Landfill leachate electrochemical treatment device with low effluent biotoxicity

Abstract

The utility model discloses a landfill leachate electrochemical treatment device with low effluent biotoxicity, and belongs to the field of sewage treatment equipment. The device comprises an electrochemical treatment device, a power supply system, a dosing system and a tail gas absorption device. The electrochemical treatment device is of a double-layer cylindrical barrel structure composed of an inner insulating shell and an outer insulating shell, an electrocatalytic oxidation reaction zone is arranged between the two insulating shells, and a biotoxicity reduction reaction zone is arranged on the inner side of the inner insulating shell. Wastewater sequentially flows through the electrocatalytic oxidation reaction zone and the biotoxicity reduction reaction zone. Aiming at the characteristics of high salinity and poor biodegradability of the landfill leachate, the device realizes efficient carbon reduction through cooperation of adsorption and electro-catalysis, and meanwhile, aiming at generated toxic substances, the biotoxicity of effluent is reduced through medicament spraying, so that the effluent requirement is met. The device has the characteristics of high pollutant treatment efficiency, low effluent biotoxicity, low operation energy consumption and high automation degree, and has important significance in landfill leachate treatment scenes.

Description

Technical Field

[0001] The utility model belongs to the field of sewage treatment equipment, and in particular relates to an electrochemical treatment device for landfill leachate with low effluent biological toxicity. Background Art

[0002] Landfill leachate is a type of wastewater containing high concentrations of organic matter and ammonia nitrogen. It also features high salinity, poor biodegradability, and a complex pollutant composition. Improper leachate treatment can severely contaminate surface water, groundwater, and surrounding soil, posing a serious threat to the environment and human health. In recent decades, the electrocatalytic oxidation-biological system combined treatment process has been widely recommended as a post-treatment process for residual biodegradable pollutants in landfill leachate, tanning wastewater, printing and dyeing wastewater, and petrochemical wastewater.

[0003] Electrochemical treatment technology can utilize active species generated during the electrochemical process to treat macromolecular organic pollutants in landfill leachate, thereby improving the biodegradability of the wastewater and providing suitable water quality for subsequent biological treatment systems. However, during the electrochemical treatment process, high-salinity wastewater produces a series of toxic substances, represented by chlorinated byproducts, which are toxic to microorganisms and affect the effectiveness of the biological treatment system, thus limiting the engineering application of combined electrocatalytic oxidation and biological treatment processes. Therefore, it is of great significance to design an electrochemical treatment device that can reduce the biotoxicity of the effluent while maintaining electrochemical treatment efficiency. Utility Model Content

[0004] The purpose of the utility model is to overcome the defects of the prior art and provide a landfill leachate electrochemical treatment device with low effluent biological toxicity.

[0005] The specific technical solutions adopted in this utility model are as follows:

[0006] The utility model provides a landfill leachate electrochemical treatment device with low effluent biological toxicity, comprising an electrochemical treatment device, a power supply system, a dosing system and a tail gas absorption device;

[0007] The electrochemical treatment device is a double-layer cylindrical structure consisting of an inner and outer insulating shell. The electrocatalytic oxidation reaction zone is located between the two insulating shells, and the inner side of the inner insulating shell is the biotoxicity reduction reaction zone. The inner wall of the outer insulating shell and the outer wall of the inner insulating shell are respectively provided with an anode plate and a cathode plate. The anode plate and the cathode plate are respectively connected to the power supply system in a separately controlled manner.

