JPH1190189A - Method for cleaning membrane with liquid chemical - Google Patents

Abstract

PROBLEM TO BE SOLVED: To completely clean the inside of a membrane by providing a diffuser pipe on the bottom side of a tank and the membrane above the diffuser pipe, connecting a pipeline having a pump to the membrane, allowing the bubbles injected from the diffuser pipe to hit the membrane, sucking a liq. chemical by the pump through the inside of the membrane and circulating the sucked chemical in the tank. SOLUTION: A tank 1 is filled with a liq. chemical 8, and a membrane 2 is dipped in the chemical 8 and arranged in the tank. A diffuser pipe 3 is provided on the bottom side of the tank 1, the diffuser pipe 3 is connected to a blower 4, and bubbles are injected from the diffuser pipe 3 and hit against the membrane 2. Further, a pipeline 5 is connected to the upper end of the membrane 2, a differential pressure gage 6 and a pump 7 are furnished to the pipeline 5, and the pipeline on the downstream side of the pump 7 is extended toward the inside of the tank 1. When the membrane 2 is cleaned, the blower is operated to inject the bubbles from the diffuser pipe 3 toward the membrane 2, the pump 7 is driven to suck the chemical 8 in the tank 5 through the membrane 2, the chemical 8 is recirculated into the tank 1, and the membrane 2 is cleaned by the chemical 8 passing through the inside of the membrane 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning method for cleaning a film with a chemical.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 2 to 5, a membrane 52 composed of a hollow fiber membrane or a flat membrane is disposed in a treatment tank 51, and is disposed in the treatment tank 51. Is filled with sludge 54, a pump 53 is connected to the membrane 52,
It is configured so that domestic sludge can be purified by activated sludge in the treatment tank 51. The membrane 52 needs to be washed, for example, about twice a year to eliminate clogging of the membrane 52. Then, the sludge 54 in the processing tank 51 is discharged to fill the processing tank 51 with a chemical solution 55 as shown in FIG.
The film 52 is washed with the chemical solution 55 by leaving the film 52 immersed in the chemical solution 55, neutralized as shown in FIG. 4 and then discharged, and treated again as shown in FIG. The sludge 54 is put into the tank 51, and the purification treatment by the activated sludge is continued through the membrane 52. As another method for cleaning the membrane, as shown in FIGS. A chemical liquid tank 56 filled with a chemical liquid 55 is prepared separately from the tank 51, and the film 52 in the processing tank 51 is lifted as shown in FIG. 7, and a separate chemical liquid tank as shown in FIG. The membrane 52 is immersed in the chemical solution 55 by being put in the chemical solution 55, and is left in this state. Thereafter, as shown in FIG.
2 and the processing tank 51 filled with the sludge 54 again.
In any of such conventional cleaning methods, since the film 52 is immersed in the chemical solution 55 and left to clean the film, the inside of the film 52 is completely cleaned. In some cases, it is difficult to perform cleaning with a chemical solution, and there is a problem that a portion that is not cleaned remains inside the film.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a method for cleaning a chemical solution of a film which can completely clean the inside of the film. The first gist is that a tank is filled with a chemical solution, an air diffuser is provided on the bottom side of the tank, and a film is disposed above the air diffuser in a state of being immersed in the chemical solution. A pipe having a pump is connected, and a chemical solution is sucked through the membrane by the pump while the foam ejected from the air diffuser is applied to the membrane, and the sucked chemical solution is circulated in the tank. The second gist is to provide a differential pressure gauge in the pipe and check the degree of cleaning of the membrane by the differential pressure gauge.

[0004]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a case in which a tank 1 is filled with a chemical solution 8 and the membrane 2 is disposed by being immersed in the chemical solution 8, and a diffuser 3 is provided at the bottom side of the tank 1. The trachea 3 is connected to an external blower 4, and is configured so that bubbles can be ejected upward from the diffuser 3 to apply bubbles to the membrane 2. Is connected to a pipe 5, a differential pressure gauge 6 is provided in the pipe 5, and a pump 7 is provided downstream thereof, and a pipe downstream of the pump 7 is piped into the tank 1. It has become. In addition,
The membrane 2 is formed as a module by a hollow fiber membrane or a flat membrane, and the chemical solution 8 is made of sodium hypochlorite or the like.

