CN220861119U - MBR membrane online cleaning device and sewage treatment system - Google Patents

Abstract

The application discloses an MBR (Membrane biological reactor) membrane online cleaning device and a sewage treatment system, and belongs to the technical field of sewage treatment. An online MBR membrane cleaning device is used for cleaning an MBR membrane in a membrane tank and comprises a gas-liquid mixing tank and at least one flushing piece. The gas-liquid mixing tank is provided with a mixing cavity, a liquid inlet, an air inlet and a mixed liquid outlet, wherein the liquid inlet, the air inlet and the mixed liquid outlet are communicated with the mixing cavity, the liquid inlet is communicated with the membrane tank, and the air inlet is communicated with the air source. The flushing piece is provided with a flushing piece inlet and a plurality of flushing piece outlets which are arranged at intervals, the flushing piece inlet is communicated with the mixed liquid outlet, and the flushing piece outlet faces the MBR membrane. According to the online MBR membrane cleaning device, through the dual effects of liquid impact and bubble bursting, dirt on the MBR membrane can be removed better when the MBR membrane is cleaned online.

Description

MBR membrane online cleaning device and sewage treatment system

Technical Field

The application belongs to the technical field of sewage treatment, and particularly relates to an MBR (Membrane biological reactor) membrane online cleaning device and a sewage treatment system.

Background

The MBR membrane has the advantages of small occupied area, good solid-liquid separation effect and the like, and is widely applied to the field of sewage treatment. In the MBR operation process, the membrane pore diameter becomes smaller or is blocked due to adsorption and deposition of impurity particles, colloid particles and solute macromolecules on the surface of the membrane or in the membrane pores caused by physical, chemical or mechanical action with the membrane, so that the membrane flux and the separation characteristic of the membrane are poor, and the MBR membrane needs to be cleaned.

MBR membrane cleaning is classified into on-line cleaning and off-line cleaning. In the related art, when in online cleaning, a cleaning agent is added into an MBR membrane tank for soaking, and meanwhile, the membrane tank bottom is continuously exploded to enable dirt on the surface of membrane wires to fall off, so that the aim of cleaning is achieved, however, dirt on the surface of the MBR membrane cannot be well cleaned.

Disclosure of utility model

The application aims to solve the technical problem that the dirt on the surface of the MBR membrane can not be removed well when the MBR membrane is cleaned on line in the related technology at least to a certain extent. Therefore, the application provides an MBR membrane online cleaning device and a sewage treatment system.

In a first aspect, an online MBR membrane cleaning device provided by an embodiment of the present application is used for cleaning an MBR membrane in a membrane tank, and includes:

The gas-liquid mixing tank is provided with a mixing cavity, a liquid inlet, an air inlet and a mixed liquid outlet, wherein the liquid inlet, the air inlet and the mixed liquid outlet are communicated with the mixing cavity, the liquid inlet is communicated with the membrane tank, and the air inlet is communicated with the air source;

At least one flushing piece is provided with a flushing piece inlet and a plurality of flushing piece outlets which are arranged at intervals, the flushing piece inlet is communicated with the mixed liquid outlet, and the flushing piece outlet faces towards the MBR membrane.

In a second aspect, an embodiment of the present application provides a sewage treatment system, including:

The membrane pool is provided with a storage cavity and a membrane pool liquid outlet communicated with the storage cavity;

MBR membranes, a plurality of MBR membranes are arranged, and a plurality of MBR membranes are arranged at intervals;

According to the online MBR membrane cleaning device provided by the application, the liquid inlet is used for being communicated with the liquid outlet of the membrane tank, and one end of the flushing part, which is provided with the flushing part, is positioned between two adjacent MBR membranes.

The utility model has at least the following beneficial effects:

The online MBR membrane cleaning device comprises a gas-liquid mixing tank, wherein gas and liquid are mixed in the tank, and liquid with bubbles is sprayed out from an outlet of a flushing part. Liquid impact on the MBR membrane, can make the dirt on MBR membrane surface drop, the liquid impact in-process drives the bubble and strikes on the MBR membrane in the lump simultaneously, and bubble contact MBR membrane bursts in the twinkling of an eye, also can make the dirt drop, reaches the purpose of strengthening and clear away the dirt. According to the online MBR membrane cleaning device, dirt can be removed better during online MBR membrane cleaning through the dual effects of liquid impact and bubble bursting.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 shows a schematic structural diagram of the online MBR membrane cleaning device of the present application.

