Membrane electrode sewage treatment device with in-situ cleaning function and treatment method thereof

Abstract

The invention relates to a membrane electrode sewage treatment device with an in-situ cleaning function and a treatment method thereof. The membrane electrode sewage treatment device comprises a reaction tank, and an anode and a membrane assembly cathode are arranged in the reaction tank; the membrane electrode sewage treatment device further comprises a power supply device, a positive electrode of the power supply device is electrically connected with the anode, and a negative electrode of the power supply device is electrically connected with the membrane component cathode; a water outlet is formed in the top of the shell of the reaction tank and is communicated with a membrane component outlet adopted by the membrane component cathode. By introducing the electric cleaning technology and improving the coupling mode and electric field distribution of the electrode and the membrane assembly, in-situ cleaning of the membrane assembly is achieved, pollutants accumulated on the membrane surface can be effectively removed, generation of by-products is reduced, and the influence of membrane pollution on membrane flux is reduced, so that the service life of the membrane assembly is prolonged, the operation stability of the system is improved, and the service life of the membrane assembly is prolonged. And high efficiency and environmental friendliness of the cleaning process are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, and relates to a sewage treatment device and a treatment method thereof, and particularly relates to a membrane electrode sewage treatment device with an in-situ cleaning function and a treatment method thereof. Background Art

[0002] In the field of sewage treatment, the membrane bioreactor (MBR) technology has been widely used because it can effectively treat and purify wastewater. However, the problem of membrane fouling seriously restricts the further development and wide application of MBR technology. Membrane fouling not only reduces the membrane flux, but also increases the operating cost and shortens the service life of the membrane. To solve the problem of membrane fouling, researchers have proposed a variety of cleaning and regeneration technologies, including physical cleaning, chemical cleaning, and combined cleaning technologies.

[0003] Physical cleaning methods include backwashing, air-water scrubbing, and ultrasonic cleaning, etc., which remove pollutants on the membrane surface by applying physical forces. These methods can usually only remove reversible fouling, and have limited effects on irreversible fouling. Chemical cleaning dissolves and removes pollutants through chemical agents, but this method may damage the membrane material, and the use and treatment of chemical agents also increase the operating cost and environmental burden.

[0004] To further improve the cleaning efficiency and reduce the damage to the membrane material, an electro-membrane bioreactor (EMBR) combining electrochemical technology has been developed in recent years. The EMBR technology removes pollutants on the membrane by applying an electric field on the membrane surface and using redox substances generated by electrochemical reactions. This method can not only effectively reduce membrane fouling, but also reduce the frequency of chemical cleaning to a certain extent.

[0005] Currently, integrating the electrochemical cleaning technology and the membrane separation technology into one device to achieve online electro-cleaning of the membrane module is an important research direction. For example, CN108217917A discloses an electrochemical membrane bioreactor sewage processor, which realizes the combination of electrochemical and membrane separation technologies by setting electrodes and membrane modules in the treatment tank, effectively alleviating the problem of membrane fouling. However, this device may face problems such as precipitation particles clogging the membrane pores and changes in the pH value of the solution during the electrochemical operation in practical applications.

[0006] In addition, CN107459106A discloses an electrochemical-membrane separation water treatment device, which performs electrochemical treatment on wastewater by setting electrodes and membrane modules in the reaction tank. However, the precipitation particles generated during the electrochemical treatment are likely to deposit on the membrane surface, resulting in a decrease in membrane flux. At the same time, the pH value change during the electrochemical reaction process may also affect the existence form of ions in water, thereby affecting the water treatment effect.

