High organic waste water treatment system

Abstract

This invention relates to an organic wastewater treatment system, belonging to the field of wastewater treatment technology. The organic wastewater treatment system of this invention includes a multi-stage treatment device, comprising a primary electrocatalytic oxidation treatment device and a secondary electrocatalytic oxidation treatment device. Wastewater treated by the primary electrocatalytic oxidation treatment device enters the secondary electrocatalytic oxidation treatment device for COD removal. The primary electrocatalytic oxidation treatment device includes a housing, a catalytic oxidation reaction zone and an electrocatalytic oxidation zone disposed within the housing. The catalytic oxidation reaction zone is located at the top layer of the housing and contains packing material. The electrocatalytic oxidation zone is located below the catalytic oxidation reaction zone and contains n sets of parallel-connected electrode plates. Each set of electrode plates includes a first anode plate and a first cathode plate spaced apart, with packing material disposed between each first anode plate and first cathode plate.

Description

[0001] This application is a divisional application of the application filed on July 29, 2025, with application number CN202511049687.2 and titled "High Organic Wastewater Treatment System for Medical Institutions". Technical Field

[0002] This invention relates to the field of wastewater treatment technology, and in particular to a wastewater treatment system with high organic matter content. Background Technology

[0003] Medical wastewater is often rich in various pathogens, bacteria, heavy metals, disinfectants, organic solvents, and even radioactive substances. Therefore, it must undergo strict treatment before discharge. Improper treatment can cause significant environmental pollution, spread viruses, lead to heavy metal poisoning, and cause radiation damage, seriously threatening public health. Current methods for treating medical wastewater include combinations of biological contact methods with traditional disinfection methods, and membrane bioreactors with traditional disinfection methods. However, these methods suffer from low treatment efficiency, difficulty in removing radioactive materials from the wastewater, and a lack of separate treatment and recovery of the waste gases generated during treatment. Summary of the Invention

[0004] This invention provides a wastewater treatment system with high organic matter content to solve at least one of the above-mentioned technical problems.

[0005] This invention provides a high-organic-content wastewater treatment system, including a multi-stage treatment device, which includes an electrocatalytic oxidation primary treatment device and an electrocatalytic oxidation secondary treatment device. Wastewater treated by the electrocatalytic oxidation primary treatment device enters the electrocatalytic oxidation secondary treatment device for COD removal. The electrocatalytic oxidation primary treatment device includes a housing, a catalytic oxidation reaction zone and an electrocatalytic oxidation zone disposed within the housing. The catalytic oxidation reaction zone is located at the top layer of the housing and is filled with packing material. The electrocatalytic oxidation zone is located below the catalytic oxidation reaction zone and is provided with n sets of parallel electrode plates. Each set of electrode plates includes a first anode plate and a first cathode plate disposed at intervals, and packing material is disposed between each first anode plate and the first cathode plate.

[0006] In one embodiment, the surface of the first anode plate is coated with a noble metal coating, and the first cathode plate is a nickel plate.

[0007] In one embodiment, the distance between the first anode plate and the first cathode plate is 20mm-60mm, and the current density of the electrocatalytic oxidation primary treatment device is 30A / m. 2 -80A / m 2 .

[0008] In one embodiment, the packing material is a loose, porous granular structure carrying a catalyst, wherein the catalyst is manganese dioxide, iron, copper, or a noble metal.

[0009] In one embodiment, the electrocatalytic oxidation zone is configured with at least two layers, and a turbulent water distributor is provided above each layer of the electrocatalytic oxidation zone. The distributor extends along the length of the tank and covers the entire length of the tank, and is used to uniformly distribute water to each layer of the electrocatalytic oxidation zone.

[0010] In one embodiment, a membrane enrichment and separation system is further included, the membrane enrichment and separation system comprising: The first intermediate water tank is connected to the output pipe of the tank body to receive water that has been treated by the electrocatalytic oxidation primary treatment device. A microfiltration device, which is connected to the first intermediate water tank; An organic membrane module, which is connected to the microfiltration device; The organic membrane module has one output port connected to a second intermediate water tank, which is connected to the electrocatalytic oxidation secondary treatment device; the organic membrane module has a second output port connected to an input port; and the organic membrane module has a third output port connected to a return pipe, which is connected to a wastewater inlet at the bottom of the container.

[0011] In one embodiment, the electrocatalytic oxidation secondary treatment device includes a second cation chamber and a second anion chamber, wherein the second cation chamber is defined by an anode catalyst separator and a cation membrane, and the second anion chamber is defined by the cation membrane and a cathode catalyst separator; Water from the second intermediate water tank enters the anode catalyst partition and undergoes an oxidation reaction in the second anode chamber. Wastewater flows through the second anode chamber and then into the second anion chamber.

[0012] In one embodiment, the outlet of the anode catalyst separator and the inlet of the cathode catalyst separator are fluidly connected by a connecting pipe, and the wastewater flows through the second anode chamber and can then enter the second cathode chamber through the connecting pipe to carry out the reaction.

[0013] In one embodiment, the anode catalyst separator and / or the cathode catalyst separator are filled with catalyst packing material, the catalyst packing material comprising a support and a catalyst, wherein the support is spherical alumina and the catalyst is manganese dioxide, iron or copper.

[0014] In one embodiment, the electrocatalytic oxidation secondary treatment device further includes a second anode plate located on the side of the anode catalyst separator away from the cation membrane and a second cathode plate located on the side of the cathode catalyst separator away from the cation membrane. The second anode plate and the second cathode plate are made of the same material, both of which are made of titanium plates coated with precious metals.