Fig. 2 shows a schematic structural view of a flushing member in one or some embodiments of the application.

Reference numerals: 10-membrane tank, 11-membrane tank liquid outlet, 20-MBR membrane, 30-gas-liquid mixing tank, 31-liquid inlet, 32-air inlet, 33-mixed liquid outlet, 34-medicament adding port, 35-air outlet, 40-flushing piece, 41-main pipe, 411-flushing piece inlet, 42-branch pipe, 421-flushing piece outlet, 50-gas distributor, 60-pH valve detection device, 70-water pump, 80-filter, 90-exhaust valve and 100-switching valve.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that all the directional indicators in the embodiments of the present utility model are only used to explain the relative positional relationship, movement conditions, etc. between the components in a specific posture, and if the specific posture is changed, the directional indicators are correspondingly changed.

In the present utility model, unless specifically stated and limited otherwise, the terms "connected," "affixed," and the like are to be construed broadly, and for example, "affixed" may be a fixed connection, a removable connection, or an integral body; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

Furthermore, descriptions such as those referred to as "first," "second," and the like, are provided for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implying an order of magnitude of the indicated technical features in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.

In the field of sewage treatment and water resource recycling, MBR is also called a Membrane bioreactor (Membrane Bio-Reactor), and the MBR Membrane has the advantages of small occupied area, good solid-liquid separation effect and the like and is widely applied to the field of sewage treatment. In the MBR operation process, the membrane pore diameter becomes smaller or is blocked due to adsorption and deposition of impurity particles, colloid particles and solute macromolecules on the surface of the membrane or in the membrane pores caused by physical, chemical or mechanical action with the membrane, so that the membrane flux and the separation characteristic of the membrane are poor, and the MBR membrane needs to be cleaned.

MBR membrane cleaning is divided into online cleaning and offline cleaning, wherein the online cleaning is to add cleaning agent into an MBR membrane tank for soaking, and simultaneously, the membrane tank bottom is continuously exploded to enable dirt on the surface of membrane wires to fall off, so that the cleaning purpose is achieved. However, in the related art, the online cleaning cannot remove dirt on the surface of the film well. When the online cleaning of the surface dirt accumulation of the MBR membrane for a long time cannot meet the requirement, the membrane needs to be cleaned offline.

In the related art, dirt on the surface of the MBR membrane cannot be removed well during online cleaning. The embodiment of the application provides an MBR (Membrane biological reactor) membrane online cleaning device and a sewage treatment system, which can at least solve the technical problems to a certain extent.

The application is described below with reference to specific embodiments in conjunction with the accompanying drawings:

The embodiment of the application provides an online MBR membrane cleaning device, which is used for online cleaning of an MBR membrane 20 in a membrane tank 10 and comprises a gas-liquid mixing tank 30 and a flushing piece 40.

The gas-liquid mixing tank 30 is provided with a mixing chamber, a liquid inlet 31 communicated with the mixing chamber, an air inlet 32 and a mixed liquid outlet 33, wherein the liquid inlet 31 is communicated with the membrane tank 10, and the air inlet 32 is communicated with an air source.

The flushing member 40 is provided with at least one flushing member inlet 411 and a flushing member outlet 421, the flushing member inlet 411 is communicated with the mixed liquor outlet 33, and the flushing member outlet 421 is directed towards the MBR membrane 20.

After this, the liquid in the membrane tank 10 enters the gas-liquid mixing tank 30, is mixed with the gas in the gas-liquid mixing tank 30, enters the flushing device 40 from the mixed liquid outlet 33 after being mixed, and is ejected from the flushing device outlet 421 to be ejected onto the MBR membrane 20.

The impingement of liquid on the MBR membrane 20 can cause fouling on the MBR membrane 20 to break off. Meanwhile, in the liquid impact process, bubbles are driven to impact on the MBR membrane 20, and the bubbles are instantaneously burst when contacting with the MBR membrane 20, so that dirt is loosened and falls off, and the purpose of cleaning the dirt is enhanced. Under the dual actions of liquid impact and bubble burst, dirt on the MBR membrane 20 can be removed better.