[0007] However, although the EMBR technology has shown potential in suppressing membrane fouling, there are still some technical challenges at present. The coupling design of the electrode and the membrane module is complex, and it is difficult to uniformly control the distribution and intensity of the electric field, resulting in uneven cleaning effects. In addition, by-products may be generated during the electrochemical reaction process, posing potential risks to the stability of the system and environmental safety. Therefore, there is still room for optimization in existing EMBR systems in practical applications, and there is an urgent need for improvement and innovation to improve their cleaning efficiency and operational stability and reliability. Summary of the Invention

[0008] To solve the above technical problems, the present invention provides a membrane electrode sewage treatment device with in-situ cleaning function and its treatment method. By introducing an electro-cleaning technology, in-situ cleaning of the membrane module is realized, effectively removing the pollutants accumulated on the membrane surface, reducing the impact of membrane fouling on the membrane flux, thereby extending the service life of the membrane module and improving the operational stability of the system; by improving the coupling method of the electrode and the membrane module and the electric field distribution, the uniformity of the cleaning effect is enhanced, and the by-products that may be generated during the electrochemical reaction process are reduced, ensuring the high efficiency and environmental protection of the cleaning process.

[0009] To achieve this purpose, the present invention adopts the following technical solutions:

[0010] In the first aspect, the present invention provides a membrane electrode sewage treatment device with in-situ cleaning function. The membrane electrode sewage treatment device includes a reaction tank, and an anode and a membrane module cathode are arranged in the reaction tank; the membrane electrode sewage treatment device further includes a power supply device, the positive electrode of the power supply device is electrically connected to the anode, and the negative electrode of the power supply device is electrically connected to the membrane module cathode; a water outlet is arranged at the top of the housing of the reaction tank, and the water outlet is communicated with the membrane module outlet of the membrane module cathode.

[0011] By introducing the electro-cleaning technology, the present invention can effectively remove the pollutants accumulated on the membrane surface. Under the action of the electric field, the electrostatic repulsion between the membrane module cathode and the sludge flocs with the same negative charge is enhanced, alleviating membrane fouling; and gas is generated on the surface of the membrane module cathode, and the scouring effect of the bubbles is utilized to realize in-situ cleaning of the membrane module, improving the uniformity of the cleaning effect, and reducing the by-products that may be generated during the electrochemical reaction process, ensuring the high efficiency and environmental protection of the cleaning process.

[0012] Preferably, the anode is graphite or carbon felt.

[0013] Using graphite or carbon felt as the anode can, on the one hand, reduce the cost of the entire device, and on the other hand, ensure the operational stability of the entire device and extend the service life of the membrane electrode on the basis of ensuring the sewage treatment effect.

[0014] Preferably, the number of anodes ≥ 1, for example, it can be 1, 2, 3 or 4, but not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0015] Preferably, the membrane module used for the cathode of the membrane module is a conductive membrane.

[0016] Preferably, the conductive membrane is a microfiltration membrane, an ultrafiltration membrane or a nanofiltration membrane.

[0017] Preferably, the material of the conductive membrane is stainless steel or titanium metal.

[0018] Preferably, the conductive membrane is a porous membrane.

[0019] Preferably, the filtration accuracy of the membrane module is 0.2 μm - 0.25 μm, for example, it can be 0.2 μm, 0.22 μm, 0.24 μm or 0.25 μm, but not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0020] Preferably, the number of cathodes of the membrane module ≥ 1, for example, it can be 1, 2, 3 or 4, but not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0021] Preferably, a water inlet is provided at the bottom of the shell of the reaction tank.

[0022] Preferably, a step joint is welded to the outlet of the membrane module, and the step joint is connected to the water outlet pipe of the water outlet.

[0023] Preferably, the material of the step joint is stainless steel.

[0024] Preferably, an external device is provided on the pipeline of the water outlet pipe, and the external device includes an external TMP recorder and an external water outlet pump.

[0025] Preferably, the external water outlet pump is connected to a time relay.

[0026] Preferably, the external water outlet pump is a basic peristaltic pump.

[0027] Preferably, the power supply device is a DC power supply.

[0028] In a second aspect, the present invention provides a sewage treatment method. The sewage treatment method uses the membrane electrode sewage treatment device described in the first aspect, and includes the following steps:

[0029] Sewage is introduced into the reaction tank, and under the power supply state, the sewage is filtered through the cathode of the membrane module until the water quality of the effluent meets the standard and then discharged.