[0015] Compared with the prior art, the advantages of the present invention are that the electrocatalytic oxidation primary treatment device and the electrocatalytic oxidation secondary treatment device can generate hydroxyl groups, which can be used to sterilize and disinfect medical wastewater by utilizing their strong oxidizing properties. Furthermore, the multi-stage catalytic oxidation effect of the electrocatalytic oxidation primary treatment device and the electrocatalytic oxidation secondary treatment device can accelerate the attenuation of radioactive substances in medical wastewater, thereby reducing the impact of radioactive substances. In addition, the waste gas generated in the electrocatalytic oxidation primary treatment device is treated and discharged in compliance with standards through the waste gas emission and treatment system, so that the entire treatment process of the medical institution's high organic wastewater treatment system generates no hazardous waste or medical waste, which has environmentally friendly characteristics. Attached Figure Description

[0016] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0017] Figure 1 This is a schematic diagram of the structure of a medical institution high-organic-content wastewater treatment system in an embodiment of the present invention; Figure 2 yes Figure 1 Schematic diagram of the second gas pipeline in the middle; Figure 3 yes Figure 1 Schematic diagram of the intermediate water treatment unit; Figure 4 yes Figure 1 Schematic diagram of the structure of the electro-catalytic oxidation secondary treatment unit; Figure 5 yes Figure 1 A magnified structural schematic diagram of the electrocatalytic oxidation secondary treatment unit; Figure 6 yes Figure 5 Front view of the Zhongyang extreme plate; Figure 7 yes Figure 5 Front view of the intermediate cathode extreme plate; Figure 8 yes Figure 5 Front view of the separator of the middle anode catalyst; Figure 9 yes Figure 5 Side view of the separator of the central anode catalyst; Figure 10 yes Figure 5Front view of the middle cathode catalyst separator; Figure 11 yes Figure 5 Side view of the middle cathode catalyst separator; Figure 12 yes Figure 1 A magnified structural schematic diagram of the electrocatalytic oxidation region shown.

[0018] Figure label: 400. Electrocatalytic oxidation primary treatment unit; 401. Wastewater tank; 402. First wastewater pump; 403. Wastewater regulating valve; 404. Second intermediate water tank; 480. Packing material; 460. Housing; 461. Wastewater inlet; 462. Catalytic oxidation reaction zone; 463. Electrocatalytic oxidation zone; 464. Water distributor; 465. Output pipe; 410. Turbulent flow redistributor; 420. Membrane enrichment and separation system; 430. Magnetic level gauge; 414. Explosion-proof junction box; 421. Intermediate water tank; 422. Booster pump; 423. Microfiltration device; 424. High-pressure pump; 425. Organic membrane module; 426. Circulating booster pump; 428. Output regulating valve; 440. First gas pipeline; 441. Gas distributor; 442. Nitrogen pressure reducing valve; 443. Nitrogen regulating valve; 450. Second gas pipeline; 453. Exhaust fan; 454. Oxidant liquid spray tower; 455. Oxidant circulation pump; 466. Gas distribution pipe; 4541. Tower body; 4542. Circulation tank; 4543. Spray pipe; 4544. Catalyst packing; 4545. Alkali circulation pump; 200. Water production unit; 300. Electrocatalytic oxidation secondary treatment unit; 500. Power supply unit; 101. Second wastewater pump; 311. First anode plate; 312. First cathode plate; 600. Electrocatalytic oxidation secondary treatment unit; 601. Anode end plate; 602. Gasket; 603. Second anode plate; 604. Separator; 605. Anode catalyst separator; 606. Protective mesh; 607. Cation membrane; 608. Cathode catalyst separator; 609. Second cathode plate; 610. Cathode end plate; 611. Connecting pipeline; 612. Catalyst packing; 6031, Anode plate terminal; 6091, Cathode plate terminal; 6051, Anode catalyst chamber; 6052, Anode catalyst flow channel; 6053, Main flow channel of anode catalyst; 6054, Branch flow channel of anode catalyst; 6081, cathode catalyst chamber; 6082, cathode catalyst flow channel; 6083, cathode catalyst main flow channel; 6084, cathode catalyst branch flow channel. Detailed Implementation

[0019] The invention will now be further described with reference to the accompanying drawings.

[0020] like Figure 1 As shown, the present invention provides a treatment system for high organic wastewater in medical institutions, wherein the high organic wastewater in medical institutions includes wastewater from medical research and development institutions, which involves various bacteria, viruses and microorganisms.

[0021] The medical institution high-organic-content wastewater treatment system of the present invention includes an electrocatalytic oxidation primary treatment device 400, a membrane enrichment and separation system 420, a nitrogen purging system, a waste gas emission and treatment system, and an electrocatalytic oxidation secondary treatment device 600. Through multi-stage treatment, such as the primary treatment by the electrocatalytic oxidation primary treatment device 400 and the secondary treatment by the electrocatalytic oxidation secondary treatment device 600, the medical institution high-organic-content wastewater treatment system of the present invention can perform multi-stage treatment of wastewater, thereby enabling multi-stage treatment of wastewater containing viruses and ensuring that the viruses and bacteria therein can be completely eliminated. Therefore, it is understood that the medical institution high-organic-content wastewater treatment system of the present invention may also include more stages of treatment devices, such as tertiary treatment devices, quaternary treatment devices, etc.

[0022] The electrocatalytic oxidation primary treatment device 400 includes a housing 460, a catalytic oxidation reaction zone 462 and an electrocatalytic oxidation zone 463 disposed in the housing 460.

[0023] like Figure 1 As shown, the catalytic oxidation reaction zone 462 is located at the top of the box 460, and is equipped with packing 480. The packing 480 is a loose porous granular structure (e.g., alumina balls) that carries a catalyst. The catalyst is manganese dioxide, iron, copper or a precious metal.

[0024] The electrocatalytic oxidation zone 463 is located below the catalytic oxidation reaction zone 462. It can be configured as two or more layers. Each layer of the electrocatalytic oxidation zone 463 is equipped with a turbulent water distributor 410, which extends along the length of the tank 460 and covers the entire length of the tank 460, and is used to evenly distribute water to each layer of the electrocatalytic oxidation zone 463.

[0025] like Figure 12As shown, multiple sets of electrode plates can be arranged in parallel in the electrocatalytic oxidation zone 463. The electrode plates include a first anode plate 311 and a first cathode plate 312. The multiple first anode plates 311 and multiple first cathode plates 312 are arranged alternately, for example, in the following order: first first anode plate 311, first first cathode plate 312, second first anode plate 311, second first cathode plate 312, third first anode plate 311, third first cathode plate 312… ... nth first cathode plate 312, nth first anode plate 311. Here, n is the number of electrode plate sets, which is a positive integer.

[0026] A filler 480 is provided between the first anode plate 311 and the first cathode plate 312.

