JP2011083660A - Filter member cleaning system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter member cleaning system which can inhibit the inclusion of treated water into a cleaning fluid while curbing the plug-up of a filter member at a filter treatment device. <P>SOLUTION: This filter member cleaning system comprises the following components: the filter member 23, the filter treatment device 2, a treated water line L2, a cleaning fluid line L4 branching out of the treated water line L2, a rinsing water line L5 branching out of the cleaning fluid line L4, a raw water circulation means 3 for circulating the treated water W2 through the treated water line L2, a cleaning fluid circulation means 4 for circulating the cleaning fluid W3 through the cleaning fluid line L4 and the treated water line L2, a rinsing water circulation means 5 for circulating the rinsing water through a rinsing water line L5, the cleaning fluid line L4 and the treated water line L2, and a control means 9 for controlling a raw water circulation means 3, the cleaning fluid circulation means 4 and the rinsing water circulation means 5. In addition, the control means 9 circulates the cleaning fluid W3 and stops the circulation of the cleaning fluid W3 after the lapse of a specified time. Further, after that, the rinsing water is made to circulate. Then, the circulation of the rising water is stopped after the lapse of a specified time, and after this operation, the treated water W2 is made to circulate. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a filtration member cleaning system for cleaning a filtration member such as a filtration membrane module in a filtration apparatus that constitutes a water treatment system.

  Conventionally, water treatment systems that produce high-purity treated water (purified water) from raw water such as factory wastewater and domestic wastewater, and that can be used as various process water, intermediate water, and miscellaneous water are known. Yes. In a water treatment system that performs such wastewater treatment, for example, a water purification technique based on a membrane separation activated sludge method is used for raw water. In the membrane separation activated sludge method, in order to separate activated sludge and treated water, filtration treatment is performed by a filtration treatment apparatus.

  The filtration apparatus is immersed in a filtration water tank that also serves as an aeration tank as a filtration member, and passes raw water (raw water in which organic substances are decomposed by the action of microorganisms) from the primary side to the secondary side. It has a filtration membrane module that separates activated sludge and treated water. According to the filtration apparatus, the raw water can be filtered by allowing the raw water to pass through the filtration membrane module from the primary side toward the secondary side.

  Here, when the filtration treatment apparatus repeats the filtration treatment, the filtration membrane module is blocked by impurities such as activated sludge trapped by the filtration membrane module. Therefore, it is necessary to back-clean the clogged filtration membrane module to remove impurities attached to the filtration membrane module. In the reverse cleaning of the filtration membrane module, a cleaning liquid or the like is supplied from the secondary side to the primary side to clean the filtration membrane module (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2000-300969

  By the way, in the reverse cleaning of the membrane filter module, the cleaning liquid may be supplied to the membrane filter module using a part of the line connected to the secondary region of the membrane filter module. In this case, the cleaning liquid may remain in the line after the cleaning liquid is supplied. Therefore, when the filtration process is resumed after the cleaning, there is a problem that the cleaning liquid remaining in the line is mixed into the treated water.

  An object of this invention is to provide the filtration member washing | cleaning system which can suppress mixing of the washing | cleaning liquid to process water, suppressing generation | occurrence | production of obstruction | occlusion with respect to the filtration member in a filtration processing apparatus.

  The present invention has a filtration member that passes raw water from the primary side toward the secondary side and filters the raw water, and a primary side region and a secondary side region that are partitioned by the filtration member, from the primary side region A filtration device that performs raw water filtration by passing raw water through the filtration member toward the secondary region, a treated water line connected to the secondary region of the filtration device, and the treated water line A cleaning liquid line branched from the middle of the cleaning liquid line, a rinsing water line branched from the middle of the cleaning liquid line, and a treated water obtained by filtering the raw water while passing the raw water from the primary side to the secondary side of the filtration member. Raw water distribution means for distributing to the treated water line, and cleaning for circulating the cleaning liquid through the cleaning liquid line and the treated water line so that the cleaning liquid passes from the secondary side to the primary side of the filtration member. Distribution means, and rinsing water distribution means for distributing the rinsing water so that the rinsing water passes from the secondary side to the primary side of the filtration member via the rinsing water line, the cleaning liquid line, and the treated water line. Control means for controlling the raw water circulation means, the cleaning liquid circulation means and the rinsing water circulation means, and the control means causes the cleaning liquid to circulate by the cleaning liquid circulation means and stops the flow of the cleaning liquid after a predetermined time has elapsed. Then, the rinsing water is circulated by the rinsing water circulation means, the rinsing water is stopped after a predetermined time has elapsed, and then the treated water is circulated by the raw water circulation means.

  Moreover, it is preferable that a filtration member washing | cleaning system uses treated water for rinse water.

  ADVANTAGE OF THE INVENTION According to this invention, the filtration member washing | cleaning system which can suppress mixing of the washing | cleaning liquid to treated water can be provided, suppressing generation | occurrence | production of obstruction | occlusion with respect to the filtration member in a filtration processing apparatus.