[0030] Preferably, the filtration process includes a cyclic first power supply state and a second power supply state.

[0031] Preferably, the voltage of the first power supply state is 0.2V - 0.6V, and the time is 57min - 59min. For example, the voltage of the first power supply state can be 0.2V, 0.3V, 0.4V, 0.5V or 0.6V, and the time of the first power supply state can be 57min, 57.5min, 58min, 58.5min or 59min. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0032] Preferably, the voltage of the second power supply state is 8V - 12V, and the time is 1min - 3min. For example, the voltage of the second power supply state can be 8V, 9V, 10V, 11V or 12V, and the time of the second power supply state can be 1min, 1.5min, 2min, 2.5min or 3min. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0033] By further regulating the voltage and time of the second power supply state, the present invention can further improve the treatment effect of the sewage treatment device, increase the service life of the sewage treatment device, and improve the operation stability of the system. Within the preferred voltage and time range, the sewage treatment device has good treatment effect, long service life, and high operation stability of the treatment device system.

[0034] Preferably, the transmembrane pressure difference of the second power supply state is 35kPa - 40kPa. For example, it can be 35kPa, 36kPa, 37kPa, 38kPa, 39kPa or 40kPa. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0035] Preferably, the discharge includes a cyclic discharge state and a stop state.

[0036] Preferably, the flow rate of the discharge state is 30LMH - 50LMH, and the time is 6min - 8min. For example, the flow rate of the discharge state can be 30LMH, 35LMH, 40LMH, 45LMH or 50LMH, and the time of the discharge state can be 6min, 6.5min, 7min, 7.5min or 8min. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0037] Preferably, the time of the stop state is 2min - 4min. For example, it can be 2min, 2.5min, 3min, 3.5min or 4min. However, it is not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0038] Compared with the prior art, the present invention has at least the following beneficial effects:

[0039] (1) Significant energy-saving effect: Since the electric cleaning device of the present invention can perform cleaning in real time during the operation of the system without the need for frequent shutdown for physical or chemical cleaning, it can greatly reduce the system downtime and save energy consumption. This continuous cleaning process also reduces the need for external chemical agents, further reducing the operating cost of the system.

[0040] (2) Easy operation and low maintenance cost: The cleaning process of the device is managed by an automatic control system, which is easy to operate and does not require specialized personnel to perform complex operations. This not only reduces the difficulty of operation, but also reduces the errors and inconsistencies that may be caused by manual operation. At the same time, due to the optimized design of the cleaning process, membrane fouling can be effectively controlled, reducing the replacement frequency of membrane components, thereby significantly reducing the maintenance cost of the system.

[0041] (3) Strong adaptability and wide application: The electric cleaning device of the present invention is flexible in design and can adapt to different types of membrane components and water treatment systems of different sizes. Whether it is treating municipal sewage, industrial wastewater or special wastewater (such as oily wastewater, high-salt wastewater, etc.), the device can achieve excellent cleaning effects. In addition, it can also adjust parameters according to different pollutant types and water quality conditions to ensure that ideal cleaning effects can be achieved in various application scenarios.

[0042] (4) Extending membrane life and reducing environmental impact: Due to the effectiveness of the present invention in reducing membrane pollution, the life of the membrane assembly can be significantly extended, thereby reducing the consumption and replacement frequency of membrane materials; this not only helps to reduce operating costs, but also reduces the burden of waste membrane materials on the environment; at the same time, the generation of by-products during the electrochemical cleaning process is effectively controlled, reducing the risk of secondary pollution to water quality and the surrounding environment.

