Wastewater treatment device and treatment method thereof

Abstract

The invention discloses a wastewater treatment device and a treatment method thereof, car washing wastewater is collected in a collection tank and then enters a flocculation tank to be subjected to a flocculation reaction with a flocculant, insoluble impurities in the wastewater form flocculent sludge in the process, the flocculent sludge is precipitated under the action of gravity after the wastewater enters a precipitation tank, mud and water are separated, and the wastewater is discharged from a discharge port. After the wastewater is subjected to flocculation and precipitation, most of insoluble impurities in the wastewater are removed, the residual insoluble impurities in the wastewater are filtered out through the filter assembly, and soluble organic pollutants such as oil emulsion, organic matters and detergents in the wastewater are oxidized and removed through the electrode treatment assembly, so that the wastewater reaches the standard of reuse water after being treated. The device disclosed by the invention can be used for carrying out innocent treatment on the car washing wastewater containing pollutants such as a surfactant, ammonia nitrogen, CODCr, BOD5 and total phosphorus, the turbidity of effluent treated by the device is less than or equal to 1NTU, and the cyclic utilization of water resources is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of wastewater treatment, and in particular relates to a wastewater treatment device and a treatment method thereof. Background Art

[0002] Car wash water belongs to a special industry. The high water price of special industries and the large amount of tap water used in car washes result in a large proportion of water costs in the operating expenses of car washes. Car wash wastewater mainly contains surface treatment agents, phosphorus and ammonia nitrogen substances, and contains a large number of bacteria. Car wash wastewater treatment and recycling has gradually become a hot topic in the environmental field.

[0003] The patent document with announcement number CN117566959A discloses a method for treating high-concentration ammonia nitrogen organic wastewater, comprising the following steps: pre-treating the high-concentration ammonia nitrogen organic wastewater to obtain pre-treated wastewater, wherein the pre-treatment includes filtration treatment, flocculation sedimentation treatment, pH adjustment treatment and hardness reduction treatment; electrochemically oxidizing the pre-treated wastewater with a BDD electrode as an anode to obtain primary treated wastewater and electrolytic waste gas; sending the primary treated wastewater and the electrolytic waste gas into a microbial degradation pool containing nitrifying bacteria after passing through a gas-liquid mixing device for simultaneous gas-water treatment to obtain secondary treated wastewater; sending the secondary treated wastewater into a wastewater treatment device containing autotrophic bacteria for treatment to obtain qualified wastewater. This patent is used for the treatment of high-concentration ammonia nitrogen organic wastewater. The treatment process requires the use of acidic fillers, contains certain hazardous substances, and has certain requirements for treatment conditions. The COD concentration of the wastewater treated by this method is less than 300 mg / L, ammonia nitrogen is less than 15 mg / L, and total nitrogen is less than 45 mg / L, which does not meet the vehicle washing water quality requirements in the urban miscellaneous water quality standard GB / T18920-2002. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a wastewater treatment device and a treatment method thereof.

[0005] The present invention is achieved through the following technical solutions.

[0006] A wastewater treatment device provided by the present invention comprises a wastewater collection tank, a flocculation tank, a sedimentation tank, an intermediate water tank A, an intermediate water tank B, a water storage tank and a control system, wherein the wastewater collection tank is connected to the flocculation tank through a pipeline, the flocculation tank is connected to the sedimentation tank, the sedimentation tank is connected to the intermediate water tank A, the intermediate water tank A is connected to the intermediate water tank B through a filtering component, and the intermediate water tank B is connected to the water storage tank through an electrode processing component.

[0007] Preferably, a liquid level meter A is provided on the wastewater collection tank, a water inlet pump is provided on the pipeline connecting the wastewater collection tank and the flocculation tank, a reagent box and an agitator are provided on the flocculation tank, and the reagent box is connected to the flocculation tank through a metering pump.

[0008] Preferably, a sludge interface sensor is provided on the sedimentation tank, a mud bucket is provided at the bottom of the sedimentation tank, a mud discharge pipe is provided at the lower part of the mud bucket, a mud discharge electric valve is provided at the outlet of the mud discharge pipe, and liquid level meters B are provided in the intermediate water tank A, the intermediate water tank B and the water storage tank respectively.

