External anaerobic membrane biological reaction device

Abstract

The utility model relates to the technical field of sewage treatment, and discloses an external anaerobic membrane biological reaction device which comprises a reflux tank, an anaerobic tank, a water outlet tank, an MBR (Membrane Biological Reactor) membrane component and a clear water tank which are connected in sequence, and further comprises a chemical cleaning tank for conveying chemical cleaning liquid to the MBR membrane component, wherein the low-concentration wastewater is fed into the return tank, the effluent of the return tank is conveyed into the anaerobic tank through the return tank sewage lifting pump, the effluent of the anaerobic tank automatically flows into the water outlet tank, and the effluent of the water outlet tank is conveyed into the MBR membrane component through the water outlet tank sewage lifting pump. According to the external anaerobic membrane biological reaction device provided by the utility model, the MBR membrane component is external, the external membrane component is easy to clean and maintain, and microorganisms intercepted on the membrane surface can directly return to the flow tank. Water cleaning and chemical cleaning are adopted for membrane pollution, so that the membrane pollution rate is effectively reduced, the MBR system treatment efficiency is improved, the water quality is kept stable, the economic cost is reduced, and finally, the effluent can be recycled.

Description

Technical Field

[0001] The utility model relates to the technical field of sewage treatment, in particular to an external anaerobic membrane bioreactor. Background Art

[0002] The anaerobic membrane bioreactor (AnMBR) combines anaerobic treatment with membrane separation to separate the hydraulic retention time (HRT) and the sludge retention time (SRT), effectively making up for the shortcomings of traditional anaerobic biological treatment technology. It has the advantages of large biomass, high effluent quality, low sludge production, relatively stable process, and easy automated management. It is an ideal technology for anaerobic biological treatment of low-concentration wastewater.

[0003] The patent document of Chinese patent CN218579762 U discloses an anaerobic membrane bioreactor for wastewater treatment, including an anaerobic tank and an MBR membrane pool. The MBR membrane is placed in the MBR membrane pool, which will cause double pollution of the membrane surface and membrane pores. An aeration fan is used to blow the membrane surface, resulting in high energy consumption and high cost. The membrane pore pollution causes a decrease in flux, affecting the effluent water quality.

[0004] Therefore, it is necessary to propose an external anaerobic membrane bioreactor to at least partially solve the problems existing in the prior art. Utility Model Content

[0005] In order to improve the above problems, the utility model discloses an external anaerobic membrane bioreactor. The MBR membrane assembly is external, and the external membrane assembly is easy to clean and maintain. The microorganisms trapped on the membrane surface can be directly returned to the flow tank. Membrane pollution is treated by water cleaning and chemical cleaning, which effectively reduces the membrane pollution rate, improves the treatment efficiency of the MBR system, maintains stable water quality, reduces economic costs, and ultimately enables the effluent to be used as a resource. It includes a reflux tank, an anaerobic tank, an outlet tank, an MBR membrane assembly and a clean water tank connected in sequence, and also includes a chemical cleaning tank for conveying chemical cleaning liquid to the MBR membrane assembly;

[0006] Among them, low-concentration wastewater is sent to the reflux tank, the effluent of the reflux tank is transported to the anaerobic tank through the reflux tank sewage lifting pump, the effluent of the anaerobic tank flows into the outlet tank by gravity, and the effluent of the outlet tank is transported to the MBR membrane assembly through the pipeline with the outlet tank sewage lifting pump.

[0007] Preferably, a reflux tank level gauge is installed on the reflux tank, and the reflux tank level gauge is used to detect the water level in the reflux tank. The reflux tank level gauge is interlocked with the reflux tank sewage lifting pump.

[0008] Preferably, the anaerobic tank is also equipped with a sewage return pipe connected to the return tank, and the upper sewage in the anaerobic tank flows from the sewage return pipe to the return tank and enters the bottom of the return tank along the tangential direction.