[0043] (5) Improved water treatment efficiency: By reducing membrane fouling, the present invention can maintain a high water flux and improve the overall water treatment efficiency. This is particularly important for systems that treat high-load wastewater, and helps to achieve efficient wastewater treatment with a smaller footprint and lower operating costs, thereby meeting strict emission standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a schematic structural diagram of a membrane electrode wastewater treatment device with an in-situ cleaning function provided in Example 1 of the present invention;

[0045] Figure 2 This is a rendering of the sewage treatment method provided in Application Example 1 of the present invention;

[0046] Among them, 1 - Anode electrode; 2 - Anode electrode; 3 - Reaction tank; 4 - Membrane module cathode; 5 - Power supply device. Detailed implementation mode

[0047] The technical solution of the present invention will be further described below in conjunction with the drawings and through specific implementation modes. However, the following examples are only simple examples of the present invention and do not represent or limit the scope of the patent protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0048] Example 1

[0049] This example provides a membrane electrode sewage treatment device with an in-situ cleaning function. The membrane electrode sewage treatment device is as shown in Figure 1 and includes a reaction tank 3, in which an anode electrode 1, an anode electrode 2 and a membrane module cathode 4 are arranged;

[0050] Both the anode electrode 1 and the anode electrode 2 are graphite electrodes, and the membrane module cathode 4 is a titanium metal conductive ultrafiltration membrane with a filtration accuracy of 0.22 μm;

[0051] The membrane electrode sewage treatment device further includes a power supply device 5. The power supply device 5 is a DC power supply. The positive pole of the power supply device is electrically connected to the anode, and the negative pole of the power supply device is electrically connected to the membrane module cathode;

[0052] The top of the shell of the reaction tank is provided with a water outlet, which is communicated with the membrane module outlet of the membrane module cathode. A TMP recorder and a basic peristaltic pump are arranged on the water outlet pipe of the water outlet, and the peristaltic pump is connected to a time relay;

[0053] Among them, the TMP recorder, the basic peristaltic pump and the time relay are not shown in the figure.

[0054] Figure 1 is a schematic structural diagram of the membrane electrode sewage treatment device with an in-situ cleaning function provided in Example 1 of the present invention, in which, 1 - Anode electrode; 2 - Anode electrode; 3 - Reaction tank; 4 - Membrane module cathode; 5 - Power supply device.

[0055] Example 2

[0056] This example provides a membrane electrode sewage treatment device with an in-situ cleaning function. The membrane electrode sewage treatment device includes a reaction tank 3, in which an anode electrode 1 and a membrane module cathode 4 are arranged;

[0057] The anode electrode 1 is a carbon felt electrode, and the membrane module cathode 4 is a stainless steel conductive ultrafiltration membrane with a filtration accuracy of 0.2 μm;

[0058] The membrane electrode sewage treatment device further includes a power supply device 5, the power supply device 5 is a DC power supply, the positive electrode of the power supply device is electrically connected to the anode, and the negative electrode of the power supply device is electrically connected to the cathode of the membrane module;

[0059] A water outlet is provided at the top of the housing of the reaction tank, the water outlet is communicated with the membrane module outlet of the cathode of the membrane module, a TMP recorder and a basic peristaltic pump are arranged on the water outlet pipe of the water outlet, and the peristaltic pump is connected to a time relay.

[0060] Example 3

[0061] This example provides a membrane electrode sewage treatment device with an in-situ cleaning function. The membrane electrode sewage treatment device includes a reaction tank 3, and an anode electrode 1, an anode electrode 2 and a membrane module cathode 4 are arranged in the reaction tank;

[0062] The anode electrode 1 is a graphite electrode, the anode electrode 2 is a carbon felt electrode, and the membrane module cathode 4 is a titanium metal conductive ultrafiltration membrane with a filtration accuracy of 0.25 μm;

[0063] The membrane electrode sewage treatment device further includes a power supply device 5, the power supply device 5 is a DC power supply, the positive electrode of the power supply device is electrically connected to the anode, and the negative electrode of the power supply device is electrically connected to the cathode of the membrane module;

[0064] A water outlet is provided at the top of the housing of the reaction tank, the water outlet is communicated with the membrane module outlet of the cathode of the membrane module, a TMP recorder and a basic peristaltic pump are arranged on the water outlet pipe of the water outlet, and the peristaltic pump is connected to a time relay.

