Anti-fouling type MBR membrane module

Abstract

The utility model provides a kind of anti-fouling type MBR membrane module, through the organic assembly of conventional diaphragm and the intermediate composite diaphragm of anti-fouling device, intermediate composite diaphragm bottom is equipped with anti-fouling device, periodic operation is combined with membrane cleaning agent and compressed air delivery system, and reagent and compressed air are delivered to anti-fouling device, reagent and MBR membrane silk surface pollutant reaction, and remove pollutant by strong air washing.The utility model patent is sequentially assembled by conventional diaphragm and intermediate composite diaphragm, intermediate composite diaphragm is provided with anti-fouling device, periodic operation, effectively reduce the pollution of MBR membrane silk, slow down the offline cleaning cycle of MBR membrane, and then prolong the service life of MBR membrane.

Description

Technical Field

[0001] This invention relates to the field of environmental water treatment technology, and in particular to an antifouling MBR membrane module (GDMAM) for treating wastewater with high sludge concentration. Background Technology

[0002] MBR membrane technology has advantages such as small footprint, low effluent turbidity, and high pollutant degradation efficiency, and has been widely used in many fields such as municipal wastewater, chemical wastewater, agricultural wastewater, pharmaceutical wastewater, and electroplating wastewater. However, MBR membrane fouling causes difficulties for users and high cleaning and maintenance costs, which is an important problem restricting the promotion and application of MBR technology.

[0003] In some high-concentration wastewaters, sludge concentrations can typically reach 8000-12000 mg / L. After 2-3 months of operation, the transmembrane pressure difference of an MBR membrane system reaches 25-30 kPa. A certain amount of microorganisms, organic matter, and other pollutants adhere to the surface of the MBR membrane fibers. While the membrane fiber fouling is not yet severe, after another 1-2 months of operation, the transmembrane pressure difference will increase to 30-35 kPa, necessitating offline cleaning, which greatly complicates the operation. Many researchers have dedicated themselves to studying MBR membrane fouling control systems and materials. For example, CN202311763833.9 reports an MBR membrane fouling control system, including an MBR membrane system and an MBR membrane fouling dynamic control unit; CN202510185873.2 reports the preparation method and application of materials for inhibiting sludge EPS secretion and mitigating MBR membrane fouling. Essentially, the core issue of MBR membrane fouling is the poor anti-fouling performance of the MBR membrane module.

[0004] Improving the antifouling performance of MBR membrane modules is of great significance for enhancing the operational stability and reducing the maintenance cost of MBR membrane systems. Summary of the Invention

[0005] The purpose of this invention is to provide a fouling-resistant MBR membrane module, GDMAM (Gong Da Mo Anti-pollution MBR), which uses an anti-fouling composite membrane between conventional membranes and an anti-fouling device installed at the bottom. By periodically adding membrane cleaner (MC) and compressed air (CA), membrane fouling is delayed, the offline cleaning cycle of the MBR membrane module is extended, and thus the life of the MBR membrane is extended.

[0006] The technical solution of this invention is: an anti-fouling MBR membrane module, mainly comprising membrane fixing rods, conventional membranes, intermediate composite membranes, an anti-fouling device, a membrane cleaning agent delivery system, and a compressed air delivery system. Specifically, it includes a left conventional membrane, an intermediate composite membrane, a right conventional membrane, an upper inner fixing rod, an upper outer fixing rod, a lower inner fixing rod, and a lower outer fixing rod. The left conventional membrane contains left conventional membrane fibers, the intermediate composite membrane contains intermediate composite membrane fibers, and the right conventional membrane contains right conventional membrane fibers. The membrane sheet is composed of several layers; the lower part of the intermediate composite membrane sheet is the anti-fouling device module area, which is equipped with an anti-fouling device, several sets of anti-fouling spray aeration pipes, and air and liquid inlet pipes for the anti-fouling device; the air and liquid inlet pipes of the anti-fouling device are connected to the membrane cleaning agent MC delivery system and the compressed air CA delivery system; the MC delivery system includes an MC liquid inlet pipe, an MC liquid inlet valve, an MC liquid inlet flow display sensor, and an MC liquid inlet pipe; the CA delivery system includes a CA connection to the anti-fouling device air inlet pipe, a CA air inlet valve, a CA air inlet pressure sensor, and a CA air inlet pipe.

[0007] The lower part of the intermediate composite membrane has a 15-20cm height area for installing anti-fouling devices. The total number of membranes, including the left conventional membrane, the middle composite membrane, and the right conventional membrane, is 10-40, with a membrane spacing of 8-10 cm. Among them, the anti-fouling spray aeration pipe 8 installed in the anti-fouling device is between a conventional membrane and an intermediate composite membrane, and the diameter of the small holes is 0.5-1.5mm, with the opening rate of a single spray pipe being 20%-30%; An anti-fouling MBR membrane module is assembled by alternately installing conventional membrane sheets and intermediate composite membrane sheets on membrane fixing rods. Several spray aeration pipes are installed on the anti-fouling device at the bottom of the intermediate composite membrane sheet, evenly distributed between adjacent membrane sheets. After installation, the module is placed in the MBR membrane tank and operated for two months. Then, the MBR membrane operation system is stopped, and the membrane cleaning agent (MC) delivery system is started. The membrane cleaning agent can be sodium hypochlorite, citric acid, or a composite cleaning agent. The agent concentration is controlled at 1000-2000 ppm, the flow rate at 300-500 L / h, and the delivery time at 5-10 min. The MC delivery system is then stopped, and the compressed air (CA) delivery system is started. The initial pressure is controlled at 20-30 kPa, and the time at 20-30 min. Subsequently, the CA pressure is increased to 0.1-0.2 MPa, and continuous aeration is maintained for 30-45 min. The CA delivery system is then stopped, and the MBR membrane permeate system is restored to operation.