[0009] Preferably, a water outlet tank level gauge is installed on the water outlet tank, and the water outlet tank level gauge is used to detect the water level in the water outlet tank. The water outlet tank level gauge is interlocked with the water outlet tank sewage lifting pump.

[0010] Preferably, the MBR membrane assembly includes an MBR membrane assembly 1 and an MBR membrane assembly 2, which are used in combination and are reserved. The MBR membrane assembly 1 and the MBR membrane assembly 2 have the same structure. The MBR membrane assembly 1 includes a lower water inlet, an upper cleaning inlet, a top concentrated water inlet and a lower cleaning inlet. The sewage lifting pump in the water outlet tank is connected to the lower water inlet, the upper clean water inlet is connected to the clean water tank, the upper cleaning inlet and the lower cleaning inlet are connected to the chemical cleaning tank, and the top concentrated water inlet is connected to the reflux tank.

[0011] Preferably, a valved pipeline 1 connected to the chemical cleaning tank is provided on the connecting pipeline between the upper cleaning inlet and the clean water tank. Valved pipeline 1 is used to add water to the chemical cleaning tank. Valved pipeline 1 is provided with valved pipeline 2 connected to the reflux tank. The sewage lifting pump pipeline of the water outlet tank is connected to valved pipeline 2 through a bypass pipeline.

[0012] Preferably, a clean water tank level gauge is installed on the clean water tank, and the clean water tank level gauge is used to detect the water level in the clean water tank. The clean water tank level gauge is interlocked with the clean water tank sewage lifting pump.

[0013] Preferably, a chemical cleaning tank level gauge is installed on the chemical cleaning tank, which is used to detect the water level in the chemical cleaning tank. The chemical cleaning tank is connected to the upper cleaning inlet and the lower cleaning inlet respectively through a pipeline with a chemical cleaning tank agent lifting pump. The chemical cleaning tank agent lifting pump is used to transport sewage. The outlet pipeline of the clean water tank is bypassed and connected to a pipeline with a clean water tank sewage lifting pump connected to the pipeline with the chemical cleaning tank agent lifting pump. The clean water tank sewage lifting pump is used to transport chemical cleaning liquid. The chemical cleaning tank level gauge is interlocked with the chemical cleaning tank agent lifting pump.

[0014] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0015] (1) The upper sewage of the anaerobic tank reaction device flows to the return tank by gravity and enters the bottom of the return tank along the tangent direction, which is conducive to the sludge brought out by the clean water to settle at the bottom of the return tank and be transported to the anaerobic tank by the return tank sewage lifting pump. The sludge is sent into the anaerobic tank to ensure the sludge concentration in the anaerobic tank.

[0016] (2) The MBR membrane components are external, which is easy to clean and maintain. The microorganisms retained on the membrane surface can be directly returned to the reflux tank.

[0017] (3) Membrane cleaning uses water cleaning and chemical cleaning to effectively reduce the membrane fouling rate, thereby improving the treatment efficiency of the MBR system, maintaining stable water quality, reducing economic costs, and ultimately enabling the effluent to be utilized as a resource. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is a schematic diagram of the structure of an external anaerobic membrane bioreactor of the utility model;

[0020] Figure 2 The utility model is a schematic diagram of the structure of an MBR membrane component in an external anaerobic membrane biological reactor.

[0021] In the figure: 1. Reflux tank; 2. Reflux tank level gauge; 3. Reflux tank sewage lifting pump; 4. Anaerobic tank; 5. Outlet tank; 6. Outlet tank level gauge; 7. Outlet tank sewage lifting pump; 8. MBR membrane assembly 1; 9. MBR membrane assembly 2; 10. Lower water inlet; 11. Upper cleaning inlet; 12. Top concentrated water inlet; 13. Lower cleaning inlet; 14. Clean water tank; 15. Clean water tank level gauge; 16. Clean water tank sewage lifting pump; 17. Chemical cleaning tank; 18. Chemical cleaning tank level gauge; 19. Chemical cleaning tank reagent lifting pump. DETAILED DESCRIPTION

[0022] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] Example

[0024] The utility model will be further described below in conjunction with the accompanying drawings.

