MABR-MBfR combined sewage treatment system and method

Abstract

According to the MABR-MBfR combined sewage treatment system and method provided by the invention, main pollutants such as organic matters, nitrogen and the like in sewage and refractory substances in the sewage are effectively removed by utilizing the high-efficiency synchronous nitrification and denitrification and organic matter removal capability of the MABR and the deep denitrification and refractory substance removal performance of the MBfR, an external carbon source is not needed, the operation is simple, and the cost is low. And moreover, stable operation and low-energy-consumption operation of the system can be realized, and the overall effect of sewage treatment is remarkably improved. In addition, air supply sources of the MABR and the MBfR can be prepared by electrolyzing water through direct-current electric energy converted by a solar photovoltaic system, or air is directly input, so that the operation cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and relates to a MABR-MBfR combined sewage treatment system and method. Background Art

[0002] With the rapid development of industrialization and urbanization, the amount of sewage discharge has continued to increase, causing serious pollution to the environment and posing a threat to human health. The continuous improvement of the country's sewage treatment standards has made sewage treatment plants more stringent in terms of discharge indicators such as total nitrogen, chemical oxygen demand (COD), and total phosphorus in effluent. Although traditional sewage treatment methods, such as activated sludge method, oxidation ditch method, and biological filter, can remove organic pollutants and some nitrogen and phosphorus nutrients in sewage to a certain extent, they still have many shortcomings in terms of treatment efficiency, treatment cost, and energy consumption.

[0003] MABR (Membrane Aerated Biofilm Reactor) and H2-MBfR (Hydrogen based-Membrane Biofilm Reactor) are both advanced wastewater treatment technologies that use a combination of membranes and biofilms. Compared with other membrane technologies, the permeable membrane used in MABR is not used as a filter for wastewater, but is used to transport the gas required for wastewater treatment, with a transfer efficiency of up to 100%. In MABR, oxygen is transferred to the inside of the biofilm through the membrane surface, and pollutants enter the inside of the biofilm from the liquid phase in the other direction. The transfer of electron donors and electron acceptors is reversed. This mass transfer method enables MABR to use oxygen more efficiently. At the same time, by controlling the aeration pressure, a unique biofilm layered structure is formed on the membrane surface, which is divided into an aerobic layer, an anoxic layer, and an anaerobic layer in turn. MABR can achieve BOD (Biochemical oxygen demand) removal, nitrification, and denitrification in a single biofilm, thereby improving the activity of microorganisms inside the biofilm and the wastewater treatment efficiency. H2-MBfR achieves nitrate nitrogen (NO3 - -N) and autotrophic reduction of difficult-to-degrade pollutants. This process does not require an external carbon source, avoiding secondary pollution of the effluent and increased costs caused by the addition of an external carbon source for anaerobic denitrification in the AAO process. It is suitable for deep treatment of substandard secondary effluent and industrial wastewater.

[0004] Although MABR and MBfR each show unique advantages in sewage treatment, a single technology still has some limitations in practical application. For example, the invention patent with the authorization announcement number CN109650541B discloses a sewage treatment method based on multi-stage A / O and MABR. Although this method can treat decentralized domestic sewage, it has certain difficulties in treating high-concentration organic pollutants and difficult-to-degrade substances, and the aerobic zone still uses traditional aeration methods, which causes a lot of energy consumption. Another example is the invention patent with the authorization announcement number CN114790037B, which discloses a hydrogen matrix biofilm reactor combined device for controlling the amount of CO2 added and a method for treating nitrate-containing sewage. This method uses the CO2 accurately added by the CO2 supply system as an inorganic carbon source for hydrogen autotrophic microorganisms and controls the pH of the system, so that H2-MBfR maintains long-term, efficient and stable operation during the denitrification process, but it is only suitable for the treatment of nitrate-containing sewage. At present, there is no process implementation that directly couples MABR and MBfR for sewage treatment. Summary of the invention

[0005] Based on the above technical problems to be solved, the object of the present invention is to provide a MABR-MBfR combined sewage treatment system and method.

