A side-mounted cross-flow aerated membrane bioreactor

Abstract

The present invention discloses a membrane bioreactor with a side-mounted cross-flow aeration, which relates to the technical field of membrane biological water treatment for domestic or industrial sewage. The membrane bioreactor with a side-mounted cross-flow aeration comprises: a water inlet for inputting incoming water after biochemical treatment; an overflow port for partial backflow of incoming water; a guide pipe for centralized aeration guidance; an aeration chamber for inputting compressed gas; a microporous filter membrane for intercepting and filtering water containing activated sludge and suspended matter; an aeration membrane for generating microbubbles; and a suction port for discharging produced water. Compared with the prior art, the beneficial effects of the present invention are: a bypass configuration is adopted to realize the diversification of the installation methods of the membrane bioreactor, and concentrated aeration is carried out through the guide pipe to prevent suspended matter and bacteria in the water from aggregating and adhering to the surface of the microporous filter membrane. This method has a good interception effect, greatly simplifies the operation and maintenance methods of the membrane bioreactor, improves the water production rate, and greatly reduces the construction and operation costs of the membrane bioreactor.

Description

Technical Field

[0001] The invention relates to the technical field of membrane biological water treatment for domestic or industrial sewage, in particular to a membrane bioreactor (MBR) with a bypass configuration and centralized cross-flow aeration. Background Art

[0002] Traditional membrane bioreactors are arranged in membrane pools and can replace the terminal secondary sedimentation tank in biological treatment technology. Traditional membrane bioreactors use the negative pressure generated by top suction to produce water. The transmembrane pressure is generally 0.016-0.02MPa. It adopts the operation mode of continuous aeration and intermittent water production. The typical operation time is set as follows: 8 minutes of filtration, 2 minutes of pause, 2 minutes of backwashing every 12 hours, and online maintenance cleaning every 7 days, 25 minutes each time. Traditional membrane bioreactors need to build membrane pools, which have high construction costs. Generally, the transmembrane pressure is less than 0.02MPa, so the water production rate is relatively low, and frequent pauses and backwashing are required during operation, which reduces the operating rate. Even with frequent backwashing, the membrane fibers of the membrane bioreactor are inevitably frequently blocked by dirt. Therefore, it is necessary to frequently remove the module from the membrane pool for cleaning or replacement. The cleaning, maintenance or replacement of the module is very labor-intensive and the cost is also very high. Summary of the invention

[0003] The object of the present invention is to provide a side-mounted cross-flow aerated membrane bioreactor to solve the problems mentioned in the above background technology.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A side-mounted cross-flow aeration membrane bioreactor, comprising:

[0006] A water inlet is used to input water that has undergone biochemical treatment;

[0007] Overflow port, used for partial return of incoming water;

[0008] The guide pipe is used to centrally guide aeration;

[0009] an aeration chamber for inputting compressed gas;

[0010] Microporous membranes are used for interception and filtration of water containing activated sludge and suspended solids;

[0011] Aeration membrane for generating microbubbles;

[0012] Suction port, used to discharge produced water.

[0013] As a further solution of the present invention, the overflow port is arranged at the top of the reactor.

[0014] As a further solution of the present invention, a suction port is arranged at the bottom of the reactor.

[0015] As a further solution of the present invention, one or more flow guide tubes are arranged side by side in the reactor, and the microporous filter membrane is installed in the flow guide tube. The clean water filtered by the filter membrane is discharged from the water outlet port at the bottom of the flow guide tube into the water collection chamber and then discharged from the suction port.

[0016] As a further solution of the present invention, an aeration membrane is installed at the lower part of the guide tube near the bottom water outlet port and is enclosed in an aeration chamber. The surface of the aeration membrane is covered with micropores. After the compressed gas enters the aeration chamber, it passes through the micropores on the surface of the aeration membrane to generate microbubbles. After these microbubbles enter the guide tube, they float along the guide tube and the surface of the microporous filter membrane.

[0017] As a further solution of the present invention, the microbubbles floating up through the draft tube carry activated sludge and suspended matter and are discharged through the overflow port.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: the membrane bioreactor proposed in the present invention adopts a bypass configuration and no longer requires a membrane tank. The installation methods of such a membrane bioreactor are more diversified, and the construction, maintenance and operation costs are also greatly reduced. The centralized cross-flow aeration method is adopted to enhance the flotation effect, prevent the activated sludge and suspended matter from adhering to the surface of the membrane filaments, and can also have a certain removal effect on the activated sludge and suspended matter adhering to the surface of the membrane filaments. The bottom suction method is used for water production, which can increase the transmembrane pressure from less than 0.02MPa to more than 0.12MPa, which is equivalent to a six-fold increase in the transmembrane pressure, and can greatly increase the water production rate of the membrane bioreactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the structural principle of a side-mounted cross-flow aerated membrane bioreactor.

[0020] Figure 2 This is a schematic diagram of the process flow of the side-mounted cross-flow aerated membrane bioreactor.

[0021] In the figure: 1-water inlet, 2-overflow port, 3-guide pipe, 4-microporous filter membrane, 5-aeration membrane, 6-aeration chamber, 7-water outlet port at the bottom of the guide pipe, 8-suction port, 9-water collection chamber, 10-compressed gas inlet, 11-check valve, 12-solenoid valve, 13-air inlet filter cap, 14-air compressor, 15-compressed air bag, 16-vacuum tank, 17-water output pump, 18-raw water pump, 19-biochemical reaction tank DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0023] See also Figure 1 , a side-mounted cross-flow aeration membrane bioreactor, comprising:

[0024] Water inlet 1, used for inputting water after biochemical treatment;

[0025] Overflow port 2, used for partial return of incoming water;

[0026] The guide pipe 3 is used to centrally guide aeration;

[0027] Aeration chamber 6, for inputting compressed gas;

[0028] Microporous filter membrane 4, used for intercepting and filtering water containing activated sludge and suspended matter;

[0029] Aeration membrane 5, used to generate microbubbles;

[0030] The suction port 8 is used to discharge the produced water.