[0008] A first water inlet pipe for receiving external wastewater is provided at the bottom of the electrocatalytic oxidation reaction zone; a plurality of particle electrodes are provided in the electrocatalytic oxidation reaction zone, and a plurality of detachable insulating support mesh plates for separating the particle electrodes are provided at intervals from top to bottom in the electrocatalytic oxidation reaction zone; the particle electrodes are spherical structures, including a particle electrode skeleton and a particle electrode filler; the particle electrode filler is placed in an insulating mesh bag and then in the particle electrode skeleton to form the particle electrode;

[0009] A second water inlet pipe is provided at the bottom of the electrocatalytic oxidation reaction zone, and the electrocatalytic oxidation reaction zone and the biological toxicity reduction reaction zone are connected through the second water inlet pipe; a water flow agitator is provided in the middle of the biological toxicity reduction reaction zone, and an aeration pipe connected to an external aerator is provided at the bottom; a water outlet pipe for discharging treated liquid is also provided at the bottom of the biological toxicity reduction reaction zone;

[0010] The electrocatalytic oxidation reaction zone and the biotoxicity reduction reaction zone are respectively provided with a water quality monitoring probe and a potential sensing probe; the power supply system includes a data transmission device, a current control device, and a power supply connected in sequence; the data transmission device receives the sewage water quality index in the electrocatalytic oxidation reaction zone monitored in real time by the water quality monitoring probe, and the chemical reaction potential in the biotoxicity reduction reaction zone monitored in real time by the potential sensing probe; the current control device adjusts the current output by the power supply in real time according to the sewage water quality index obtained by the data transmission device;

[0011] The dosing system includes a dosing control device, a drug storage tank, and a sprayer disposed in the biotoxicity reduction reaction zone; a valve is provided on the pipeline connecting the drug storage tank and the sprayer; the dosing control device adjusts the valve switch according to the chemical reaction potential obtained by the data transmission device;

[0012] The tail gas absorption device is communicated with the top of the electrochemical treatment device and is used for absorbing and purifying the acidic and toxic tail gas generated in the electrochemical treatment device.

[0013] Preferably, the particle electrode filler is a modified zeolite-activated carbon composite material with a particle size of 2 to 6 mm.

[0014] Preferably, a plurality of microporous aerators are evenly distributed on the aeration pipe.

[0015] Preferably, an insulating support mesh is horizontally fixed to the bottom of the biological toxicity reduction reaction zone, and both ends of the aeration pipe are fixed to the insulating support mesh through level adjusters to ensure that the aeration pipe is set horizontally.

[0016] Preferably, the anode plate is made of titanium plated with ruthenium and iridium; and the cathode plate is made of titanium or stainless steel.

[0017] Furthermore, the anode plate and the cathode plate are respectively provided with a titanium-copper composite material edging for achieving uniform current distribution.

[0018] Preferably, the water quality monitoring probe is arranged below the liquid surface of the electrocatalytic oxidation reaction zone to measure the chemical oxygen demand, ammonia nitrogen and total nitrogen water quality indicators of the electrocatalytic oxidation reaction zone.

[0019] Preferably, the insulating support mesh 7 can be made of polypropylene.

[0020] Preferably, the exhaust gas absorption device includes a ducted fan, an air inlet pipe, a circulating water tank, a circulating sprayer, and a packed tower; one end of the air inlet pipe is connected to the gas collecting top of the electrochemical treatment device, and the other end is connected to the packed tower through a pipeline provided with a ducted fan; a packed tower filler for absorbing exhaust gas is provided in the packed tower; a circulating sprayer is provided on the top of the packed tower, and the circulating liquid is absorbed by the circulating water tank and sprayed by the circulating sprayer.

[0021] Furthermore, an insulating support mesh is fixed in the middle of the packing tower, and the packing tower fillers are placed above the insulating support mesh and at the bottom of the packing tower, forming upper and lower packing layers; the packing tower fillers are made of polypropylene pall rings or Raschig rings.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) Through the setting of a double-layer cylindrical barrel structure, the electrocatalytic oxidation reaction zone and the biological toxicity reduction reaction zone are separated and connected, and the active species generated by the electrochemical process are used to treat the macromolecular organic pollutants in the landfill leachate, thereby improving the biodegradability of the wastewater. Subsequently, the biological toxicity of the wastewater is reduced by adding reagents, providing suitable water quality conditions for the subsequent wastewater to enter the biological treatment system. It is the first stage experimental device for the combined treatment of landfill leachate by the electrocatalytic oxidation-biological system.

