Oxygen-enriched membrane reactor and membrane bioreactor coupled sewage treatment system

Abstract

The application provides a kind of oxygen-enriched membrane reactor and membrane bioreactor coupling sewage treatment system, relating to domestic sewage technical field, including: coupling treatment pool, clear water pool, sludge storage pool, equipment room, guide wall, sewage inlet pipe, air supply fan, oxygen-enriched membrane reactor and inorganic membrane bioreactor;The upper portion of the coupling treatment pool is the equipment room, and the air supply fan and the control system are in the equipment room.The application integrates the oxygen-enriched membrane reactor and the inorganic membrane bioreactor by modularization reinforcement treatment, forms the aerobic zone, the facultative zone and the anaerobic zone in the oxygen-enriched membrane reactor due to its unique structure and high oxygen utilization efficiency, is used for the nitrification of ammonia nitrogen and the removal of most total nitrogen, forms simultaneous nitrification and denitrification reaction in the reactor, further strengthens the removal of pollutants in water in the inorganic membrane bioreactor, and realizes the separation of sludge and water, so that the effluent quality of the sewage treatment system is stable and up to standard under the condition of ensuring certain fluctuation of water quantity.

Description

Technical Field

[0001] This invention relates to the field of domestic sewage technology, and in particular to a sewage treatment system that couples an oxygen-enriched membrane reactor and a membrane bioreactor. Background Technology

[0002] In recent years, water pollution has received widespread attention from the public, leading to the research of various water treatment technologies. Denitrification has consistently been a hot topic in the wastewater treatment industry, with biological denitrification primarily employing two processes: activated sludge and biofilm processes. The typical activated sludge process involves setting up anaerobic, anoxic, and aerobic tanks, allowing wastewater to flow through these tanks sequentially. Sludge return and excess sludge discharge then remove COD, ammonia nitrogen, and total phosphorus from the wastewater. The biofilm process, on the other hand, involves installing packing material within the biological treatment tank, allowing a microbial film to attach and grow on the packing. Under external aeration, aerobic and facultative anaerobic microorganisms grow on the outer layer of the packing, while anaerobic microorganisms grow on the inner layer. This aerobic, facultative anaerobic, and anaerobic microbial community, evolving from the outside in, degrades pollutants such as ammonia nitrogen and total nitrogen through the cyclical renewal of the biofilm. Both wastewater treatment processes require aeration, with the dissolved oxygen concentration in the biological treatment tank adjusted by regulating valves on the aeration line. However, both of the above processes have disadvantages such as low oxygen utilization, high energy consumption, high sludge production, and large land area. Wastewater treatment faces the dual pressure of improving quality and efficiency and saving energy and reducing consumption. There is an urgent need for the development of new denitrification processes. It is imperative to research and develop new processes with high oxygen utilization efficiency, small land area, low sludge production, low energy consumption, and the ability to simultaneously degrade COD, remove nitrogen and phosphorus. Summary of the Invention

[0003] This invention relates to a wastewater treatment system that couples an oxygen-enriched membrane reactor and an inorganic membrane bioreactor. Through modular enhanced treatment, the oxygen-enriched membrane reactor and the inorganic membrane bioreactor are integrated to give full play to their respective advantages. In the oxygen-enriched membrane reactor, due to its unique structure and high oxygen utilization efficiency, aerobic, facultative, and anaerobic zones are formed for the nitrification of ammonia nitrogen and the removal of most of the total nitrogen. Simultaneous nitrification and denitrification reactions are formed in the reactor. In the inorganic membrane bioreactor, the removal of pollutants in the water is further enhanced, and the separation of sludge and water is achieved. Under the condition of ensuring a certain fluctuation in water volume, the effluent quality of the wastewater treatment system is stable and meets the standards.

[0004] This invention provides a wastewater treatment system coupling an oxygen-enriched membrane reactor and a membrane bioreactor, specifically comprising: a coupling treatment tank, a clear water tank, a sludge storage tank, an equipment room, a guide wall, a wastewater inlet pipe, an air blower, an oxygen-enriched membrane reactor, and an inorganic membrane bioreactor; the equipment room is located above the coupling treatment tank, containing the air blower and a control system; a clear water tank is located on one side of the coupling treatment tank, and a settling hopper is located at the lower end of the coupling treatment tank, with a residual sludge discharge pipe at the bottom of the settling hopper, the other end of which is connected to the sludge storage tank; a wastewater inlet pipe is located at the upper part of one end of the coupling treatment tank, and a guide wall is vertically fixed in the inner cavity of the coupling treatment tank on the side where the wastewater inlet pipe is located, with the upper end of the guide wall higher than the location of the wastewater inlet pipe, and the lower end of the guide wall leaving a gap with the bottom of the inner cavity of the coupling treatment tank; a system hydraulic stirring assembly is located at the bottom of the coupling treatment tank on the other side of the guide wall, and a cuboid oxygen-enriched membrane reactor is installed in the coupling treatment tank above the system hydraulic stirring assembly, with the upper part of the oxygen-enriched membrane reactor... An inorganic membrane bioreactor is set up, and a circular gas stirring assembly is fixed between the oxygen-enriched membrane reactor and the inorganic membrane bioreactor. One end of the oxygen-enriched membrane reactor is connected to the outlet of the blower through an air inlet pipe, and the other end of the oxygen-enriched membrane reactor is equipped with an oxygen-enriched membrane reactor tail gas collection pipe. The end of the tail gas collection pipe leads upward through the upper end of the coupling treatment tank, and a tail gas vent valve is installed on the tail gas collection pipe. An air inlet pipe is also connected to the outlet pipe of the blower, and the other end of the air inlet pipe is connected to the gas stirring assembly. The upper end of the inorganic membrane bioreactor, away from the guide wall, is equipped with a product water pump outlet pipe, and the end of the product water pump outlet pipe is located above the clear water tank. A water quality analyzer and an ultrasonic online cleaning device are installed on the upper part of the inorganic membrane bioreactor. An ultraviolet disinfection device is installed in the clear water tank. The upper end of the clear water tank is connected to a circulating water inlet pipe, and the other end of the circulating water inlet pipe is connected to a circulating water pump. The other end of the circulating water pump is connected to the system hydraulic stirring assembly.

