JPH09122459A - Cleaning method for immersion type flat membrane and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method to clean a flat membrane separation apparatus at low cost by washing in water without requiring manual work at the time of cleaning and a large scale facility and to provide an apparatus for the method. SOLUTION: This apparatus is composed of a plurality of bag-like flat membranes 3 whose open ends are joined to a filtered fluid taking out pipe 4. In the apparatus, the closed end parts on the opposite to the open end parts are made movable along an almost arching guide rail 5 with the radius almost equal to the length of the flat membranes 3, the flat end parts of neighboring flat membranes 3 are joined mutually with a wire 6, one of the flat membranes 3 in both outsides is fixed and the closed part of the other is pulled up along the guide rail 5, so that respective flat membranes 3 are spread like a folding fan and in this state, the flat membranes 3 are cleaned by nozzles for cleaning which are brought down to the side faces of respective flat membranes 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a membrane cleaning method for a submerged flat membrane separation apparatus used in a closed water system such as a pond or a water tank, and the apparatus therefor.

[0002]

2. Description of the Related Art As a device for purifying raw water having suspended solids in a reservoir etc., there is an immersion type flat membrane separation device,
This is one in which flat membranes are bundled at one end, suspended, and sucked and filtered in the form of being suspended in water.

FIG. 4 shows such an immersion type flat membrane separation device. In FIG. 4, 1 is a pond, 2 is a flat membrane separation device,
Reference numeral 3 is a flat membrane, and 4 is a filtered fluid take-out tube. By a pump (not shown), water is sucked through the filtered fluid extraction pipe 4, and the raw water is filtered by the flat membrane 3 and then passes through the flat membrane.
The filtered water flows out from the filtered fluid take-out pipe 4.

Suction filtration of raw water is carried out by operating the pump for a certain period of time, but along with this, sludge is deposited on the flat membrane, and it is necessary to wash it. FIG. 5 is a diagram showing such a cleaning method. In the following figures, FIG.
The same parts as those described above are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIG. 5, in the case of washing, the flat sheet membrane separation device 2 is pulled up to the ground, a person turns the flat sheet membranes one by one, and washing is performed with a hose. After cleaning, attach it again in the original pond 1.

For such a method of cleaning on the ground,
There is a method disclosed in Japanese Patent Laid-Open No. 63-104608 as a method for cleaning the flat membrane separation device while it is installed in water.

FIG. 6 is a diagram showing such a method. In FIG. 6, 21 is a flat membrane set, 22 is a stopper, 23 is a cylindrical body, 24 is a shaft, and 25 is a lever. When the lever 25 is moved in the left-right direction, the shaft 24 slides in the left-right direction, and the cylindrical body 23 fixed to the shaft 24 swings the flat sheet set 21 left and right. As a result, the alternately superposed membrane sheets forming the membrane set 21 and the soft spacers are lightly slid to mechanically clean the membrane surface.

Further, as a method for cleaning while another flat membrane separation device is installed in water, there is a method disclosed in Japanese Patent Laid-Open No. 6-327949. FIG. 7 is a diagram showing such a method.

In FIG. 7, 31 is a flat permeable membrane cell, 32 is a flexible cleaning body, and 33 is an air ejection pipe. Air jet pipe
Air is jetted from the nozzle 33, and the mixed flow of the jetted air and raw water is raised between the flat permeable membrane cells 31. Due to this rising mixed flow, the flexible cleaning body 32 is swung and brought into contact with the membrane surface of the flat permeable membrane cell, and the deposits on the membrane surface are wiped off.

[0009]

However, the above-mentioned prior art has the following problems.

The method of pulling up the flat membrane separation device as shown in FIG. 5 to the ground to wash it requires a lifting device such as a crane, and since there is almost no space between the membranes, the membranes are manually pulled out. Must be washed by hand, which is time-consuming and unhygienic. Furthermore, a sludge recovery device after cleaning on the ground is required.

Further, the method of cleaning the flat membrane separation device shown in FIGS. 6 and 7 while it is installed in water does not require manpower for cleaning, but it requires a large amount of equipment and increases the manufacturing cost. There are drawbacks.

In view of the above problems, the present invention provides a method for cleaning a flat sheet membrane separator at low cost, which requires no manpower for cleaning, can be cleaned in water, and does not require large-scale equipment. With the goal.

[0013]

The above-mentioned problems can be solved by the following means.

In a method for cleaning a submerged flat membrane, which has a plurality of bag-shaped flat membranes whose open ends are connected to a filtration fluid take-out tube, the closed end of the flat membrane opposite to the open end is almost flat. It is possible to move along a guide rail that has an arc shape with a radius equal to the length, and connect the flat ends of adjacent flat membranes with a wire to fix one of the flat membranes on both outsides and the other. Each flat membrane is fan-shaped by pulling up one closed end of the flat rail along a guide rail, and in this state, the flat membrane is washed by a cleaning nozzle lowered on the side surface of each flat membrane. How to clean flat membranes.