[0027] The surface of the first anode plate 311 is coated with a precious metal coating such as ruthenium and iridium. The first cathode plate 312 is a nickel plate. The distance between the first anode plate 311 and the first cathode plate 312 can be 20mm-60mm. This is because if the distance between the first anode plate 311 and the first cathode plate 312 is too large, the required voltage and power will be higher; conversely, if the distance between the first anode plate 311 and the first cathode plate 312 is too small, the proportion of filler 480 between them will be reduced. Therefore, the distance is set at 20mm-60mm, preferably 20mm-40mm; the current density of the electrocatalytic oxidation primary treatment device is controlled at 30A / m. 2 -80A / m 2 Preferably 30 A / m 2 -60A / m 2 .

[0028] The packing material 480 is a loose, porous granular structure (e.g., alumina spheres) supporting a catalyst, which is manganese dioxide, iron, copper, or a precious metal.

[0029] like Figure 1 As shown, the bottom of the housing 460 is provided with a wastewater inlet 461, which is connected to the wastewater tank 401 and also to the organic membrane module 425 described below.

[0030] An explosion-proof junction box 414 is installed on the enclosure 460, which is connected to the power unit 500 to provide explosion protection and improve safety during use. The power unit 500 is a DC power supply.

[0031] Wastewater in wastewater tank 401 is fed into wastewater inlet 461 via wastewater pipe. The first wastewater pump 402 on the wastewater pipe can pump the wastewater, and the wastewater regulating valve 403 on the wastewater pipe can control the flow rate and velocity of the wastewater.

[0032] Wastewater entering from the bottom of the tank 460 flows sequentially from bottom to top into each electrocatalytic oxidation zone 463 and catalytic oxidation reaction zone 462 via a water distributor 464. After the first anode plate 311 and the first cathode plate 312 of each electrocatalytic oxidation zone 463 are connected to the power unit 500, a large number of hydroxyl groups are generated in the electrocatalytic oxidation zone 463. Various viruses in the wastewater are oxidized and killed by the hydroxyl groups. Under the action of the packing material 480 in each electrocatalytic oxidation zone 463, the wastewater undergoes a catalytic oxidation reaction at the interface of the first anode plate 311. The generated hydroxyl groups work synergistically with the catalyst in the packing material 480 in each electrocatalytic oxidation zone 463 and catalytic oxidation reaction zone 462 to continuously oxidize and decompose organic matter. Finally, the organic matter is oxidized and decomposed into carbon dioxide and water by the hydroxyl groups; ammonia nitrogen releases nitrogen gas, and COD is oxidized and degraded into carbon dioxide and water.

[0033] like Figure 1 As shown, an output pipe 465 is provided on the top of the housing 460, which is connected to the membrane enrichment and separation system 420. Water generated in the catalytic oxidation reaction zone 462 is input into the membrane enrichment and separation system 420 through the output pipe 465.

[0034] Furthermore, since the wastewater has poor conductivity, 10,000 ppm of sodium sulfate can be added to the wastewater to improve its conductivity.

[0035] like Figure 1 and Figure 2 As shown, a first gas pipeline 440 is also connected to the housing 460, and the first gas pipeline 440 is connected to a nitrogen filling system. The nitrogen filling system can supply nitrogen to the top of the housing 460 through the first gas pipeline 440. The nitrogen acts as a protective layer to prevent accidents such as explosions; on the other hand, the nitrogen can seal the liquid surface at the top of the housing 460, thereby preventing exhaust gas from leaking out of the housing 460, reducing the volatilization of exhaust gas, and further ensuring that the exhaust gas can completely enter the exhaust gas emission and treatment system for treatment.

[0036] A gas distributor 441, a nitrogen pressure reducing valve 442, and a nitrogen regulating valve 443 are sequentially installed on the first gas pipeline 440. The nitrogen pressure reducing valve 442 can be a self-operated pressure reducing valve. The self-operated pressure reducing valve is located at the inlet where the first gas pipeline 440 connects to the housing 460. A single-exit valve is initially installed at the outlet of the first gas pipeline 440. The single-exit valve may include a valve body, valve cover, valve core, and spring. When the pressure inside the housing 460 exceeds the external pressure, the single-exit valve automatically opens to release gas and prevent damage to the housing 460. Unlike a breather valve, the single-exit valve can only perform a one-way "exit" operation, primarily used to prevent overpressure inside the housing 460, ensuring safety and energy conservation.

[0037] A gas distribution pipe 466 is provided on the top of the housing 460. A first gas pipeline 440 is connected to the gas distribution pipe 466. Nitrogen gas can be introduced into the top of the housing 460 through the first gas pipeline 440. The nitrogen gas can diffuse from top to bottom in the housing 460 to the catalytic oxidation reaction zone 462 and each electrocatalytic oxidation zone 463 through the gas distribution pipe 466.

[0038] like Figure 1 and Figure 2 As shown, a second gas pipeline 450 is also connected to the housing 460, and the second gas pipeline 450 is connected to the exhaust gas emission and treatment system. The second gas pipeline 450 is used to output the carbon dioxide gas and hydrogen gas generated in the housing 460. The exhaust gas emission and treatment system includes an oxidant liquid spray tower 454, and the second gas pipeline 450 is connected to the oxidant liquid spray tower 454, and an induced draft fan 453 is installed on the pipeline connecting the two. The induced draft fan 453 can introduce the exhaust gas into the second gas pipeline 450 and into the oxidant liquid spray tower 454.

[0039] The oxidant circulation pump 455 at the bottom of the oxidant liquid spray tower 454 pumps the liquid below it to the top of the oxidant liquid spray tower 454 and sprays it downwards from the top, thereby circulating the liquid in the oxidant liquid spray tower 454.

[0040] Specifically, such as Figure 2 As shown, the oxidant liquid spray tower 454 includes a tower body 4541 and a circulation tank 4542. The circulation tank 4542 is located at the bottom of the tower body 4541 and contains an oxidant (such as sodium hypochlorite). The top of the tower body 4541 is provided with an air outlet, and the bottom is provided with an air inlet, which is connected to an induced draft fan 453.

[0041] The top of the tower body 4541 is provided with an upper water distributor, which includes a spray pipe 4543. The spray pipe 4543 is provided with an atomizing nozzle. The spray pipe 4543 is connected to the circulation tank 4542 through an oxidant circulation pump 455.