[0005] Optionally, the settling hopper has a bucket-shaped structure that is wider at the top and narrower at the bottom. The inner end of the residual sludge discharge pipe is located at the lowest position of the settling hopper. The residual sludge discharge pipe is equipped with a control valve, and the residual sludge discharge pipe discharges sludge periodically.

[0006] Optionally, a corner guide wedge is provided at the bottom corner of the coupling treatment tank on one side of the sewage inlet pipe, and the upper end of the corner guide wedge has an inwardly concave arc structure.

[0007] Optionally, a guide inner plate is fixedly provided on the side of the guide wall away from the sewage inlet pipe, and the side of the guide inner plate away from the guide wall is a downwardly cut inclined surface structure.

[0008] Optionally, an oxygen-enriched membrane module inlet flow meter and an oxygen-enriched membrane module inlet pressure gauge are installed on the air inlet pipe connecting the air blower to the oxygen-enriched membrane reactor.

[0009] Optionally, the lower end of the oxygen-enriched membrane reactor is a rectangular gas distribution frame welded from a round tube. The two ends of the gas distribution frame are round tubes with closed ends. A gas distribution horizontal tube with uniform spacing is connected between the two round tubes. The upper end of the gas distribution horizontal tube is provided with gas holes with built-in one-way valves at uniform intervals. One end of the round tube is connected to the gas inlet pipe.

[0010] The upper end of the oxygen-enriched membrane reactor is perpendicular to the gas distribution pipe and has a uniformly spaced oxygen-enriched membrane substrate with an isosceles trapezoidal shape that is wider at the top and narrower at the bottom. The pores are connected to the interior of the oxygen-enriched membrane substrate. The inner and outer layers of the oxygen-enriched membrane substrate are bonded together by hot-melt bonding, and the middle layer is a supporting skeleton. The oxygen-enriched membrane material is a polymer material. The upper end of the oxygen-enriched membrane substrate is fixed in series by uniformly spaced tail gas collection pipes. The other end of the tail gas collection pipe is connected to the tail gas collection pipe of the oxygen-enriched membrane reactor. The near-membrane zone in the oxygen-enriched membrane reactor is an aerobic zone, suitable for the growth of nitrifying bacteria, the far-membrane zone is an anaerobic zone, suitable for the growth of denitrifying bacteria, and the middle layer is a facultative anaerobic zone.

[0011] Optionally, the system hydraulic mixing component has a ring-shaped structure. One end of the system hydraulic mixing component is connected to the outlet of the circulating water pump, and the other end of the system hydraulic mixing component is fixedly connected to the inner wall of the coupling treatment tank through a support connecting column. Water spray heads are distributed in a ring on the inner ring wall of the system hydraulic mixing component, and the water spray heads are distributed counterclockwise and obliquely upward.

[0012] Optionally, the inorganic membrane bioreactor is provided with vertically spaced inorganic membrane substrates at equal intervals. The inorganic membrane substrates are composed of a membrane structure that is wider at the top and narrower at the bottom and twisted by 180 degrees. V-shaped water purification guide plates are symmetrically fixed between two adjacent inorganic membrane substrates at the upper end of the inorganic membrane bioreactor. The lower ends of the two water purification guide plates are connected to the inner cavity of the inorganic membrane bioreactor at intervals. One end of the product water pump outlet pipe is fixedly connected to a collecting pipe that is perpendicular to one end of the water purification guide plate in the coupling treatment tank. A water pumping branch pipe is provided on the collecting pipe corresponding to each group of two water purification guide plates. The upper end of the water pumping branch pipe is a beveled structure that is obliquely cut towards the end.

[0013] The circulating water inlet pipe is located at one end in the coupling treatment tank, which is higher than the upper end of the purified water guide plate.

[0014] Optionally, the ultraviolet disinfection device has an internal mounting groove on the side facing the clear water pool. The upper end of the internal mounting groove has a beveled structure, and ultraviolet germicidal lamps are evenly spaced vertically in the internal mounting groove.

