CN201172631Y - A high-flux low-pressure membrane module for sewage treatment MBR process - Google Patents

Abstract

The utility model provides a large-flux low-pressure membrane module used in the sewage treatment MBR process. The module is composed of a plurality of diaphragms. The single diaphragm includes a pair of diaphragms. The aperture of the template is 1-50mm. Micron, the distance between the membrane plates is 4-6mm, supported by the membrane frame. The plurality of diaphragms are fixed parallel to each other on the support of the membrane module to form the whole of the membrane module. A water outlet hole is arranged on the upper part of the membrane sheet, and the water outlet hole is connected with the water collection pipe. diffuser pipe. The utility model has the effect of increasing the membrane flux in the MBR sewage treatment process by 1-3 times, greatly reducing the number of membrane modules and their supporting equipment, and completely relying on gravity to discharge water, saving equipment investment by 60% and energy consumption by 50% , and can effectively slow down the fouling rate of the membrane and reduce operating costs. The effluent can meet the first-class A standard in China's current sewage treatment plant discharge standard GB 18918-2002, and the suspended solids index in the effluent is below 8mg/L.

Description

A high-flux low-pressure membrane module for sewage treatment MBR process

technical field

The utility model relates to a component of a sewage treatment device, in particular to a large-flux low-pressure membrane assembly used in the sewage treatment MBR process.

Background technique

Membrane Bioreactor (MBR for short) is a new type of high-efficiency sewage treatment and reuse process that organically combines membrane separation technology with traditional sewage biological treatment processes and has been used since the 1990s. field has received extensive attention. The MBR process uses membrane separation technology to replace the secondary settling tank in the traditional activated sludge process, and intercepts activated sludge and macromolecular organic substances, which can not only effectively achieve solid-liquid separation, but also greatly increase the concentration of activated sludge in the reactor. , thus greatly improving the quality of effluent water and reducing the volume of the entire reactor. Compared with the traditional process, the MBR process has the advantages of small footprint, good effluent quality, and small sludge output. However, with the application and popularization of MBR technology, the defects of this technology are becoming more and more obvious, which are mainly manifested in the following aspects.

(1) In most MBR processes, the pores of the membrane are below 1 micron, and the sewage is mainly filtered through the pores of the membrane under the action of the suction pump. The smaller the pores of the membrane itself, the greater the amount of suspended solids in the effluent. Small, but the greater the resistance encountered when the filtered water passes through the membrane, the greater the suction pressure required, and the higher the energy consumption.

(2) Due to the small pores of the membrane used in the current MBR process, the amount of water that can be filtered per unit membrane surface area is largely limited (the membrane flux Flux is usually only 0.2-0.5m ³ /m ² /d) , resulting in a large number of membrane modules used in the process, increasing equipment investment, and limiting the promotion and use of the MBR process.

(3) Since the sewage filtration in the current MBR process is mainly completed by the forced interception of the physical membrane, it is easy to cause the clogging of the membrane, requiring regular cleaning, and some even require daily flushing and maintenance, which increases the operating cost and limits Promote the promotion and use of MBR.

(4) The effluent index of the current MBR process is much better than the current sewage treatment discharge standards stipulated by various countries. For example, China's current highest discharge indicator for sewage treatment plants is Class A standard, in which the requirement for suspended solids is 10mg/L, while in MBR effluent indicators, the concentration of suspended solids is basically less than 1mg/L.

Summary of the defects of the MBR process: the effluent is too good, the investment is too large, and the energy consumption is too high.

Contents of the invention

In order to solve the problems existing in the above-mentioned technologies, the purpose of this utility model is to provide a high-flux low-pressure membrane module used in the MBR process of sewage treatment. Under the premise of the highest standard (Class A standard), the investment is only 40% of the current MBR technology investment, and the energy consumption is only 50% of the current MBR technology energy consumption.

In order to achieve the above purpose, the technical solution of the utility model is to provide a large-flux low-pressure membrane module for sewage treatment MBR process, wherein: the module 16 is composed of a plurality of diaphragms 2, and the single membrane The sheet 2 includes a pair of porous membrane plates 3 , the pore size of the template 3 is 1-50 microns, and the distance between the membrane plates 3 is 4-6 mm, supported by the membrane frame 4 . The plurality of diaphragms 2 are fixed parallel to each other on the membrane module support 7 to form the whole of the membrane module 16. A water outlet hole 1 is arranged on the top of the membrane module 2, and the water outlet hole 1 communicates with the water collecting pipe 6. In the membrane module 16 The lower part of the membrane module 16 is provided with a diffuser pipe 8 that supplies air to the membrane module 16 .

Effect of the utility model is embodied in the following aspects:

(1) The aperture of the physical membrane provided by the utility model is 1-50 microns, which is much larger than the apertures of the membranes of all current MBR process manufacturers, and the membrane flux is improved by 1-3 times. The MBR process of this technology can The number of membrane modules and their supporting equipment is greatly reduced, and the equipment investment is only 40% of the existing MBR process.

(2) The MBR process of this technology can not only reduce the number of operating equipment, but also

(2) The MBR process of this technology can not only reduce the number of operating equipment, but also do not need the forced action of the suction pump to discharge water, relying entirely on gravity to discharge water, the energy consumption is only 50% of the existing MBR process, and can effectively slow down The fouling speed of the physical membrane reduces the operating cost.