[0042] The hydrogen and carbon dioxide gases generated in the housing 460 enter the inlet below the tower 4541 through the second gas pipeline 450. The liquid in the circulation pool 4542 can be pumped into the spray pipe 4543 by the oxidant circulation pump 455. The spray pipe 4543 sprays from top to bottom in the tower 4541. The carbon dioxide gas is absorbed by the oxidant after spraying. The gas with carbon dioxide removed is pure hydrogen gas, which can be discharged to the recovery and treatment device for recovery and treatment through the gas outlet at the top of the tower 4541.

[0043] The tower body 4541 is also equipped with catalyst packing 4544, which includes a carrier and a catalyst. The carrier is spherical alumina, and the catalyst is manganese dioxide, iron, or copper, to improve the efficiency of VOC oxidation and degradation and the sterilization effect of the exhaust gas. The COD of the exhaust gas entering the tower body 4541, as well as the small amount of bacteria and viruses it carries, can be further degraded and killed in the tower body 4541, thereby ensuring that the emission gas meets the standards.

[0044] like Figure 1 and Figure 3 As shown, the wastewater treatment device of the present invention also includes a membrane enrichment and separation system 420. The output pipe 465 of the tank 460 is connected to the membrane enrichment and separation system 420. The water treated by the electrocatalytic oxidation primary treatment device 400 enters the membrane enrichment and separation system 420, and the water treated by the membrane enrichment and separation system 420 enters the second intermediate water tank 404.

[0045] The membrane enrichment and separation system 420 serves as a buffer and also performs membrane separation on the water treated in the electrocatalytic oxidation primary treatment unit 400. The permeate membrane further ensures that the effluent meets the standards. The concentrated water retained by the membrane is returned to the electrocatalytic oxidation primary treatment unit 400 for further treatment. The concentrated water retained by the membrane includes lost catalyst, added salts, and incompletely treated wastewater. It is further treated by the organic membrane module 425 to ensure that the produced water meets the standards and to avoid catalyst loss.

[0046] Specifically, the membrane enrichment and separation system 420 includes a first intermediate water tank 421, a microfiltration device 423 connected to the first intermediate water tank 421, and an organic membrane module 425 connected to the microfiltration device 423.

[0047] The first intermediate water tank 421 is connected to the output pipe 465 of the tank body 460 to receive water that has been treated by the electrocatalytic oxidation primary treatment device 400.

[0048] like Figure 3As shown, a booster pump 422 is installed on the pipeline between the first intermediate water tank 421 and the microfiltration device 423, and a high-pressure pump 424 is installed on the pipeline between the microfiltration device 423 and the organic membrane module 425. One output port of the organic membrane module 425 is connected to the second intermediate water tank 404, and the second output port of the organic membrane module 425 is connected to the input port of the organic membrane module 425. A circulating booster pump 426 is also connected between the two, which allows the water to be circulated within the organic membrane module 425. The circulating booster pump maintains a certain momentum energy within the organic membrane module 425. The sodium sulfate and undraught viruses enriched after treatment by the organic membrane module 425 are returned to the input port of the organic membrane module 425 for recycling and further treatment. The third output port of the organic membrane module 425 is also connected to a return pipeline, on which an output regulating valve 428 is installed. The return pipeline is connected to the wastewater inlet 461 at the bottom of the tank 460. The concentrated water retained by the permeate membrane in the organic membrane module 425 is returned to the tank 460 for further treatment. The concentrated water retained by the permeate membrane includes lost catalyst, added salt and incompletely treated wastewater. Therefore, returning it to the tank 460 for further treatment can avoid the loss of catalyst.

[0049] like Figure 1 and Figure 4 As shown, the electrocatalytic oxidation secondary treatment device 600 is connected to the second intermediate water tank 404 via the second wastewater pump 101. Water treated by the organic membrane module 425 enters the electrocatalytic oxidation secondary treatment device 600 for further COD removal.

[0050] like Figure 4 The electrocatalytic oxidation secondary treatment device 600 includes a second anode plate 603, an anode catalyst partition 605, a cation exchange membrane 607, a cathode catalyst partition 608, and a second cathode plate 609 arranged sequentially. The second anode plate 603 and the second cathode plate 609 are respectively connected to the power unit 500. The anode catalyst partition 605 and the cathode catalyst partition 608 are in fluid communication. The inlet of the anode catalyst partition 605 is connected to the second intermediate water tank 404, and the outlet of the cathode catalyst partition 608 is connected to the water production unit 200. More specifically, the outlet of the anode catalyst partition 605 and the inlet of the cathode catalyst partition 608 are in fluid communication through a connecting pipe 611.

[0051] The anode catalyst separator 605 and / or the cathode catalyst separator 608 are filled with catalyst filler 612.

[0052] In one embodiment, both the anode catalyst separator 605 and the cathode catalyst separator 608 are filled with catalyst filler 312. Figure 5As shown, a second anode catalyst chamber 6051 is provided in the anode catalyst partition 605, and a second cathode catalyst chamber 6081 is provided in the cathode catalyst partition 608. The second anode catalyst chamber 6051 and the second cathode catalyst chamber 6081 are respectively filled with catalyst packing 612, and the catalyst packing 612 in the second anode catalyst chamber 6051 occupies at least 90% of the volume of the second anode catalyst chamber 6051, and the catalyst packing 612 in the second cathode catalyst chamber 6081 occupies at least 90% of the volume of the second cathode catalyst chamber 6081.

[0053] In one embodiment, the anode catalyst partition 605 is not filled with catalyst packing 612, while the cathode catalyst partition 608 is filled with catalyst packing 612. For example, the anode catalyst partition 605 may not have an anode catalyst chamber 6051, thus not being filled with catalyst packing 612, or the anode catalyst partition 605 may have an anode catalyst chamber 6051, but the anode catalyst chamber 6051 is not filled with catalyst packing 612. Furthermore, the cathode catalyst partition 608 has a cathode catalyst chamber 6081, which is filled with catalyst packing 612. The catalyst packing 612 in the cathode catalyst chamber 6081 occupies at least 90% of the volume of the cathode catalyst chamber 6081.

[0054] The second anode catalyst chamber 6051 can be a chamber / tank extending along its depth direction on the surface (e.g., its first surface) of the anode catalyst partition 605. For example, the anode catalyst partition 605 has a thickness of 3 mm or more and is used to accommodate the catalyst packing 612. That is, the second anode catalyst chamber 6051 is a chamber / tank extending through the thickness direction of the anode catalyst partition 605.