[0015] Optionally, at least six jet pipes are arranged in a counterclockwise direction on the inner ring wall of the gas stirring assembly. A support frame is fixedly provided on the gas stirring assembly below the jet pipes. A six-bladed pneumatic stirring impeller is rotatably connected to the upper middle part of the support frame via a rotating shaft. The jet direction of the jet pipes is consistent with the rotation direction of the pneumatic stirring impeller.

[0016] This invention provides a wastewater treatment system that couples an oxygen-enriched membrane reactor and a membrane bioreactor, which has the following beneficial effects:

[0017] 1. This invention uses a selectively permeable polymer oxygen-enriched membrane module. Its unique structure enables the porous membrane to supply oxygen without bubbles, achieving efficient oxygen utilization. On the other hand, it creates an aerobic-facultative-anaerobic environment in the reaction zone, allowing nitrification and denitrification to proceed simultaneously, resulting in a high efficiency in pollutant removal.

[0018] 2. This invention utilizes the high efficiency of inorganic membranes for sludge-water separation, retaining a high biomass in the reactor, resulting in a higher sludge concentration in the system, strong resistance to shock loads, and effective saving of floor space. The high-flux operation of the inorganic membrane is ensured by cleaning through air purging and ultrasonic online cleaning devices installed at the bottom of the inorganic membrane.

[0019] 3. This invention automatically adjusts operating parameters based on influent and effluent indicators, ensuring efficient, stable, and automated operation of the system. This meets the needs of the reaction zone, saves energy, and achieves efficient utilization of dissolved oxygen. 4. This invention integrates an oxygen-enriched membrane reactor and an inorganic membrane bioreactor through modular enhanced treatment, fully leveraging their respective advantages. The oxygen-enriched membrane reactor, due to its unique structure and high oxygen utilization efficiency, forms aerobic, facultative, and anaerobic zones for nitrification of ammonia nitrogen and removal of most total nitrogen. Simultaneous nitrification and denitrification reactions occur within the reactor. The inorganic membrane bioreactor further enhances the removal of pollutants from the water and achieves sludge-water separation. While ensuring a certain fluctuation in water volume, the effluent quality of the wastewater treatment system consistently meets standards, improving pollutant removal efficiency. Operation and maintenance are relatively simple, energy consumption is relatively low, ensuring more stable effluent quality, and the footprint is small. This fundamentally solves the problems of low oxygen utilization, large footprint, and failure to meet effluent pollutant standards in current conventional treatment equipment. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments will be briefly described below.

[0021] The accompanying drawings described below are only related to some embodiments of the invention and are not intended to limit the invention.

[0022] In the attached diagram:

[0023] Figure 1 A flow chart of a high-efficiency wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor according to the present invention is shown.

[0024] Figure 2 This diagram shows a first axial view of the coupling treatment tank and clear water tank of the present invention.

[0025] Figure 3 A second axial view of the coupling treatment tank and clear water tank of the present invention is shown;

[0026] Figure 4 A schematic diagram of the third axis view of the coupling treatment tank and clear water tank of the present invention is shown;

[0027] Figure 5 A schematic diagram of the coupling processing pool in the side plate removal state of the present invention is shown.

[0028] Figure 6 A schematic axial view of a portion of the hydraulic mixing assembly of the present invention is shown.

[0029] Figure 7 A schematic axial view of the oxygen-enriched membrane reactor portion of the present invention is shown;

[0030] Figure 8 A schematic diagram of the upper axial view of the inorganic membrane bioreactor section of the present invention is shown;

[0031] Figure 9 A schematic diagram of the lower axial view of the inorganic membrane bioreactor section of the present invention is shown;

[0032] Figure 10 A schematic diagram of the axial view of the clear water tank section of the present invention is shown.

[0033] List of reference numerals

[0034] 1. Coupling treatment tank; 101. Settling hopper; 102. Corner guide wedges;

[0035] 2. Clear pool;

[0036] 3. Sludge storage tank;

[0037] 4. Equipment room;

[0038] 5. Flow guide wall; 501. Flow guide inner plate;

[0039] 6. Sewage inlet pipe;

[0040] 7. Air supply fan;

[0041] 8. Oxygen-enriched membrane module inlet flow meter;

[0042] 9. Pressure gauge on the inlet pipe of the oxygen-enriched membrane module;

[0043] 10. Air intake pipe;

[0044] 11. Oxygen-enriched membrane reactor; 1101. Gas distribution frame; 1102. Gas distribution horizontal pipe; 1103. Oxygen-enriched membrane substrate; 1104. Tail gas collection pipe;

[0045] 12. Oxygen-enriched membrane reactor tail gas collection pipe;

[0046] 13. Exhaust gas vent valve;

[0047] 14. Circulating water inlet pipe;

[0048] 15. Circulating water pump;

[0049] 16. System hydraulic mixing components; 1601. Spray head; 1602. Support connecting column;

[0050] 17. Excess sludge discharge pipe;

[0051] 18. Inorganic membrane bioreactor; 1801. Inorganic membrane substrate; 1802. Water purification guide plate;