[0025] like Figure 1 to Figure 2 As shown, the utility model provides an external anaerobic membrane bioreactor, comprising: a reflux tank 1, an anaerobic tank 4, a water outlet tank 5, an MBR membrane assembly 1 8, an MBR membrane assembly 2 9, a clean water tank 14, and a chemical cleaning tank 17 connected in sequence by a plurality of pipes.

[0026] The reflux tank 1 is provided with a reflux tank level gauge 2 and a reflux tank sewage lifting pump 3. The reflux tank level gauge 2 is used to detect the water level in the reflux tank 1. The reflux tank sewage lifting pump 3 is used to transport sewage to the anaerobic tank 4. The reflux tank level gauge 2 is interlocked with the reflux tank sewage lifting pump 3. The start and stop of the pump is controlled according to the liquid level of the reflux tank 1. When the liquid level is lower than the designed low water level, the reflux tank sewage lifting pump 3 is automatically closed through the automatic control system. When the liquid level is higher than the designed high water level, the reflux tank sewage lifting pump 3 is automatically opened through the automatic control system.

[0027] The water inlet of the anaerobic tank 4 is transported by the reflux tank sewage lifting pump 3. The rising flow rate of the wastewater in the anaerobic tank 4 is controlled at 1.5m / h through internal hydraulic circulation, so that the sludge in the system is in a swelling state, strengthening the contact and mass transfer between the wastewater and the microorganisms, and improving the removal effect of pollutants.

[0028] The effluent of the anaerobic tank 4 flows by gravity to the water outlet tank 5. The water outlet tank 5 is provided with a water outlet tank level gauge 6 and a water outlet tank sewage lifting pump 7. The water outlet tank level gauge 6 is used to detect the water level in the water outlet tank 5. The water outlet tank sewage lifting pump 7 is used to transport sewage to the MBR membrane assembly 8. The water outlet tank level gauge 6 is interlocked with the water outlet tank sewage lifting pump 7. The start and stop of the pump is controlled according to the liquid level of the water outlet tank 5. When the liquid level is lower than the designed low water level, the water outlet tank sewage lifting pump 7 is automatically closed through the automatic control system. When the liquid level is higher than the designed high water level, the water outlet tank sewage lifting pump 7 is automatically opened through the automatic control system.

[0029] The sewage lifting pump 7 of the outlet tank is used to transport sewage to the lower water inlet 10, and solid-liquid separation is carried out under the drive of pressure. The clean water that passes through the membrane enters the clean water tank 14 through the upper cleaning inlet 11, and the concentrated liquid returns to the reflux tank 1 through the top concentrated water outlet 12 and mixes with the raw water before going to the anaerobic tank 4 to continue participating in the reaction.

[0030] The MBR membrane assembly is provided with an MBR membrane assembly 1 8 and an MBR membrane assembly 2 9 of the same structure. When the membrane of the MBR membrane assembly 1 8 is polluted and the membrane flux decreases, the standby MBR membrane assembly 2 9 is started to operate. The MBR membrane assembly adopts a hollow fiber membrane, and the membrane material adopts polyvinylidene fluoride (PVDF) in the organic membrane. The inner diameter of the hollow fiber membrane is 0.7 mm, and the outer diameter of the hollow fiber is 1.2 mm.

[0031] Water cleaning is divided into lower cleaning and upper cleaning. During lower cleaning, the clean water tank sewage lifting pump 16 is started to transport clean water to the lower cleaning inlet 13, and the outlet water is transported to the reflux tank 1 through the top concentrated water outlet 12; after the lower cleaning is completed, it is changed to upper cleaning, and the clean water tank sewage lifting pump 16 is started to transport clean water to the upper cleaning inlet 11, and the outlet water is transported to the reflux tank 1 through the lower water inlet 10.