[0024] (2) The insulating support mesh provides a limiting function for the particle electrodes, preventing them from entering the effluent and affecting the effluent water quality; the layout of the multi-layer insulating support mesh evenly distributes the particle electrodes in the electrocatalytic oxidation reaction zone, increasing the contact area between the wastewater and the particle electrode filler and improving the adsorption efficiency; the particle electrode filler is packaged in the particle electrode skeleton and placed on the insulating support mesh. This filling method is conducive to the replacement of the filler. The insulating support mesh and particle electrodes can be taken out regularly for cleaning and replacement, saving time and reducing the difficulty of replacement.

[0025] (3) Modified zeolite-activated carbon composite material is selected as particle electrode filler to form an adsorption-electrocatalytic oxidation system to improve mass transfer efficiency; compared with general particle electrode fillers, this composite material improves the conductivity of the particle electrode filler, reduces the internal resistance of the system, and saves operating energy consumption; at the same time, this composite material improves the specific adsorption capacity of pollutants in wastewater.

[0026] (4) A water flow agitator is provided in the middle of the biological toxicity reduction reaction zone, and a microporous aeration device is provided at the bottom; the water flow agitator plays a stirring role, which can fully mix the wastewater and the added reagents, so that the substances undergoing chemical reactions can reach the maximum contact and accelerate the reaction rate; the microporous aeration device continuously aerates the wastewater, which can increase the dissolved oxygen in the wastewater while causing the toxic gases dissolved in the wastewater to overflow through the tumbling and rising of the air in the wastewater.

[0027] (5) The wastewater quality and chemical reaction progress in the device are monitored in real time by the water quality monitoring probe and the potential sensing probe, and the data are transmitted to the current control device and the dosing control device through the data transmission device to achieve precise adjustment of the current and precise application of the drug, thereby avoiding waste of electricity and drugs.

[0028] (6) The tail gas absorption device of the present invention adopts the form of a packed tower to absorb the acidic and toxic gases produced by the electrocatalytic oxidation reaction for secondary utilization, thereby reducing the pollution of the electrochemical treatment device to the external environment and improving resource recycling; the layout of the ducted fan helps the flow of gas and prevents safety hazards such as explosion caused by local accumulation of gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is an overall schematic diagram of the electrochemical treatment device for landfill leachate with low effluent biotoxicity provided in this embodiment;

[0030] Figure 2 This is a top view of the electrochemical treatment device in this embodiment;

[0031] Figure 3 This is a schematic diagram of the water flow direction of the electrochemical treatment device in this embodiment;

[0032] Figure 4 Schematic diagram of the structure of the particle electrode in this embodiment;

[0033] In the figure: electrochemical treatment device 1; power supply system 2; dosing system 3; tail gas absorption device 4; anode plate 5; cathode plate 6; insulating support mesh plate 7; insulating shell 8; particle electrode 9; microporous aerator 10; aeration pipe 11; level regulator 12; aerator 13; water flow agitator 14; first water inlet pipe 15; second water inlet pipe 16; water outlet pipe 17; water quality monitoring probe 18; potential sensing probe 19; data transmission device 20; current control device 21; power supply 22; dosing control device 23; drug storage tank 24; valve 25; sprayer 26; duct fan 27; air inlet pipe 28; circulating water tank 29; circulating sprayer 30; packed tower filler 31; particle electrode skeleton 32; particle electrode filler 33. DETAILED DESCRIPTION

[0034] The present invention will be further described and illustrated below in conjunction with the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly without conflict.

[0035] like Figure 1 As shown, as a preferred embodiment of the present invention, this embodiment provides an electrochemical treatment device for landfill leachate with low effluent biotoxicity. The device comprises an electrochemical treatment device 1, a power supply system 2, a dosing system 3, and an exhaust gas absorption device 4. The power supply system 2, dosing system 3, and exhaust gas absorption device 4 are all connected to the electrochemical treatment device 1, and the housings of all devices are insulated to ensure safe use.