[0052] 19. Water quality testing instrument;

[0053] 20. Ultrasonic online cleaning device;

[0054] 21. Vacuum gauge;

[0055] 22. Water production pump;

[0056] 23. Water outlet pipe of the product water pump; 2301. Manifold; 2302. Pumping branch pipe;

[0057] 24. Ultraviolet disinfection device; 2401. Internal mounting slot; 2402. Ultraviolet germicidal lamp tube;

[0058] 25. Drainage pipe;

[0059] 26. Control system; 27. Air agitator assembly; 2701. Jet pipe; 2702. Support frame; 2703. Pneumatic agitator impeller. Detailed Implementation

[0060] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0061] Example 1: Please refer to Figures 1 to 10 :

[0062] This invention proposes a coupled wastewater treatment system of an oxygen-enriched membrane reactor and a membrane bioreactor, comprising: a coupled treatment tank 1, a clear water tank 2, a sludge storage tank 3, an equipment room 4, a guide wall 5, a wastewater inlet pipe 6, a blower 7, an oxygen-enriched membrane reactor 11, and an inorganic membrane bioreactor 18; the equipment room 4 is located above the coupled treatment tank 1, and contains the blower 7 and a control system 26; the clear water tank 2 is located on one side of the coupled treatment tank 1, and a settling hopper 101 is located at the lower end of the coupled treatment tank 1. The lowest end of the hopper 101 is equipped with a residual sludge discharge pipe 17, the other end of which is connected to the sludge storage tank 3. A sewage inlet pipe 6 is located at the upper part of one end of the coupling treatment tank 1. A guide wall 5 is vertically fixed inside the cavity of the coupling treatment tank 1 on the side where the sewage inlet pipe 6 is located. The upper end of the guide wall 5 is higher than the location of the sewage inlet pipe 6, and the lower end of the guide wall 5 is spaced from the bottom of the cavity of the coupling treatment tank 1. A system hydraulic mixing assembly is located at the bottom of the coupling treatment tank 1 on the other side of the guide wall 5. 16. A cuboid oxygen-enriched membrane reactor 11 is installed in the coupling treatment tank 1 above the system hydraulic mixing component 16. An inorganic membrane bioreactor 18 is installed above the oxygen-enriched membrane reactor 11. A circular gas mixing component 27 is fixed between the oxygen-enriched membrane reactor 11 and the inorganic membrane bioreactor 18. One end of the oxygen-enriched membrane reactor 11 is connected to the outlet of the blower 7 through an air inlet pipe 10. The other end of the oxygen-enriched membrane reactor 11 is equipped with an oxygen-enriched membrane reactor tail gas collection pipe 12. The end of the membrane reactor tail gas collection pipe 12 extends upward through the upper end of the coupling treatment tank 1, and the tail gas collection pipe 12 of the oxygen-enriched membrane reactor is equipped with a tail gas vent valve 13 to adjust the gas pressure of the oxygen-enriched membrane reactor 11 and keep the lower part of the coupling treatment tank 1 in a micro-oxygen environment; an air inlet pipe 10 is also connected to the air outlet pipe of the blower 7, and the other end of the air inlet pipe 10 is connected to the gas stirring assembly 27. By adjusting the valve opening, the pressure is adjusted to keep the dissolved oxygen concentration in the reaction zone at 0.4 mg / L; The upper end of the inorganic membrane bioreactor 18, away from the guide wall 5, is equipped with a product water pump outlet pipe 23. The end of the product water pump outlet pipe 23 is located above the clear water tank 2. A vacuum gauge 21 and a product water pump 22 are installed on the product water pump outlet pipe 23. A water quality analyzer 19 and an ultrasonic online cleaning device 20 are installed on the upper part of the inorganic membrane bioreactor 18. The water quality analyzer 19 mainly detects dissolved oxygen, ammonia nitrogen, and nitrate nitrogen. The water quality analyzer 19 uploads the water quality data to the control system 26. The control system 26 sets the initial air supply and circulating water volume according to the influent water quality. The effluent water quality is mainly detected by COD and ammonia nitrogen detectors. The effluent water quality is tested and the data is fed back to the control system 26. The control system 26 compares the set initial parameters. When the effluent indicators exceed the standards, the control system 26 will automatically adjust the operating parameters to ensure that the system can operate efficiently, stably, and automatically, and achieve the standard for effluent. The discharge not only meets the needs of the reaction zone and saves energy consumption, but also achieves efficient utilization of dissolved oxygen. The water quality analyzer 19 and the control system 26 are linked to the equipment. By adjusting the oxygenation amount, an aerobic, facultative, and anaerobic environment is formed in the coupled treatment tank 1. After the air passes through the oxygen-enriched membrane reactor 11, the oxygen concentration can reach more than 35%, and the oxygen utilization rate is close to 100%. Under the conditions of pH 7.5~8.5, temperature 20~30℃, and air supply pressure 20~30Kpa, when adjusting the dissolved oxygen content, simultaneous and optimal nitrification and denitrification reactions can be achieved, which can remove ammonia nitrogen and total nitrogen to the greatest extent. The inorganic membrane is cleaned by bottom air purging and coupled cleaning by ultrasonic online cleaning device 20 through PLC control system, which reduces fouling on the surface of the inorganic membrane, prevents the decrease in membrane flux, ensures high-flux operation of the inorganic membrane, and avoids fouling of the inorganic membrane bioreactor 18.

