KR20110001685A - External-submersed membrane separating film device - Google Patents

Abstract

PURPOSE: An external-submersed separating film system is provided to supply air with one blower after supplying the air to an aeration tank, for reducing the entire installation cost of the system. CONSTITUTION: An external-submersed separating film system for dipping a separating film into a separate tank, is formed by successively installing a stabilization tank(10), an anoxic chamber(20), an anaerobic tank(30), an aeration tank(40), and a submersed separating film tank(50) connected to the separating film installed on the outside of the aeration tank using a pipeline or a partition wall. The system additionally includes a blower(70), an air washing line(L4), and a branch pipe(L6).

Description

EXTERNAL-SUBMERSED MEMBRANE SEPARATING FILM DEVICE}

The present invention relates to a membrane system in which the membrane is immersed in the outside of the aerobic tank, and more particularly, when the membrane is washed with air supplied through the air cleaning line, and the air is returned to the stabilization tank through the inner conveying line, The present invention relates to an external immersion membrane system that supplies some air to an exhalation tank so that air is supplied by a blower, thereby reducing the overall cost of equipment.

In general, the advanced sewage and wastewater treatment technology using a bioreactor for the advanced treatment of sewage and wastewater has been applied.

However, the conventional membrane reactor for sewage treatment has the following problems.

First, the conventional immersion membrane reactor (MBR: Membrane Bioreactor) can reclaim the activated sludge process from the membrane reactor by immersing the membrane in an existing aerobic tank, in which case the construction period becomes longer and the renovation is required. There are many limitations to renovation, such as the work being done on site.

Second, sewage has low organic matter / nitrogen ratio (C / N ratio) of influent and it is difficult to secure sufficient organic source for denitrification, so the nitrogen removal rate through membrane reactor is low.

Third, for simultaneous removal of nitrogen and phosphorus, the anaerobic tank for dephosphorization is generally located at the front end, and the anoxic tank for denitrification is located at the rear end. However, such a crude composition has a problem of low nitrogen removal rate due to the inability to secure sufficient organic sources in the rear anoxic tank due to substrate competition generated during denitrification and dephosphorization.

Fourth, the separation tank has high energy cost due to the excessive supply of air volume for cleaning the membrane, and the dissolved oxygen (DO) concentration in the inner conveying line returned from the separation tank to the anaerobic tank and the anoxic tank increases the dephosphorization and denitrification microorganisms. Will receive.

Fifth, it is advantageous to effectively increase the dissolved oxygen concentration in the aerobic tank by supplying fine air for organic matter oxidation in the sewage and wastewater altitude treatment process in which organic membranes are immersed in the aerobic tank to treat organic matter, while the membrane provides air having coarse air bubbles. It is effective to wash the separation membrane. Therefore, in the advanced sewage treatment process using the conventional immersion membrane, there is a conflict between the air size required to increase the dissolved oxygen concentration in the aerobic tank and the air size required to clean the membrane.

Sixth, in the sewage treatment system by dipping the membrane, the washing air of the membrane is three to six times more than the air necessary to increase the dissolved oxygen concentration required to oxidize the organic matter, which causes a large amount of foam in the aerobic tank. There is a problem in that bubbles accumulate in the aerobic tank and scatter, or in a stabilization tank through the line conveyed from the aerobic tank.

Seventh, biological phosphorus removal requires the rapid extraction of over-phosphorus-induced microorganisms (ie, Solids Retention Time (SRT), and the membrane reaction tank is inevitably capable of maintaining a long microbial residence time, resulting in low phosphorus removal rates). .

Eighth, the suction pump of the membrane reaction tank process has a problem that the amount of the treated water is reduced due to the frequent occurrence of cavitation due to the inflow of bubbles during suction due to the contamination of the membrane due to the installation position is relatively high or long-term operation.