[0009] Preferably, the water outlet of the sedimentation tank is located at the upper part of the sedimentation tank, and a toothed weir groove is provided at the water outlet of the sedimentation tank.

[0010] Preferably, the filtering assembly includes a primary filter, a secondary filter and a tertiary filter. The liquid flowing out of the intermediate water pool A passes through the filter inlet pump, the primary filter, the secondary filter and the tertiary filter in sequence and then enters the intermediate water pool B. The primary filter and the secondary filter are connected to the wastewater collection pool through pipes.

[0011] Preferably, the primary filter and the secondary filter are filtered by quartz sand, and the filter particle size of the tertiary filter is 1-2 μm.

[0012] Preferably, the electrode treatment component includes an oxidation water inlet pump and an electrode module. The liquid flowing out of the intermediate water tank B passes through the oxidation water inlet pump and the electrode module in sequence and then enters the water storage tank. A water replenishment electric valve is provided on the water storage tank.

[0013] Preferably, the electrode module comprises a shell and electrode strips, and the electrode strips extend into the shell to form a baffled flow channel.

[0014] Preferably, the electrode strips are silicon-based boron-doped diamond thin film electrodes.

[0015] A treatment method for a wastewater treatment device comprises the following steps:

[0016] S1: The wastewater treatment device is automatically controlled by the control system;

[0017] S2: When the liquid level of the intermediate water tank A has not reached the high level and the liquid level of the wastewater collection tank is higher than the low level, the control system controls the water inlet pump to pump wastewater from the wastewater collection tank into the flocculation tank, and at the same time controls the metering pump to pump flocculation reagent from the reagent box into the flocculation tank, controls the agitator to start stirring, and the wastewater enters the sedimentation tank after flocculation reaction;

[0018] S3: After the wastewater undergoing flocculation reaction enters the sedimentation tank for separation, the water enters the intermediate water tank A through the toothed weir groove;

[0019] S4: When the sludge height in the sedimentation tank reaches the preset value, the control system controls the sludge discharge electric valve to open and discharge the floccules at the bottom of the sedimentation tank. When the sludge height drops to the preset value, the sludge discharge electric valve is controlled to close;

[0020] S5: When the liquid level of the intermediate water tank B has not reached the high level and the liquid level of the intermediate water tank A is higher than the low level, the control system controls the filter water inlet pump to start, pumping the water in the intermediate water tank A into the filter assembly, and the water out of the filter assembly enters the intermediate water tank B;

[0021] S6: When the liquid level in the water storage tank has not reached the high level and the liquid level in the intermediate water tank B is higher than the low level, the control system controls the oxidation water inlet pump to start, pumping the water in the intermediate water tank B into the electrode module, and at the same time energizes the electrode module to operate, and the water processed by the electrode module enters the water storage tank;

[0022] S7: When the liquid level in the water tank is lower than the water replenishment level, the control system controls the water replenishment electric valve to open and replenish water into the water tank. When the liquid level in the water tank is higher than the water replenishment level, the control system controls the water replenishment electric valve to close and stop replenishing water.

[0023] The beneficial effects of the present invention are:

[0024] (1) The device of the present invention can be used to treat surfactant (LAS), ammonia nitrogen, COD Cr The car washing wastewater is harmlessly treated to remove pollutants such as BOD5 and total phosphorus. The treated water quality meets the vehicle washing water quality requirements in the urban miscellaneous water quality standard for urban sewage recycling (GB / T18920-2002), realizing the recycling of water resources.

[0025] (2) The setting of the filtering component, the turbidity of the effluent after treatment by this device is ≤1NTU, which is far lower than the requirement of ≤5NTU for vehicle washing water quality in the "Urban Wastewater Recycling Urban Miscellaneous Water Quality Standard" (GB / T 18920-2002), and the treatment effect is good.

[0026] (3) This device can solve the problems of odor, virus breeding, algae breeding, etc. of car wash wastewater reuse, meet the sanitary and safety requirements of water quality for human contact, and can also collect and deeply treat car wash wastewater for recycling, reduce environmental pollution, reduce the amount of tap water used in car washes, and save water resources.