[0063] An ultraviolet disinfection device 24 is installed in the clear water tank 2; the upper end of the clear water tank 2 is connected to the circulating water inlet pipe 14, the other end of the circulating water inlet pipe 14 is connected to the circulating water pump 15, and the other end of the circulating water pump 15 is connected to the system hydraulic mixing component 16. The sludge concentration in the bottom reaction zone is further balanced by the circulating return pipe 14, and the circulation ratio is controlled according to the influent water quality.

[0064] Specifically, the settling hopper 101 has a bucket-shaped structure that is wider at the top and narrower at the bottom. The inner end of the residual sludge discharge pipe 17 is located at the lowest position of the settling hopper 101. The residual sludge discharge pipe 17 is equipped with a control valve. The residual sludge discharge pipe 17 discharges sludge periodically. By controlling the time interval of the residual sludge discharge pipe 17, the effective removal of phosphorus pollutants can be achieved.

[0065] Specifically, a corner guide wedge 102 is provided at the bottom corner of the coupling treatment tank 1 on one side of the sewage inlet pipe 6. The upper end of the corner guide wedge 102 is a concave arc structure, which can help the sewage to be evenly distributed after entering the tank and prevent the sediment in the sewage from accumulating and gathering at the corner.

[0066] Specifically, a guide inner plate 501 is fixedly installed on the side of the guide wall 5 away from the sewage inlet pipe 6. The side of the guide inner plate 501 away from the guide wall 5 is a downwardly cut inclined structure, which can ensure that the sewage can flow evenly towards the side where the oxygen-enriched membrane reactor 11 is located after entering the other side of the guide wall 5, which facilitates sewage treatment. Moreover, the guide inner plate 501 can also prevent dirt in the sewage from adhering to the surface while guiding the flow, thus ensuring the cleanliness of the guide inner plate 501.

[0067] Specifically, an oxygen-enriched membrane component inlet flow meter 8 and an oxygen-enriched membrane component inlet pressure gauge 9 are installed on the air inlet pipe 10 that connects the air supply fan 7 to the oxygen-enriched membrane reactor 11. By adjusting the opening of the inlet and outlet valves, the pressure is adjusted to fill the oxygen-enriched membrane with air, thereby controlling the performance of the oxygen-enriched membrane reactor 11 and making the reaction zone a micro-oxygen environment.

[0068] Specifically, the lower end of the oxygen-enriched membrane reactor 11 is a rectangular gas distribution frame 1101 welded from a round tube. The two ends of the gas distribution frame 1101 are round tubes with closed ends. A horizontally spaced gas distribution pipe 1102 is connected between the two round tubes. The upper end of the gas distribution pipe 1102 is provided with air holes with built-in one-way valves at even intervals. One end of the round tube is connected to the air inlet pipe 10, which can make the supplied air evenly distributed in the oxygen-enriched membrane reactor 11.

[0069] The upper end of the oxygen-enriched membrane reactor 11 is perpendicular to the gas distribution pipe 1102 and has uniformly spaced oxygen-enriched membrane substrates 1103. These substrates have an isosceles trapezoidal shape, wider at the top and narrower at the bottom, which increases the contact area between air and wastewater. Precise oxygen supply to the oxygen-enriched membrane substrates 1103 creates a significant concentration gradient of oxygen and organic matter in the attached biofilm, providing favorable conditions for simultaneous nitrification and denitrification within the biofilm. This efficiently removes pollutants such as COD, ammonia nitrogen, and total nitrogen from the reactor. The inner and outer layers of the oxygen-enriched membrane 1103 are bonded together by hot-melt bonding. The middle layer is a supporting skeleton. The oxygen-enriched membrane material is a polymer material. The upper end of the oxygen-enriched membrane substrate 1103 is fixed in series through evenly spaced tail gas collection pipes 1104. The other end of the tail gas collection pipes 1104 is connected to the tail gas collection pipe 12 of the oxygen-enriched membrane reactor. The near-membrane zone in the oxygen-enriched membrane reactor 11 is an aerobic zone, which is suitable for the growth of nitrifying bacteria. The far-membrane zone is an anaerobic zone, which is suitable for the growth of denitrifying bacteria. The middle layer is a facultative anaerobic zone.

[0070] Specifically, the system hydraulic mixing component 16 has a circular structure. One end of the system hydraulic mixing component 16 is connected to the outlet of the circulating water pump 15, and the other end of the system hydraulic mixing component 16 is fixedly connected to the inner wall of the coupling treatment tank 1 through the support connecting column 1602. The inner ring wall of the system hydraulic mixing component 16 has spray heads 1601 distributed in a ring. The spray heads 1601 are distributed counterclockwise and obliquely upward, which returns the sewage in the upper part of the system to the bottom. On the one hand, it has the effect of hydraulic mixing to prevent sludge from settling at the bottom; on the other hand, it mixes the sewage in the tank evenly, which greatly improves the removal efficiency of pollutants.