[0036] like Figure 2 As shown, the electrochemical treatment device 1 provided by the present invention comprises a double-layer cylindrical structure consisting of an inner and outer insulating shell 8. The electrocatalytic oxidation reaction zone is located between the two insulating shells 8, and the biotoxicity reduction reaction zone is located within the inner insulating shell 8. An anode plate 5 and a cathode plate 6 are provided on the inner and outer walls of the outer and inner insulating shells 8, respectively. The electrocatalytic oxidation reaction zone, which has a circular cross-section, is formed between the anode plate 5 and the cathode plate 6.

[0037] In this embodiment, the anode plate 5 is made of titanium-plated ruthenium-iridium material, and the cathode plate 6 is made of titanium or stainless steel. The anode plate 5 and the cathode plate 6 are each connected to the power supply system 2 in a separately controlled manner. The power supply system 2 includes a data transmission device 20, a current control device 21, and a power supply 22, which are connected in sequence. The anode plate 5 is connected to the positive electrode of the power supply 22 via a cable, and the cathode plate 6 is connected to the negative electrode of the power supply 22 via a cable. At the same time, the tops of the anode plate 5 and the cathode plate 6 are both edged with a titanium-copper composite material to ensure that the current flows evenly throughout the entire electrode.

[0038] like Figure 3As shown, a first water inlet pipe 15 for receiving external wastewater is provided at the bottom of the electrocatalytic oxidation reaction zone. A plurality of particle electrodes 9 are provided in the electrocatalytic oxidation reaction zone, and a plurality of detachable insulating support meshes 7 are arranged at intervals from top to bottom in the electrocatalytic oxidation reaction zone. The insulating support meshes 7 are used to separate the particle electrodes 9 in the electrocatalytic oxidation reaction zone. The size of the gaps on the insulating support meshes 7 is smaller than the size of the particle electrodes 9. The insulating support meshes 7 allow water to pass through, but block and limit the particle electrodes 9. Combined with the flow of water, the particle electrodes 9 form a fluidized bed that fills the entire reaction tank. The insulating support meshes 7 can be made of polypropylene to avoid short circuits in the reaction tank.

[0039] The particle electrode 9 provided in this embodiment is a spherical structure, including a particle electrode skeleton 32 and a particle electrode filler 33. The particle electrode filler 33 is placed in an insulating mesh bag and then placed in the particle electrode skeleton 32 to form the particle electrode 9. Figure 4 This design prevents the particle electrode 9 from directly contacting the anode plate 5 and the cathode plate 6. In this embodiment, the particle electrode filler 33 is a modified zeolite-activated carbon composite material with a particle size of 2 to 6 mm.

[0040] In this embodiment, the preparation method of the modified zeolite-activated carbon composite material is as follows: commercial activated carbon is soaked in a 1 mol / L urea solution at room temperature for 2 hours. After removing water, the resulting material is calcined at 450°C for 50 minutes under an N2 environment, and then mixed with commercial zeolite and sodium hydroxide, suspended in deionized water and aged for 12 hours, and then heated to 80-120°C and kept warm for 8 hours. After filtering the product, it is continuously washed with deionized water and finally dried at 110°C to obtain a modified zeolite-activated carbon composite material.

[0041] A second water inlet pipe 16 is provided at the bottom of the electrocatalytic oxidation reaction zone, and the electrocatalytic oxidation reaction zone and the biological toxicity reduction reaction zone are connected through the second water inlet pipe 16. A water outlet pipe 17 for discharging the treated liquid is also provided at the bottom of the biological toxicity reduction reaction zone. Figure 3 As shown, wastewater enters the bottom of the electrocatalytic oxidation reaction zone through a first water inlet pipe 15, then flows upward to undergo the electrocatalytic oxidation reaction. After the reaction is complete, it enters the biotoxicity reduction reaction zone through a second water inlet pipe 16. Finally, the post-reaction liquid flows out through an outlet pipe 17.