It is a lineblock diagram showing filtration member washing system 1 concerning an embodiment of the present invention. It is a flowchart which shows an example of operation | movement of the filtration member washing | cleaning system shown in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram showing a filtration member cleaning system 1 according to an embodiment of the present invention.
A filtration member cleaning system 1 shown in FIG. 1 constitutes a part of a water treatment system. The water treatment system, for example, removes impurities such as suspended solids from raw water W1 such as factory wastewater and domestic wastewater, and uses treated water (purified water) W2 that can be reused as various process water, intermediate water, miscellaneous water, etc. Generate.

  As shown in FIG. 1, the filtration member cleaning system 1 according to the present embodiment includes a filtration device 2 that performs a filtration process; a first filtration pump 3 and a second filtration pump 30 as raw water circulation means; a washing liquid circulation means. A cleaning pump 4 as a rinsing water distribution means, a rinsing pump 5 as a rinsing water distribution means, a treated water tank 6 in which treated water W2 is stored; a cleaning liquid tank 7 in which cleaning liquid W3 is stored; a pressure sensor 8; and a system as a control means The controller 9 is mainly configured.

  The filtration member cleaning system 1 according to the present embodiment further includes a raw water line L1, a first treated water line L2, a second treated water line L3, and a third treated water line L30 as treated water lines; a washing liquid line L4; Rinsing water line L5; first treated water valve 35; second treated water valve 31 and third treated water valve 33 as raw water circulation means; first treated water check valve 32; second treated water check valve 34; 1 cleaning liquid valve 43; second cleaning liquid valve 41 as cleaning liquid circulation means; cleaning liquid check valve 42; rinsing water valve 51 as rinsing water circulation means; rinsing water check valve 52 and the like.

In the filtration member cleaning system 1 according to the present embodiment, the raw water W1 is pretreated as necessary before the filtration treatment by the filtration treatment apparatus 2, and then the filtration treatment apparatus 2 via the raw water line L1. To be supplied.
The treated water (permeated water) W2 filtered by the filtration device 2 is any of the first treated water line L2 and the second treated water line L3, or the first treated water line L2 and the third treated water line L30. It is supplied to the treated water tank 6 through the line system and stored.

The cleaning liquid W3 stored in the cleaning liquid tank 7 is supplied to the filtration processing device 2 via the cleaning liquid line L4 and the first treated water line L2, and reversely cleans the filtration membrane module 23 as a filtering member.
Furthermore, a part of the treated water W2 stored in the treated water tank 6 is supplied as rinsing water to the first treated water line L2 via the rinsing water line L5 and the washing liquid line L4 (second washing liquid line L41 described later). Then, the line through which the cleaning liquid flows and the filter member are rinsed.
The “line” is a general term for lines capable of flowing a fluid such as a flow path, a path, and a pipeline.

Hereinafter, the filtration member washing | cleaning system 1 which concerns on this embodiment is explained in full detail.
Before the filtration process by the filtration apparatus 2, a necessary pretreatment is performed. The raw water W1 subjected to the pretreatment is supplied to the filtration apparatus 2 via the raw water line L1, as shown in FIG.

  The filtration apparatus 2 is an apparatus that performs a filtration process on the raw water W1. As shown in FIG. 1, the filtration device 2 includes a filtration membrane module 23 as a filtration member and a filtration water tank 24.

The filtration membrane module 23 includes a large number of filtration membranes (not shown), and impurities such as suspended substances are removed by the filtration membrane.
Examples of the filtration membrane include a microfiltration membrane (MF membrane), an ultrafiltration membrane (UF membrane), and a nanofiltration membrane (NF membrane). Examples of the shape of the filtration membrane include a flat membrane type, a hollow fiber membrane type, a tubular type, and a Nomoris type. These filtration membranes are required for treated water, for example, for water supply to thermal equipment such as steam boilers, hot water boilers, cooling towers, and water heaters, and for cleaning semiconductor manufacturing, electronic components, medical instruments, etc. It is appropriately selected and used depending on the application.

  The filtration water tank 24 can store the raw water W1 and the filtration membrane module 23 therein. The raw water W1 is supplied and stored in the filtered water tank 24 via the raw water line L1.

The filtration apparatus 2 in this embodiment performs a filtration process by a membrane separation activated sludge method (MBR; membrane bioreactor). In the case of MBR filtration treatment, a hollow fiber membrane type UF membrane or MF membrane is usually disposed and used while immersed in the filtration treatment water tank 24.
In the MBR, an air diffuser connected to an external blower is disposed below the filtration membrane module 23, and is configured to allow aeration during the filtration process (not shown).

  In addition, the filtration apparatus 2 includes a primary side area 21 that is an area inside the filtration water tank 24 and outside the filtration membrane module 23, and a secondary side area 22 that is an area inside the filtration membrane module 23. Have. That is, the primary side region 21 and the secondary side region 22 are partitioned by the filtration membrane module 23.

