WO2013035928A1 - Membrane filtering device without treated water storage and membrane washing method thereof - Google Patents

Abstract

The present invention relates to a membrane filtering device without treated water storage, which includes a plurality of filtering pumps for supplying supply water, a separation membrane filter for filtering the supply water by a separation membrane, a filtered water valve for regulating the discharge of filtered water, a backwashing valve for regulating the backwashing of the filtered water, a backwashing pump for distributing the backwashing water to a separation membrane filter, and a back washing water valve regulating the supply of the backwashing water. Accordingly, the present invention prevents recontamination of a separation membrane due to backwashing by improving space efficiency of the membrane filtering device and preventing contamination caused by remaining filtered water, and improves energy efficiency by reducing driving energy of an after treatment process.

Description

Membrane filtration device without treated water reservoir and membrane cleaning method

The present invention relates to a membrane filtration device without a treated water storage tank and a membrane washing method thereof, and more particularly, to a membrane filtration device which is treated in a membrane filtration process without a separate treated water storage tank for backwashing the membrane and storing the filtered water. The present invention relates to a membrane filtration apparatus without a treated water storage tank using a portion of the filtered water as a backwash water of a separation membrane, and a membrane washing method thereof.

In the membrane filtration process, which is a kind of water treatment, the separation membrane has pores formed on the surface thereof, thereby removing contaminants, thereby purifying water. In the membrane used in the membrane filtration process, contaminants excluded by the use of the membrane are deposited on the surface of the membrane or the pores are blocked, resulting in a decrease in filtration performance.

Therefore, in order to recover the filtration performance of the membrane reduced with use, backwashing is performed through a part of the filtrate periodically in the reverse direction of the filtration for several seconds to several tens of seconds after several minutes to several tens of minutes of operation.

Generally, in the membrane filtration process for water treatment, a certain amount of treated water is stored, and after filtering for a predetermined time, the filtered water is permeated in the reverse direction of the membrane filtration using a pump to remove and remove particulate matter deposited on the surface of the membrane or blocking pores. As a result, the filtration performance is restored.

However, in this case, a separate tank for storing the filtered water that has passed through the membrane is required, and as the processing capacity of the water treatment process increases, the volume of the treated water storage tank also increases to occupy space, and the driving pressure applied for the membrane filtration is treated. If the pressure is lost in the water storage tank to drive the post-treatment process, there is a problem that additional driving equipment is required.

In addition, there is a problem that the contamination of the separation membrane due to the backwash water contaminated during the backwash due to the contamination occurs in the treated water reservoir while the filtered water stays in the treated water reservoir.

The present invention has been made to solve the above-mentioned conventional problems, it is possible to remove the treated water storage tank in the membrane filtration device and thereby increase the space efficiency, which may occur due to the retention in the treated water storage tank of the filtered water It can prevent the backwash water pollution, prevent the recontamination of the membrane by the contaminated backwash water, improve the washing efficiency of the membrane, and do not need the driving equipment to supplement the driving pressure required for the aftertreatment process. It is an object of the present invention to provide a membrane filtration apparatus without a treated water storage tank and a membrane washing method thereof, which can increase the energy efficiency of a process.

The present invention for achieving the above object is a membrane filtration device for branching the supply water and filtering by the separation membrane, a plurality of filtration pumps for supplying each of the branched supply water; A plurality of separator filters for filtering the feed water pumped by the respective filtration pumps by a separator; A plurality of filtrate valves for opening and closing the discharge of the filtrate treated in each of the separator filters; A backwash valve installed downstream of the filtrate valve to open and close a counter flow of the filtrate so that a part of the filtered filtrate is returned to the separator filter to backwash the separator; A backwash pump pumping the backwash water flowed back by the backwash valve and branching to each of the separator filters; And a plurality of backwash water valves for opening and closing the supply of backwash water branched by the backwash pump, respectively.

A washing | cleaning agent injector which injects a washing | cleaning agent to the said backwashing water is connected between the said backwash pump and the said backwash valve of this invention. In the washing | cleaning agent injector of this invention, an input amount control valve is provided so that the input amount of the said washing | cleaning agent may be adjusted.