Accordingly, the present applicant, in view of the above problems, proposes a tank configuration to maximize the denitrification and dephosphorization in response to the low organic matter / nitrogen ratio of the sewage, and to prevent excessive width for cleaning the membrane, Measures to reduce the dissolved oxygen concentration of sludge returned to the anaerobic tank and anoxic tank from the membrane reaction tank, prevent cavitation upon aspiration, dualize supply of the air required for the aerobic tank and the membrane tank, and efficiently operate the cleaning air to the membrane immersed in the membrane tank. It has been registered (10-0836906) by the prior application (Patent Application No. 2007-0046767) to the external immersion biological membrane reaction tank provided to provide a method to effectively remove the bubbles generated in the membrane tank.

The 'applied membrane system with an apparatus that automatically removes bubbles generated by aeration during biological treatment process' registered and filed by the applicant of the present invention, while minimizing the time required to improve the existing activated sludge process by advanced treatment. Nitrogen removal rate is maximized, the membrane tank is installed separately from the aerobic tank, effectively reducing the air consumption for the membrane cleaning membrane, the cleaning air outflow prevention barriers are installed in the front and rear of the membrane module skids to minimize the loss of cleaning air, thereby reducing the air requirements effectively Therefore, there is an advantage that the denitrification efficiency is increased by reducing the power cost and the dissolved oxygen concentration of the internal transport line.

In addition, the bubble removing device is installed in the stabilization tank to effectively remove the bubbles generated during the over-aeration of the membrane tank, thereby improving the maintenance and environmental aspects of the system at the same time, and to ensure a stable throughput through the prevention of cavitation during suction There is this.

However, in the case of the 'immersion separator system with an apparatus for automatically removing bubbles generated by aeration during biological treatment,' despite the above advantages, there are the following problems.

That is, air necessary for decomposing organic matter by microorganisms in the separation membrane tank 50 and air necessary for removing and cleaning organic matter, sludge and microorganisms attached to the surface of the separation membrane 52 of the separation membrane tank 50 are supplied. The blower 70 and the blower 42 for increasing the dissolved oxygen concentration of the aerobic tank 40 to effectively remove the organic matters are provided separately, thereby causing an increase in the equipment cost.

The present invention has been made in view of the above problems, the external immersion membrane to reduce the overall equipment cost by supplying the air required for cleaning the separation membrane and aeration of the aerobic tank as a single air supply device, The purpose is to provide a system.

External immersion membrane system according to the present invention for achieving the above object, the immersion membrane reaction tank configured to immerse the membrane in a separate tank, stabilizing tank, anoxic tank, anaerobic tank, aerobic tank and the separation membrane outside the aerobic tank separately An external immersion membrane system having a immersion type separation membrane tank installed in order to be connected to the aerobic tank by a pipeline or a partition wall, comprising: a blower for blowing external air; An air cleaning line for supplying air blown by the blower to the separator to remove organic substances, sludge and microorganisms attached to the separator; Passing through the air cleaning line is characterized in that it comprises a branch pipe for supplying a part of the air to the aerobic tank, the air from which the organic matter, sludge and microorganisms of the membrane is removed.

In this case, the air cleaning line, it is preferable that the pulse aeration device consisting of an air receiver and an automatic pressure valve is installed so that the air supplied from the blower is intermittently supplied to the separation membrane.

In addition, a conveying line (L3) for returning the remaining air except for a part of the air supplied to the aerobic tank of the organic material, sludge and microorganisms of the separation membrane passing through the air cleaning line to the stabilization tank is provided, the conveying line It is preferable to install a dissolved gas reducing device.

Here, the dissolved gas reducing device may be composed of a vacuum decompression device for degassing and removing the dissolved oxygen by vacuum generation, and a sodium sulfite / cobalt ion injection device for further removal of dissolved oxygen remaining in an emergency.

As described above, according to the external immersion membrane system according to the present invention, the air required for cleaning the membrane and the aeration of the aerobic tank is supplied as a single air supply device, a very useful effect that the overall equipment cost is reduced There is.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a view for explaining an external immersion biological membrane reactor in which air for removing an aerobic organic matter and air injected for optimizing a membrane cleaning efficiency are united according to the present invention.