[0032] Chemical cleaning can be done by acid or alkaline cleaning. Acid cleaning uses 0.1% HCl (which can be increased or decreased appropriately depending on the specific water quality), and alkaline cleaning uses 0.05% NaOH + 0.1% NaOCl (which can be increased or decreased appropriately depending on the specific water quality). A chemical cleaning tank level gauge 18 and a chemical cleaning tank agent lifting pump 19 are provided in the chemical cleaning tank 17. The chemical cleaning tank level gauge 18 is used to detect the water level in the chemical cleaning tank 17. The chemical cleaning tank agent lifting pump 19 is used to transport chemicals to the MBR membrane assembly 8. The chemical cleaning tank level gauge 18 is interlocked with the chemical cleaning tank agent lifting pump 19. The start and stop of the pump is controlled according to the liquid level of the chemical cleaning tank 17. When the liquid level is lower than the designed low water level, the chemical cleaning tank agent lifting pump 19 is automatically closed by the automatic control system. When the liquid level is higher than the designed high water level, the chemical cleaning tank agent lifting pump 19 is automatically opened by the automatic control system.

[0033] Chemical cleaning is divided into lower cleaning and upper cleaning. For lower cleaning, the chemical cleaning tank reagent lifting pump 19 is turned on to transport the reagent to the lower cleaning inlet 13, soak for 1 hour, and the outlet water is sent to the chemical cleaning tank 17 through the lower water inlet 10. For upper cleaning, the chemical cleaning tank reagent lifting pump 19 is turned on to transport the reagent to the upper cleaning inlet 11, and the cleaning cycle is washed for 1 hour, and the outlet water is sent to the chemical cleaning tank 17 through the lower water inlet 10. After chemical cleaning, the cleaning liquid in the MBR membrane assembly and pipeline is drained and repeatedly rinsed with water until the rinse water is neutral.

[0034] The structure of the present invention and the specific operation process of the present invention are described below in conjunction with a specific implementation method of the present invention.

[0035] In a low-concentration wastewater treatment project, the wastewater first enters the reflux tank, and is transported to the anaerobic tank by the reflux tank sewage lift pump. The internal hydraulic circulation controls the rising flow rate of the wastewater in the anaerobic tank at 1.5m / h, so that the sludge in the system is in an expanded state, strengthening the contact and mass transfer between the wastewater and the microorganisms. The upper sewage of the anaerobic tank reaction device flows to the reflux tank by gravity, and is transported to the anaerobic tank by the reflux tank sewage lift pump. The sludge is deposited at the bottom of the anaerobic tank, ensuring the sludge concentration in the anaerobic tank. The effluent of the anaerobic tank flows to the outlet tank by gravity, and the outlet tank sewage lift pump transports the sewage to the MBR membrane assembly for solid-liquid separation. The clean water flows to the clean water tank by gravity, and the concentrated liquid is transported to the reflux tank and mixed with the raw water to the anaerobic tank to continue to participate in the reaction.

[0036] The MBR membrane assembly uses a hollow fiber membrane made of polyvinylidene fluoride. The inner diameter of the hollow fiber membrane is 0.5 mm and the outer diameter of the hollow fiber is 1.0 mm. When the membrane is polluted, it is cleaned underwater and above water. After the water cleaning, it is acid washed with 0.05% HCl. After the acid washing, the cleaning liquid in the MBR membrane assembly and pipeline is drained and repeatedly rinsed with water until the rinse water is neutral.