In the related art, during online cleaning, aeration is performed from the bottom of the membrane tank 10, and bubbles burst when rising to contact with the MBR membranes 20, however, the MBR membranes 20 are generally arranged vertically, and part of bubbles directly overflow upwards along the gap between the two MBR membranes 20, so that the bubbles cannot contact with the MBR membranes 20 to burst to remove dirt, and the cleaning effect on the MBR membranes 20 is poor, especially the upper middle part of the MBR membranes 20. After the present application is configured in this way, the outlet 421 of the flushing member faces the MBR membrane 20, and most of the bubbles impacted out will directly impact on the MBR membrane 20, so as to achieve better effects.

Meanwhile, in the related art, when the online cleaning is performed, after the MBR membrane 20 is soaked by the medicament, dirt on the MBR membrane 20 naturally falls off, the falling rate is low, the medicament cannot react with deep dirt in time, and the dirt in a deeper layer is removed. After the application is arranged in this way, the liquid in the membrane pool continuously impacts on the MBR membrane 20 through the flushing part 40, so that the dirt reacted on the MBR membrane 20 can be timely dropped off, the medicament can be timely reacted with deep dirt, the reaction rate of the medicament and the dirt is accelerated, and further, a better cleaning effect is obtained.

The types of the MBR membrane 20 are various, such as ceramic membranes, tubular membranes, hollow fiber membranes, flat plate membranes, etc., and the specific structures of these membranes are known to those skilled in the art, and are not described herein, but the specific types of the MBR membrane 20 are not limited in the present application.

From the above description, it is easy to understand that when the MBR membrane online cleaning device provided by the present application is used, it is necessary to install a water pump at the liquid inlet 31, the mixed liquid outlet 33 or other positions of the gas-liquid mixing tank 30, so that the liquid in the membrane tank 10 continuously flows out into the gas-liquid mixing tank 30, and then is sprayed out from the outlet 421 of the flushing member and flows back into the membrane tank 10.

In some embodiments of the present application, in order to facilitate the use by the user, the MBR membrane in-line cleaning apparatus of the present application includes a water pump 70, and the water pump 70 is installed at the liquid inlet 31 side of the gas-liquid mixing tank 30. So arranged, the liquid in the membrane tank 10 is transferred by the water pump 70 into the mixing chamber, and the gas-liquid mixture in the mixing chamber is discharged from the mixed liquid outlet 33 and ejected from the flushing member outlet 421. In some embodiments of the application, the water pump 70 pressure is 0.8 to 1.0MPa.

Since the liquid ejected from the flushing member outlet 421 is derived from the membrane tank 10, dirt and the like on the MBR membrane 20 come off as the cleaning proceeds, and impurities in the liquid in the membrane tank 10 become large. To prevent clogging of the water pump 70, the flushing device outlet 421, and the like by impurities, a filter 80 is provided on the inlet side of the water pump 70.

In some embodiments of the present application, the filter 80 is a self-cleaning filter that may be automatically cleaned after a period of operation, for greater ease of use. It will be readily appreciated that the aperture of the filter apertures in the filter 80 should be smaller than the aperture of the washout outlet 421 to ensure that impurities in the filtered liquid do not clog the washout outlet 421.

The gas source may be nitrogen, carbon dioxide, etc., and is not limited in the present application. In some embodiments of the present application, the air inlet 32 communicates with compressed air having a pressure of 0.6 to 0.8MPa. Compressed air is easy to obtain, low in price and beneficial to saving on-line cleaning cost.

In order to facilitate uniform mixing of the gas and the liquid in the gas-liquid mixing tank 30, in some embodiments of the present application, the MBR membrane online cleaning device further includes a gas distributor 50, the gas distributor 50 is located in the mixing chamber, and a distributor air inlet of the gas distributor 50 is communicated with the air inlet 32 of the gas-liquid mixing tank 30.