[0071] Specifically, the inorganic membrane bioreactor 18 is uniformly spaced with vertically arranged inorganic membrane substrates 1801. Each inorganic membrane substrate 1801 has a twisted membrane structure that is wider at the top and narrower at the bottom, with a twist of 180 degrees. The inorganic membrane flux of the inorganic membrane substrate 1801 is 180–250 L / m²·h, and the pore size is 0.1 μm. The permeate from the inorganic membrane substrate 1801 is discharged to the clear water tank 2 via the permeate pump 22. V-shaped purified water guide plates 1802 are symmetrically fixed between two adjacent inorganic membrane substrates 1801 at the upper end of the inorganic membrane bioreactor 18. The lower ends of the two purified water guide plates 1802 are connected to the inner cavity of the inorganic membrane bioreactor 18, which increases the contact area, allowing the purified water to rise while impurities such as particulate matter, microorganisms, or some heavy metals in the water are filtered out. Pollutants are difficult to rise, thus achieving the effect of water purification and separation. The water purification guide plate 1802 further ensures the production of purified water. One end of the water pump outlet pipe 23 in the coupling treatment tank 1 is fixedly connected to the collection pipe 2301, which is perpendicular to one end of the water purification guide plate 1802. The collection pipe 2301 is provided with a water pumping branch pipe 2302 between each group of two water purification guide plates 1802. The upper end of the water pumping branch pipe 2302 is a beveled structure that is cut at the end. Purified water can be extracted in the purified water area between the water purification guide plates 180 through the water pumping branch pipe 2302. The beveled structure allows the purified water to be extracted in an overflow manner, which can further avoid the extraction of impurities, thereby improving the water purification effect.

[0072] The circulating water inlet pipe 14 is located at one end in the coupling treatment tank 1, which is higher than the upper end of the water purification guide plate 1802. This ensures that the water in the coupling treatment tank 1 is mixed evenly, better removes pollutants, and prevents sludge from settling.

[0073] Specifically, the ultraviolet disinfection device 24 has an internal installation groove 2401 on one side facing the clear water tank 2. The upper end of the internal installation groove 2401 has a beveled structure. Ultraviolet germicidal lamps 2402 are vertically spaced evenly in the internal installation groove 2401. The use of ultraviolet disinfection method can eliminate the need for additional chemicals when disinfecting wastewater, thereby reducing the use of chemical agents and meeting the wastewater treatment requirements. The disinfected effluent can be discharged or reused as needed, realizing the green reuse of wastewater. Furthermore, the special structure of the internal installation groove 2401 can also prevent the ultraviolet light from spreading outside the tank, improving the safety of use.

[0074] Specifically, at least six counterclockwise distributed jet pipes 2701 are arranged in a ring on the inner ring wall of the gas stirring assembly 27. A support frame 2702 is fixedly installed on the gas stirring assembly 27 below the jet pipes 2701. A six-bladed pneumatic stirring impeller 2703 is rotatably connected to the upper middle part of the support frame 2702 via a rotating shaft. The jet direction of the jet pipes 2701 is consistent with the rotation direction of the pneumatic stirring impeller 2703, which can both perform gas scrubbing on the inorganic membrane module and increase the dissolved oxygen concentration in the upper part of the system.

[0075] The style of the coupling treatment pool 1 and clear water pool 2 in this system can be changed according to actual needs, and can be modularly designed and connected by pipes. It can also be designed as an integrated device. Whether modular or integrated, the device can be placed on the ground or buried underground according to the terrain.

[0076] Example 2 differs from Example 1 in that the dissolved oxygen concentration in the oxygen-enriched membrane reaction zone is 1.0 mg / L, the aeration pressure is 35 kPa, and the circulation ratio is 0.5.

[0077] Example 3 differs from Example 1 in that the dissolved oxygen concentration in the oxygen-enriched membrane reaction zone is 1.0 mg / L, the aeration pressure is 40 kPa, and the circulation ratio is 1.5.

[0078] Example 4 differs from Example 1 in that water is distributed at the bottom of the oxygen-enriched membrane reaction zone, and the upward flow velocity of the water is 4 m / h.

[0079] Example 5 differs from Example 1 in that water is distributed at the bottom of the oxygen-enriched membrane reaction zone, and the upward flow velocity of the water is 5 m / h.

[0080] Based on the above experimental records, the concentrations of COD and NH3-N in the effluent were recorded, with the discharge standards being COD ≤ 50 mg / L and NH3-N ≤ 5 mg / L. Detailed effluent results for each example are shown in Table 1.

[0081] Table 1. Effluent water quality results

[0082] Example COD (mg / L) NH3-N (mg / L) Example 1 30 3 Example 2 35 6 Example 3 30 5.5 Example 4 28 2.5 Example 5 25 2

[0083] Combined with Examples 1-5 and Table 1, the wastewater treatment system using the oxygen-enriched membrane reactor and membrane bioreactor coupled with the present application can meet the discharge standards. However, when the oxygen-enriched membrane inlet pressure is too high, resulting in high dissolved oxygen in the reaction zone, the ammonia nitrogen effluent does not meet the standards, and gas volume is wasted.