[0037] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. An external anaerobic membrane bioreactor, characterized in that: It comprises a reflux tank (1), an anaerobic tank (4), a water outlet tank (5), an MBR membrane assembly and a clean water tank (14) which are connected in sequence, and also comprises a chemical cleaning tank (17) for conveying a chemical cleaning liquid to the MBR membrane assembly; The low-concentration wastewater is sent to the reflux tank (1), the effluent of the reflux tank (1) is transported to the anaerobic tank (4) through the reflux tank sewage lifting pump (3), the effluent of the anaerobic tank (4) flows by gravity into the outlet tank (5), and the effluent of the outlet tank (5) is transported to the MBR membrane assembly through a pipeline with the outlet tank sewage lifting pump (7).

2. The external anaerobic membrane bioreactor according to claim 1, characterized in that: A reflux tank level meter (2) is installed on the reflux tank (1). The reflux tank level meter (2) is used to detect the water level in the reflux tank (1). The reflux tank level meter (2) is interlocked with a reflux tank sewage lifting pump (3).

3. The external anaerobic membrane bioreactor according to claim 1, characterized in that: The anaerobic tank (4) is also provided with a sewage return pipe connected to the return tank (1). The upper sewage in the anaerobic tank (4) flows from the sewage return pipe to the return tank (1) and enters the bottom of the return tank (1) along a tangential direction.

4. The external anaerobic membrane bioreactor according to claim 1, characterized in that: A water outlet tank level gauge (6) is installed on the water outlet tank (5). The water outlet tank level gauge (6) is used to detect the water level in the water outlet tank (5). The water outlet tank level gauge (6) is interlocked with the water outlet tank sewage lifting pump (7).

5. The external anaerobic membrane bioreactor according to claim 1, characterized in that: The MBR membrane assembly comprises an MBR membrane assembly 1 (8) and an MBR membrane assembly 2 (9) which are used in one and reserved in another. The MBR membrane assembly 1 (8) and the MBR membrane assembly 2 (9) have the same structure. The MBR membrane assembly 1 (8) comprises a lower water inlet (10), an upper cleaning inlet (11), a top concentrated water inlet (12) and a lower cleaning inlet (13). The sewage lifting pump (7) of the water outlet tank is connected to the lower water inlet (10), the upper cleaning inlet (11) is connected to the clean water tank (14), the upper cleaning inlet (11) and the lower cleaning inlet (13) are connected to the chemical cleaning tank (17), and the top concentrated water inlet (12) is connected to the reflux tank (1).

6. The external anaerobic membrane bioreactor according to claim 5, characterized in that: A valved pipeline 1 connected to a chemical cleaning tank (17) is provided on the connecting pipeline between the upper cleaning inlet (11) and the clean water tank (14). The valved pipeline 1 is used to add water to the chemical cleaning tank (17). The valved pipeline 1 is provided with a valved pipeline 2 connected to the reflux tank (1). The pipeline of the sewage lifting pump (7) of the water outlet tank is connected to the valved pipeline 2 through a bypass pipeline.

7. The external anaerobic membrane bioreactor according to claim 5, characterized in that: A clean water tank level gauge (15) is installed on the clean water tank (14). The clean water tank level gauge (15) is used to detect the water level in the clean water tank (14). The clean water tank level gauge (15) is interlocked with the clean water tank sewage lifting pump (16).

8. The external anaerobic membrane bioreactor according to claim 5, characterized in that: A chemical cleaning tank level meter (18) is installed on the chemical cleaning tank (17). The chemical cleaning tank level meter (18) is used to detect the water level in the chemical cleaning tank (17). The chemical cleaning tank (17) is connected to the upper cleaning inlet (11) and the lower cleaning inlet (13) respectively through a pipeline with a chemical cleaning tank agent lifting pump (19). The chemical cleaning tank agent lifting pump (19) is used to transport chemical cleaning liquid. The outlet pipeline of the clean water tank (14) is bypass-connected with a pipeline with a clean water tank sewage lifting pump (16) connected to the pipeline with the chemical cleaning tank agent lifting pump (19). The clean water tank sewage lifting pump (16) is used to transport clean water. The chemical cleaning tank level meter (18) is interlocked with the chemical cleaning tank agent lifting pump (19).

Images