[0065] Example 4

[0066] The difference between this example and Example 1 is only that, except for removing the anode electrode 2 and only using the anode electrode 1, other devices and their connection relationships are the same as those in Example 1.

[0067] Example 5

[0068] The difference between this example and Example 1 is only that, except for replacing the anode 2 with an aluminum metal anode, other devices and their connection relationships are the same as those in Example 1.

[0069] Example 6

[0070] The difference between this example and Example 1 is only that, except for replacing the anode electrode 1 and the anode electrode 2 with aluminum metal anodes respectively, other devices and their connection relationships are the same as those in Example 1.

[0071] Comparative Example 1

[0072] The difference between this comparative example and Example 1 is only that, except that the titanium metal conductive ultrafiltration membrane of the cathode 4 of the membrane module is replaced with a titanium metal cathode, other devices and their connection relationships are the same as those in Example 1.

[0073] Application Example 1

[0074] This application example provides a sewage treatment method, which uses the membrane electrode sewage treatment device with in-situ cleaning function provided in Example 1. The treatment method includes the following steps:

[0075] Sewage with an initial sludge concentration of 7 g / L is introduced into the reaction tank 3 from the water inlet. Under the power supply state, the sewage is filtered through the cathode of the membrane module until the water quality of the effluent meets the standard and then discharged.

[0076] The filtration treatment includes a cyclic first power supply state and a second power supply state;

[0077] The voltage of the first power supply state is 0.4 V and the time is 59 min;

[0078] The voltage of the second power supply state is 10 V and the time is 1 min;

[0079] The discharge includes a cyclic discharge state and a stop state;

[0080] The time of the discharge state is 8 min;

[0081] The flux of the discharge state is 50 LMH;

[0082] The time of the stop state is 2 min.

[0083] Figure 2 It is the effect diagram of the sewage treatment method provided in Application Example 1 of the present invention. It can be seen from the figure that the membrane fouling cycle corresponding to this application example is 18 days, and under the second power supply state, the transmembrane pressure difference is stable at 38 kPa.

[0084] Application Example 2

[0085] This application example provides a sewage treatment method, which uses the membrane electrode sewage treatment device with in-situ cleaning function provided in Example 1. The treatment method includes the following steps:

[0086] Sewage with an initial sludge concentration of 7 g / L is introduced into the reaction tank 3 from the water inlet. Under the power supply state, the sewage is filtered through the cathode of the membrane module until the water quality of the effluent meets the standard and then discharged.

[0087] The filtration treatment includes a cyclic first power supply state and a second power supply state;

[0088] The voltage of the first power supply state is 0.2V, and the time is 59min;

[0089] The voltage of the second power supply state is 12V, and the time is 1min;

[0090] The discharge includes a cyclic discharge state and a stop state;

[0091] The time of the discharge state is 6min;

[0092] The flux of the discharge state is 30LMH;

[0093] The time of the stop state is 4min.

[0094] Application Example 3

[0095] This application example provides a sewage treatment method, using the membrane electrode sewage treatment device with in-situ cleaning function provided in Example 1. The treatment method includes the following steps:

[0096] Sewage with an initial sludge concentration of 7g / L is introduced into the reaction tank 3 from the water inlet. Under the power supply state, the sewage is filtered through the cathode of the membrane module until the effluent quality meets the standard and then discharged;

[0097] The filtration treatment includes a cyclic first power supply state and a second power supply state;

[0098] The voltage of the first power supply state is 0.6V, and the time is 57min;

[0099] The voltage of the second power supply state is 8V, and the time is 3min;

[0100] The discharge includes a cyclic discharge state and a stop state;

[0101] The time of the discharge state is 6min;

[0102] The flux of the discharge state is 45LMH;

[0103] The time of the stop state is 4min.

