JP2585879Y2 - Membrane separation device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a membrane separation device, and more particularly to a membrane separation device useful for removing suspended matter contained in water such as river water and waste water.

[0002]

2. Description of the Related Art Conventionally, as a membrane separation apparatus for filtering a suspended matter in water, there is one having a flow shown in FIG. That is, the water to be treated, which is supplied into the treated water tank 30 through the treated water introduction pipe 41, is supplied to the membrane module 32 by the pump 31.
Where the suspension is separated by filtration membrane 33 into filtered water from which the suspension has been filtered and concentrated water in which the concentration of the suspension has been increased (in the case of cross flow). The filtered water passes through a filtered water pipe 34, is fed into the backwash water storage tank 35 from the bottom, moves in the tank 35, and is taken out through a take-out pipe 36 at an upper portion thereof, and is provided for a desired use or the like. Things.

[0003] Reference numeral 37 denotes a circulation line through which the concentrated water is returned to the to-be-treated water tank 30. In addition, such a circulation is continued and the treated water tank 3
If the settled sludge consisting of the concentrated suspended matter accumulates at the bottom of the tank 0, the sludge is appropriately drawn out of the tank 30.

[0004] In the above-mentioned apparatus, since the deposition of suspended matter and the like occurs on the membrane surface of the filtration membrane 33 due to the continuous filtration and the filtration performance is deteriorated, the backwashing operation is appropriately performed to remove the deposits on the filtration membrane. Has been done in the past. That is, when the compressed air is sent from the air chamber 38 to the backwash water storage tank 35, the backwash water in the storage tank 35 is caused to flow in the reverse direction to the direction in which the water to be treated is filtered into the module 32 through the pipe 34, The deposits on the membrane surface of the filtration membrane 33 are washed away.

Further, in order to efficiently remove deposits on the membrane surface of the filtration membrane 33, for example, after the above-mentioned backwashing is repeated several times, a backwashing operation is performed using a chemical solution such as an aqueous solution of hydrochloric acid or an aqueous solution of sodium hydroxide. Performing chemical cleaning (hereinafter referred to as chemical cleaning) is also often performed. In FIG. 2, reference numeral 39 denotes a cleaning solution storage tank, in which the solution inside is sent to the membrane module 32 through the solution injection line 40, and the filtration membrane 33 is washed.

However, in the above-mentioned conventional method for cleaning a filtration membrane, it is necessary to provide a backwash water storage tank 35, a cleaning chemical storage tank 39, and ancillary equipment for the backwash operation, and these equipment costs are high. And a large installation area is required. Further, when a chemical washing operation is performed, after this device is operated for a long time, the chemical solution used for the chemical washing is completely washed out from the module 32, the filtered water pipe 34, the backwash water storage tank 35, the discharge pipe 36, and the like. If it is not possible to start water sampling without using the conventional apparatus, as shown in FIG. 2, the filtered water is always taken out through the backwash water storage tank 35. The washed out chemical solution is once introduced into the backwash water storage tank 35. For this reason, the inside of the backwash water storage tank 35 having a considerable capacity is contaminated with the cleaning solution, and there is a problem that a long operation was conventionally required to remove the contaminated solution.

[0007]

In order to solve the above-mentioned problems, the inventors of the present invention provided a means for supplying a cleaning solution to the backwash water storage tank, and supplied the cleaning solution to the backwash water storage tank during washing. By doing so, we tried to share the backwash water storage tank with the cleaning chemical storage tank. However, also in this case, it was not possible to solve the problem that it takes a long time to wash out the chemical solution after the chemical washing.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem. It is an object of the present invention to provide a membrane separation apparatus which reduces equipment costs and equipment area, and shortens the time required for washing out a cleaning solution. It is in.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a membrane module for filtering water to be treated supplied to an inlet of a membrane module and removing filtered water from an outlet of the membrane module, and a cleaning chemical solution. A backwash water storage tank provided with a supply means, a wash water supply means for supplying backwash water or a cleaning chemical solution in the backwash water storage tank to an outlet of the membrane module, and the membrane module outlet and the backwash water storage tank. A filtered water pipe to be connected,
A filtered water discharge pipe branched from the filtered water pipe, and operating a branch valve provided on the filtered water pipe.
The first filtered water that has passed through the filtration membrane after
The present invention proposes a membrane separation device having a structure in which the film is transferred to a backwash water storage tank .