[0031] Furthermore, an overflow port 2 is arranged at the top of the reactor.

[0032] Furthermore, a suction port 8 is provided at the bottom of the reactor.

[0033] Furthermore, one or more flow guide tubes 3 are arranged side by side in the reactor, and a microporous filter membrane 4 is installed in the flow guide tube 3. Clean water filtered through the filter membrane is discharged from the water outlet port 7 at the bottom of the flow guide tube into the water collection chamber 9, and then discharged from the suction port 8.

[0034] Furthermore, the aeration membrane 5 is installed at the lower part of the flow guide tube 3 near the bottom water outlet port 7 and is enclosed in the aeration chamber 6. The surface of the aeration membrane 4 is covered with micropores. After the compressed gas enters the aeration chamber 6, it passes through the micropores on the surface of the aeration membrane 5 to generate microbubbles. After these microbubbles enter the flow guide tube 3, they float along the surface of the flow guide tube 3 and the microporous filter membrane 4.

[0035] Furthermore, the microbubbles floating up through the draft tube 3 are discharged through the overflow port 2 along with the activated sludge and suspended matter.

[0036] In this implementation case, see Figure 2The suction port 8 is connected to the vacuum tank 16, and the water output pump 17 is also connected to the vacuum tank 16. The overflow port 2 is connected to the biochemical reaction tank 19. The air in the compressed air bag 15 enters the aeration chamber 6 through the compressed gas inlet 10, and the air compressor 14 inflates the compressed air bag 15.

[0037] Further, the air compressor 14 inflates the compressed air bag 15 to a set high pressure value, and the air compressor 14 stops. When the system starts, the solenoid valve 12 opens, and the air in the compressed air bag 15 enters the aeration chamber 6 through the compressed gas inlet 10. When the pressure of the compressed air bag 15 is lower than the set low pressure value, the air compressor 14 starts. When the system stops, the solenoid valve 12 is closed, and the check valve 11 prevents the water in the water collection chamber 9 from flowing back.

[0038] Furthermore, before the system is started, the vacuum tank 16 is filled with water to exhaust the air therein.

[0039] Furthermore, before the system is started, the water in the biochemical reaction pool is pumped into the membrane bioreactor through the water inlet 1 by the raw water pump 18. When water overflows from the overflow port 2, the system is started, and the produced water export pump 17 is turned on at the same time to export the produced water. The flow rate of the raw water pump 18 is greater than the flow rate of the produced water export pump 17. During the entire process of system operation, the microbubbles floating up through the guide pipe 3 are continuously discharged through the overflow port 2, carrying the activated sludge and suspended matter.

[0040] The working principle of the present invention is as follows: the water after biochemical treatment enters the membrane bioreactor through the raw water pump 18, and the activated sludge and some suspended matter contained in the water enter the membrane bioreactor and encounter the floating microbubbles, which are discharged from the overflow port 2 back to the biochemical reaction tank 19. The water after the upper air flotation continues to flow downward into the guide pipe 2, where it will contact the microporous filter membrane 4, and under the hydraulic pressure difference and the suction action of the water production external delivery pump 17, the water will pass through the surface of the microporous filter membrane 4 and then enter the water collection chamber 9 through the water outlet port 7 at the bottom of the guide pipe 3. After the water after biochemical treatment enters the membrane bioreactor, it will contact the floating microbubbles generated by the aeration membrane 5 during the entire downward flow process. The microbubbles will capture the activated sludge and suspended matter in the water, and carry these activated sludge and suspended oil particles to float together. At the same time, the floating microbubbles in the guide pipe 3 can also clean the surface of the microporous filter membrane 4, which is beneficial to maintain the water flux of the microporous filter membrane 4. Under the hydraulic pressure difference and the suction action of the produced water delivery pump 17 , a relatively high transmembrane pressure difference will be generated, thereby increasing the water production rate of the microporous filter membrane 4 .

[0041] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0042] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A side-mounted cross-flow aeration membrane bioreactor, comprising: A water inlet is used to input water that has undergone biochemical treatment; Overflow port, used for partial return of incoming water; The guide pipe is used to centrally guide aeration; an aeration chamber for inputting compressed gas; Microporous filter membrane is used for intercepting and filtering water containing activated sludge and suspended solids; aeration membrane is used for generating microbubbles; suction port is used for discharging produced water; its characteristics are: The overflow port is arranged at the top of the reactor, and the suction port is arranged at the bottom of the reactor; The reactor is provided with a plurality of flow guide pipes arranged side by side, and the microporous filter membrane is installed in the flow guide pipe. The clean water filtered by the filter membrane is discharged from the water outlet port at the bottom of the flow guide pipe into the water collection chamber, and then discharged from the suction port. The aeration membrane is installed at the lower part of the guide pipe near the bottom water outlet port and is enclosed in an aeration chamber. The surface of the aeration membrane is covered with micropores. After the compressed gas enters the aeration chamber, it generates microbubbles through the micropores on the surface of the aeration membrane. After these microbubbles enter the guide pipe, they float along the guide pipe and the surface of the microporous filter membrane, and are discharged through the overflow port along with the activated sludge suspended matter.

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