[0006] To achieve the above object, the present invention adopts the following technical solutions: The present invention provides a MABR-MBfR combined sewage treatment system, comprising an air supply device and an anoxic MABR pool, an aerobic MABR pool and an MBfR pool connected in series, wherein the air supply device introduces air or oxygen into the anoxic MABR pool and the aerobic MABR pool, and the air supply device introduces hydrogen into the MBfR pool; at least one membrane module device is arranged in each of the anoxic MABR pool, the aerobic MABR pool and the MBfR pool, and the gas outlet of the air supply device is located inside the membrane module.

[0007] Preferably, a set of the membrane assembly device is composed of at least one membrane assembly unit, and the number of membrane assemblies is adjusted according to the tank capacity.

[0008] Preferably, the membrane assembly unit is one of a plate membrane assembly, a curtain membrane assembly and a roll membrane assembly.

[0009] Preferably, the plate-type membrane assembly comprises a microporous breathable membrane and a support frame arranged outside the microporous breathable membrane.

[0010] Preferably, the microporous breathable membrane is selected from one of a polytetrafluoroethylene membrane, a polyvinylidene fluoride membrane, a polyethersulfone membrane and a polyamide membrane.

[0011] Preferably, the pore size of the microporous breathable membrane is 0.1 μm-3.0 μm.

[0012] Preferably, the system further comprises: a coarse screen, a lift pump room, a fine screen, a sand settling tank and an adjusting tank which are connected in sequence, and the adjusting tank is connected to the anoxic MABR tank; the MBfR tank is also connected to a secondary sedimentation tank and a sludge thickening tank in sequence, and the secondary sedimentation tank is respectively connected to a flocculation reaction tank and anoxic MABR tank, and the flocculation reaction tank is also connected to an ultraviolet disinfection tank.

[0013] The present invention also provides a MABR-MBfR combined sewage treatment method, comprising: The raw sewage is filtered and treated with sand settling before entering the anoxic MABR tank, so that the anoxic MABR tank removes most of the COD and part of the ammonia nitrogen to obtain anoxic treated sewage; The anoxic treated sewage enters the aerobic MABR tank, so that the aerobic MABR tank removes the remaining ammonia nitrogen through microbubble aeration to obtain aerobic treated sewage; The aerobic treated sewage enters the MBfR pool, so that the MBfR pool removes nitrate nitrogen and difficult-to-degrade substances through bubble-free hydrogen aeration to obtain repaired sewage.

[0014] Preferably, the gas supply pressures in the anoxic MABR tank, the aerobic MABR tank and the MBfR tank are 1-40 kPa, 1-40 kPa and 1-25 kPa, respectively.

[0015] Preferably, the hydraulic retention time in the anoxic MABR tank, the aerobic MABR tank and the MBfR tank is 1-10h, 2-15h and 2-15h respectively.

[0016] The present invention has the following beneficial effects: (1) In the present application, the setting of the membrane assembly device can improve the gas transfer efficiency and the gas utilization efficiency; at the same time, it can also quickly form a biofilm on the outer surface of the microporous breathable membrane in the membrane assembly device. Compared with the hollow fiber membrane structure, since the flat plate area of ​​the support frame is larger, the formed biofilm can be firmly formed on the outside of the breathable membrane and is not easy to fall off. It has high activity, large thickness, and good mass transfer effect. At the same time, it improves the removal flux and solves the existing problems of slow biofilm formation, easy to fall off, and easy membrane pollution.

[0017] (2) This application adopts the combined technology of MABR and MBfR. Nitrification reaction occurs in the anoxic MABR pool, removing part of the ammonia nitrogen and producing a large amount of nitrate nitrogen. At the same time, heterotrophic bacteria in the anoxic state use the organic matter in the influent as an electron donor to reduce the nitrate nitrogen, realizing simultaneous nitrification and denitrification. The organic matter in the sewage is used by aerobic bacteria or heterotrophic bacteria to achieve COD removal. The aerobic MABR pool can undergo nitrification with the sewage to remove the remaining ammonia nitrogen in the sewage. The MBfR pool removes the nitrate nitrogen produced in the anoxic MABR pool and the difficult-to-degrade substances in the sewage by enriching hydrogen autotrophic denitrifying bacteria. There is no need to add an external carbon source or increase the reflux of digestate between pools, thereby reducing treatment costs.