In such a configuration, while operating the blower 4 to eject bubbles from the air diffuser 3 toward the membrane 2, the pump 7 is operated to pass the chemical solution 8 through the membrane 2 into the pipe 5. The suctioned chemical solution 8 is returned to the tank 1 and circulated again. The chemical solution 8 is continuously circulated through the inside of the membrane 2, and bubbles from the air diffuser 3 are applied to the membrane 2. The membrane 2 can be completely washed with the chemical solution 8 passing through. In this case, since the clogging occurs in the membrane 2 at first, the scale display of the differential pressure gauge 6 is large. However, as the cleaning progresses, the clogging in the membrane 2 is removed, and the passage resistance in the membrane 2 is reduced, so that the scale display of the differential pressure gauge 6 becomes small. 2, the degree of cleaning can be recognized well, and the differential pressure Become completely state intima 2 is washed in a state where the scale of 6 reaches a predetermined value, is capable to complete the cleaning by stopping the operation of the pump 7 and the blower 4 in this state.

As described above, the membrane 2 can be surely washed while forcibly sucking the medicine into the membrane 2. After the washing is completed, the chemical solution 8 can be neutralized, and then the neutralized chemical solution can be discharged. After the discharge, the sludge 54 is put into the tank 1 and the purification treatment with activated sludge is performed. Can be done. Even if the tank 1 is a separate tank previously filled with the chemical solution 8, the tank 2
The inside can be completely washed, and the membrane 2 can be pulled out of the tank 1 after washing and returned to a predetermined processing tank.

[0007]

According to the present invention, a tank is filled with a chemical solution, an air diffuser is disposed at the bottom of the tank, and a film is disposed above the air diffuser in a state of being immersed in the chemical liquid. A pipe having a pump is connected to the membrane, and a chemical solution is sucked through the membrane by the pump while the foam ejected from the air diffuser is applied to the membrane, and the sucked chemical solution is circulated in the tank. Bubbles are blown out from the air diffuser to the membrane, and a chemical solution is forcibly circulated in the membrane by the pump, so that the inside of the membrane can be reliably washed with the bubbles and the chemical solution, and the cleaning power is strong. This has the effect that cleaning can be performed completely.

Further, since a differential pressure gauge is provided in the pipe and the degree of cleaning of the membrane is checked by the differential pressure gauge, the degree of cleaning of the membrane can be checked satisfactorily while looking at the differential pressure gauge. This has the effect that the completion time can be accurately grasped and the cleaning operation can be performed satisfactorily.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an apparatus for cleaning a film.

FIG. 2 is a schematic configuration diagram of a film provided in a conventional processing tank.

FIG. 3 is a schematic configuration diagram of a state in which sludge is extracted from the inside of a processing tank and the inside of the processing tank is filled with a chemical solution.

FIG. 4 is a schematic configuration diagram of a state in which a chemical solution is neutralized and discharged thereafter.

FIG. 5 is a schematic configuration diagram of a state in which sludge is again put into the processing tank.

FIG. 6 is a schematic configuration diagram in which another chemical solution tank is provided.

FIG. 7 is a schematic configuration diagram of a state in which a film in a processing tank is transferred into a separate chemical liquid tank.

FIG. 8 is a schematic configuration diagram of a state in which a film is left in a separate chemical solution tank.

FIG. 9 is a schematic configuration diagram of a state in which a film is transferred from a chemical solution tank to a processing tank again after cleaning.

[Explanation of symbols]

 1 tank 2 membrane 3 air diffuser 4 blower 5 pipe 6 differential pressure gauge 7 pump 8 chemical

Claims (2)

[Claims] A tank is filled with a chemical solution, an air diffuser is provided at the bottom side of the tank, a membrane is provided above the air diffuser in a state of being immersed in the chemical, and a pump is provided to the membrane. Connecting a pipe having a chemical solution to the membrane by sucking a chemical solution through the membrane by the pump while applying bubbles ejected from the air diffuser to the membrane, and circulating the sucked chemical solution into the tank. Cleaning method. 2. The method according to claim 1, wherein a differential pressure gauge is provided in the pipe, and the degree of cleaning of the film is checked by the differential pressure gauge.