[0027] (4) The electrode strips of the refractory BDD electrode module increase the contact area between the solution to be treated and the electrode plate, effectively promoting the electrochemical reaction to achieve high-efficiency degradation.

[0028] (5) Based on electrochemical oxidation, strong oxidizing hydroxyl radicals (OH·), active oxygen free radicals (O2·), ozone (O3), hydrogen peroxide (H2O2), etc. are generated on the surface of the anode electrode strip of the BDD electrode module to disinfect the water body, thereby achieving the effect of water disinfection and sterilization.

[0029] (6) Through the setting of the PLC automatic control system, feedback signals from the ultrasonic level meter, the fully automatic medium filter, the mud discharge electric valve, the pressure level meter, etc. are received, so that the device can operate fully automatically without manual operation and control. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the present invention;

[0031] Figure 2 It is a schematic diagram of the structure of the present invention;

[0032] Figure 3 is a schematic diagram of the present invention;

[0033] Figure 4 It is a schematic diagram of the structure of the sedimentation tank of the present invention;

[0034] Figure 5 is a top view of a sedimentation tank of the present invention;

[0035] Figure 6 It is a structural schematic diagram of the electrode module of the present invention;

[0036] In the figure: 1-wastewater collection tank, 2-flocculation tank, 21-medicine box, 22-agitator, 23-metering pump, 3-sedimentation tank, 31-sludge interface sensor, 32-mud bucket, 33-sludge discharge pipe, 34-sludge discharge electric valve, 35-toothed weir, 4-intermediate water tank A, 5-intermediate water tank B, 6-water storage tank, 61-water replenishment electric valve, 7-primary filter, 71-filter inlet pump, 8-secondary filter, 9-tertiary filter, 10-oxidation inlet pump, 11-liquid level meter A, 12-inlet pump, 13-liquid level meter B, 14-electrode module, 141-housing, 142-electrode strips, 101-control system. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is further described below, but the scope of protection claimed is not limited to the description.

[0038] Example:

[0039] like Figure 1 As shown, a wastewater treatment device includes a wastewater collection tank 1, a flocculation tank 2, a sedimentation tank 3, an intermediate water tank A4, an intermediate water tank B5, a water storage tank 6 and a control system 101. The wastewater collection tank 1 is connected to the flocculation tank 2 through a pipeline, the flocculation tank 2 is connected to the sedimentation tank 3, the sedimentation tank 3 is connected to the intermediate water tank A4, the intermediate water tank A4 is connected to the intermediate water tank B5 through a filtering component, and the intermediate water tank B5 is connected to the water storage tank 6 through an electrode treatment component.

[0040] A liquid level meter A11 is arranged on the wastewater collection tank 1 , a water inlet pump 12 is arranged on the pipeline connecting the wastewater collection tank 1 and the flocculation tank 2 , a reagent box 21 and an agitator 22 are arranged on the flocculation tank 2 , and the reagent box 21 is connected to the flocculation tank 2 via a metering pump 23 .

[0041] A sludge interface sensor 31 is provided on the sedimentation tank 3, a mud bucket 32 ​​is provided at the bottom of the sedimentation tank 3, a mud discharge pipe 33 is provided at the lower part of the mud bucket 32, a mud discharge electric valve 34 is provided at the outlet of the mud discharge pipe 33, and liquid level meters B13 are respectively provided in the intermediate water tank A4, the intermediate water tank B5 and the water storage tank 6.

[0042] The water outlet of the sedimentation tank 3 is located at the upper part of the sedimentation tank 3 , and a toothed weir groove 35 is arranged at the water outlet of the sedimentation tank 3 .

[0043] The filtering assembly includes a primary filter 7, a secondary filter 8 and a tertiary filter 9. The liquid flowing out of the intermediate water tank A4 passes through the filter inlet pump 71, the primary filter 7, the secondary filter 8 and the tertiary filter 9 in sequence and then enters the intermediate water tank B5. The primary filter 7 and the secondary filter 8 are connected to the wastewater collection tank 1 through a pipeline.

[0044] The primary filter 7 and the secondary filter 8 are filtered by quartz sand, and the filter particle size of the tertiary filter 9 is 1-2 μm.