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a flow chart showing one embodiment of the membrane separation apparatus of the present invention. In the drawing, reference numeral 1 denotes an inlet pipe for treated water. Water 2 to be treated, such as river water, to be subjected to membrane filtration is supplied to a water treatment tank 3 through the introduction pipe 1. The treated water 2
Then, via a supply pipe 5 with a pump 4 interposed,
It is sent to the inlet 7 of the membrane module 6. The membrane module 6 is of a cross flow type, and contains therein, for example, a number of hollow filtration membranes 8. The water 2 to be treated sent to the inlet 7 of the module 6 is separated by the filtration membrane 8 into filtered water that has passed through the membrane to remove solids and the like, and concentrated water having an increased amount of solids. Is done.
The concentrated water is returned to the water tank 3 through the circulation line 9.

An outlet 10 of the module 6 is connected to one end of a filtered water pipe 11 at the outlet.
The other end is a circulation unit 1 provided at the bottom 13 of the backwash water storage tank 12.
4. Reference numeral 15 denotes an air chamber as cleaning water supply means for supplying backwash water or cleaning chemicals in the backwash water storage tank 12 to the outlet section 10 of the membrane module 6, thereby compressing air into the backwash water storage tank. 12 to
The backwash water or the like inside is suppressed and the backwash water or the like is pumped into the membrane module 6 from the outlet 10 of the membrane module 6. As the washing water supply means, for example, a water supply pump or the like can be used. Reference numeral 16 denotes a cleaning chemical liquid supply means for supplying the cleaning chemical liquid to the backwash water storage tank 12 via the chemical liquid injection line 17.

The filtered water pipe 11 is provided with a three-way valve 18. The valve 18 has a filtered water outlet pipe 19.
Are connected at one end.

Next, the operation of the membrane separation apparatus having the above configuration will be described.

During normal operation of the membrane separation device (during removal of filtered water), the filtered water filtered by the membrane module 6 as described above is discharged from the outlet 10 of the module 6, a filtered water pipe 11, a valve 18, and a removal pipe. The filtered water is sequentially taken out and taken out to the outside, and is provided for a desired use. In this case, the filtered water is not supplied to the backwash water storage tank 12. As the above operation is continued, solids are deposited on the filtration membrane surface of the membrane module 6 and the filtration performance is reduced. In this case, as described below, normal backwashing with backwash water, Alternatively, the membrane is washed by performing a chemical washing with a chemical solution.

That is, first, when performing the chemical washing, a predetermined amount of the concentrated chemical is supplied to the backwashing water storage tank 12 by the chemical washing supply means 16, and the filtered water previously stored in the tank 12 is described later. To prepare a chemical solution for washing at a desired concentration.

Next, the pump 4 is stopped, the valve 18 is operated to cut off the flow path of the take-out pipe 19, and the inside of the module 6 is communicated with the inside of the backwash water storage tank 12. Next, by supplying compressed air to the backwash water storage tank 12 by the air chamber 15, the chemical solution 20 in the tank 12 is supplied to the circulation unit 14,
The water is sent into the module 6 through the filtered water pipe 11, the valve 18, the filtered water pipe 11, and the outlet 10 in order, and
Passes in the direction opposite to the filtration direction of the water to be treated.
As a result, the washing operation using the chemical solution 20 of the filtration membrane 8 is performed, and the washing wastewater containing solids separated from the filtration membrane 8 is discharged out of the system via the discharge pipe 21 branched from the circulation line 9. After the chemical cleaning, the operation of the air chamber 15 is stopped, and the pump 4 is operated to supply the water 2 in the water tank 3 to the membrane module 6 and filter the water 2 again. Start. By filtration of the water to be treated 2,
The first filtered water that has passed through the filtration membrane 8 flows in the reverse direction to the flow direction up to now, that is, the backwash water flows sequentially through the outlet 10, the filtered water pipe 11, the valve 18, the filtered water pipe 11, and the flow section 14. It is sent to the storage tank 12 and fills this tank 12. By this operation, the chemical solution adhering to the flow path of the module 6, the pipe 11, the valve 18, and the like is removed and transferred to the backwash water storage tank 12. In addition, even if the backwash water storage tank 12 is full, if the adhering agent solution is not sufficiently removed, the above operation is continued until the backwash water is sufficiently removed, and excess filtered water overflows from the backwash water storage tank 12. And discharge it out of the storage tank. Thereafter, the valve 18 is switched to connect the filtered water pipe 11 and the filtered water outlet pipe 19, and the connection to the backwash water storage tank 12 is shut off, so that filtered water containing no chemical liquid is removed from the outlet pipe 19. It can be taken out immediately. The above
First filtration that has passed through the filtration membrane 8 transferred into the backwash water tank 12
In the case of permeation, the isomorphous substance is deposited again on the filtration surface of the membrane module and filtered.
When performance decreases, for example, at regular intervals as described later
Do not use as backwash water or cleaning solution when performing backwash.
Can be.