[0042] A water flow agitator 14 is provided in the middle of the biotoxicity reduction reaction zone, and an aeration pipe 11 connected to an external aerator 13 is provided at the bottom. In this embodiment, an insulating support mesh 7 is fixed horizontally at the bottom of the biotoxicity reduction reaction zone, and both ends of the aeration pipe 11 are fixed to the insulating support mesh 7 via level adjusters 12 to ensure that the aeration pipe 11 is arranged horizontally. Figure 2As shown, a plurality of microporous aerators 10 are evenly distributed on the aeration pipe 11. The microporous aerators 10 continuously aerate the wastewater, which can increase the dissolved oxygen in the wastewater and at the same time make the toxic gases dissolved in the wastewater overflow through the tumbling and rising of the air in the wastewater.

[0043] In practical applications, wastewater first flows through the electrocatalytic oxidation reaction zone of the electrochemical treatment device 1. This zone comprises a three-dimensional electrochemical reaction cell, combining adsorption and electrocatalytic oxidation, and is comprised of an anode plate 5, a cathode plate 6, and a particle electrode 9. While the particle electrode filler 33 adsorbs pollutants in the wastewater, the titanium-plated ruthenium-iridium anode plate 5, with its strong chlorine-evolving properties, degrades nitrogen pollutants and oxidizes macromolecular, non-biodegradable organic pollutants, improving the biodegradability of the wastewater. The wastewater then enters the biotoxicity reduction reaction zone, where a reagent mixes and reacts with toxic substances in the wastewater. This reaction is then fully achieved through the action of the water flow agitator 14 and microporous aerator 10.

[0044] like Figure 1 As shown, a water quality monitoring probe 18 and a potential sensing probe 19 are respectively installed in the electrocatalytic oxidation reaction zone and the biotoxicity reduction reaction zone. The water quality monitoring probe 18 is located below the liquid surface in the electrocatalytic oxidation reaction zone and is used to measure water quality indicators such as chemical oxygen demand, ammonia nitrogen, and total nitrogen in the electrocatalytic oxidation reaction zone. The potential sensing probe 19 extends below the liquid surface in the biotoxicity reduction reaction zone and is used to measure the chemical reaction potential in the biotoxicity reduction reaction zone.

[0045] The data transmission device 20 receives real-time data on wastewater quality within the electrocatalytic oxidation reaction zone, as monitored by the water quality monitoring probe 18, and the chemical reaction potential within the biotoxicity reduction reaction zone, as monitored by the potential sensing probe 19. The current control device 21 adjusts the current output by the power supply 22 in real time based on the wastewater quality data obtained by the data transmission device 20. Specifically, the current control device 21 automatically adjusts the current based on the target pollutant concentration and the biodegradability of the effluent, avoiding issues such as excess energy and low removal efficiency caused by excessively high or low current.

[0046] Specifically, the power supply system 2 is connected to the anode plate 5 and the cathode plate 6 through cables, and is in a constant current power supply mode. The current density can be set to 5-30 mA / cm 2 Depending on the current applied, the cable can be 150 to 300 mm 2Single-core flexible cable prevents overheating caused by high current. In practical applications, wastewater should be introduced first. After the water quality monitoring probe 18 is functioning normally, power supply 22 should be connected. Then, the data transmission device 20 and current control device 21 should be activated for automatic control. Before shutting down the electrochemical treatment device 1 for maintenance, the data transmission device 20 and current control device 21 should be shut down, followed by power supply 22. Finally, all wastewater should be drained.

[0047] In this embodiment, the dosing system 3 includes a dosing control device 23, a drug storage tank 24, and a sprinkler 26 disposed in the biotoxicity reduction reaction zone. A valve 25 is provided on the pipeline connecting the drug storage tank 24 and the sprinkler 26. The drug dosing control device 23 adjusts the opening and closing of the valve 25 based on the chemical reaction potential obtained by the data transmission device 20. Specifically, the drug dosing control device 23 uses the potential mutation signal as a sign of the completion of the chemical reaction and automatically controls the opening and closing state of the valve 25 of the drug storage tank 24 to avoid problems such as waste of drug or incomplete removal of toxic substances due to excessive or insufficient dosage. The drug storage tank 24 stores a drug for reducing the biotoxicity of the effluent from the electrocatalytic oxidation reaction zone. The tank in the drug storage tank 24 has upper and lower limits engraved on it. If insufficient, it should be replenished promptly. The opening and closing of the water outlet pipe of the drug storage tank 24 is controlled by the valve 25. The drug enters the biotoxicity reduction reaction zone through the sprinkler 26 and reacts with the effluent from the electrocatalytic oxidation reaction zone.