[0045] The electrode treatment assembly includes an oxidation water inlet pump 10 and a BDD electrode module 14 . The liquid flowing out of the intermediate water tank B5 passes through the oxidation water inlet pump 10 and the BDD electrode module 14 in sequence and then enters the water storage tank 6 . A water replenishment electric valve 61 is provided on the water storage tank 6 .

[0046] The BDD electrode module 14 includes a shell 141 and electrode strips 142 . The electrode strips 142 extend into the shell 141 to form a baffled flow channel.

[0047] The electrode strips 142 are silicon-based boron-doped diamond thin film electrodes.

[0048] A treatment method for a wastewater treatment device comprises the following steps:

[0049] S1: The wastewater treatment device is automatically controlled by the control system 101. The liquid level gauge A11 and the liquid level gauge B13 transmit the liquid level signals of the wastewater collection tank 1, the intermediate water tank A, the intermediate water tank B5 and the water storage tank 6 to the control system 101. The ultrasonic sludge interface sensor 31 transmits the sludge height signal in the sedimentation tank 3 to the control system 101.

[0050] S2: When the liquid level of the intermediate water tank A4 has not reached the high level and the liquid level of the wastewater collection tank 1 is higher than the low level, the control system 101 controls the water inlet pump 12 to pump wastewater from the wastewater collection tank 1 into the flocculation tank 2, and controls the metering pump 23 to pump flocculation reagent from the reagent box 21 into the flocculation tank 2, and controls the agitator 22 to start stirring. The wastewater and the flocculation reagent undergo flocculation reaction in the flocculation tank 2 through stirring to produce flocculent particles, and then enter the sedimentation tank 3;

[0051] S3: After the wastewater undergoing flocculation reaction enters the sedimentation tank 3, the flocculent particles settle to the bottom of the sedimentation tank 3 under the action of gravity, and the separated water enters the intermediate water tank A4 through the toothed weir groove 35.

[0052] S4: After the sludge height in the sedimentation tank 3 reaches a preset value, the control system 101 controls the sludge discharge electric valve 34 to open, and discharges the floccules at the bottom of the sedimentation tank 3. After the sludge height drops to a preset value, the sludge discharge electric valve 34 is controlled to close;

[0053] S5: When the liquid level of the intermediate water tank B5 is not at the high level and the liquid level of the intermediate water tank A4 is higher than the low level, the control system 101 controls the filter inlet pump 71 to start, and pumps the water in the intermediate water tank A4 into the filter assembly of the first-stage filter 7, the second-stage filter 8, and the third-stage filter 9 connected in series, and the residual suspended matter in the water is filtered out by the filter assembly, and the water out of the filter assembly enters the intermediate water tank B5;

[0054] S6: When the liquid level of the water storage tank 6 has not reached the high level and the liquid level of the intermediate water tank B5 is higher than the low level, the control system 101 controls the oxidation water inlet pump 10 to start, pumping the water in the intermediate water tank B5 into the BDD electrode module 14, and at the same time energizing the BDD electrode module 14. When energized, the BDD electrode module 14 can decompose the soluble organic pollutants in the treated water, and the effluent meets the standards and enters the water storage tank 6;

[0055] S7: When the liquid level of the water tank 6 is lower than the water replenishment level, the control system 101 controls the water replenishment electric valve 61 to open and replenish water into the water tank 6. When the liquid level of the water tank 6 is higher than the water replenishment level, the control system 101 controls the water replenishment electric valve 61 to close and stop replenishing water.

[0056] Wastewater collection pool 1: It is used to collect wastewater generated during the car washing process and is an underground box structure.

[0057] Liquid level meter A11: It is an ultrasonic liquid level meter installed on the wastewater collection tank 1 and is used to measure the water level in the wastewater collection tank 1.

[0058] The flocculation tank 2 is used for flocculation reaction, the sedimentation tank 3 is used for floc sedimentation and separation, the intermediate water tank A4 and the intermediate water tank B5 are used to store water in the treatment process, and the water storage tank 6 is used to store treated water.