[0084] Combining Examples 4 and 5 with Example 1, and referring to Table 1, it can be seen that adjusting the upward flow velocity of the influent results in significantly better effluent quality than in Example 1. This indicates that controlling the upward flow velocity of the influent is beneficial to improving the removal efficiency of pollutants in wastewater.

[0085] The working principle of this embodiment is as follows: After pretreatment, the wastewater is lifted by a booster pump and enters the bottom of the coupling treatment tank 1 through the diversion zone for uniform water distribution. The blower 7 in the equipment room 4 is turned on to purge the oxygen-enriched membrane reactor 11 with air. One end of the oxygen-enriched membrane reactor 11 is equipped with an air inlet pipe 10, and the other end is equipped with an oxygen-enriched membrane reactor tail gas collection pipe 12. By adjusting the valve opening, the pressure is adjusted to maintain the dissolved oxygen concentration in the reaction zone at 0.4 mg / L. The oxygen-enriched membrane reactor tail gas collection pipe 12 is connected to the tail gas vent valve 13 to adjust the gas pressure of the oxygen-enriched membrane reactor 1 and maintain the lower part of the coupling treatment tank in a micro-oxygen environment. The circulating water inlet pipe 14 returns to the bottom of the coupling treatment tank 1 via the circulating water pump 15. The hydraulic stirring component 16 of the system is used to prevent sludge deposition. A water quality analyzer 19 is installed in the coupling treatment tank 1. The water quality data measured by the water quality analyzer 19 in the influent is uploaded to the control system 26. The control system sets the initial air supply and return flow rate according to the influent water quality.

[0086] The following points should be noted in this article:

[0087] 1. The accompanying drawings of the embodiments disclosed herein only relate to the structures involved in the embodiments disclosed herein; other structures can be referred to in a general design.

[0088] 2. Where there is no conflict, the embodiments and features described herein can be combined to obtain new embodiments. The above are merely specific implementations of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed herein should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor, comprising a coupled treatment tank (1), a clear water tank (2), a sludge storage tank (3), an equipment room (4), a flow guide wall (5), a wastewater inlet pipe (6), a blower (7), an oxygen-enriched membrane reactor (11), and an inorganic membrane bioreactor (18); characterized in that, Above the coupling treatment tank (1) is an equipment room (4), which contains a blower (7) and a control system (26). A clear water tank (2) is provided on one side of the coupling treatment tank (1). A settling hopper (101) is provided at the lower end of the coupling treatment tank (1). A residual sludge discharge pipe (17) is provided at the lowest end of the settling hopper (101). The other end of the residual sludge discharge pipe (17) is connected to a sludge storage tank (3). A sewage inlet pipe (6) is provided at the upper part of one end of the coupling treatment tank (1). A guide wall (5) is vertically fixed in the inner cavity of the coupling treatment tank (1) on the side where the sewage inlet pipe (6) is located. The upper end of the guide wall (5) is higher than the location of the sewage inlet pipe (6), and the lower end of the guide wall (5) is separated from the bottom of the inner cavity of the coupling treatment tank (1). The bottom of the coupling treatment tank (1) on the other side of the guide wall (5) is provided with a system hydraulic stirring assembly (16). A cuboid oxygen-enriched membrane reactor (11) is installed in the coupling treatment tank (1) above the system hydraulic stirring assembly (16). An inorganic membrane bioreactor (18) is set at the upper part of the oxygen-enriched membrane reactor (11). A circular gas stirring assembly (27) is fixed between the oxygen-enriched membrane reactor (11) and the inorganic membrane bioreactor (18). One end of the oxygen-enriched membrane reactor (11) is connected to the outlet of the blower (7) via an inlet pipe (10). The other end of the oxygen-enriched membrane reactor (11) is provided with an oxygen-enriched membrane reactor tail gas collection pipe (12). The end of the oxygen-enriched membrane reactor tail gas collection pipe (12) is led upward through the upper end of the coupling treatment tank (1), and a tail gas vent valve (13) is provided on the oxygen-enriched membrane reactor tail gas collection pipe (12). An inlet pipe (10) is also connected to the outlet pipe of the blower (7), and the other end of the inlet pipe (10) is connected to the gas stirring assembly (27). The inorganic membrane bioreactor The upper end of the reactor (18) away from the guide wall (5) is provided with a water pump outlet pipe (23), and the end of the water pump outlet pipe (23) is located above the clear water tank (2); a water quality detector (19) and an ultrasonic online cleaning device (20) are provided on the upper part of the inorganic membrane bioreactor (18); an ultraviolet disinfection device (24) is provided in the clear water tank (2); the upper end of the clear water tank (2) is connected to the circulating water inlet pipe (14), the other end of the circulating water inlet pipe (14) is connected to the circulating water pump (15), and the other end of the circulating water pump (15) is connected to the system hydraulic stirring assembly (16).