[0018] (3) Anoxic MABR tanks and MBfR tanks are bubble-free aeration environments, while aerobic MABR tanks are microbubble aeration environments. Bubble-free aeration and microbubble aeration can improve gas utilization efficiency, avoid large amounts of gas waste caused by traditional aeration methods, and save operating costs.

[0019] (4) The oxygen and hydrogen used in this application are produced by electrolysis of water, and the electricity used can be obtained by relying on a solar photovoltaic panel power generation device. The application is suitable for upgrading existing sewage treatment plants to achieve low-carbon or carbon-free sewage treatment, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the structure of a MABR-MBfR combined sewage treatment system provided in an embodiment of the present application; Figure 2 Schematic diagram of the removal rates of different pollutants in the anoxic MABR tank under air and pure oxygen in Example 1 of the present application; Figure 3 This is a schematic diagram of the removal efficiency of nitrate nitrogen in the MBfR pool in Example 1 of the present application; Figure 4 This is a detection diagram of nitric nitrogen removal rate and removal flux of the long-term operation of the control group MBfR reactor provided in the examples of the present application; Figure 5 This is a detection diagram of nitric nitrogen removal rate and removal flux of the long-term operation of the MBfR reactor of the experimental group provided in the examples of the present application. DETAILED DESCRIPTION

[0021] In this application, the efficient simultaneous nitrification and denitrification and organic matter removal capabilities of MABR and the deep denitrification and difficult-to-degrade substance removal performance of MBfR are utilized to effectively remove major pollutants such as organic matter, nitrogen and phosphorus in sewage, and to achieve stable operation and low energy consumption of the system, significantly improving the overall effect of sewage treatment.

[0022] Specifically, the present invention provides a MABR-MBfR combined sewage treatment system, which includes an air supply device and an anoxic MABR tank, an aerobic MABR tank and an MBfR tank connected in series, as shown in the attached Figure 1 shown.

[0023] Among them, the gas supply device introduces air or oxygen into the anoxic MABR pool and the aerobic MABR pool, and the gas supply pressure is 1-40kPa and 1-40kPa respectively, so that bubble-free aeration and micro-bubble aeration are achieved inside the anoxic MABR pool and the aerobic MABR pool, respectively. Preferably, the gas supply pressures of the gas supply device to the anoxic MABR pool and the aerobic MABR pool are 18kPa and 30kPa, respectively. The gas supply device introduces hydrogen into the MBfR pool, and the gas supply pressure is 1-25kPa, so that bubble-free aeration is achieved inside the MBfR pool. Preferably, the gas supply pressure of the gas supply device to the MBfR pool is 15 kPa.

[0024] In the embodiments of the present application, the oxygen and hydrogen used are produced by electrolysis of water, and the electric energy used can be obtained by a solar photovoltaic panel power generation device.

[0025] In addition, the air supply device in the embodiment of the present application is a complete process device integrating hardware and software, which controls aeration based on online inlet water volume and inlet water quality, and adopts zone control to maintain stable aeration in each zone, thereby greatly reducing aeration energy consumption.

[0026] At least one membrane module device is provided in each of the anoxic MABR pool, the aerobic MABR pool and the MBfR pool, and the membrane module devices are vertically placed in the anoxic MABR pool, the aerobic MABR pool and the MBfR pool. The number of membrane module devices in the anoxic MABR pool, the aerobic MABR pool and the MBfR pool can be specifically adjusted according to the pool capacity.

[0027] In the embodiment of the present application, a set of membrane assembly devices is formed by combining at least one membrane assembly, wherein the number of the membrane assemblies is adjusted according to the size of the tank capacity. Preferably, a set of membrane assembly devices includes 5 membrane assemblies. The membrane assembly in the embodiment of the present application is one of a plate membrane assembly, a curtain membrane assembly and a roll membrane assembly.

[0028] Specifically, the plate-type membrane assembly includes a microporous breathable membrane and a support frame arranged outside the microporous breathable membrane. The gas outlet of the gas supply device is located at the microporous breathable membrane to allow gas to diffuse outward from the inside of the plate-type membrane assembly.