As shown, the external immersion membrane reaction tank according to the present invention is an external immersion membrane reaction tank configured to immerse the separator in a separate tank, the installation order of the stabilization tank (10), anoxic tank (20), anaerobic tank (30) It includes an external immersion membrane tank 50 is installed separately from the exhalation tank 40 and the outside of the exhalation tank 40, or connected through a conduit (L1) flowing in natural flow.

Then, the treated water flowing through the inlet pipe (L2) is configured to be distributed and supplied according to the inlet water conditions to the stabilization tank 10, an anaerobic tank 20 and the anaerobic tank 30.

In other words, when the inflow of organic matter / nitrogen ratio is low, the inflow can be increased to the anaerobic tank 20, and when the organic matter necessary for dephosphorization is insufficient, the inflow rate can be increased to the anaerobic tank 30. Depending on the denitrification and dephosphorization efficiency of the influent distribution, the injection rate may vary. Normally 0 to 20% into the stabilization tank 10, 60 to 80% into the anaerobic tank 20, the distribution flows in the range 0 to 20% into the anaerobic tank 30.

The stabilization tank 10 and the external immersion membrane tank 50 is connected to the conveying line (L3), the dissolved oxygen (DO: Dissolved Oxygen (DO) reduction device 60) is installed in the conveying line (L3), Supplying the air required to clean the separation membrane 52 installed in the external immersion membrane tank 50 and the air supplied to remove the organic matter by effectively increasing the dissolved oxygen concentration of the aerobic tank 40 to supply at the same time An air supply device 90 is provided.

The air supply device 90 includes a blower 70 for blowing outside air, an air cleaning line L4 for supplying air blown by the blower 70 to the separator 52, and the air cleaning line L4. And a part of the air that has been cleaned of the pulse aeration device and the separation membrane 52, which are installed in the air receiver 72 and the automatic pressure valves 74 and 75, are supplied to the aeration tank 40. The branch pipe L6 is included.

That is, the air after cleaning the separation membrane 52 is conveyed to the stabilization tank 10 through the inner conveying line (L3), at this time, some of the conveyed air, the separation membrane tank 50 and the aerobic tank 40 It is supplied to the aerobic tank 50 through the branch pipe (L6) connected between, the air supplied to the aerobic tank 50 to increase the dissolved oxygen concentration in the aerobic tank to facilitate the organic material treatment.

Therefore, the air supplied by the blower 70 is supplied to the separation membrane 52 through the air cleaning line L4 to remove organic substances, sludge and microorganisms attached to the surface of the separation membrane, and then the internal transfer line L3. Is returned to the stabilization tank (10), at which time some of the conveyed air is supplied to the aerobic tank (50) through the branch pipe (L6) to effectively increase the dissolved oxygen concentration to remove the organic matter.

In the separation membrane 52 installed in the external immersion membrane tank 50, 1 to 30 modules are mounted on one skid according to the processing capacity, and a large size of air bubbles for effectively cleaning the separation membrane 52 are blowers. 70 is supplied through the air cleaning line (L4), and the flow of the fluid in the membrane tank 50 by intermittent air injection between the upper and lower parts of the separator by a pulse aeration device consisting of automatic pressure valves (74, 75) It is configured to effectively guide the cleaning of the separation membrane, and also the air flow from the lower portion by the automatic valve 75 to the fluid flow in the separation tank 50 rises vertically, and the front and rear left and right of the separation membrane can not be cleaned It consists of a cleaning air leakage preventing partition 51 for preventing the loss.

The stabilization tank 10 and the external immersion membrane tank 50 is connected to the conveying line (L3), the bubbles generated by the over-aerated air for cleaning the separation membrane tank through the conveying line (L3) stabilization tank (10) It flows into) and accumulates. Bubbles accumulated in the stabilization tank are viscous and do not liquefy during their stay, causing them to scatter out of the system and contaminate the sewage treatment site. Therefore, by installing the apparatus (100, 110, 120) for automatically removing the bubbles accumulated in the stabilization tank 10, the foam is liquefied and returned to the stabilization tank 10 or discharged to the outside of the system for processing.