[0055] like Figure 8 As shown, preferably, the catalyst packing 612 in the second anode catalyst chamber 6051 occupies more than 90% of the volume of the second anode catalyst chamber 6051, that is, the second anode catalyst chamber 6051 is filled or substantially filled by the catalyst packing 612.

[0056] Similarly, the second cathode catalyst chamber 6081 can be a chamber / tank extending along its depth direction on the surface (e.g., its first surface) of the cathode catalyst partition 608. For example, the cathode catalyst partition 608 has a thickness of 3 mm or more and is used to accommodate the catalyst packing 612. That is, the second cathode catalyst chamber 6081 is a chamber / tank extending through the thickness direction of the anode catalyst partition 605.

[0057] like Figure 10As shown, preferably, the catalyst packing 612 in the second anion chamber catalyst chamber 6081 occupies more than 90% of the volume of the second anion chamber catalyst chamber 6081, that is, the second anion chamber catalyst chamber 6081 is filled or substantially filled by the catalyst packing 612.

[0058] A protective mesh 606 and a cation exchange membrane 607 are sequentially disposed between the anode catalyst separator 605 and the cathode catalyst separator 608. The surface of the anode catalyst separator 605 where the second anode catalyst chamber 6051 is disposed (e.g., its first surface) and the surface of the cathode catalyst separator 608 where the second cathode catalyst chamber 6081 is disposed (e.g., its first surface) are disposed back-to-back with each other, that is, both the second anode catalyst chamber 6051 and the second cathode catalyst chamber 6081 are away from the cation exchange membrane 607.

[0059] One protective mesh 606 is located between the anode catalyst separator 605 and the cation exchange membrane 607, and the other protective mesh 606 is located between the cathode catalyst separator 608 and the cation exchange membrane 607. Therefore, the protective mesh 606 can protect the cation exchange membrane 607 to prevent it from being scratched by particles in the catalyst packing 612.

[0060] A cation exchange membrane 607 is located between two protective meshes 606 and is constructed to selectively permeate a second cation. An anode catalyst separator 605 and the cation exchange membrane 607 define a second cation chamber, while the cation exchange membrane 607 and the cathode catalyst separator 608 define a second anion chamber. Therefore, the second cation (H+) in the second cation chamber... + It can pass through the cation membrane 607 and enter the second anion chamber.

[0061] like Figure 8 and Figure 10 As shown, the catalyst packing 612 includes a support and a catalyst. The support is spherical alumina, and the catalyst is manganese dioxide, iron, or copper.

[0062] like Figure 8 and Figure 9 As shown, the anode catalyst partition 605 is also provided with a second anode catalyst flow channel 6052. The second anode catalyst flow channel 6052 includes a second anode catalyst main flow channel 6053 and a plurality of second anode catalyst branch flow channels 6054. The inlet of the second anode catalyst main flow channel 6053 is connected to the second intermediate water tank 404. Each second anode catalyst branch flow channel 6054 is connected to the second anode catalyst main flow channel 6053, and each second anode catalyst branch flow channel 6054 is connected to the second anode catalyst chamber 6051. Water in the second intermediate water tank 404 enters the second anode catalyst chamber 6051 through the second anode catalyst main flow channel 6053 and the plurality of second anode catalyst branch flow channels 6054.

[0063] The second anode catalyst main channel 6053 can be a groove opened on the side of the anode catalyst partition 605 (for example, on the side of the first surface where the second anode catalyst chamber 6051 is located).

[0064] The second anode catalyst branch channel 6054 can be a tank extending in a direction perpendicular to the extension direction of the second anode catalyst main channel 6053. Multiple second anode catalyst branch channels 6054 are sequentially and spaced apart along the extension direction of the second anode catalyst main channel 6053, and are respectively connected to the second anode catalyst main channel 6053 and the second anode catalyst chamber 6051. Therefore, fluid can flow through the second anode catalyst main channel 6053, through each second anode catalyst branch channel 6054, and into the second anode catalyst chamber 6051.

[0065] like Figure 8 and Figure 9 As shown, the second anode catalyst main flow channel 6053 can be respectively opened at the upper side near the anode catalyst partition 605 and at the lower side near the anode catalyst partition 605. A portion of each second anode catalyst branch flow channel 6054 is connected to the second anode catalyst main flow channel 6053 at the upper side near the anode catalyst partition 605, and another portion is connected to the second anode catalyst main flow channel 6053 at the lower side near the anode catalyst partition 605.

[0066] like Figure 10 and Figure 11 As shown, a second cathode catalyst flow channel 6082 is also provided in the cathode catalyst partition 608. The second cathode catalyst flow channel 6082 includes a second cathode catalyst main flow channel 6083 and multiple second cathode catalyst branch flow channels 6084. The second cathode catalyst main flow channel 6083 is connected to the water production unit 200. Each second cathode catalyst branch flow channel 6084 is connected to the second cathode catalyst main flow channel 6083, and each second cathode catalyst branch flow channel 6084 is connected to the second cathode catalyst chamber 6081. The water generated in the second cathode catalyst chamber 6081 enters the water production unit 200 through the multiple second cathode catalyst branch flow channels 6084 and the second cathode catalyst main flow channel 6083.

[0067] The second cathode catalyst main channel 6083 can be a groove opened on the side of the cathode catalyst partition 608 (for example, on the side of the first surface where the second cathode catalyst chamber 6081 is located).

[0068] The second cathode catalyst branch channel 6084 can be a tank extending in a direction perpendicular to the extension direction of the second cathode catalyst main channel 6083. Multiple second cathode catalyst branch channels 6084 are sequentially and spaced apart in the extension direction of the second cathode catalyst main channel 6083, and are respectively connected to the second cathode catalyst main channel 6083 and the second cathode catalyst chamber 6081. Therefore, fluid can flow through the second cathode catalyst main channel 6083, through each second cathode catalyst branch channel 6084, and into the second cathode catalyst chamber 6081.