When backwashing the separation membrane of the present invention, the filtration pump connected to any one of the plurality of separation membrane filters is stopped, the filtration water valve is closed, the backwash water valve is opened, and the filtration pump connected to the remaining separation membrane filter is operated. Open the filtrate valve and close the backwash valve.

The membrane cleaning method of the membrane filter apparatus described above, the method comprising: stopping the filtration pump connected to any one of the plurality of membrane filters and closing the filtrate valve; Operating a filtration pump connected to the remainder of the plurality of separator filters and opening the filtrate valve; Opening the backwash valve and operating a backwash pump to backflow the filtrate of the membrane filter; And opening the backwash water valve connected to the separator filter in which the filtration pump is stopped and closing the remaining backwash valve.

The present invention is characterized in that it further comprises the step of introducing a cleaning agent to the backwash water between the backflow step of the filtered water and the opening step of the backwash water valve.

As described above, the present invention uses a portion of the filtered water filtered in the membrane filtration process as the backwash water of the separation membrane, thereby removing the treated water storage tank from the membrane filtration device, thereby providing an effect of increasing space efficiency. do.

In addition, it is possible to prevent contamination of the backwash water which may occur due to retention in the treated water storage tank of the filtered water and to prevent recontamination of the membrane by the contaminated backwash water, thereby improving the washing efficiency of the membrane. In addition, it is possible to improve the backwashing efficiency of the separator by adding a detergent to the backwashing water.

In addition, by using the driving pressure of the filtered water discharged from the membrane filtration process as the driving pressure of the post-treatment process, a driving device for supplementing the driving pressure necessary for driving the post-treatment process is unnecessary, which can increase the energy efficiency of the entire water treatment process. Provide effect.

1 is a block diagram showing a membrane filter apparatus without a treated water storage tank according to an embodiment of the present invention.

Figure 2 is a process state showing the filtration step of the membrane filter apparatus without the treated water storage tank according to an embodiment of the present invention.

3 is a process state diagram showing a backwashing process of a membrane filtration apparatus without a treated water storage tank according to one embodiment of the present invention;

Figure 4 is a comparison graph showing the driving pressure of the membrane filter device and the conventional membrane filter device according to an embodiment of the present invention.

5 is a flowchart illustrating a membrane cleaning method of a membrane filtration apparatus without a treated water storage tank according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

11, 12, 13: filtration pump 21, 22, 23: membrane filter

31, 32, 33: filtrate valve 41, 42, 43: backwash valve

50: backwash pump 60: backwash valve

70: detergent dispenser

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

1 is a block diagram showing a membrane filter apparatus without a treated water storage tank according to an embodiment of the present invention, Figure 2 is a process showing a filtration process of the membrane filter apparatus without a treated water storage tank according to an embodiment of the present invention 3 is a process state diagram showing a backwashing process of a membrane filter apparatus without a treated water storage tank according to an embodiment of the present invention, and FIG. 4 is a membrane filter apparatus and a conventional membrane according to an embodiment of the present invention. It is a comparative graph which shows the drive pressure of a filtration apparatus, and FIG. 5 is a flowchart which shows the membrane washing | cleaning method of the membrane filtration apparatus by one Example of this invention.

As shown in Fig. 1, the membrane filtration apparatus without the treated water storage tank of this embodiment includes filtration pumps 11, 12, 13, membrane filters 21, 22, 23, filtrate valves 31, 32, 33, and backwashing. It comprises a valve 60, backwash pump 50, backwash water valves (41, 42, 43) is a membrane filtration device for branching the feed water is filtered by the separation membrane.

Filtration pumps (11, 12, 13) are installed in the branched branch pipe to supply the feed water to each of the membrane filter (21, 22, 23) in the reservoir of the feed water, thus pumping the branched feed water respectively To each of the separator filters (21, 22, 23).

Filtration pumps (11, 12, 13) of the present embodiment. It consists of three filtration pumps of the first filtration pump 11, the second filtration pump 12, the third filtration pump 13, but of course it is also possible to consist of two or four or more filtration pumps.