[0059] Inlet pump 12: used to pump car wash wastewater from the wastewater collection tank 1 into the flocculation tank 2.

[0060] Agent box 21: for storing liquid flocculation agent, usually polyaluminium chloride (PAC) liquid agent.

[0061] Metering pump 23: used to pump the liquid flocculation agent in the agent box 21 into the flocculation tank 2.

[0062] Agitator 22: The upper part is a reduction motor, and the lower part is a stirring blade. The reduction motor is connected to the flocculation tank 2 through a support frame, and the output shaft of the reduction motor is connected to the stirring blade. It is used to stir and mix the car wash wastewater and the flocculation agent, so that the car wash wastewater and the flocculation agent react to produce a flocculation reaction, so that the suspended matter in the car wash wastewater flocculates into flocs, and at the same time, chemical phosphorus removal is carried out through PAC, and the total phosphorus in the car wash wastewater is synergistically treated to achieve the purpose of removing the total phosphorus in the car wash wastewater.

[0063] Mud hopper 32 : located at the bottom of the sedimentation tank 3 , in an inverted cone shape, used to concentrate the flocculent sludge precipitated in the sedimentation tank 3 in the middle of the mud hopper 32 and discharge it to the mud discharge pipe 33 .

[0064] The mud discharge pipe 33 is a pipe located at the lower part of the mud bucket 32 ​​and is used to discharge the flocculent mud in the mud bucket 32 ​​.

[0065] The sludge discharge electric valve 34 is installed on the outer part of the sludge discharge pipe 33 after it passes through the sedimentation tank 3, and is used to control the discharge of flocculent sludge.

[0066] The sludge interface sensor 31 is an ultrasonic sludge interface sensor, which is located at the upper part of the sedimentation tank 3 and uses ultrasonic waves to detect the mud-water interface height of the flocculent sludge in the sedimentation tank 3, that is, to detect the sludge height.

[0067] Toothed weir groove 35: The toothed weir groove 35 is horizontal at the outlet of the sedimentation tank 3. Both ends of the toothed weir groove 35 are connected to the sedimentation tank 3 and water cannot enter. The side of the toothed weir groove 35 opposite to the outlet of the sedimentation tank 3 is serrated. Water enters the toothed weir groove 35 from this surface and then flows out from the outlet of the sedimentation tank 3. This arrangement enables the outlet water flow of the sedimentation tank 3 to flow in an orderly manner, avoiding confusion and lamination of the water flow, thereby making the water flow evenly distributed and ensuring the mud-water separation effect of the sedimentation tank 3.

[0068] Filter water inlet pump 71: draws water from the intermediate water tank 1 and pumps it into the primary filter 7.

[0069] The primary filter 7 and the secondary filter 8 are quartz sand filters, which can be fully automatically operated, filter the water from the intermediate water tank 1, and further filter the suspended matter in the water. They operate according to the set time. When the backwash time is reached, they start to automatically backwash, wash out the suspended matter trapped in the quartz sand, and automatically enter the operating state after the backwash is completed. The two quartz sand filters have a backwash interlock, and only one quartz sand filter will backwash at the same time to prevent the two filters from backwashing at the same time and causing invalid backwashing. The backwash sewage can enter the wastewater collection tank 1 through the pipeline. The quartz sand particle size in the primary filter 7 is 4-8mm, and the quartz sand particle size in the secondary filter 8 is 1-2mm.

[0070] The third-stage filter has a filter particle size of 1 to 2 μm and is used to filter out suspended matter in the water. The effluent enters the intermediate water pool 2.

[0071] Oxidation water inlet pump 10: pumps water from the intermediate water pool 2 and pumps it into the baffled silicon-based boron-doped diamond film BDD electrode module 14.

[0072] BDD electrode module 14: It is a baffled silicon-based boron-doped diamond film electrode module. The structure of the electrolysis module is baffled, which increases the contact time between water and the anode of the electrode strip 142. The electrochemical oxidation principle is used to deeply treat the car wash wastewater. The electrochemical oxidation technology using silicon-based boron-doped diamond material as the anode degrades organic matter in ways including direct oxidation and indirect oxidation. Both ends of the shell 141 are conical, and the side where the conical part is connected to the middle of the shell is the large end. The electrode strip 142 includes an anode and a cathode, such as Figure 6 As shown, the one extending into the shell 141 from the left side is the anode, and the one extending into the shell 141 from the right side is the cathode.