[0008] The working principle of this invention is as follows: When the MBR membrane is running, if the membrane fibers at the bottom of the membrane sheet are already contaminated but have not yet reached a severe level, a reagent is added through a periodic MC delivery system to locally form a high concentration of reagent. This reagent reacts violently with the contaminants on the surface of the membrane fibers at the bottom of the membrane sheet, thus promptly reducing the contaminant concentration. At the same time, through the CA dosing system, under low-pressure CA gas supply, the CM reagent is locally and uniformly mixed and reacts with the contaminants on the membrane fibers, avoiding damage to the membrane fibers. Under high-pressure CA gas supply, the strong gas-water mixing shakes off the contaminants on the surface of the membrane fibers, reducing membrane fiber contamination.

[0009] The technical advantages of this invention are: an anti-fouling MBR membrane module, which differs from traditional membrane modules composed of uniform membrane sheets, is an anti-fouling MBR membrane module. Through the orderly assembly of conventional membrane sheets and intermediate composite membrane sheets, the intermediate composite membrane sheets are equipped with anti-fouling devices and operate periodically, which effectively reduces the fouling of MBR membrane fibers, slows down the offline cleaning cycle of MBR membranes, and thus extends the service life of MBR membranes. Attached image description: Figure 1 This is a schematic diagram of the structure of an anti-fouling MBR membrane module.

[0010] Among them, 1-upper inner fixing rod of diaphragm; 2-upper outer fixing rod of diaphragm; 3-lower inner fixing rod of diaphragm; 4-lower outer fixing rod of diaphragm; 5-left conventional diaphragm; 6-left conventional diaphragm filament; 7-middle composite diaphragm; 8-anti-fouling spray aeration pipe; 9-middle composite diaphragm filament; 10-middle composite diaphragm anti-fouling device module area; 11-anti-fouling device; 12-anti-fouling device air and liquid inlet main pipe; 13-MC liquid inlet pipe; 14-MC liquid inlet valve; 15-MC liquid inlet flow display sensor; 16-MC liquid inlet pipe; 17-CA anti-fouling device air inlet pipe; 18-CA air inlet valve; 19-CA air inlet pressure sensor; 20-CA air inlet pipe; 21-right conventional diaphragm; 22-right conventional diaphragm filament. Detailed implementation method: The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0011] like Figure 1The anti-fouling MBR membrane module shown mainly includes: an inner fixing rod 1 for the upper part of the membrane; an outer fixing rod 2 for the upper part of the membrane; an inner fixing rod 3 for the lower part of the membrane; an outer fixing rod 4 for the lower part of the membrane; a left conventional membrane 5; a left conventional membrane filament 6; a middle composite membrane 7; an anti-fouling spray aeration pipe 8; a middle composite membrane filament 9; an anti-fouling device module area 10 for the middle composite membrane; an anti-fouling device 11; an anti-fouling device air and liquid inlet manifold 12; an MC liquid inlet pipe 13; an MC liquid inlet valve 14; an MC liquid inlet flow display sensor 15; an MC liquid inlet pipe 16; a CA anti-fouling device air inlet pipe 17; a CA air inlet valve 18; a CA air inlet pressure sensor 19; a CA air inlet pipe 20; a right conventional membrane 21; and a right conventional membrane filament 22.

[0012] An antifouling MBR membrane module is assembled with conventional membrane sheets and intermediate composite membrane sheets alternately. The left conventional membrane sheet 5, the intermediate composite membrane sheet 7, and the right conventional membrane sheet 21 are all fixed by upper inner fixing rod 1, upper outer fixing rod 2, lower inner fixing rod 3, and lower outer fixing rod 4. The left conventional membrane sheet 5 contains left conventional membrane sheet filaments 6, the intermediate composite membrane sheet 7 contains intermediate composite membrane sheet filaments 9, and the right conventional membrane sheet 21 contains right conventional membrane sheet filaments 22. The lower region of the intermediate composite membrane sheet 7 is an antifouling layer for the intermediate composite membrane sheet. The anti-clogging device module area 10 is equipped with an anti-clogging device 11, 4-6 sets of anti-clogging spray aeration pipes 8, and an anti-clogging device air and liquid inlet main pipe 12; the anti-clogging device air and liquid inlet main pipe is externally connected to a membrane cleaning agent MC delivery system and a compressed air CA delivery system; the MC delivery system includes an MC liquid inlet pipe 13, an MC liquid inlet valve 14, an MC liquid inlet flow display sensor 15, and an MC liquid inlet pipe 16; the CA delivery system includes a CA anti-clogging device air inlet pipe 17, a CA air inlet valve 18, a CA air inlet pressure sensor 19, and a CA air inlet pipe 20.