[0104] Application Example 4

[0105] The difference between this application example and Application Example 1 is only that, except that the voltage of the second power supply state is 7.5V, the rest are the same as Application Example 1.

[0106] Application Example 5

[0107] The difference between this application example and Application Example 1 is only that, except that the voltage of the second power supply state is 12.5V, the rest are the same as Application Example 1.

[0108] Application Example 6

[0109] The difference between this application example and Application Example 1 is only that, except that the time of the second power supply state is 0.5 min, the rest are the same as Application Example 1.

[0110] Application Example 7

[0111] The difference between this application example and Application Example 1 is only that, except that the voltage of the second power supply state is 3.5 min, the rest are the same as Application Example 1.

[0112] Application Example 8

[0113] The difference between this application example and Application Example 1 is only that, except that the membrane electrode sewage treatment device with in-situ cleaning function provided in Example 2 is adopted, the rest are the same as Application Example 1.

[0114] Application Example 9

[0115] The difference between this application example and Application Example 1 is only that, except that the membrane electrode sewage treatment device with in-situ cleaning function provided in Example 3 is adopted, the rest are the same as Application Example 1.

[0116] Application Example 10

[0117] The difference between this application example and Application Example 1 is only that, except that the membrane electrode sewage treatment device with in-situ cleaning function provided in Example 4 is adopted, the rest are the same as Application Example 1.

[0118] Application Example 11

[0119] The difference between this application example and Application Example 1 is only that, except that the filtration treatment only includes the first power supply state, the rest are the same as Application Example 1.

[0120] Application Example 12

[0121] The difference between this application example and Application Example 1 is only that, except that the filtration treatment only includes the second power supply state, the rest are the same as Application Example 1.

[0122] Comparative Application Example 1

[0123] The difference between this comparative application example and Application Example 1 is only that, except that the membrane electrode sewage treatment device with in-situ cleaning function provided in Comparative Example 1 is adopted, the rest are the same as Application Example 1.

[0124] Testing Method

[0125] Collect the transmembrane pressure difference of the TMP recorder in Application Examples 1 - 12 and Comparative Application Example 1, test the water quality of the effluent to record the concentration of suspended solids, record the membrane fouling cycle, and record the data in Table 1.

[0126] Table 1

[0127] Transmembrane pressure difference / kPa Concentration of solid suspended matter / mg / L Membrane fouling cycle / days Application Example 1 38 7000 18 Application Example 2 38 7000 23 Application Example 3 45 6500 20 Application Example 4 40 7000 17 Application Example 5 42 8000 10 Application Example 6 49 4500 15 Application Example 7 48 7000 15 Application Example 8 40 6500 17 Application Example 9 43 6000 15 Application Example 10 49 7500 12 Application Example 11 45 6500 9 Application Example 12 49 7000 9 Comparative Application Example 1 69 7000 6

[0128] It can be seen from the test results that:

[0129] (1) It can be seen from Application Examples 1 - 12 and Comparative Application Example 1 that by introducing the electro - cleaning technology, the present invention realizes in - situ cleaning of the cathode of the membrane module, effectively removes the pollutants accumulated on the membrane surface, reduces the influence of membrane fouling on the membrane flux, thereby prolongs the service life of the membrane module, and improves the operation stability of the system; by improving the coupling mode between the electrode and the membrane module and the electric - field distribution, the uniformity of the cleaning effect is enhanced, and the by - products that may be generated during the electrochemical reaction are reduced, ensuring the high efficiency and environmental protection of the cleaning process.

[0130] (2) It can be seen from Application Example 1 and Application Examples 4 - 7 that by further regulating the voltage and time of the second power - supply state, the present invention can further improve the service life of the membrane electrode and also improve the cleaning effect.

[0131] (3) It can be seen from Application Example 1 and Application Example 8 that when the present invention uses two anode electrodes, a uniformly distributed electric field can be obtained, thereby improving the cleaning effect and further improving the service life of the membrane electrode.