[0073] Direct oxidation is to achieve the oxidation and removal of organic matter (oil emulsion, organic matter and detergents) and ammonia nitrogen by adsorbing organic pollutants on the surface of the anode electrode strip 142 in the form of electron transfer; organic matter can be directly converted into CO2 and H2O, and ammonia nitrogen is oxidized into nitrogen gas.

[0074] Indirect oxidation is to produce strong oxidizing hydroxyl radicals (OH·), active oxygen free radicals (O2·), ozone (O3), hydrogen peroxide (H2O2), etc. on the surface of the BDD anode electrode strip 142 under the action of direct current, oxidizing and decomposing organic pollutants into harmless carbon dioxide (CO2) and water molecules (H2O), and oxidizing ammonia nitrogen into nitrogen. In addition, the strong oxidizing hydroxyl radicals (OH·), active oxygen free radicals (O2·), ozone (O3), hydrogen peroxide (H2O2), etc. produced on the surface of the BDD anode electrode strip 142 directly react with bacteria and viruses, destroying organelles and DNA and RNA, disrupting bacterial metabolism, and causing bacterial death, thereby achieving the purpose of water disinfection and sterilization.

[0075] Liquid level gauge B13: It is a pressure type liquid level gauge, which is installed at the lower pipe openings of the intermediate water tank A4, the intermediate water tank B5 and the water storage tank 6 respectively. It uses the pressure principle to detect the water level in each tank and transmits the water level signal to the automatic control system.

[0076] The water replenishment electric valve 61 controls the tap water to enter the water tank 6, and replenishes water into the water tank 6 when the water level of the water tank 6 is lower than the preset value to prevent the rear-end water-using equipment from lacking water.

[0077] Control system 101: The core is a programmable logic controller (PLC). The signals of the above-mentioned level meter A11, water inlet pump 12, metering pump 23, agitator 22, sludge discharge electric valve 34, sludge interface sensor 31, filter water inlet pump 71, oxidation water inlet pump 10, BDD electrode module 14, level meter B13 and water replenishment electric valve 61 are all connected to the control system 101, and the control system 101 is fully automatically controlled and operated. The circuit structure is a relatively mature existing technology and will not be repeated in this application.

[0078] The daily car wash wastewater was tested before and after being treated with this device. The results are shown in the following table. The implementation standard of the standard limit is the "Urban Wastewater Recycling Urban Miscellaneous Water Quality Standard" (GB / T 18920-2002) Urban Miscellaneous Water Quality Standard.

[0079]

[0080] It can be seen from the above table that after being treated by the device of the present application, the values ​​of ammonia nitrogen, total phosphorus, suspended solids and anionic surfactants are greatly reduced, and at the same time, it has a killing effect on Escherichia coli, which meets the water quality standards.

Claims

1. A wastewater treatment device, characterized in that: The invention comprises a wastewater collection tank (1), a flocculation tank (2), a sedimentation tank (3), an intermediate water tank A (4), an intermediate water tank B (5), a water storage tank (6) and a control system (101), wherein the wastewater collection tank (1) is connected to the flocculation tank (2) through a pipeline, the flocculation tank (2) is connected to the sedimentation tank (3), the sedimentation tank (3) is connected to the intermediate water tank A (4), the intermediate water tank A (4) is connected to the intermediate water tank B (5) through a filtering component, and the intermediate water tank B (5) is connected to the water storage tank (6) through an electrode processing component.

2. A wastewater treatment device according to claim 1, characterized in that: A liquid level meter A (11) is provided on the wastewater collection tank (1), a water inlet pump (12) is provided on the pipeline connecting the wastewater collection tank (1) and the flocculation tank (2), a reagent box (21) and an agitator (22) are provided on the flocculation tank (2), and the reagent box (21) is connected to the flocculation tank (2) via a metering pump (23).