[0048] It should be noted that the type and concentration of the reagent stored in the reagent storage tank 24 are selected according to the quality of the wastewater. In this embodiment, hydrogen peroxide solution can be used.

[0049] In actual use, wastewater should be introduced first. After the potential sensing probe 19 is functioning properly, valve 25 should be opened, followed by the data transmission device 20 and the dosing control device 23 for automatic dosing. Before shutting down the electrochemical treatment device 1 for maintenance, the data transmission device 20 and the dosing control device 23 should be shut down, followed by valve 25, and finally, all wastewater should be drained.

[0050] This embodiment is also provided with a tail gas absorption device 4 for absorbing and purifying the acidic and toxic tail gas generated in the electrochemical treatment device 1. The tail gas absorption device 4 includes a ducted fan 27, an air inlet pipe 28, a circulating water tank 29, a circulating sprayer 30, and a packing tower. One end of the air inlet pipe 28 is connected to the gas collecting top of the electrochemical treatment device 1, and the other end is connected through a ducted packing tower provided with a ducted fan 27. A packing tower packing 31 for absorbing tail gas is provided in the packing tower. A circulating sprayer 30 is provided at the top of the packing tower, and the circulating sprayer 30 absorbs the circulating liquid from the circulating water tank 29 and sprays it. An insulating support mesh 7 is fixed in the middle of the packing tower, and the packing tower packing 31 is placed above the insulating support mesh 7 and at the bottom of the packing tower, respectively, to form two upper and lower packing layers.

[0051] In actual application, a gas collection area must be set above the electrochemical treatment device 1. After the gas is collected, it enters the tail gas absorption device 4 through the air inlet pipe 28. The air inlet pipe 28 is connected to the top of the gas collection of the electrochemical treatment device 1, and the pipe diameter can be set to 80-150mm. The duct fan 27 is located in the air inlet pipe 28, and the air volume can be selected from 100 to 500m 3 / h. The packing 31 of the packed tower can be made of polypropylene ball rings or Raschig rings with a specification of 25 to 38 mm. A circulating sprayer 30 is provided on the top of the packed tower, which absorbs and sprays the liquid from the circulating water tank 29. The liquid in the circulating water tank 29 is a sodium hydroxide solution with a concentration of 10% to 15%. During actual operation, the circulating sprayer 30 should be opened first, and then the air volume of the ducted fan 27 should be slowly adjusted to prevent liquid flooding. After the adjustment is stable, the electrochemical treatment device 1 can be started. Before the electrochemical treatment device 1 is shut down for maintenance, it is necessary to first shut down the electrochemical treatment device 1, drain all the wastewater, and then run it for 10 to 30 minutes to ensure that all toxic gases are safely recovered. Then, the ducted fan 27 and the circulating sprayer 30 should be shut down in sequence.

[0052] The above electrochemical treatment device is used to treat landfill leachate containing high concentrations of difficult-to-biodegrade organic matter. The specific treatment method is as follows:

[0053] First, ensure that the power supply system 2, dosing system 3, and exhaust gas absorption device 4 are properly connected to the electrochemical treatment device 1, operating normally, and properly insulated. Turn on the circulation sprayer 30 of the exhaust gas absorption device 4, then turn on the ducted fan 27 and slowly adjust the air volume to prevent flooding. Once the adjustment stabilizes, maintain operation.