[0132] (4) It can be seen from Application Example 1 and Application Examples 9 - 10 that by using a graphite anode, the present invention can reduce the device cost while also reducing the electro - flocculation reaction in the device, thereby improving the service life of the membrane electrode.

[0133] (5) It can be seen from Application Example 1 and Application Examples 11 - 12 that by cycling between the first power - supply state and the second power - supply state, the present invention improves the service life of the membrane electrode.

[0134] In summary, by introducing the electro - cleaning technology, the present invention realizes in - situ cleaning of the membrane module, effectively removes the pollutants accumulated on the membrane surface, reduces the influence of membrane fouling on the membrane flux, thereby prolongs the service life of the membrane module, and improves the operation stability of the system; by improving the coupling mode between the electrode and the membrane module and the electric - field distribution, the uniformity of the cleaning effect is enhanced, and the by - products that may be generated during the electrochemical reaction are reduced, ensuring the high efficiency and environmental protection of the cleaning process.

[0135] The applicant declares that the above - mentioned is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A membrane electrode sewage treatment device with an in-situ cleaning function, characterized in that, The membrane electrode sewage treatment device includes a reaction tank, and an anode and a membrane module cathode are arranged in the reaction tank; The membrane electrode sewage treatment device further includes a power supply device, the positive electrode of the power supply device is electrically connected to the anode, and the negative electrode of the power supply device is electrically connected to the membrane module cathode; A water outlet is arranged at the top of the shell of the reaction tank, and the water outlet is communicated with the membrane module cathode through a membrane module outlet.

2. The membrane electrode sewage treatment device according to claim 1, wherein The anode is graphite or carbon felt; Preferably, the number of the anodes ≥ 1.

3. The membrane electrode sewage treatment device according to claim 1 or 2, characterized in that, The membrane module used for the membrane module cathode is a conductive membrane; Preferably, the conductive membrane is a microfiltration membrane, an ultrafiltration membrane or a nanofiltration membrane; Preferably, the material of the conductive membrane is stainless steel or titanium metal; Preferably, the filtration accuracy of the membrane module is 0.2μm - 0.25μm; Preferably, the number of the membrane module cathodes ≥ 1.

4. The membrane electrode sewage treatment device according to any one of claims 1-3, characterized in that, A water inlet is arranged at the bottom of the shell of the reaction tank; Preferably, a taper joint is welded to the membrane module outlet, and the taper joint is connected to the water outlet pipe of the water outlet; Preferably, an external device is arranged on the pipeline of the water outlet pipe, and the external device includes an external TMP recorder and an external water outlet pump.

5. The membrane electrode sewage treatment device according to claim 4, characterized in that, The external water outlet pump is connected to a time relay; Preferably, the external water outlet pump is a basic type peristaltic pump.

6. The membrane electrode sewage treatment device according to any one of claims 1-5, characterized in that, The power supply device is a DC power supply.

7. A sewage treatment method, characterized in that, The sewage treatment method uses the membrane electrode sewage treatment device according to any one of claims 1 - 6, and includes the following steps: Sewage is introduced into the reaction tank, and under the power supply state, the sewage is filtered through the membrane module cathode until the water quality of the effluent reaches the standard and then is discharged.

8. The sewage treatment method according to claim 7, characterized in that, The filtration treatment includes a first power supply state and a second power supply state that cycle; Preferably, the voltage of the first power supply state is 0.2V - 0.6V, and the time is 57min - 59min; Preferably, the voltage of the second power supply state is 8V - 12V, and the time is 1min - 3min.

9. The sewage treatment method according to claim 8, characterized in that, The transmembrane pressure difference of the second power supply state is 35kPa - 40kPa.

10. The sewage treatment method according to any one of claims 7-9, characterized in that The discharge includes a discharge state and a stop state that cycle; Preferably, the flow rate of the discharge state is 30LMH - 50LMH, and the time is 6min - 8min; Preferably, the time of the stop state is 2min - 4min.

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