Membrane filters 21, 22, 23 are installed in inlet pipes downstream of each filtration pumps 11, 12, 13, and feed water pumped by the respective filtration pumps 11, 12, 13 to the membrane. By filtering by means of filtering the contaminants contained in the feed water, the contaminant is discharged to the filtered filtered water downstream.

The membrane filter 21, 22, 23 of the present embodiment. Three membrane filters of the first membrane filter 21, the second membrane filter 22, and the third membrane filter 23, but of course two or four or more of the filtration pump is also possible.

Filtrate valves 31, 32, 33 are installed in the discharge pipe downstream of each membrane filter 21, 22, 23, and discharge pipe to control the discharge of the filtered water treated in each membrane filter 21, 22, 23. Will be opened and closed.

Filtrate valves 31, 32 and 33 of the present embodiment. The first filtrate valve 31, the second filtrate valve 32, and the third filtrate valve 33 are composed of three filtrate valves, but two or four or more filtrate valves may be possible.

The backwash valve 60 is installed in a backflow pipe connected to a conduit pipe joining the respective discharge pipes downstream of each of the filtrate valves 31, 32, and 33, and a portion of the filtrate water joined in the conduit pipe is connected to the backflow pipe. Through the reverse flow through each of the separator filters (21, 22, 23) to open and close the back flow pipe to control the back flow of the filtered water for back washing of the membrane.

The backwash pump 50 is installed downstream of the backwash valve 60, and pumps backwash water backflowed into the backflow pipe by the backwash valve 60, and is connected to each of the separator filters 21, 22, and 23. It will be branched and fed to the reverse branch office.

The backwash water valves 41, 42, and 43 are respectively installed in respective backwash engines connected to the respective separator filters 21, 22, and 23, respectively, to supply the backwash water branched by the backwash pump 50. The subdivision engine is opened and closed for control.

The backwash water valves 41, 42 and 43 of the present embodiment. It consists of three backwash water valves: a first backwash water valve 41, a second backwash water valve 42, and a third backwash water valve 43, but with two or four backwash water valves, similar to a separator filter. Of course, it is possible.

In addition, the membrane filter device of the present embodiment, the cleaning agent is introduced into the backwash water flowed back to each of the separator filters (21, 22, 23) between the backwash pump (50) and the backwash water valves (41, 42, 43). The detergent injector 70 is connected and installed.

Therefore, the cleaning agent is introduced into the backwashing water during the backwashing of the separators of each of the separator filters 21, 22, and 23 by the detergent injector 70, thereby improving the backwashing efficiency of the separator.

In addition, the input amount control valve 71 is installed in the detergent input unit 70 so as to adjust the input amount of the detergent according to the flow rate of the backwash water flowing back to each of the membrane filters 21, 22, and 23.

In the filtration process of the membrane filter apparatus of this embodiment as shown in FIG. 2, each filtration pump 11, 12, 13 connected to each separation membrane filter 21, 22, 23 is operated, and each filtrate valve 31 is carried out. , 32, 33) to discharge the filtered water to the subsequent process.

At this time, each of the backwash water valves 41, 42, and 43 connected to each of the separator filters 21, 22, and 23 is closed, the backwash valve 60 is closed, and the backwash pump 50 is stopped to remove the filtered water. It will block backflow.

As shown in FIG. 3 and in the back washing step of the membrane filtration apparatus of this embodiment, the first filtration pump 11 connected to the first membrane filter 21 among the plurality of membrane filters 21, 22, 23 is stopped and the first filter pump 11 is stopped. 1 Closes the filtrate valve 31 and opens the first backwash valve 41, and the second filtration pump 12 and the third filtration connected to the second separator 22 and the third separator 23. The pump 13 is operated, the second filtered water valve 32 and the third filtered water valve 33 are opened, and the second backwash water valve 42 and the third backwash water valve 43 are closed.