The specific structure of the gas distributor 50 is known to those skilled in the art, and is provided with a plurality of distributor gas outlets, and the gas entering through the distributor gas inlet 32 is discharged from the plurality of distributor gas outlets at the same time and uniformly distributed in the mixing cavity, so that the uniform mixing of the gas and the liquid in the mixing cavity is realized. In some embodiments of the application, the sparger gas outlet aperture is 0.8 to 1mm.

The gas density is less than the liquid density and the gas will float up in the liquid and in some embodiments of the application the gas distributor 50 is positioned at the bottom of the gas-liquid mixing tank 30 with the distributor outlets of the gas distributor 50 facing upwards so that the gas and liquid are in full contact as shown in figure 1.

The flushing member 40 discharges the mixed liquid discharged from the mixed liquid outlet 33 through the plurality of flushing member outlets 421 to increase the spray pressure and uniformly spray the mixed liquid on the MBR membrane 20. In some embodiments of the application, the washout piece outlet 421 has a pore size of 3-4 mm. The structure of the flushing member 40 is various, and the specific structure is not limited in the present application, and the structure may be similar to that of the shower head, including a water outlet plate, a water outlet nail, a water diversion plate, a back plate, etc.

In some embodiments of the present application, as shown in fig. 2, the flushing member 40 includes a main pipe 41 and a plurality of branch pipes 42 communicating with the main pipe 41, the flushing member inlet 411 is provided at a side of the main pipe 41 remote from the branch pipes 42, one end of the branch pipe 42 remote from the main pipe 41 is closed, and the flushing member outlet 421 is provided at a side wall of the side of the branch pipe 42 remote from the main pipe 41. The main pipe 41 and the branch pipe 42 are made of various materials such as PPR, PVC, copper, stainless steel, and the like. The design that the flushing part 40 is connected with the branch pipe 42 through the main pipe 41 simplifies the structure of the flushing part 40, is convenient for users to purchase the pipe for processing by themselves, and is beneficial to saving the cost.

In some embodiments of the present application, an on-off valve 100 is provided on the main tube 41 of each flushing member 40.

When the online cleaning is performed after the arrangement, the operation of each flushing piece 40 can be independently controlled, and different operation states can be realized, for example, when the fouling of the MBR membrane 20 is serious, all the switch valves 100 are opened, all the flushing pieces 40 work, and the fouling cleaning rate is accelerated; when the fouling of a part of the MBR membrane 20 is serious, the corresponding switch valve 100 can be selectively opened, so that the part of the flushing member 40 operates, and the cleaning effect is ensured while the energy is saved. After such setting, the on-off valve 100 can be opened sequentially according to the time sequence set in the working process of the MBR membrane 20, so as to flush the MBR membrane 20 in the working process, and reduce the adhesion of dirt in the working process to a certain extent. Meanwhile, after the arrangement, the flushing parts 40 are independent from each other, and when the branch pipe 42 of one flushing part 40 is damaged, the switch valve 100 on the flushing part 40 can be closed, so that the normal operation of other flushing parts 40 is not affected.

In the case of online cleaning, it is necessary to add an acid, alkali or other chemical agent into the membrane tank 10 to cause the fouling reaction on the membrane to fall off.

In some embodiments of the present application, the gas mixing tank 30 is further provided with a medicament addition port 34 communicating with the mixing chamber. After the arrangement, the medicament is added in the mixing cavity and mixed with the liquid in the mixing cavity, and then sprayed out from the outlet 421 of each flushing part to be uniformly sprayed around the MBR membrane 20, so that the medicament and the liquid in the membrane tank 10 are uniformly mixed, and the medicament and the dirt reaction on the MBR membrane 20 are accelerated.

The number of the medicine adding ports 34 may be one or plural, and when plural kinds of medicines are added through the same port, one medicine adding port 34 may be provided, and when medicines are added through different ports, plural medicine adding ports 34 may be provided.

In some embodiments of the application, two medicament addition ports 34 are provided, one in communication with the acid addition device and the other in communication with the base addition device, for regulating the ph in the membrane tank 10. The acid adding device and the alkali adding device are automatic adding devices, the structure of the automatic adding device is known to those skilled in the art, the acid and alkali adding accuracy is guaranteed, and meanwhile labor is saved.