Bubbles removed through the apparatus 100, 110, 120 to automatically remove the foam contains a high concentration of microorganisms, so when the liquefied bubbles are continuously discharged to the outside of the system to lower the concentration of microorganisms in the system to reduce the organic matter removal performance of the system liquefaction The liquefied foam is returned to the stabilization tank or discharged out of the system at a proper cycle through the bubble conveyance and discharge pipe (L10). Here, the appropriate liquefied bubble discharge cycle has the advantage of minimizing the sludge discharge in the aerobic tank 40 by favoring the appropriate microbial concentration in the system.

Dissolved oxygen reduction device 60 is installed in the inner conveying line (L3) is a vacuum decompression device 62 for removing and removing dissolved oxygen in the vacuum generation, and sodium sulfite / cobalt for further removal of dissolved oxygen remaining in an emergency The ion implantation device 64 is comprised.

An air separator 82 is installed at the front of the suction pump 80 installed in the discharge line L5 to prevent the phenomenon of cavitation by discharging air when a certain level of steam cavities are generated.

In addition, the aerobic tank 40 is further provided with a chemical injection pump 44 to add Alum (alum: 明礬) so that the phosphorus removal by the chemical injection in parallel. The drug injection pump 44 is a conventional fixed-quantity drug supply pump configured to inject a predetermined amount of Alum into the aerobic tank 40 by the operation of the supply pump, so detailed description thereof will be omitted. In addition, although not shown in FIG. 1, sludge generated due to decomposition of organic matter is generally removed by drawing in the separation membrane tank 50, but in this process, since the sludge particles are fine due to overaeration of the separation membrane tank 50, it is difficult to separate and remove the sludge. The sludge particles are drawn and removed in the aeration tank 40 where the sludge particles can grow larger by Alum injected in an emergency.

The anoxic tank 20 performs a process of converting nitrate nitrogen into nitrogen gas using an organic material, the anaerobic tank 30 performs a process of releasing phosphorus in water using an organic material, the aerobic tank 40 is The organic material is oxidized and nitrified to a section in which microorganisms grow by using air (oxygen), and the external immersion type separation membrane tank 50 performs a process of filtering the liquid to be treated.

Using the external immersion membrane reactor of the configuration described above, the wastewater treatment step is described for each configuration as follows.

External-Submersed Membrane Bioreactor

Existing submerged membrane reactors are internally-submersed to immerse the membranes in aerobic tanks, so the tanks need to be emptied for renovation and all work must be done on site. However, in the case of the external immersion membrane reactor in the form of a module in FIG. 1 according to the present invention, the separator 52 is immersed in a separate membrane tank 50 outside the aerobic tank 40, that is, in an external immersion method By doing so, it is possible to easily renovate an existing treatment plant by simply installing the finished product in a separate factory and producing the finished product in a separate factory, without causing the downtime of the treatment plant caused by emptying the entire tank.

In addition, the membrane is concentrated so that only the membrane module of the external immersion membrane tank 50 can enter, so that the membrane 52 can be effectively cleaned, and when the chemical cleaning of the membrane 52 is carried out, the membrane 52 is external to the tank. It can be washed in the same reaction tank without being washed out in a separate washing tank, and since the entire aeration tank is not used when cleaning the separation membrane 52, stable processing can be performed in the remaining reaction tank except the external immersion separation membrane tank 50 even during cleaning. Therefore no process interruption occurs.

When the membrane 52 is cleaned, the sludge of the aerobic tank 40 is returned to the anaerobic tank 20 through the bypass line L7 instead of flowing into the external immersion membrane tank 50. , The denitrification process is configured to be performed without a problem, and the cleaning is performed in the external immersion type separation membrane tank 50.