[0054] Close the second water inlet pipe 16 and the water outlet pipe 17, and pass the wastewater to be treated into the electrochemical treatment device 1 through the first water inlet pipe 15. After the wastewater fills the entire electrocatalytic oxidation reaction zone, immerse the water quality monitoring probe 18 below the liquid surface and begin real-time monitoring of water quality information. After the water quality data is basically stable, turn on the power supply 22, and then turn on the data transmission device 20 and the current control device 21 for automatic regulation. After the biodegradability of the wastewater meets the standard, open the second water inlet pipe 16, and the wastewater enters the biological toxicity reduction reaction zone. Immerse the potential sensing probe 19 below the liquid surface, open the valve 25, and then turn on the dosing control device 23 for automatic dosing. After the chemical reaction is completed, open the water outlet pipe 17, and the wastewater flows out of the electrochemical treatment device 1.

[0055] The above is the operating method for the initial operation of the electrochemical treatment device 1. The first water inlet pipe 15 and the second water inlet pipe 16 need to be opened step by step. After stable operation, the water inlet pipes can be continuously connected, the continuous flow operation mode can be turned on, and water can be in and out synchronously. If you want to stop the operation or perform maintenance, you must first stop the water supply, turn off the current control device 21, and then slowly reduce the current. Then, turn off the power supply 22. After the remaining wastewater has completed the reaction in the biological toxicity reduction reaction zone, turn off the dosing control device 23, then close the valve 25, drain all the wastewater, and then operate the tail gas absorption device 4 for 10 to 30 minutes. After ensuring that all toxic gases are safely absorbed, turn off the duct fan 27 and the circulating sprinkler 30 in sequence. After closing all devices, you can stop the operation or perform maintenance.

[0056] This utility model addresses the high salinity, poor biodegradability, and high biotoxicity of landfill leachate. By designing a double-layer cylindrical structure, this device combines electrocatalytic oxidation and biotoxicity reduction reactions within a single electrochemical treatment device. This device can degrade recalcitrant organic matter in landfill leachate, improving its biodegradability and reducing its biotoxicity through the addition of reagents. It also balances tail gas absorption with energy recovery. It boasts a small footprint, highly targeted pollutant degradation, minimal secondary pollution, and a high degree of automation. Compared to traditional electrochemical processes, it offers advantages such as reduced operating energy consumption, reduced effluent biotoxicity, and the ability to be coupled with biological treatment processes.

[0057] The above embodiment is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Persons skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent substitution or equivalent transformation falls within the scope of protection of the present invention.

Claims

1. An electrochemical treatment device for landfill leachate with low effluent biotoxicity, characterized in that: It comprises an electrochemical treatment device (1), a power supply system (2), a dosing system (3) and a tail gas absorption device (4); The electrochemical treatment device (1) is a double-layer cylindrical barrel structure consisting of an inner and outer insulating shell (8); the electrocatalytic oxidation reaction zone is located between the two insulating shells (8); the inner side of the inner insulating shell (8) is a biological toxicity reduction reaction zone; the inner wall of the outer insulating shell (8) and the outer wall of the inner insulating shell (8) are respectively provided with an anode plate (5) and a cathode plate (6); the anode plate (5) and the cathode plate (6) are respectively connected to the power supply system (2) in a separately controlled manner; A first water inlet pipe (15) for receiving external wastewater is provided at the bottom of the electrocatalytic oxidation reaction zone; a plurality of particle electrodes (9) are provided in the electrocatalytic oxidation reaction zone, and a plurality of detachable insulating support mesh plates (7) for separating the particle electrodes (9) are provided at intervals from top to bottom in the electrocatalytic oxidation reaction zone; the particle electrodes (9) are spherical structures, including a particle electrode skeleton (32) and a particle electrode filler (33); the particle electrode filler (33) is placed in an insulating mesh bag and then placed in the particle electrode skeleton (32) to form the particle electrode (9); A second water inlet pipe (16) is further provided at the bottom of the electrocatalytic oxidation reaction zone, and the electrocatalytic oxidation reaction zone and the biological toxicity reduction reaction zone are connected via the second water inlet pipe (16); a water flow agitator (14) is provided in the middle of the biological toxicity reduction reaction zone, and an aeration pipe (11) connected to an external aerator (13) is provided at the bottom; and a water outlet pipe (17) for discharging treated liquid is further provided at the bottom of the biological toxicity reduction reaction zone; A water quality monitoring probe (18) and a potential sensing probe (19) are respectively provided in the electrocatalytic oxidation reaction zone and the biotoxicity reduction reaction zone; the power supply system (2) comprises a data transmission device (20), a current control device (21) and a power supply (22) connected in sequence; the data transmission device (20) receives the sewage water quality index in the electrocatalytic oxidation reaction zone monitored in real time by the water quality monitoring probe (18), and the chemical reaction potential in the biotoxicity reduction reaction zone monitored in real time by the potential sensing probe (19); the current control device (21) adjusts the current output by the power supply (22) in real time according to the sewage water quality index obtained by the data transmission device (20); The dosing system (3) includes a dosing control device (23), a drug storage tank (24), and a sprayer (26) arranged in a biotoxicity reduction reaction zone; a valve (25) is provided on a pipeline connecting the drug storage tank (24) and the sprayer (26); the dosing control device (23) adjusts the opening and closing of the valve (25) according to the chemical reaction potential obtained by the data transmission device (20); The tail gas absorption device (4) is in communication with the top of the electrochemical treatment device (1) and is used to absorb and purify the acidic and toxic tail gas generated in the electrochemical treatment device (1).