At this time, the backwash valve 60 is opened and the backwash pump 50 is operated so that a part of the filtered water discharged from the second separator 22 and the third separator 23 is flowed back to the first separator 21. The cleaning agent is introduced into the backwashing water by the cleaning agent injector 70 to backwash the separation membrane of the first separation membrane filter 21.

In addition, the flux of each backwash water is maintained at 0.5 to 5 times the filtration flux, and the backwash time is preferably 10 seconds to 2 minutes, and the pressure of the backwash water is maintained at 1 to 5 times the intermembrane pressure of the membrane filter. It is desirable to.

In particular, in this case, in the second membrane filter 22 and the third membrane filter 23 in which the filtration process is performed, as shown in the filtration process of FIG. Since the flow rate plus the backwash flow rate required for backwashing is processed, even if the filtration process is interrupted due to backwashing of the first separation membrane filter 21, the flow rate of the entire membrane filtration device is uniformly processed.

Therefore, the membrane filter device of the present embodiment does not supply the backwash water from the treated water storage tank for separately storing the filtered water at the time of backwashing of the separation membrane, and by backwashing the separation membrane by backflowing a part of the filtered water discharged in a subsequent process to the separation membrane filter, The space efficiency of the membrane filtration system can be improved by removing the space for the separate treatment water storage tank, and since part of the filtered water is directly used as the backwash water of the membrane during the membrane filtration process, it may be caused by the retention of the treated water storage tank of the filtered water. By preventing contamination, it is possible to prevent re-contamination of the membrane by back washing of contaminated filtered water and improve washing efficiency.

In addition, as shown in Figure 4, by using the drive pressure of the filtered water discharged in the filtration step of the membrane filter as the drive pressure of the post-treatment unit, it is possible to reduce the energy required for the drive pressure of the post-treatment unit to increase the efficiency of energy. Will be.

That is, the present embodiment (the thick solid line) after the membrane is a feed-side drive pressure of the filtration device (P _in1) decreases the exhaust side drive pressure (P _out1), a small amount of the membrane filtration device as the progress of filtration of the membrane filtration device of the It is used as it is the supply side drive pressure P _{in2 of the} treatment section and is maintained up to the discharge side drive pressure P _out2 of the post treatment section.

However, the supply pressure P _in1 of the membrane filter device of the conventional example (fine solid line) is discharged to the discharge side P of the membrane filter device as the filtered water is discharged after being stored in the treated water reservoir in the filtration process of the membrane filter device. _out1 ) is lost and excessive pressure loss (ΔP _loss ) occurs between the membrane filter unit and the aftertreatment unit.

Accordingly, the conventional example membrane filtration apparatus just the exhaust side drive pressure (P _out1) adding the drive of, for use as a feed-side drive pressure (P _in2) of the processing unit then to compensate for the loss of pressure drop (△ P _loss) from the filtration device the need for additional power for the pressure (△ P _add), but it uses the present embodiment the membrane filtration unit is the exhaust side drive pressure (P _out1) supply-side drive pressure (P _in2) of the processing unit after the membrane filtration unit, No additional power is needed to compensate for the pressure loss, which improves the energy efficiency of the membrane filter.

Hereinafter, with reference to the accompanying drawings, a film cleaning method of the membrane filtration device of this embodiment will be described in detail.

As shown in Figure 3 and 5, the membrane cleaning method of the membrane filter device of the present embodiment is part of the filtered water closing step (S10), the remaining filtered water opening step (S20), filtrate backflow step (S30), washing agent input step ( S40), and part of the backwash water opening and the remaining backwash water closing step (S50) is made to backwash the separation membrane of some of the membrane filter.

Part of the filtered water closing step (S10) to stop the first filtration pump 11 connected to the first membrane filter 21 of the plurality of membrane filters (21, 22, 23) and closes the first filtrate valve (31) Done.

In the remaining filtrate opening step (S20), the second filtration pump 12 and the third filtration pump 13 connected to the second separator 22 and the third separator 23 are operated, and the second filter valve ( 32 and the third filtrate valve 33 are opened.