[0029] The microporous breathable membrane is a film made of a polymer chemical material, which can efficiently remove ammonia nitrogen from wastewater when used in sewage treatment. In the embodiment of the present application, the microporous breathable membrane is selected from a polytetrafluoroethylene membrane, a polyvinylidene fluoride membrane, a polyethersulfone membrane and a polyamide membrane, and its pore size is 0.1μm-3.0μm, and the microporous breathable membrane is formed into a whole by hot-melt pressing two by two. Preferably, the pore size of the microporous breathable membrane is 0.45μm. The aspect ratio of the microporous breathable membrane in the embodiment of the present application is 23:17, and the size can be specifically adjusted according to the size of the pool capacity.

[0030] The support frame is used to fix the microporous breathable membrane. Since the microporous breathable membrane has a large specific surface area, the formed biofilm can be firmly attached to the outside of the breathable membrane and is not easy to fall off. It has high activity, large thickness, good mass transfer effect, and improves the removal flux.

[0031] The curtain membrane module includes a membrane wire composed of a plurality of hollow fiber membranes and a membrane frame for fixing and supporting the membrane wire. The gas outlet of the gas supply device is connected to the interface on one side of the membrane wire, so that the gas diffuses from the inside of the hollow fiber membrane to the outside.

[0032] The roll-type membrane module is formed by rolling two bonded flat membranes, specifically including a flat membrane sheet and a spacer grid layer between the membrane sheets. The gas outlet of the gas supply device is connected to the inside of the flat membrane, so that the gas diffuses outward through the flat membrane.

[0033] The embodiment of the present application also includes a liquid drive device, and the anoxic MABR pool, the aerobic MABR pool and the MBfR pool are all equipped with a liquid drive device. The liquid drive device generates centrifugal force or positive pressure by driving the impeller or gear to rotate through a motor, sucking the liquid from the inlet of the liquid drive device, and pushing it to the outlet through pressure, so as to achieve uniform mixing of sludge and sewage inside the anoxic MABR pool, the aerobic MABR pool and the MBfR pool, and realize internal circulation at the same time, thereby ensuring sufficient mass transfer in the pool. The setting of the liquid drive device can improve the mass transfer effect between microorganisms and pollutants in sewage, and meet the hydraulic disturbance of each reaction zone. In the embodiment of the present application, the liquid drive device includes a circulation pump.

[0034] In addition, the sewage treatment system provided in the embodiment of the present application also includes a coarse screen, a lifting pump room, a fine screen, a sand settling tank and a regulating tank which are connected in sequence, and the regulating tank is connected to the anoxic MABR tank. The MBfR tank is also connected to the secondary sedimentation tank and the sludge concentration tank in sequence, and the secondary sedimentation tank is respectively connected to the flocculation reaction tank and the anoxic MABR tank, and the flocculation reaction tank is also connected to the ultraviolet disinfection tank.

[0035] The raw sewage is treated by the coarse screen, lift pump room, fine screen, sand settling tank and regulating tank before entering the anoxic MABR tank. After being treated by the anoxic MABR tank, aerobic MABR tank and MBfR tank, it enters the secondary sedimentation tank, sludge concentration tank, flocculation reaction tank and ultraviolet disinfection tank for reprocessing. Among them, the sewage generated in the secondary sedimentation tank is re-entered into the anoxic MABR tank for reprocessing by external return.

[0036] In addition, the present application also provides a MABR-MBfR combined sewage treatment method, the method comprising: S01: The raw sewage enters the anoxic MABR tank after filtration and sand settling treatment, so that the anoxic MABR tank removes most of the COD and part of the ammonia nitrogen to obtain anoxic treated sewage.

[0037] The raw sewage generated by urban life passes through the coarse screen, lift pump room, and fine screen to filter out large solid wastes and then enters the grit tank for grit treatment. The raw sewage after grit treatment is adjusted to a suitable pH through the regulating tank and then enters the anoxic MABR tank.