In some embodiments of the present application, the ph detecting means 60 is provided on the liquid inlet 31 side of the gas-liquid mixing tank 30. Is used for detecting the pH value of the liquid in the membrane tank 10 and provides reference for adding acid and alkali. In some embodiments of the present application, pH sensing device 60 is a pH meter.

In some embodiments of the present application, the gas-liquid mixing tank 30 is further provided with an exhaust port 35 in communication with the mixing chamber, and the MBR membrane online cleaning device of the present application further comprises an exhaust valve 90 for controlling the opening and closing of the exhaust port 35. Specifically, the exhaust port 35 is provided at the upper portion of the mixing chamber.

The gas entering through the gas inlet 32 is not necessarily completely carried out by the liquid entering through the liquid inlet 31, and may have a part of gas residue accumulated on the upper part of the gas-liquid mixing tank 30, and the arrangement of the gas outlet 35 and the gas outlet valve 90 can enable the gas to be discharged, so as to maintain the gas-liquid balance in the mixing cavity.

Based on the same inventive concept, the embodiment of the application also provides a sewage treatment system, which comprises a membrane tank 10, an MBR membrane 20 and the MBR membrane online cleaning device provided by the application. The membrane tank 10 is provided with a storage cavity and a membrane tank liquid outlet 11 communicated with the storage cavity; the MBR membranes 20 are arranged in a plurality, and the plurality of MBR membranes 20 are arranged at intervals; the liquid inlet 31 of the online MBR membrane cleaning device provided by the application is communicated with the liquid outlet 11 of the membrane tank, and one end of the flushing piece 40, provided with the flushing piece outlet 421, is positioned between two adjacent MBR membranes 20. In the present application, a plurality of flushing members 40 are provided, and the flushing members 40 are respectively located between the adjacent MBR membranes (20) to flush the MBR membranes 20.

Because the sewage treatment system adopts the online MBR membrane cleaning device provided by the application, dirt on the surface of the MBR membrane 20 can be effectively removed when the sewage treatment system is used for online cleaning.

The manner of fixing the MBR membrane 20, the connection between the MBR membrane 20 and other structures in the sewage treatment system, etc. are well known to those skilled in the art, and thus, will not be described herein. Typically, the MBR membrane 20 is mounted on a membrane holder that is coupled to a mounting structure within the membrane tank 10.

As the MBR membrane in the present application is cleaned by the online cleaning device, dirt and the like on the MBR membrane 20 gradually drop off, impurities in the liquid in the membrane tank 10 become more, and the impurities gradually precipitate and accumulate at the lower part of the membrane tank 10, so in some embodiments of the present application, the membrane tank liquid outlet 11 is located at the upper part of the storage cavity, and the membrane tank liquid outlet 11 is prevented from being blocked by impurities at the lower part of the membrane tank 10.

The application provides an online MBR membrane cleaning device, which adopts the working principle that: when the MBR membrane 20 needs to be cleaned online during running for a period of time, a water pump 70, a filter 80 and an air source communicated with the air inlet 32 are started, a medicament is added into the mixing cavity, the water pump 70 drives liquid in the membrane tank 10 to enter the mixing cavity to be mixed with air, the mixed air-liquid mixture is driven to be discharged from a mixed liquid outlet and enters the flushing part 40, then the flushing part is sprayed out from the flushing part outlet 421, dirt sprayed on the MBR membrane 20 falls off under the combined action of liquid impact and bubble burst. In the operation process of the MBR membrane 20, the on-off valve 100 can be sequentially opened according to a set time sequence to flush the MBR membrane 20 in the operation process, so that dirt adhesion in the operation process is reduced to a certain extent.