3. A wastewater treatment device according to claim 1, characterized in that: A sludge interface sensor (31) is arranged on the sedimentation tank (3), a sludge bucket (32) is arranged at the bottom of the sedimentation tank (3), a sludge discharge pipe (33) is arranged at the lower part of the sludge bucket (32), a sludge discharge electric valve (34) is arranged at the outlet of the sludge discharge pipe (33), and liquid level meters B (13) are arranged in the intermediate water tank A (4), the intermediate water tank B (5) and the water storage tank (6), respectively.

4. A wastewater treatment device as claimed in claim 3, characterized in that: The water outlet of the sedimentation tank (3) is located at the upper part of the sedimentation tank (3), and a toothed weir groove (35) is arranged at the water outlet of the sedimentation tank (3).

5. A wastewater treatment device according to claim 1, characterized in that: The filter assembly comprises a primary filter (7), a secondary filter (8) and a tertiary filter (9); the liquid flowing out of the intermediate water pool A (4) passes through a filter water inlet pump (71), the primary filter (7), the secondary filter (8) and the tertiary filter (9) in sequence and then enters the intermediate water pool B (5); the primary filter (7) and the secondary filter (8) are connected to the wastewater collection pool (1) through a pipeline.

6. A wastewater treatment device as claimed in claim 5, characterized in that: The primary filter (7) and the secondary filter (8) are filtered by quartz sand, and the filter particle size of the tertiary filter (9) is 1 to 2 μm.

7. A wastewater treatment device according to claim 1, characterized in that: The electrode treatment assembly comprises an oxidation water inlet pump (10) and an electrode module (14); the liquid flowing out of the intermediate water tank B (5) passes through the oxidation water inlet pump (10) and the electrode module (14) in sequence and then enters the water storage tank (6); and a water replenishment electric valve (61) is provided on the water storage tank (6).

8. A wastewater treatment device according to claim 7, characterized in that: The electrode module (14) comprises a shell (141) and electrode strips (142), wherein the electrode strips (142) extend into the shell (141) to form a baffled flow channel.

9. A wastewater treatment device as claimed in claim 8, characterized in that: The electrode strip (142) is a silicon-based boron-doped diamond film electrode.

10. A method for treating wastewater according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1: The wastewater treatment device is automatically controlled by a control system (101); S2: When the liquid level of the intermediate water tank A (4) has not reached the high level and the liquid level of the wastewater collection tank (1) is higher than the low level, the control system (101) controls the water inlet pump (12) to pump wastewater from the wastewater collection tank (1) into the flocculation tank (2), and at the same time controls the metering pump (23) to pump flocculation reagent from the reagent box (21) into the flocculation tank (2), controls the stirrer (22) to start stirring, and the wastewater enters the sedimentation tank (3) after flocculation reaction occurs; S3: The wastewater that has undergone flocculation reaction enters the sedimentation tank (3) and after separation, the water enters the intermediate water tank A (4) through the toothed weir groove (35); S4: After the sludge height in the sedimentation tank (3) reaches a preset value, the control system (101) controls the sludge discharge electric valve (34) to open, and discharges the floccules at the bottom of the sedimentation tank (3). After the sludge height drops to a preset value, the sludge discharge electric valve (34) is controlled to close; S5: When the liquid level of the intermediate water tank B (5) has not reached the high level and the liquid level of the intermediate water tank A (4) is higher than the low level, the control system (101) controls the filter water inlet pump (71) to start, pumping the water in the intermediate water tank A (4) into the filter assembly, and the water out of the filter assembly enters the intermediate water tank B (5); S6: When the liquid level of the water storage tank (6) has not reached the high level and the liquid level of the intermediate water tank B (5) is higher than the low level, the control system (101) controls the oxidation water inlet pump (10) to start, pumping the water in the intermediate water tank B (5) into the electrode module (14), and at the same time, the electrode module (14) is powered on, and the water treated by the electrode module (14) enters the water storage tank (6); S7: When the liquid level in the water storage tank (6) is lower than the water replenishment level, the control system (101) controls the water replenishment electric valve (61) to open and replenish water into the water storage tank (6); when the liquid level in the water storage tank (6) is higher than the water replenishment level, the control system (101) controls the water replenishment electric valve (61) to close and stop replenishing water.

Images