[0038] In the anoxic MABR pool, the gas supply device introduces air or oxygen with a gas supply pressure of 1-40kPa into the anoxic MABR pool. The air or oxygen is transported to the microporous breathable membrane inside the membrane assembly at a gas supply pressure lower than the bubble point pressure, and then diffuses from the inside to the outside in the membrane assembly. At this time, according to the diffusion direction of the gas, the surface of the breathable membrane forms a layered biofilm of an aerobic layer, an anoxic layer and an anaerobic layer from the inside to the outside. In the layered biofilm, air diffuses into the biofilm attached to the surface of the breathable membrane in the form of microscopic molecules, and fully transfers mass under the action of the circulating water flow to achieve bubble-free aeration. In the aerobic layer, nitrifying bacteria are in a high dissolved oxygen environment, nitrification reaction occurs, part of the ammonia nitrogen is removed, and a large amount of nitrate nitrogen is produced. At the same time, the heterotrophic bacteria in the anoxic state in the anoxic layer use the organic matter in the influent as an electron donor to reduce nitrate nitrogen, realizing simultaneous nitrification and denitrification. In addition, the organic matter in the sewage is used by aerobic bacteria or heterotrophic bacteria to remove COD and obtain anoxic treated sewage.

[0039] In the embodiment of the present application, the hydraulic retention time of the raw sewage in the anoxic MABR pool is 1-10 hours. Preferably, when pure oxygen is introduced into the anoxic MABR pool, the hydraulic retention time of the raw sewage in the anoxic MABR pool is 6 hours; when air is introduced into the anoxic MABR pool, the hydraulic retention time of the raw sewage in the anoxic MABR pool is 7.5 hours. After treatment in the anoxic MABR pool, more than 90% of COD removal and 50% to 60% of ammonia nitrogen removal are achieved through anaerobic digestion and simultaneous nitrification and denitrification reactions.

[0040] S02: The anoxic treated sewage enters the aerobic MABR tank, so that the aerobic MABR tank removes the remaining ammonia nitrogen through microbubble aeration to obtain aerobic treated sewage.

[0041] The anoxic treated sewage obtained by the anoxic MABR pool treatment enters the aerobic MABR pool for aerobic nitrification reaction. In the aerobic MABR pool, the air supply device introduces air with a supply pressure of 1-40kPa into the anoxic MABR pool. The air is transported to the microporous breathable membrane inside the membrane assembly at a supply pressure slightly higher than the bubble point pressure, and then diffuses from the inside to the outside in the membrane assembly. At this time, a biofilm mainly composed of an aerobic layer is formed on the surface of the breathable membrane. In the aerobic biofilm, air diffuses into the biofilm attached to the surface of the breathable membrane in the form of gas, and fully transfers mass under the action of the circulating water flow to achieve microbubble aeration. Under the action of aerobic bacteria in the aerobic biofilm, nitrification occurs with the sewage to remove the remaining ammonia nitrogen in the sewage and obtain aerobic treated sewage.

[0042] In the embodiment of the present application, the hydraulic retention time of the anoxic treated sewage in the aerobic MABR tank is 2-15 hours, and preferably, the hydraulic retention time is 6 hours.

[0043] S03: The aerobic treated sewage enters the MBfR pool, so that the MBfR pool removes nitrate nitrogen and difficult-to-degrade substances through bubble-free hydrogen aeration to obtain repaired sewage.

[0044] The aerobic treated sewage obtained by aerobic MABR pool treatment enters the MBfR pool for denitrification reaction. Specifically, in the MBfR pool, the gas supply device introduces hydrogen with a gas supply pressure of 1-25kPa into the MBfR pool. Hydrogen is transported to the microporous breathable membrane inside the membrane assembly at a gas supply pressure lower than the bubble point pressure, and then diffuses from the inside to the outside in the plate-type composite membrane assembly. At this time, the surface of the breathable membrane is mainly enriched with hydrogen autotrophic denitrifying bacteria to form a biofilm structure with denitrification function. In this structure, hydrogen diffuses into the biofilm attached to the surface of the breathable membrane in the form of microscopic molecules, and fully transfers mass under the action of the circulating water flow to achieve bubble-free aeration. In the biofilm with denitrification function, the nitrate nitrogen produced in the anoxic MABR pool and the difficult-to-degrade substances in the sewage are removed by enriching hydrogen autotrophic denitrifying bacteria to form repaired sewage. This process does not require an external carbon source or increase the reflux of digested liquid between pools.