[0069] like Figure 10 and Figure 11 As shown, the second cathode catalyst main flow channel 6083 can be respectively opened at the upper side near the cathode catalyst partition 608 and at the lower side near the cathode catalyst partition 608. A portion of each second cathode catalyst branch flow channel 6084 communicates with the second cathode catalyst main flow channel 6083 at the upper side near the cathode catalyst partition 608, and another portion communicates with the second cathode catalyst main flow channel 6083 at the lower side near the cathode catalyst partition 608.

[0070] like Figure 4 , Figure 8 and Figure 10 As shown, the second anode catalyst main channel 6053 and the second cathode catalyst main channel 6083 are connected by a connecting pipe 611. Therefore, water in the second intermediate water tank 404 is pumped by the second wastewater pump 101 into the second anode catalyst main channel 6053 in the anode catalyst partition 605, and flows into the second anode catalyst chamber 6051 via each second anode catalyst branch channel 6054, and then flows to the second cathode catalyst chamber 6081 via the connecting pipe 611. The wastewater undergoes a reaction in the second anode catalyst chamber 6051 and the second cathode catalyst chamber 6081 to remove COD from the wastewater. The treated water can then be pumped to the water treatment unit 200.

[0071] More specifically, the anode catalyst main channel 6053 located above the anode catalyst partition 605 is connected to the cathode catalyst main channel 6083 located below the cathode catalyst partition 608. The anode catalyst main channel 6053 located below the anode catalyst partition 605 is connected to the second intermediate water tank 404, and the cathode catalyst main channel 6083 located above the cathode catalyst partition 608 is connected to the water production unit 200. That is to say, the upper outlet of the second anode catalyst main channel 6053 and the lower inlet of the second cathode catalyst main channel 6083 are connected through a connecting pipe 611. The second intermediate water tank 404 is connected to the lower inlet of the second anode catalyst main channel 6053 through a pipe, and the upper inlet of the second cathode catalyst main channel 6083 is connected to the water production unit 200 through a pipe. Therefore, wastewater enters from the lower part of the second anode catalyst main channel 6053 and flows upward through the second anode catalyst chamber 6051 via each second anode catalyst branch channel 6054, where it can react under the action of the catalyst. Correspondingly, the water after reaction in the second anode chamber enters from the upper outlet of the second anode catalyst main channel 6053 into the lower inlet of the second cathode catalyst main channel 6083 and flows upward through each second cathode catalyst branch channel 6084 via the second cathode catalyst chamber 6081, where it can react under the action of the catalyst. This increases the path of wastewater through the second anode catalyst chamber 6051 and the second cathode catalyst chamber 6081, and increases the residence time in both chambers, allowing sufficient reaction time and thus improving the COD removal rate.

[0072] In an embodiment where the anode catalyst partition 605 does not have an anode catalyst chamber 6051, the thickness of the anode catalyst partition 605 can be correspondingly thinner, for example, it can be 1 mm. Furthermore, the anode catalyst branch channels 6054 can be omitted, and the anode chamber inlet and outlet can be achieved solely through the anode catalyst main channel 6053 connected to the second intermediate water tank 404 and the fourth main channel located below the cathode catalyst partition 608.

[0073] The second anode plate 603 and the second cathode plate 609 are made of the same material, for example, both are made of titanium plates coated with a precious metal. The precious metal can be, for example, ruthenium or iridium, or other precious metals.

[0074] like Figure 5As shown, gaskets 602 and mesh screens 604 are provided on the side of the anode catalyst separator 605 away from the cation exchange membrane 607 and the side of the cathode catalyst separator 608 away from the cation exchange membrane 607, respectively. Furthermore, the electrocatalytic oxidation secondary treatment device also includes an anode end plate 601 and a cathode end plate 610. The anode end plate 601 is located on the side of the anode catalyst separator 605 away from the cation exchange membrane 607, and the cathode end plate 610 is located on the side of the cathode catalyst separator 608 away from the cation exchange membrane 607. Gaskets 602 are respectively provided on the side of the anode end plate 601 near the anode catalyst separator 605 and the side of the cathode end plate 610 near the cathode catalyst separator 608.

[0075] In other words, the electrocatalytic oxidation secondary treatment device is sequentially equipped with: anode plate 601, gasket 602 (first gasket), second anode plate 603, separator 604 (first separator), gasket 602 (second gasket), anode catalyst separator 605, protective mesh 606 (first protective mesh), cation membrane 607, protective mesh 606 (second protective mesh), cathode catalyst separator 608, gasket 602 (third gasket), separator 604 (second separator), second cathode plate 609, gasket 602 (fourth gasket), and cathode plate 610.

[0076] Gasket 602 serves as a sealing connection. Gasket 602 on one side of the anode catalyst partition 605 abuts against the anode catalyst partition 605, thereby retaining the catalyst packing 612 within the anode catalyst chamber 6051. Similarly, gasket 602 on one side of the cathode catalyst partition 608 abuts against the cathode catalyst partition 608, thereby retaining the catalyst packing 612 within the cathode catalyst chamber 6081.

[0077] Therefore, it can be seen that the catalyst packing 612 is contained in the second anode chamber catalyst chamber 6051 of the anode catalyst partition 605. A protective net 606 is provided on the side of the anode catalyst partition 605 near the cation membrane 607, and a gasket 602 is provided on the side away from the cation membrane 607. Thus, the gasket 602 and the protective net 606 can seal the catalyst packing 612 in the second anode chamber catalyst chamber 6051 from both sides of the anode catalyst partition 605. Furthermore, the protective net 606 has a mesh structure with openings, so that the wastewater can react in the second anode chamber defined by the anode catalyst partition 605 and the cation membrane 607.

[0078] Similarly, the gaskets 602 and protective nets 606 on both sides of the cathode catalyst partition 608 can seal the catalyst packing 612 in the second anion chamber catalyst chamber 6081 from both sides of the cathode catalyst partition 608, so that the wastewater can be reacted in the second anion chamber defined by the cathode catalyst partition 608 and the cation membrane 607.

[0079] The second anode plate 603 and the second cathode plate 609 are respectively connected to the positive and negative terminals of the power unit 500, which can be, for example, a DC power supply. Figure 6 As shown, the second anode plate 603 is provided with two or more anode plate terminals 6031, which are connected to the positive terminal of the power unit 500. Figure 4 As shown, the second cathode plate 609 is provided with two or more cathode plate terminals 6091, which are connected to the negative terminal of the power unit 500.