In the filtered water backflow step (S30), the backwash valve 60 is opened and the backwash pump 50 is operated so that a part of the filtered water discharged from the second separator 22 and the third separator 23 is separated from the first separator. 21) reversed

In the cleaning agent input step (S40), the cleaning agent is introduced by the cleaning agent injector 70 into the backwash water in which the filtrate is counterflowed to the first separator filter 21.

In part of the backwash water opening and the remaining backwash water closing step (S50), the first backwash water valve 41 connected to the first separator filter 21 is opened, and the second backwash valve 42 and the third backwash valve are opened. Closing the 43, the backwash water is supplied only to the first separator filter 21 to backwash the separator of the first separator filter 21.

As described above, according to the present invention, by using a part of the filtered water filtered in the membrane filtration process as the backwash water of the separation membrane, the treated water storage tank can be removed from the membrane filtration device, thereby providing an effect of improving space efficiency. do.

In addition, it is possible to prevent contamination of the backwash water which may occur due to retention in the treated water storage tank of the filtered water, and to prevent the recontamination of the membrane by the contaminated backwash water, thereby improving the washing efficiency of the membrane. In addition, it is possible to improve the backwashing efficiency of the separator by adding a detergent to the backwashing water.

In addition, by using the driving pressure of the filtered water discharged from the membrane filtration process as the driving pressure of the post-treatment process, a driving facility for supplementing the driving pressure required for driving the post-treatment process is unnecessary, which can increase the energy efficiency of the entire water treatment process. Provide effect.

The present invention described above can be embodied in many other forms without departing from the spirit or main features thereof. Therefore, the above embodiments are merely examples in all respects and should not be interpreted limitedly.

The present invention provides a membrane filter apparatus without a treated water storage tank using a portion of the filtered water treated in the membrane filtration process as a backwash water of the membrane without providing a separate treated water storage tank for membrane backwashing and filtered water storage in the membrane filtration apparatus. Provide a cleaning method.

Claims (6)

1. A membrane filter device for branching feed water and filtering by a separation membrane,

   A plurality of filtration pumps for supplying each of the branched feed water;

   A plurality of separator filters for filtering the feed water pumped by the respective filtration pumps by a separator;

   A plurality of filtrate valves for opening and closing the discharge of the filtrate treated in each of the separator filters;

   A backwash valve installed downstream of the filtrate valve to open and close a counter flow of the filtrate so that a part of the filtered filtrate is returned to the separator filter to backwash the separator;

   A backwash pump pumping the backwash water flowed back by the backwash valve and branching to each of the separator filters; And

   And a plurality of backwash water valves each of which opens and closes a supply of backwash water branched by the backwash pump.
2. The method of claim 1,

   Membrane filtration device without a treatment water storage tank, characterized in that between the backwash pump and the backwash valve, a detergent injector for introducing a detergent into the backwash water.
3. The method of claim 2,

   The membrane filter system without a treatment water storage tank, characterized in that the detergent input device, the input amount control valve is installed to adjust the input amount of the detergent.
4. The method of claim 1,

   When the membrane is backwashed, the filtration pump connected to any one of the plurality of membrane filters is stopped, the filtration water valve is closed, the backwash water valve is opened, the filtration pump connected to the remaining membrane filter is operated, and the filtration water valve is turned on. Membrane filtration device without treatment water reservoir, characterized in that the opening and closing the backwash water valve.
5. As a membrane cleaning method for a membrane filtration device without the treated water storage tank according to claim 1,

   Stopping the filtration pump connected to any one of the plurality of separator filters and closing the filtrate valve;

   Operating a filtration pump connected to the remainder of the plurality of separator filters and opening the filtrate valve;

   Opening the backwash valve and operating a backwash pump to backflow the filtrate of the membrane filter; And

   And opening the backwash water valve connected to the separation membrane filter in which the filtration pump is stopped, and closing the remaining backwash valve.
6. The method of claim 5,

   Membrane cleaning method of the membrane filter apparatus without a treated water storage tank further comprises the step of introducing a washing agent to the backwash water between the backflow step of the filtered water and the opening step of the backwash water valve.

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