[0045] In the embodiment of the present application, the hydraulic retention time of the aerobic treated sewage in the MBfR pool is 2-15 hours, and preferably, the hydraulic retention time is 2 hours. After treatment in the MBfR pool, nearly 100% of the nitrate nitrogen is deeply removed, ensuring that the total nitrogen concentration reaches the Class A standard of the Municipal Wastewater Discharge Standard (GB18918-2002).

[0046] The technical solution of the present invention is further explained and illustrated by means of specific embodiments below.

[0047] Example 1 Simulated domestic sewage was prepared, wherein the water quality of the simulated domestic sewage was 300 mg / L COD, 150 mg / L BOD, 50 mg / L TN, and 40 mg / L NH3-N. The prepared simulated domestic sewage was sequentially passed through the anoxic MABR pool, aerobic MABR pool, and MBfR pool for reaction treatment, and the hydraulic retention time was 7.5h, 6h, and 2h, respectively. The anoxic MABR pool was respectively passed through pure oxygen and air for testing, and the concentrations of different pollutants at the effluent of the anoxic MABR pool and MBfR pool were measured to evaluate the removal capacity of the sewage treatment system and obtain the attached Figure 2 , 3 .

[0048] By the attached Figure 2 It can be seen that COD degradation and simultaneous nitrification and denitrification of part of the ammonia nitrogen occurred in the anoxic MABR pool. Under the condition of pure oxygen, the COD removal rate reached 87.2% after 6 hours, and the ammonia nitrogen degradation rate reached 56.7%; after 7.5 hours, the COD removal rate reached 89.9%, and the ammonia nitrogen degradation rate reached 88.2%. Under the condition of air, the COD removal rate reached 84.1% after 6 hours, and the ammonia nitrogen degradation rate reached 38.9%; after 7.5 hours, the COD removal rate reached 88.3%, and the ammonia nitrogen degradation rate reached 52.9%. It can be seen that COD removal and ammonia nitrogen degradation can be achieved under the conditions of air and pure oxygen, and the removal effect is better under pure oxygen conditions. By the attached Figure 3 It can be seen that hydrogen autotrophic denitrification mainly occurs in the MBfR pool, and 20 mg / L of nitrate nitrogen can be completely removed within 2 hours, achieving effluent water quality standards.

[0049] Example 2 In order to verify that the membrane assembly provided by the embodiment of the present invention has the advantages of preventing microporous breathable membrane pollution and improving the pollutant removal flux, two groups of hydrogen-type MBfR reactors were set up and operated for two months. The control group used a commercially available polytetrafluoroethylene microporous breathable membrane without any treatment, and the experimental group used the membrane assembly provided by the embodiment of the present invention, and the microporous breathable membrane used in the membrane assembly was a polytetrafluoroethylene microporous breathable membrane with support frames on both sides. The influent nitrate nitrogen concentration of the two groups of hydrogen-type MBfR reactors was set to 20 mg / L, and the removal capacity of the two groups of hydrogen-type MBfR reactors under different operating disturbances such as hydraulic retention time, temperature and influent load was investigated, and the attached Figure 4 , 5 Among them, Figure 4 , 5Days 0-14 are the test results under different hydraulic retention times, days 15-25 are the test results under low temperature disturbance, days 26-32 are the test results under low temperature disturbance recovery stage, days 33-53 are the test results under high load disturbance, and days 54-60 are the test results under high load disturbance recovery stage.

[0050] By the attached Figure 4 It can be seen that the control group had a certain ability to remove nitrate nitrogen within 5 days of operation; the ability to remove nitrate nitrogen seriously decreased on the 6th to 10th day of operation; when it was running for 10th to 14th day, it could no longer remove nitrate nitrogen. When low temperature disturbance and high load disturbance occurred during operation, the control group was also unable to remove nitrate nitrogen. This shows that the control group had membrane fouling after one week of operation, and the nitrate nitrogen removal rate, removal flux and total nitrogen removal rate were reduced to nearly 0 regardless of the disturbance conditions.