According to the above means, by winding the wire with the winding machine, the end portion of the flat membrane to which the wire is connected is pulled along the guide rail. In this way, the ends of each flat film are pulled along the guide rails in order, so that each flat film easily opens into a fan shape, and the washing nozzle sufficiently flushes the wash water from the side surface of the flat film to the flat film surface. Can be ejected.

The above problems can be solved by the following means. In an immersion type flat membrane cleaning device having a plurality of bag-shaped flat membranes whose open ends are connected to a filtered fluid take-out pipe, a substantially arc-shaped guide rail having a radius substantially equal to the length of the flat membrane, and a flat membrane. Means for moving the closed ends of the flat membranes along the guide rails, a wire for connecting the closed ends of adjacent flat membranes, a means for fixing one of the flat membranes on both outer sides, and the other flat membrane. An immersion type flat membrane cleaning apparatus comprising a means for pulling up the closed end of the membrane along a guide rail and a cleaning nozzle vertically provided on both side surfaces of the flat membrane.

According to the above means, by winding the wire with the winding machine, the end portion of the flat membrane to which the wire is connected is pulled along the guide rail. In this way, the wire sequentially pulls the end of each flat film along the guide rail, so that each flat film easily opens in a fan shape, and the cleaning nozzle causes the cleaning water to sufficiently reach the flat film surface from the side surface of the flat film. It can be ejected for cleaning.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings.

1 to 3 are views showing an embodiment of the present invention, FIG. 1 is a view showing a state before cleaning, FIG. 2 is a view in which a flat film is opened in a fan shape by pulling a wire, FIG. 3 is a diagram in which cleaning is performed by the spray nozzle. 1 to 3, 5 is a guide rail, 6 is a wire, 7 is a winder,
Reference numeral 8 is a wire guide ring, 9 is a spray nozzle, and 10 is a washing water pipe.

As shown in FIG. 1, in the state before cleaning, each flat membrane is dented by its own weight, and the adjacent flat membranes hang down in the water in a closed state. In this state, the wire 6 hangs between the end portions of each flat film 3.
When the end of the wire 6 is wound up from the ground by the winder 7 from this state, the wire 6 is pulled through the guide ring 8 as shown in FIG. 2, and from the end of the flat film close to the winder side. The flat membrane 3 is opened along the guide rails 5. At this time, since the flat film 3 on the side opposite to the winder side is fixed in water, when the wire 6 is completely pulled, the flat film 3 is opened like a fan. In this state, as shown in FIG. 3, the spray nozzle 9 is lowered to the side surface of the flat film 3, the wash water is flown through the wash water pipe 10, and the wash water is jetted from the spray nozzle 9 to the surface of the flat film 3 to wash the flat film 3. To do.

Here, the guide rail may be rod-shaped or pipe-shaped. A chain may be used instead of the wire.

[0022]

As described above, according to the present invention, it is possible to wash a flat membrane separation device at low cost without requiring any manpower at the time of washing, it can be washed in water, and large equipment is not used. is there.

[Brief description of the drawings]

FIG. 1 is a diagram showing a state before cleaning according to an embodiment of the present invention.

FIG. 2 is a diagram in which a flat film is opened in a fan shape by pulling a wire in the embodiment of the present invention.

FIG. 3 is a diagram illustrating cleaning with a spray nozzle according to the embodiment of the present invention.

FIG. 4 is a view showing a conventional immersion type flat membrane separation device.

FIG. 5 is a diagram showing a cleaning method of a conventional immersion type flat membrane separation device.

FIG. 6 is a view showing a cleaning method of a conventional immersion type flat membrane separation device, which is different from FIG. 5.

FIG. 7 is a view showing a cleaning method of a conventional immersion type flat membrane separation device, which is different from FIGS. 5 to 6.

[Explanation of symbols]

 2 Flat membrane separation device 3 Flat membrane 4 Filtration fluid extraction pipe 5 Guide rail 6 Wire 7 Winder 9 Spray nozzle

Claims (2)

[Claims] 1. A method for cleaning a submerged flat membrane, which comprises a plurality of bag-shaped flat membranes each having an open end connected to a filtered fluid extraction tube, wherein a closed end portion of the flat membrane opposite to the open end is flattened. It is possible to move along a guide rail that has a substantially arcuate shape with a radius equal to the length of the membrane, and the flat ends of adjacent flat membranes are connected with a wire to fix one of the flat membranes on both outer sides. The flat membrane is fanned out by pulling up the other closed end along the guide rail, and in this state, the flat membrane is washed by the cleaning nozzle lowered to the side surface of each flat membrane. A method for cleaning an immersion flat membrane. 2. A cleaning device for a submerged flat membrane, the open end of which is composed of a plurality of bag-shaped flat membranes connected to a filtered fluid take-out pipe, and a substantially arc-shaped guide having a radius substantially equal to the length of the flat membranes. A rail, a means for moving the closed end of the flat membrane along the guide rail, a wire for connecting the closed ends of the adjacent flat membranes, and a means for fixing one of the flat membranes on both outer sides, An immersion type flat film cleaning apparatus comprising a means for pulling up the closed end of the other flat film along a guide rail, and a cleaning nozzle vertically provided on both side surfaces of the flat film.