In summary, the MBR membrane online cleaning device of the present application includes the gas-liquid mixing tank 30, in which the gas and the liquid are mixed, and the liquid having bubbles is ejected from the rinsing member outlet 421. Liquid impact on the MBR membrane 20 can make the dirt on the surface of the MBR membrane 20 drop, and meanwhile, in the liquid impact process, bubbles are driven to impact on the MBR membrane 20 together, and the bubbles contact the MBR membrane to burst instantly, so that the dirt drops, and the purpose of reinforcing and removing the dirt is achieved. According to the online MBR membrane cleaning device, dirt can be removed better during online MBR membrane cleaning through the dual effects of liquid impact and bubble bursting. The design of the gas distributor 50 helps to uniformly mix the gas and the liquid in the mixing chamber, thereby enhancing the dirt removal effect of the application. The design that the flushing part 40 is connected with the branch pipe 42 through the main pipe 41 simplifies the structure of the flushing part 40, is convenient for users to purchase the pipe for processing by themselves, and is beneficial to saving the cost. The on-off valve 100 enables the flushing member 40 to be operated in different states, enabling each flushing member 40 to be operated independently. The exhaust port 35 and the exhaust valve 90 are arranged to exhaust the gas accumulated at the upper part of the mixing chamber, so as to maintain the gas-liquid balance in the mixing chamber.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Further, one skilled in the art can engage and combine the different embodiments or examples described in this specification.

In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present application.

While embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the application, the scope of which is defined by the claims and their equivalents.

Claims (10)

1. An online belt cleaning device of MBR membrane for wash MBR membrane (20) in membrane pond (10), its characterized in that includes:

The gas-liquid mixing tank (30) is provided with a mixing cavity, and a liquid inlet (31), an air inlet (32) and a mixed liquid outlet (33) which are communicated with the mixing cavity, wherein the liquid inlet (31) is used for being communicated with the membrane tank (10), and the air inlet (32) is used for being communicated with an air source;

At least one flushing member (40), the flushing member (40) is provided with a flushing member inlet (411) and a plurality of flushing member outlets (421) which are arranged at intervals, the flushing member inlet (411) is communicated with the mixed liquid outlet (33), and the flushing member outlet (421) faces towards the MBR membrane (20).

2. The MBR membrane online cleaning device according to claim 1, further comprising a gas distributor (50), the gas distributor (50) being located in the mixing chamber, a distributor inlet of the gas distributor (50) being in communication with the inlet (32).

3. The MBR membrane online cleaning device according to claim 1, wherein the flushing member (40) comprises a main pipe (41) and a plurality of branch pipes (42) communicated with the main pipe (41), the flushing member inlet (411) is arranged on one side of the main pipe (41) away from the branch pipes (42), one end of the branch pipe (42) away from the main pipe (41) is arranged in a closed manner, and the flushing member outlet (421) is arranged on the side wall of the branch pipe (42).

4. An MBR membrane online cleaning device according to any one of claims 1-3, wherein the gas-liquid mixing tank (30) is further provided with a medicament addition port (34) communicating with the mixing chamber.

5. The MBR membrane online cleaning device according to claim 4, wherein a ph value detection device (60) is arranged on the liquid inlet (31) side of the gas-liquid mixing tank (30).

6. An MBR membrane in-line cleaning device according to any one of claims 1-3, further comprising a water pump (70), the water pump (70) being mounted on the side of the liquid inlet (31) for feeding the liquid in the membrane tank (10) into the mixing chamber and then ejecting the gas-liquid mixture in the mixing chamber from the flushing member outlet (421).

7. The MBR membrane online cleaning device according to claim 6, wherein the inlet side of the water pump (70) is provided with a filter (80).

8. An MBR membrane online cleaning device according to any one of claims 1-3, wherein the gas-liquid mixing tank (30) is further provided with an exhaust port (35) communicated with the mixing chamber, the exhaust port (35) is located at the upper part of the mixing chamber, and the MBR membrane online cleaning device further comprises an exhaust valve (90) for controlling the opening and closing of the exhaust port (35).

9. A sewage treatment system, comprising:

the membrane pool (10) is provided with a storage cavity and a membrane pool liquid outlet (11) communicated with the storage cavity;

MBR membranes (20), wherein a plurality of MBR membranes (20) are arranged, and a plurality of MBR membranes (20) are arranged at intervals;

The MBR membrane online cleaning device according to any one of claims 1-8, wherein the liquid inlet (31) is communicated with the membrane tank liquid outlet (11), and one end of the flushing member (40) provided with a flushing member outlet (421) is positioned between two adjacent MBR membranes (20).

10. A sewage treatment system according to claim 9, wherein the membrane tank outlet (11) is located in an upper portion of the storage chamber.