[0080] The anode plate 601 and cathode plate 610 are used to press-fit the above components together. The components can be pressed together by the connecting parts that pass through them to form a sealed whole, allowing fluid to flow therein.

[0081] Therefore, it can be seen that the anode catalyst separator 605 and the cation membrane 607 define the second cation chamber where the oxidation reaction occurs, and the cation membrane 607 and the cathode catalyst separator 608 define the second anion chamber where the reduction reaction occurs.

[0082] After connecting the second anode plate 603 and the second cathode plate 609 to a DC power supply, hydrogen gas can be generated in the second cathode chamber; oxygen gas and a large number of hydroxyl radicals (·OH) can be generated in the second anode chamber. Hydroxyl radicals have strong oxidizing properties; bacteria and viruses in wastewater (such as medical wastewater) can be killed by hydroxyl oxidation. Furthermore, because the anode catalyst partition 605 is filled with catalyst packing 612, under the action of the catalyst, the wastewater undergoes a catalytic oxidation reaction at the interface of the second anode plate 603. The generated hydroxyl radicals and the catalyst in the catalyst packing 612 synergistically act on the organic matter, carrying out continuous oxidation and decomposition. Ultimately, the organic matter is oxidized and decomposed into carbon dioxide and water by hydroxyl radicals, and substances such as ammonia nitrogen are oxidized and removed. The reaction formula in the second anode chamber is 2H₂O - 2e⁻ - →2·OH+2H + .

[0083] The second cation (H) in the second cation chamber + The oxygen produced in the second cation chamber can pass through the cation membrane 607 into the second anion chamber. The oxygen is carried into the second anion chamber along with the wastewater through the connecting pipe 611. In the second anion chamber, under the action of the catalyst coated on the second cathode plate, the oxygen undergoes an O2 reduction reaction to produce hydrogen peroxide (H2O2) or HO2. - Hydrogen peroxide and COD in wastewater undergo a highly efficient oxidative degradation reaction under the action of a catalyst in the second anion chamber, further oxidizing and degrading undegraded organic matter.

[0084] Therefore, in this invention, by connecting the anode catalyst partition 605 and the cathode catalyst partition 608 through the connecting pipe 611, the oxygen generated in the second anode chamber can flow with the wastewater from the second anode chamber to the second cathode chamber via the connecting pipe 611. This allows a reduction reaction to occur in the second cathode chamber to generate hydrogen peroxide, thereby achieving the purpose of COD degradation. Therefore, this invention eliminates the need to actively add oxygen to the second cathode chamber; instead, it directly utilizes the oxygen generated in the second anode chamber, resulting in higher treatment efficiency and lower cost.

[0085] In existing technologies, electrolysis devices such as H-type electrolytic cells typically separate the second anion chamber and the second cation chamber using an ion exchange membrane. While this type of electrolysis device has a relatively simple structure, it suffers from limited mass transfer (especially the difficulty of oxygen diffusion to the second cathode). This invention, by connecting the anode catalyst partition 605 and the cathode catalyst partition 608, allows wastewater to carry oxygen generated at the second anode as it flows from the anode catalyst partition 605 to the cathode catalyst partition 608. This oxygen then diffuses into the second anion chamber catalyst chamber 6081 and the second anion chamber via the main flow channel 6083 and the branch flow channel 6084 of the second cathode catalyst. Therefore, this invention enables oxygen to diffuse easily, conveniently, and efficiently into the second anion chamber, facilitating efficient reactions within the second anion chamber.

[0086] In one specific embodiment, the wastewater in the second intermediate water tank 404 has a conductivity of 300 μS / cm, a COD of 21 ppm, and an ammonia nitrogen concentration of 15 ppm. The influent flow rate from the second intermediate water tank 404 to the anode catalyst separator 605 is 250 L / h. After the wastewater flows into the anode catalyst separator 605 (the area of ​​the cation exchange membrane 607 is 0.5 m²), 2 The second anode plate 603 and the second cathode plate 609 are connected to the positive and negative terminals of the power unit 500, respectively. When the voltage of the power unit 500 (DC power supply) is 6V and the current is 3.8A, the COD of the effluent from the anode chamber is 9.5ppm and the ammonia nitrogen concentration is 7.2ppm; the COD of the effluent from the cathode chamber is 0.0ppm and the ammonia nitrogen concentration is only 1.2ppm. Therefore, it can be seen that the COD removal rate reaches 100%. In addition, in this embodiment, the power consumption per ton of water is about 0.09 kWh, which can greatly save energy.

[0087] The wastewater treatment process of the electrocatalytic oxidation secondary treatment device 300 of the present invention is as follows: The second anode plate 603 and the second cathode plate 609 are connected to the positive and negative terminals of a DC power supply, respectively. The second anode chamber generates hydroxyl groups and oxygen. Water in the second intermediate water tank 404 is pumped into the anode catalyst partition 605 by the second wastewater pump 101. The wastewater undergoes an oxidation reaction in the second anode chamber defined by the anode catalyst partition 605 and the cation exchange membrane 607. The COD in the wastewater is efficiently oxidized and degraded by hydroxyl groups under the action of the catalyst packing 612 in the anode catalyst partition 605. COD is oxidized and degraded into carbon dioxide and water, and substances such as ammonia nitrogen are oxidized into nitrogen gas. The wastewater flows through the second anode chamber and enters the second anion chamber defined by the cation exchange membrane 607 and the cathode catalyst partition 608 through the connecting pipe 611. The oxygen carried in the wastewater reacts with water to produce hydrogen peroxide. The hydrogen peroxide reacts with the catalyst packing 612 in the cathode catalyst partition 608 to further degrade COD and obtain water that meets the requirements. The product water in the cathode catalyst partition 608 can be fed into the product water unit 200.

[0088] In other embodiments of the present invention, where the anode catalyst partition 605 is not filled with catalyst filler 612 and the cathode catalyst partition 608 is filled with catalyst filler 612, a pH adjustment device is also connected to the water inlet end of the connecting pipe 611 near the cathode catalyst partition 608. The pH adjustment device allows the addition of acid or alkali to the second anion chamber to change the acid-base environment of the electrolyte in the second anion chamber. In this embodiment, the catalyst filler 312 includes a support and a catalyst; the support is spherical alumina, and the catalyst is manganese dioxide, iron, or copper to improve the COD oxidation and degradation efficiency. The catalyst filler 312 and the catalyst filler 4544 can be the same catalyst filler or different catalyst fillers.