When the backwashing operation with water is performed, the above operation may be performed without operating the chemical solution supply means 16.

In this embodiment, river water is used as the water to be treated. However, industrial water, sewage, industrial waste water and the like can also be used.

As the filtration membrane of the membrane module, those having a hollow fiber shape, a tubular shape, a flat membrane shape or the like are preferably used, and the filtration type is not particularly limited, such as general filtration, microfiltration, ultrafiltration and the like.

The chemical solution varies depending on the chemical species of the deposit, but is generally an inorganic acid such as hydrochloric acid or sulfuric acid, an alkali agent such as sodium hydroxide, an organic acid such as oxalic acid or tartaric acid, or a sodium hypochlorite. And the like are preferable.

It is preferable that the volume of the backwash water storage tank 12 be large enough to accommodate a sufficient amount of water for backwash.

In this embodiment, a cross-flow type membrane module is used. However, the present invention is not limited to this, and a total filtration type can be used. In this case, the circulation line 9 becomes unnecessary.

Further, a level meter or the like is provided in the backwash water storage tank 12. When the filtered water flows into the backwash water storage tank 12 and reaches a certain water level, the valve 18 is switched by the signal of the level meter, and the outlet pipe 1 is discharged.
An automatic control method may be used so that filtered water can be taken out from the filter 9. Further, a concentrated chemical solution for membrane cleaning is quantitatively put into the above-mentioned backwashing tank at regular time intervals, and the membrane is constantly washed with filtered water. The backwashing may be performed, and the backwashing may be performed at regular intervals.

[0025]

[Effect of the Invention] In the present invention, the flow path of the filtered water is divided into a flow path connected to the backwash water storage tank and a flow path to be directly fed to the next process without passing through the backwash water storage tank. since there is provided Te, filtered water containing many chemical after chemical washing, can be sent to the backwash water reservoir in a different flow path to the take-out flow path of the normal filtration water, therefore, necessary in the prior art The time required to wash out the chemical solution introduced into the backwash water storage tank was eliminated, greatly reducing the time required to wash out the chemical solution, and requiring the water used to wash out the chemical solution introduced into the conventional backwash water storage tank. Water recovery is also improved because it can be eliminated or significantly reduced. In addition, it permeates through the filtration membrane 8 transferred to the backwash water tank.
The first filtered water has solids again on the filtration surface of the membrane module.
Backwash water or chemicals for backwash when deposition and filterability are reduced
The backwash solution or chemical for backwash.
No need to prepare, and if necessary, quantitatively concentrate concentrated chemicals
Is sufficient and economical.

Furthermore, in the present invention, since the backwash water storage tank is configured to be used as a cleaning chemical liquid storage tank, equipment costs and installation area can be reduced as compared with the conventional case.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an embodiment of the present invention.

FIG. 2 is a flowchart showing a configuration of a conventional membrane separation device.

[Explanation of symbols]

 2 Water to be treated 3 Water tank to be treated 4 Pump 6 Membrane module 7 Inlet 10 Outlet 11 Filtration water pipe 12 Backwash water storage tank 15 Air chamber (wash water supply means) 16 Cleaning chemical liquid supply means 18 Valve 19 Extraction pipe

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B01D 65/02 C02F 1/44

Claims (1)

(57) [Scope of request for utility model registration] 1. A membrane module for filtering water to be treated supplied to an inlet of a membrane module and extracting filtered water from an outlet of the membrane module, a backwash water storage tank provided with a cleaning solution supply means, and a backwash water storage tank Cleaning water supply means for supplying a backwash water or a cleaning chemical solution in the membrane module outlet, a filtered water pipe connecting the membrane module outlet and the backwash water storage tank,
Wherein Ri Do from the filtrate filtered water takeout tube provided branched into pipes, Misao branch valve provided in the filtered water piping
The first filtered water that has passed through the filtration membrane after
A membrane separation device having a structure for transferring to a backwash water storage tank .