[0013] The lower part of the middle composite membrane has a 15cm height area for installing anti-fouling devices. The total number of conventional membranes and intermediate composite membranes is 20, and the membrane spacing is 8cm. Among them, the anti-fouling spray aeration pipe 8 installed in the anti-fouling device 11 is between a conventional membrane and an intermediate composite membrane, with a small hole diameter of 1mm and a single spray pipe opening rate of 25%; The operating steps are as follows: First, shut down the MBR membrane operating system and start the membrane cleaning agent MC delivery system. Sodium hypochlorite is selected as the membrane cleaning agent, with a concentration controlled at 1000 ppm, a flow rate controlled at 500 L / h, and a delivery time controlled at 5 min. The sodium hypochlorite agent sequentially passes through the MC inlet pipe 16, the MC inlet flow display sensor 15, the MC inlet valve 14, and the MC inlet pipe 13, entering the anti-fouling device's air and liquid inlet manifold 12. The sodium hypochlorite then flows through the anti-fouling spray aeration pipe 8, flowing between the left conventional membrane 5 and the intermediate composite membrane 7, and between the right conventional membrane 21 and the intermediate composite membrane 7. Then, the MC delivery system is stopped, and the compressed air CA delivery system is started. CA flows sequentially through the CA air inlet pipe 20, the CA inlet pressure sensor 19, the CA inlet valve 18, and the CA inlet pipe 17 of the antifouling device, and enters the air and liquid inlet pipe 12 of the antifouling device. CA flows out through the antifouling spray aeration pipe 8 to promote the reaction between the reagent and the pollutants on the membrane fiber surface. The initial pressure is controlled at 20 kPa and the time is controlled at 30 min. Then, the CA pressure is increased to 0.2 MPa and aeration is continued for 30 min. Then, the CA delivery system is stopped and the MBR membrane permeate system is restored to operation.

Claims

1. A fouling-resistant MBR membrane module, characterized in that: The anti-fouling MBR membrane module is assembled alternately with conventional membrane sheets and intermediate composite membrane sheets. The left conventional membrane sheet (5), the intermediate composite membrane sheet (7), and the right conventional membrane sheet (21) are all fixed by the upper inner fixing rod (1), the upper outer fixing rod (2), the lower inner fixing rod (3), and the lower outer fixing rod (4). The left conventional membrane sheet (5) contains left conventional membrane sheet filaments (6), the intermediate composite membrane sheet (7) contains intermediate composite membrane sheet filaments (9), and the right conventional membrane sheet (21) contains right conventional membrane sheet filaments (22). The lower part of the intermediate composite membrane sheet (7) is the intermediate composite membrane sheet. The anti-fouling device module area (10) is equipped with an anti-fouling device (11), 4-6 sets of anti-fouling spray aeration pipes (8) and anti-fouling device air and liquid inlet pipes (12); the anti-fouling device air and liquid inlet pipes are connected to the membrane cleaning agent MC delivery system and the compressed air CA delivery system; the MC delivery system includes an MC liquid inlet pipe (13), an MC liquid inlet valve (14), an MC liquid inlet flow display sensor (15) and an MC liquid inlet pipe (16); the CA delivery system includes a CA connection to the anti-fouling device air inlet pipe (17), a CA air inlet valve (18), a CA air inlet pressure sensor (19) and a CA air inlet pipe (20).

2. A fouling-resistant MBR membrane module as described in claim 1, characterized in that: A 15-20cm height area is left at the bottom of the intermediate composite membrane (7) for installing the anti-fouling device (11).

3. A fouling-resistant MBR membrane module as described in claim 1, characterized in that: The total number of membranes (5) on the left, (7) on the middle, and (21) on the right is 10-40, and the distance between the membranes is 8-10 cm.

4. A fouling-resistant MBR membrane module as described in claim 1, characterized in that: The anti-fouling spray aeration pipe (8) installed in the anti-fouling device (11) is located between the left conventional membrane (5), the middle composite membrane (7) and the right conventional membrane (21). The diameter of the small hole is 0.5-1.5mm, and the opening rate of a single spray pipe is 20%-30%.

5. A fouling-resistant MBR membrane module as described in claim 1, characterized in that: The membrane cleaning agent MC can be any one of sodium hypochlorite, citric acid, or a composite cleaning agent. The agent concentration should be controlled at 1000-2000 ppm, the flow rate at 300-500 L / h, and the delivery time at 5-10 min.

6. A fouling-resistant MBR membrane module as described in claim 1, characterized in that: The compressed air (CA) delivery system has an initial pressure control of 20-30 kPa and a time control of 20-30 min. Subsequently, the CA pressure is increased to 0.1-0.2 MPa, and aeration is continued for 30-45 min.

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