[0089] Because the reaction in the second cathode chamber is essentially that oxygen gains electrons on the surface of the second cathode plate 609 and is reduced to generate hydrogen peroxide ions (HO2). - The process involves the production of hydrogen peroxide (H2O2). This reaction can proceed via a two-electron or four-electron pathway.

[0090] For example, NaOH or KOH solution can be added to the second anion chamber to create an alkaline environment. In this case, the reaction in the second anion chamber follows a two-electron pathway (the target reaction): O₂ + H₂O + 2e⁻ - → HO2 - + OH - Or, via the four-electron pathway (competitive reaction): O₂ + 2H₂O + 4e - → 4OH - .

[0091] The aforementioned two-electron oxygen reduction reaction is kinetically more favorable in an alkaline medium, and by placing the second anion chamber in an alkaline environment, the H2O2 produced in the second anion chamber can be relatively stable in an alkaline environment (as shown by HO2). - (Form exists).

[0092] Alternatively, H2SO4 solution can be added to the second anion chamber to create an acidic environment. In this case, the reaction in the second anion chamber follows a two-electron pathway (the target reaction): O2 + 2H+ + + 2e - → H2O2; or the four-electron pathway (competitive reaction): O2 + 4H + + 4e - → 2H2O.

[0093] In an acidic environment, H₂O₂ can be directly produced, so the product does not require conversion, and some catalysts are more stable in acidic conditions. However, the kinetics of the above two-electron oxygen reduction reaction are generally slow, and the requirements for the catalyst are more stringent.

[0094] Alternatively, the second anion chamber can be placed in a neutral solution, for example, by adding Na2SO4, KHCO3, etc., which would be more suitable for various applications.

[0095] The second cathode plate 609 is coated with a noble metal catalyst (such as ruthenium, iridium, etc.), which can greatly enhance the two-electron O2 reduction reaction and suppress the four-electron pathway (water generation) to the greatest extent. When the wastewater flows through the cation chamber, the oxygen generated is carried into the anion chamber, where a reduction reaction occurs to generate hydrogen peroxide. The hydrogen peroxide reacts with the catalyst packing 612 in the cathode catalyst separator 608 to efficiently oxidize and degrade COD to obtain product water that meets the requirements.

[0096] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A wastewater treatment system with high organic matter content, characterized in that, The system includes a multi-stage treatment device, which comprises an electrocatalytic oxidation primary treatment device and an electrocatalytic oxidation secondary treatment device. Wastewater treated by the electrocatalytic oxidation primary treatment device enters the electrocatalytic oxidation secondary treatment device for COD removal. The electrocatalytic oxidation primary treatment device includes a housing, a catalytic oxidation reaction zone and an electrocatalytic oxidation zone disposed within the housing. The catalytic oxidation reaction zone is located at the top layer of the housing and is filled with packing material. The electrocatalytic oxidation zone is located below the catalytic oxidation reaction zone and is provided with n sets of parallel electrode plates. Each set of electrode plates includes a first anode plate and a first cathode plate disposed at intervals, and packing material is disposed between each first anode plate and the first cathode plate.

2. The organic wastewater treatment system according to claim 1, characterized in that, The surface of the first anode plate is coated with a precious metal coating, and the first cathode plate is a nickel plate.

3. The high-organic-content wastewater treatment system according to claim 1 or 2, characterized in that, The distance between the first anode plate and the first cathode plate is 20mm-60mm, and the current density of the electrocatalytic oxidation primary treatment device is 30A / m. 2 -80A / m 2 .

4. The high-organic-content wastewater treatment system according to claim 1 or 2, characterized in that, The filler is a loose, porous granular structure that supports a catalyst, and the catalyst is manganese dioxide, iron, copper, or a precious metal.

5. The high-organic-content wastewater treatment system according to claim 1 or 2, characterized in that, The electrocatalytic oxidation zone is configured with at least two layers. Each layer of the electrocatalytic oxidation zone is provided with a turbulent water distributor that extends along the length of the tank and covers the entire length of the tank, for uniformly distributing water to each layer of the electrocatalytic oxidation zone.

6. The high-organic-content wastewater treatment system according to claim 1 or 2, characterized in that, It also includes a membrane enrichment and separation system, which comprises: The first intermediate water tank is connected to the output pipe of the tank body to receive water that has been treated by the electrocatalytic oxidation primary treatment device. A microfiltration device, which is connected to the first intermediate water tank; An organic membrane module, which is connected to the microfiltration device; The organic membrane module has one output port connected to a second intermediate water tank, which is connected to the electrocatalytic oxidation secondary treatment device; the organic membrane module has a second output port connected to an input port; and the organic membrane module has a third output port connected to a return pipe, which is connected to a wastewater inlet at the bottom of the container.

7. The high-organic-content wastewater treatment system according to claim 6, characterized in that, The electrocatalytic oxidation secondary treatment device includes a second cation chamber and a second anion chamber, wherein the second cation chamber is defined by an anode catalyst separator and a cation membrane, and the second anion chamber is defined by the cation membrane and a cathode catalyst separator; Water from the second intermediate water tank enters the anode catalyst partition and undergoes an oxidation reaction in the second anode chamber. Wastewater flows through the second anode chamber and then into the second anion chamber.

8. The high-organic-content wastewater treatment system according to claim 7, characterized in that, The outlet of the anode catalyst separator and the inlet of the cathode catalyst separator are connected by a connecting pipe. Wastewater flows through the second anode chamber and can then enter the second cathode chamber through the connecting pipe to react.

9. The high-organic-content wastewater treatment system according to claim 7, characterized in that, The anode catalyst separator and / or the cathode catalyst separator are filled with catalyst packing material, which includes a support and a catalyst. The support is spherical alumina, and the catalyst is manganese dioxide, iron, or copper.

10. The high-organic-content wastewater treatment system according to claim 7, characterized in that, The electrocatalytic oxidation secondary treatment device further includes a second anode plate located on the side of the anode catalyst separator away from the cation membrane and a second cathode plate located on the side of the cathode catalyst separator away from the cation membrane. The second anode plate and the second cathode plate are made of the same material, both of which are made of titanium plates coated with precious metals.

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