. The first stage is to dilute the raw water to 20%, the second stage is to dilute the raw water to 40%, the third stage is to dilute the raw water to 60%, the fourth stage is to dilute the raw water to 80%, and the fifth stage is the raw water. Each stage is operated for 10-12 days. The domesticated sulfur cycle anaerobic sludge capable of stably treating landfill leachate is obtained, and the particle size is 150-400 μm. The domestication reagent in step a contains 1 g of glucose, 1 g of sodium sulfate, 0.2 g of potassium dihydrogen phosphate, 0.2 g of magnesium sulfate, 0.5 g of calcium chloride, and the rest is distilled water per liter of domestication reagent. 9.The landfill leachate green low-carbon treatment device according to claim 1, characterized in that, The ozone catalytic device is an upflow ozone aeration device, and ozone is continuously introduced at the bottom. The ozone filler is filled in the device, and the filling rate is 60%. The terminal biological enhanced filter tank includes an aeration device and a combined filler, and the filling rate of the combined filler is 35%. 10.The landfill leachate green low-carbon treatment device according to claim 1, characterized in that, The application method of the above-mentioned landfill leachate green low-carbon treatment device is carried out by the following process: The landfill leachate to be treated flows out from the bottom of the landfill leachate collection tank and flows into the three-dimensional electrolysis pretreatment tank in the upflow mode. The direct current stabilized power supply is started to perform electrolytic treatment, and the hydraulic retention time is 2-3 h. Then, the effluent is pumped into the anaerobic zone and the second anoxic zone of the sulfur cycle multistage anaerobic biological treatment tank in the downflow mode. The average inflow is 100 L / d, and the distribution of the anaerobic zone and the second anoxic zone is 60% and 40%, respectively. The total hydraulic retention time is 19.2 h. The mechanical agitator and the sand bubble diffuser work continuously. The dissolved oxygen concentration in the first aerobic zone and the second aerobic zone is 5-6 mg / L. Then, the effluent flows into the sedimentation tank in the upflow mode. The sludge retention time is 16 d. The sludge is discharged from the sedimentation tank every day and is returned to the anaerobic zone of the sulfur cycle multistage anaerobic biological treatment tank. The biological tail water in the sedimentation tank is pumped into the ozone catalytic device in the downflow mode. The bottom continuously introduces ozone for treatment. The hydraulic retention time is 8 h. Then, the effluent flows into the terminal biological enhanced filter tank in the downflow mode. The aeration device works continuously. The dissolved oxygen content in the water is controlled to be 2.0-7.0 mg / L. The hydraulic retention time is 3-5 h. The effluent meets the discharge standard. The total hydraulic retention time is 19.2h, wherein the hydraulic retention time of the anaerobic zone is 1.36h, the hydraulic retention time of the first anoxic zone is 3.06h, the hydraulic retention time of the first aerobic zone is 5.4h, the hydraulic retention time of the second anoxic zone is 3.74h, and the hydraulic retention time of the second aerobic zone is 5.64h. The discharge standard is the discharge standard in the Standard for Pollution Control on Solid Waste Landfill Sites (GB 16889-2008).

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