2. The wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor according to claim 1, characterized in that, The settling hopper (101) has a bucket-shaped structure that is wider at the top and narrower at the bottom. The inner end of the residual sludge discharge pipe (17) is located at the lowest position of the settling hopper (101). The residual sludge discharge pipe (17) is equipped with a control valve and discharges sludge periodically.

3. The wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor according to claim 1, characterized in that, The bottom corner of the coupling treatment tank (1) on one side of the sewage inlet pipe (6) is provided with a corner guide wedge (102), and the upper end of the corner guide wedge (102) is a concave arc structure.

4. The wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor according to claim 1, characterized in that, A guide inner plate (501) is fixedly provided on the side of the guide wall (5) away from the sewage inlet pipe (6). The side of the guide inner plate (501) away from the guide wall (5) is a sloping structure with a downward sloping cut.

5. The wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor according to claim 1, characterized in that, The air supply fan (7) is connected to the oxygen-enriched membrane reactor (11) via an air inlet pipe (10) equipped with an oxygen-enriched membrane component air inlet flow meter (8) and an oxygen-enriched membrane component air inlet pressure gauge (9).

6. The wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor according to claim 1, characterized in that, The lower end of the oxygen-enriched membrane reactor (11) is a rectangular gas distribution frame (1101) made of round tubes. The two ends of the gas distribution frame (1101) are round tubes with closed ends. The two round tubes are connected laterally by evenly spaced gas distribution horizontal tubes (1102). The upper end of the gas distribution horizontal tubes (1102) is evenly spaced with air holes with built-in one-way valves. One end of the round tube is connected to the air inlet pipe (10). The upper end of the oxygen-enriched membrane reactor (11) is perpendicular to the gas distribution pipe (1102) and has a uniformly spaced oxygen-enriched membrane substrate (1103). It is an isosceles trapezoidal structure that is wider at the top and narrower at the bottom. The pores are connected to the interior of the oxygen-enriched membrane substrate (1103). The inner and outer oxygen-enriched membranes of the oxygen-enriched membrane substrate (1103) are bonded together by hot melting. The middle layer is a supporting skeleton. The oxygen-enriched membrane material is a polymer material. The upper end of the oxygen-enriched membrane substrate (1103) is fixed in series through a uniformly spaced tail gas collection pipe (1104). The other end of the tail gas collection pipe (1104) is connected to the tail gas collection pipe (12) of the oxygen-enriched membrane reactor. The near-membrane zone in the oxygen-enriched membrane reactor (11) is an aerobic zone, which is suitable for the growth of nitrifying bacteria. The far-membrane zone is an anaerobic zone, which is suitable for the growth of denitrifying bacteria. The middle layer is a facultative anaerobic zone.

7. The wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor according to claim 1, characterized in that, The system hydraulic mixing component (16) has a circular structure. One end of the system hydraulic mixing component (16) is connected to the outlet of the circulating water pump (15), and the other end of the system hydraulic mixing component (16) is fixedly connected to the inner wall of the coupling treatment tank (1) through the support connecting column (1602). The inner ring wall of the system hydraulic mixing component (16) is distributed with spray heads (1601) in a ring shape, and the spray heads (1601) are distributed obliquely upward in a counterclockwise direction.

8. The wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor according to claim 1, characterized in that, The inorganic membrane bioreactor (18) is uniformly spaced with vertical inorganic membrane substrates (1801). The inorganic membrane substrates (1801) are composed of a membrane structure that is wider at the top and narrower at the bottom and twisted by 180 degrees. V-shaped water purification guide plates (1802) are symmetrically fixed between two adjacent inorganic membrane substrates (1801) at the upper end of the inorganic membrane bioreactor (18). The lower ends of the two water purification guide plates (1802) are connected to the inner cavity of the inorganic membrane bioreactor (18). One end of the water pump outlet pipe (23) in the coupling treatment tank (1) is fixedly connected to a collection pipe (2301) that is perpendicular to one end of the water purification guide plate (1802). A water pump branch pipe (2302) is provided on the collection pipe (2301) corresponding to each group of two water purification guide plates (1802). The upper end of the water pump branch pipe (2302) is a beveled structure that is obliquely cut towards the end. The end of the circulating water inlet pipe (14) located in the coupling treatment tank (1) is higher than the upper end of the water purification guide plate (1802).

9. A wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor according to claim 1, characterized in that, The ultraviolet disinfection device (24) has an internal installation groove (2401) on one side facing the clear water pool (2). The upper end of the internal installation groove (2401) is a beveled structure. Ultraviolet germicidal lamp tubes (2402) are evenly spaced vertically in the internal installation groove (2401).

10. A wastewater treatment system coupled with an oxygen-enriched membrane reactor and a membrane bioreactor according to claim 1, characterized in that, The inner ring wall of the gas stirring assembly (27) has at least six jet pipes (2701) arranged in a counterclockwise direction. A support frame (2702) is fixedly provided on the gas stirring assembly (27) below the jet pipes (2701). A six-bladed pneumatic stirring impeller (2703) is rotatably connected to the upper middle part of the support frame (2702) through a rotating shaft. The jet direction of the jet pipes (2701) is consistent with the rotation direction of the pneumatic stirring impeller (2703).

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