2. The electrochemical treatment device for landfill leachate with low effluent biological toxicity according to claim 1, characterized in that: The particle electrode filler (33) is a modified zeolite-activated carbon composite material with a particle size of 2 to 6 mm.

3. The electrochemical treatment device for landfill leachate with low effluent biological toxicity according to claim 1, wherein a plurality of microporous aerators (10) are evenly distributed on the aeration pipe (11).

4. According to the electrochemical treatment device for landfill leachate with low effluent biological toxicity as described in claim 1, an insulating support mesh plate (7) is horizontally fixed at the bottom of the biological toxicity reduction reaction zone, and both ends of the aeration pipe (11) are respectively fixed to the insulating support mesh plate (7) through level adjusters (12) to ensure that the aeration pipe (11) is set horizontally.

5. The electrochemical treatment device for landfill leachate with low effluent biological toxicity according to claim 1, wherein the anode plate (5) is made of titanium-plated ruthenium-iridium material; and the cathode plate (6) is made of titanium or stainless steel.

6. The electrochemical treatment device for landfill leachate with low effluent biological toxicity according to claim 5, wherein the upper parts of the anode plate (5) and the cathode plate (6) are respectively provided with a titanium-copper composite material edging for achieving uniform current distribution.

7. According to the electrochemical treatment device for landfill leachate with low effluent biological toxicity as described in claim 1, the water quality monitoring probe (18) is arranged below the liquid surface of the electrocatalytic oxidation reaction zone to measure the chemical oxygen demand, ammonia nitrogen, and total nitrogen water quality indicators in the electrocatalytic oxidation reaction zone.

8. The electrochemical treatment device for landfill leachate with low effluent biological toxicity according to claim 1, wherein the insulating support mesh plate 7 can be made of polypropylene.

9. The electrochemical treatment device for landfill leachate with low effluent biological toxicity according to claim 1, wherein the tail gas absorption device (4) comprises a ducted fan (27), an air inlet pipe (28), a circulating water tank (29), a circulating sprayer (30), and a packing tower; one end of the air inlet pipe (28) is connected to the gas collecting top of the electrochemical treatment device (1), and the other end is connected to the packing tower through a pipeline provided with the ducted fan (27); a packing tower packing (31) for absorbing tail gas is provided in the packing tower; a circulating sprayer (30) is provided at the top of the packing tower, and the circulating sprayer (30) absorbs the circulating liquid from the circulating water tank (29) and sprays it.

10. The electrochemical treatment device for landfill leachate with low effluent biological toxicity according to claim 9, wherein an insulating support mesh plate (7) is fixed in the middle of the packing tower, and the packing tower fillers (31) are respectively placed above the insulating support mesh plate (7) and at the bottom of the packing tower to form upper and lower packing layers; the packing tower fillers (31) are made of polypropylene pall rings or Raschig rings.

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