Primary wastewater treated in the aerobic tank is introduced into the natural flow by the pipeline (L1) to the external immersion membrane tank 50, or when the membrane tank 50 is installed on the top of the aerobic tank (40) installed internal return pump ( 90 is installed on the pipe line L1 to pressurize and inlet, and the inner conveyance from the external immersion type separation membrane tank 50 to the stabilization tank 10 is configured to be possible by natural flow along the conveying line L3. When the separation membrane tank 50 is installed on the top of the aerobic tank 40, the external immersion membrane tank 50 is installed at a position higher than the stabilization tank 10 in order to make the flow by the natural flow.

2. Process composition

Characteristic of the process configuration of the present invention is the stabilization tank 10 is located first, and then consists of an anaerobic tank 20, anaerobic tank 30, aerobic tank 40, external immersion separation membrane tank (50). The influent is configured to be distributed and supplied to the stabilization tank (10), anoxic tank (20) and anaerobic tank (30), distribution injection into the anaerobic tank (30) when dephosphorization efficiency decreases due to lack of organic matter after deoxygenation tank (20) (0) 30%). Due to the high concentration of dissolved oxygen in the conveying line (L3) due to the aeration of the externally immersed separation tank (50) for cleaning the separation membrane (52), the activity of the denitrification bacteria is inhibited, in the present invention by the installation of the stabilization tank (10) This problem is solved by reducing the dissolved oxygen of the internal conveying line (L3). The order of the composition is very important for the simultaneous removal of nitrogen, phosphorus stabilization tank 10, anoxic tank 20, anaerobic tank 30, aerobic tank 40, external immersion separation membrane tank (as mentioned above) 50). The anaerobic tank 20 was placed prior to the anaerobic tank 30 so that the organic material could be utilized for nitrogen removal preferentially, and at the same time, it was possible to exclude the influence of nitrate nitrogen when dephosphorization in the anaerobic tank 30. The internal transport was returned to the stabilization tank 10 rather than the anoxic tank 20 to remove residual dissolved oxygen in advance, thereby minimizing the effects of dissolved oxygen in the oxygen-free tank 20. Stabilization tank 10 is designed to reduce the dissolved oxygen in the return water serves as a selector for the main purpose or to suppress the fungal bacteria.

3. Measures to reduce air volume for membrane cleaning: Air receiver + pulse aeration, dual distribution of aerobic tank and membrane tank, inflow of cleaning air into upper and lower part of membrane module

In order to reduce the amount of air required to clean the separation membrane 52, an air receiver 72 is installed in the air cleaning line L4 to supply air to the separation membrane 52 intermittently by the blower 70. (Pulse Aeration) method is applied. In other words, the automatic opening and closing of the automatic pressure valve (74, 75) is open to the intersection of the upper and lower air intermittently reduces the overall air consumption compared to the continuous air injection method, reducing the energy cost, the large air bubbles are separated by the pulse air method (52) By cleaning the surface, the cleaning effect is also superior to that of the existing fine bubble method. In addition, the air required for biological treatment in the aerobic tank 40 is also supplied separately from the air supplied by the blower 70 to the air having a relatively high oxygen content, thereby separately supplying the air supplied to the existing cleaning and biological treatment. Compared to the case, the equipment cost is reduced.

4. Measures to reduce dissolved oxygen in internal conveying line

In order to prevent the denitrification rate of the anoxic tank 20 generated by the high dissolved oxygen of the internal transport line L3, the dissolved oxygen reduction device 60 is mounted on the transport line L3.

The dissolved oxygen reduction device 60 is a vacuum decompression device 62 for degassing and removing dissolved oxygen by generating a vacuum of -1 to -5 atmospheres, and sodium sulfite / cobalt ion for further removal of dissolved oxygen remaining in an emergency. It is composed of an injection device (64). At this time, cobalt ions are injected at 0.01 ~ 0.1mg / L to perform a catalytic role to enable rapid dissolved oxygen removal reaction. The sodium sulfite / cobalt ion injector 64 may be used because a conventional feed pump configured to perform chemical injection by operation of the feed pump may be omitted.