[0051] By the attached Figure 5 It can be seen that under different hydraulic retention time disturbances from day 0 to day 14, the removal rate of nitrate nitrogen in the experimental group was close to 100%, and the removal flux was between 12.5 and 18 g / m 2 / d; under low temperature disturbance on the 15th to 25th day, the removal rate of nitrate nitrogen was 60-92%, and the removal flux was 12.5-20 g / m 2 / d; under high load disturbance on the 33rd to 53rd day, the removal rate of nitrate nitrogen was 40-98%, and the removal flux was 10-28.4 g / m 2 / d. This shows that the experimental group can still remove nitrate nitrogen under different operating disturbances, and the removal flux is 16.1-23.5 g / m 2 / d, the removal rate is close to 100%, and the maximum removal flux can reach 28.4 g / m 2 / d. At the same time, the processing capacity of the experimental group was able to recover quickly after the disturbance was eliminated.

[0052] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A MABR-MBfR combined sewage treatment system, characterized in that: It comprises an air supply device and an anoxic MABR pool, an aerobic MABR pool and an MBfR pool connected in series, wherein the air supply device introduces air or oxygen into the anoxic MABR pool and the aerobic MABR pool, and the air supply device introduces hydrogen into the MBfR pool; at least one membrane module device is arranged in each of the anoxic MABR pool, the aerobic MABR pool and the MBfR pool, and the gas outlet of the air supply device is located inside the membrane module.

2. The MABR-MBfR combined sewage treatment system according to claim 1, characterized in that: A set of the membrane assembly device is composed of at least one membrane assembly unit, and the number of membrane assembly devices is adjusted according to the tank capacity.

3. The MABR-MBfR combined sewage treatment system according to claim 2, characterized in that: The membrane assembly unit is one of a plate membrane assembly, a curtain membrane assembly and a roll membrane assembly.

4. The MABR-MBfR combined sewage treatment system according to claim 3, characterized in that: The plate-type membrane assembly comprises a microporous breathable membrane and a support frame arranged outside the microporous breathable membrane.

5. The MABR-MBfR combined sewage treatment system according to claim 4, characterized in that: The microporous breathable membrane is selected from one of a polytetrafluoroethylene membrane, a polyvinylidene fluoride membrane, a polyethersulfone membrane and a polyamide membrane.

6. The MABR-MBfR combined sewage treatment system according to claim 4, characterized in that: The pore size of the microporous breathable membrane is 0.1 μm-3.0 μm.

7. The MABR-MBfR combined sewage treatment system according to claim 1, characterized in that: The system also includes: a coarse screen, a lift pump room, a fine screen, a sand settling tank and an adjusting tank which are connected in sequence, and the adjusting tank is connected to the anoxic MABR tank; the MBfR tank is also connected to a secondary sedimentation tank and a sludge thickening tank in sequence, and the secondary sedimentation tank is respectively connected to a flocculation reaction tank and anoxic MABR tank, and the flocculation reaction tank is also connected to an ultraviolet disinfection tank.

8. A MABR-MBfR combined sewage treatment method, characterized in that: include: The raw sewage is filtered and treated with sand settling before entering the anoxic MABR tank, so that the anoxic MABR tank removes most of the COD and part of the ammonia nitrogen to obtain anoxic treated sewage; The anoxic treated sewage enters the aerobic MABR tank, so that the aerobic MABR tank removes the remaining ammonia nitrogen through microbubble aeration to obtain aerobic treated sewage; The aerobic treated sewage enters the MBfR pool, so that the MBfR pool removes nitrate nitrogen and difficult-to-degrade substances through bubble-free hydrogen aeration to obtain repaired sewage.

9. The MABR-MBfR combined sewage treatment method according to claim 8, characterized in that: The gas supply pressures in the anoxic MABR tank, the aerobic MABR tank and the MBfR tank are 1-40 kPa, 1-40 kPa and 1-25 kPa, respectively.

10. The MABR-MBfR combined sewage treatment method according to claim 8, characterized in that: The hydraulic retention times in the anoxic MABR pool, the aerobic MABR pool and the MBfR pool are 1-10h, 2-15h and 2-15h respectively.

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