(3) Using the MBR process of this technology, the filtration mechanism is different from the existing MBR process. It mainly relies on the physical membrane, that is, the biofilm on the surface of the membrane plate to filter the solid pollutants in the sewage, and does not rely on the physical membrane at all. The physical membrane has two functions in the present invention, one is as an isolation layer for sewage and filtered water; the other is as a supporting layer for the biological layer on the surface of the membrane.

(4) The effluent of the MBR using this technology can reach the highest standard in China's current sewage treatment plant discharge standard GB 18918-2002, that is, the first-level A standard, and the index of suspended solids (SS) in the effluent is 8mg /L or less.

Description of drawings

Fig. 1 Fig. 2 is the front view side view of single membrane frame structure of the present utility model;

Fig. 2 is a structural schematic diagram of the membrane module of the present invention;

Fig. 3 is the embodiment example of the utility model;

Fig. 4 is a schematic diagram of the device structure of the present invention.

In the figure: 1. Outlet hole 2. Diaphragm 3. Membrane plate 4. Membrane frame

5. Biofilm 6. Water collection pipe 7. Membrane module support 8. Air diffuser pipe

9. Water inlet pipe 10. Fine grille 11. Denitrification pool 12. Submersible mixer

13. Submersible pump 14. Nitrification tank 15. Microporous aerator 16. Membrane module

17. Regulating valve 18. Outlet pipe 19. Return pipe 20. Aeration blower

21. Membrane blower 22. Electric control device

Detailed ways

The application process of a large-flux low-pressure membrane module used in the sewage treatment MBR process of the present utility model will be described in conjunction with the accompanying drawings and embodiments. In the utility model, when the large-flux low-pressure membrane module is used for the sewage treatment of the MBR process, the solid pollutants in the sewage are mainly filtered by the biofilm attached to the surface of the membrane plate, rather than relying on the membrane plate. The membrane plate is used in the utility model It is only used as the isolation layer of sewage and filtered water and the support layer of biofilm.

As shown in Figures 1, 2, and 3, a large-flux low-pressure membrane module used in the MBR process of sewage in the utility model is composed of a plurality of diaphragms 2, and the single diaphragm 2 includes a pair of For the porous membrane plate 3, the aperture of the template 3 is 1-50 microns, and the distance between the membrane plates 3 is 4-6 mm. It is supported by the membrane frame 4. The plurality of diaphragms 2 are fixed parallel to each other on the membrane module support 7 to form the whole of the membrane module 16. A water outlet hole 1 is arranged on the top of the membrane module 2. The water outlet hole 1 communicates with the water collection pipe 6. In the membrane module 16 The lower part of the membrane module 16 is provided with a diffuser pipe 8 that supplies air to the membrane module 16 .

Fig. 4 is the specific embodiment of the utility model.

When the sewage enters the fine grid 10 from the water inlet pipe 9, it enters the denitrification tank 11 again. In order to prevent sludge from settling, a submersible mixer 12 is installed in the denitrification tank 11 . The denitrified sewage is lifted into the nitrification tank 14 through the submersible pump 13, and the microporous aerator 15 is installed in the nitrification tank to provide oxygen when the sewage is nitrified. A membrane module 16 is also installed in the nitrification tank 14. During sewage treatment, a biofilm 5 with a thickness of several microns grows on the surface of the membrane plate 3. After the sewage is filtered through the surface of the biofilm 5, the filtered water passes through the membrane plate 3 and enters the membrane frame. 4, the filtered water in the membrane frame 4 enters the water collection pipe 6 through the water outlet hole 1 under the action of the upper water pressure of the membrane plate 3 (about 0.5mH ₂ O pressure). Then it is discharged through the outlet pipe 18 connected with the water collecting pipe 6. A water volume regulating valve 17 is installed on the outlet pipe 18, through which the water outlet flow (membrane flux) of the entire membrane module 16 can be controlled.

When the pore diameter of the membrane plate 3 is 20-40 microns, the membrane module 16 can achieve a very high flux, and a stable biofilm 5 can be formed on the membrane plate 3 to effectively retain solid pollutants. Between the nitrification tank 14 and the denitrification tank 11, a return pipe 19 is installed, and its function is to return the nitrified water to the denitrification tank 11 for denitrification. The blower 20 is a blower for aeration, and mainly provides air for the microporous aerator 15 . Blower 21 is a blower for the diffuser pipe 8 on the membrane module 16, which mainly provides air for diffuser for the membrane module 16. By adjusting the gas volume and pressure of the air, the shear force of the air on the biofilm on the membrane surface can be adjusted, thereby adjusting the biofilm. The thickness of the membrane can achieve the purpose of adjusting the filtration capacity of the membrane. The electric control device 22 is the control system of the whole device.

Claims (2)

1. A high-flux low-pressure membrane module for the MBR process in sewage treatment, characterized in that: the module (16) is composed of a plurality of diaphragms (2), and the single diaphragm (2) includes a For the porous membrane plate (3), the pore diameter of the template (3) is 1-50 microns, and a certain interval is provided between the membrane plates (3), which are supported by the membrane frame (4). The outside of the membrane plate (3) A layer of biofilm (5) is attached to it, and the plurality of diaphragms (2) are fixed on the support (7) of the membrane module in parallel to form the whole of the membrane module (16). There is a water outlet hole (1), and the water outlet hole (1) communicates with the water collection pipe (6), and an air diffuser pipe (8) for feeding air to the membrane module (16) is provided at the bottom of the membrane module (16). 2. A large-flux low-pressure membrane module for sewage treatment MBR process according to claim 1, characterized in that: the interval between the membrane plates (3) is 4-6mm.

Images