5. Biological and Chemical Removal

In the present invention, the aerobic tank 40 is installed in the emergency injection medicine preparation facility is removed phosphorus by the simultaneous action of biological and chemical removal. In other words, it is inevitable to maintain long microbial retention time due to the characteristics of the membrane reaction tank, and the removal rate of phosphorus is low. Since the process is configured to prioritize, the insufficient phosphorus removal rate is compensated by the chemical injection pump 44 which quantitatively adds Alum [(Al ₂ SO ₄ ) ₃ .18H ₂ O]. The use of organic materials should give priority to denitrification rather than dephosphorization, as the input of Alum for phosphorus removal is advantageous in terms of cost, constructability and ease of maintenance rather than supplying external carbon sources for denitrification. However, in order to increase phosphorus removal rate, phosphorus removal by chemical injection is combined.

6. Prevention of cavitation of pump during suction

The suction pump 80 installed in the discharge line L5 of the membrane reaction tank process has a high installation location due to site conditions, and thus cavitation frequently occurs due to bubble inflow during suction, or the contamination of the membrane increases. There is a problem in that the amount of treated water produced is reduced due to the occurrence of cavitation due to air inflow during suction. In order to solve such a problem, in the present invention, an air separator 82 is installed in the front of the suction pump 80 installed in the discharge line L5 to discharge the air when a certain level of steam cavities are generated. prevent.

The air removing device 82 is provided with a check window 83 and a liquid column 84 for checking an internal state, and an automatic valve 86 and a vacuum pump 87 interlocked with the level switch 85 are installed. . The vacuum pump 87 is installed to be interlocked by the level switch 85 and the suction pump 80, the vacuum pump 87 is operated only between the low and high water level switch 85, in this case the suction pump (80) ) Is always in operation. The level difference between the level of the air removing device 82, that is, the difference between the high level and the low level is 20 to 40 cm, and the flow rate inside the air removing device 82 is maintained at 0.2 to 0.5 m / s. As the air generated by the cavitation occurs, the water level of the air removing device 82 is lowered. When the water level drops to the set low water level, the automatic valve 86 is opened and the vacuum pump 87 is operated to draw air into the air discharge pipe L8. Forced discharge to the outside through) and stops automatically when the high water level is reached. At this time, the vacuum pump 87 is to be installed in the highest pipe position between the separation membrane 52 and the suction pump 80, the suction pump 80 must be installed below the air removal device 82, the phenomenon Prevent occurrence. The outlet position of the air removal device 82 is configured to be lower than the inlet point.

7. Effective removal of viscous bubbles caused by aeration

The separation membrane 52 installed in the separation membrane tank 50 has poor treatment performance due to adhesion of organic substances, sludge and microorganisms to the membrane surface in the process of sucking the treated water. In order to prevent this, air is supplied to the separator surface using a blower 70 to desorb the pollutant attached to the membrane surface. The air required for the desorption of the pollutant is three to six times more than the air requirement for the decomposition of organic matter by microorganisms in the aerobic and separation membrane tanks. It accumulates in 50 or flows into a stabilization tank through the conveyance lie L3. Since the stabilization tank 10 is smaller in size than the separation membrane tank 50, when bubbles are introduced, the bubble level rises quickly and flows out of the stabilization tank 10, or when the treatment plant is in an external exposure form, the whole treatment plant is caused by wind. There is a problem that is scattered. Therefore, in the present invention, in order to solve this problem, by installing the device (100, 110, 120) to remove the bubbles in the stabilization tank 10, when the foam above a certain level occurs by aspiration to liquefy and discharged out of the system or stabilization tank (10) A system for returning to the system was configured. The bubble removing system is composed of a bubble removing device 100, bubble suction pump 110, bubble detection device 12 and the conduit (L9, L10), the bubble detection device 12 is a stabilization tank (10) Detects this when bubbles above a certain level are detected, and automatically operates the bubble suction pump 110 to suck it into the bubble suction pipe line L9, and the sucked bubbles are liquefied in the bubble removing device 100, and then the bubble discharge pipe path ( Discharge out of the system through the L10 or back to the stabilization tank (10).

The external immersion biological membrane reaction tank having the above configuration minimizes the time required to improve the existing activated sludge process with high treatment while maximizing the nitrogen removal rate, and separates the membrane tank from the aeration tank to install the air consumption for the membrane cleaning. It can effectively reduce the efficiency of air consumption by minimizing the loss of cleaning air by installing cleaning air leakage preventing partitions before and after the membrane module skid before and after the skid, and can improve the denitrification efficiency by reducing the power cost and reducing the dissolved oxygen concentration of the inner conveying line. In addition, by installing a bubble removing device in the stabilization tank to effectively remove the bubbles generated during the over-aeration of the membrane tank to improve the maintenance and environmental aspects of the system at the same time, it is possible to secure a stable throughput through the prevention of cavitation during suction.

8. Aeration of the aerobic tank

After the separation membrane 52 has been cleaned, the air is conveyed to the stabilization tank 10 through the transfer line L3 in the state in which dissolved oxygen is removed by the dissolved oxygen reducing device 60.

At this time, some of the air to be conveyed, is supplied to the aerobic tank 40 through the branch pipe (L6), the air supplied to the aerobic tank 40 through the branch pipe (L6) is dissolved oxygen is not removed state It has a state containing sufficient dissolved oxygen.

Therefore, the air containing dissolved oxygen is supplied to the aerobic tank 40 as described above, so that the dissolved oxygen concentration is increased in the aerobic tank 40, so that organic matter treatment is easily performed.

1 is a schematic view showing the configuration of an external immersion membrane system according to the present invention.

<Explanation of symbols on main parts of the drawings>

10: stabilization tank 20: anoxic tank

30: anaerobic tank 40: aerobic tank

50: separation membrane tank 52: separation membrane

60: dissolved gas reducing device 62: vacuum pressure reducing device

64: sodium sulfite / cobalt ion injector

70: blower 72: air receiver

74,75: Automatic pressure valve L3: Internal conveying line

L4: Air cleaning line L6: Branch pipe

Claims (4)

An immersion type membrane reaction tank configured to immerse the membrane in a separate tank, and an external immersion tank in which stabilization tanks, anoxic tanks, anaerobic tanks, aerobic tanks, and immersion type membrane tanks in which the membranes are separately installed in the outside of the aerobic tanks and connected to the aerobic tanks by pipelines or partition walls are sequentially installed. In the knowledge separator system, A blower for blowing outside air; An air cleaning line for supplying air blown by the blower to the separator to remove organic substances, sludge and microorganisms attached to the separator; An external immersion membrane system, characterized in that it comprises a branch pipe for supplying a part of the air to the aeration tank of the air from the organic matter, sludge and microorganisms of the separation membrane passing through the air cleaning line. The method of claim 1, The air cleaning line, the external immersion membrane system, characterized in that a pulse aeration device consisting of an air receiver and an automatic pressure valve is installed so that the air supplied from the blower is intermittently supplied to the separator. The method of claim 1, A conveying line (L3) is provided for returning the remaining air except for a part of the air supplied to the aerobic tank to the stabilization tank of the air from which the organic matter, sludge and microorganisms of the separator are removed by passing through the air cleaning line, and the conveying line has a dissolved gas. External immersion membrane system, characterized in that the reduction device is installed. The method of claim 3, wherein The dissolved gas reducing device is an external immersion membrane system comprising a vacuum decompression device for degassing and removing dissolved oxygen by vacuum generation, and a sodium sulfite / cobalt ion injection device for further removal of dissolved oxygen remaining in an emergency.

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