  According to the filtration device 2, the raw water W1 is circulated through the filtration membrane module 23 from the primary side region 21 toward the secondary side region 22, thereby performing the filtration treatment of the raw water W1 to obtain treated water (permeated water) W2. be able to. Further, the filtration membrane module 23 can be back-washed by passing the cleaning liquid W3 and the like from the secondary side toward the primary side.

The first treated water line L2 is a common line through which the treated water W2 and the cleaning liquid W3 circulate. One end of the first treated water line L2 is connected to the secondary side region 22 of the filtration device 2, that is, the inside of the filtration membrane module 23, and the other end is connected to the second treated water line L3 at the first connection portion J1. And the cleaning liquid line L4.
In the first treated water line L2, treated water W2 filtered by the filtration treatment device 2 flows from one end of the first treated water line L2 toward the other end, and the cleaning liquid W3 stored in the cleaning liquid tank, etc. Flows from the other end of the first treated water line L2 toward one end.

  A pressure sensor 8 is connected in the middle of the first treated water line L2. The pressure sensor 8 is a sensor that measures a pressure difference between the primary side region 21 and the secondary side region 22. More specifically, the pressure sensor 8 is a sensor that measures the pressure of the first treated water line L2 that has become negative due to the suction force of the first filtration pump 3 or the second filtration pump 30 described later. Since the atmospheric pressure is acting on the primary side region 21 of the filtration treatment device 2, the pressure sensor 8 measures the pressure of the first treated water line L 2, so The transmembrane pressure difference between the secondary region 22 (the transmembrane pressure difference between the primary side and the secondary side across the filtration membrane module 23) can be measured.

  The second treated water line L3 is a line that supplies the treated water tank 6 with treated water that has been filtered by the filtration treatment device 2 and that flows through the first treated water line L2. In the second treated water line L3, one end on the upstream side is connected to the first treated water line L2 and the cleaning liquid line L4 at the first connecting portion J1, and the other end on the downstream side is connected to the treated water tank 6. . In addition, the second treated water line L3 has a second connection portion J2 between one end portion and the other end portion, and has a third connection portion J3 between the second connection portion J2 and the other end portion.

  The first treated water valve 35 is connected between the first connection portion J1 and the second connection portion J2 in the second treated water line L3. According to the first treated water valve 35, the second treated water line L3 is disposed between the first connecting portion J1 and the second connecting portion J2 in the second treated water line L3 (downstream of the first connecting portion J1). Can be opened and closed.

  The first filtration pump 3 is connected between the second connection part J2 and the third connection part J3 in the second treated water line L3. The 1st filtration pump 3 can make the secondary side area | region 22 of the filtration processing apparatus 2 into a negative pressure via the 1st treated water line L2 and the 2nd treated water line L3 with the suction force. Thus, the first filtration pump 3 performs the first treatment on the treated water W2 obtained by filtering the raw water W1 while allowing the raw water W1 to pass from the primary region 21 to the secondary region 22 of the filtration device 2. It can distribute | circulate to the water line L2 and the 2nd treated water line L3.

  The second treated water valve 31 is connected between the second connection portion J2 and the first filtration pump 3 in the second treated water line L3. According to the second treated water valve 31, the second treated water line L3 can be opened and closed between the second connection portion J2 and the first filtration pump 3 (on the downstream side of the second connection portion J2).

  The first treated water check valve 32 is connected between the first filtration pump 3 and the third connection portion J3 in the second treated water line L3. The first treated water check valve 32 is a valve that allows fluid to flow only in the direction from the first filtration pump 3 toward the third connection portion J3.

  The third treated water line L30 is connected to the second treated water line L3. Specifically, one end portion of the third treated water line L30 is connected to the second connection portion, and the other end portion of the third treated water line L30 is connected to the third connection portion J3.

  The second filtration pump 30 is connected between one end and the other end of the third treated water line L30. The second filtration pump 30 makes the secondary side region 22 of the filtration treatment device 2 negative pressure through the first treated water line L2, the second treated water line L3, and the third treated water line L30 by the suction force. can do. Accordingly, the second filtration pump 30 performs the first treatment on the treated water W2 obtained by filtering the raw water W1 while allowing the raw water W1 to pass from the primary region 21 to the secondary region 22 of the filtration device 2. The second treated water between the water line L2, the second treated water line L3 between the first connecting part J1 and the second connecting part J2, the third treated water line L30, and the third connected part 3 and the treated water tank 6 It can be distributed to the line L3.

  The third treated water valve 33 is provided between the second connection portion J2 and the second filtration pump 30 in the third treated water line L30. According to the third treated water valve 33, the third treated water line L30 can be opened and closed between the second connection portion J2 and the second filtration pump 30 (downstream of the second connection portion J2).

  The second treated water check valve 34 is connected between the second filtration pump 30 and the third connection portion J3 in the third treated water line L30. The second treated water check valve 34 is a valve that allows fluid to flow only in the direction from the second filtration pump 30 toward the third connection portion J3.

  Here, the two treated water lines for circulating the treated water are the second treated water line L3 and the third treated water line L30. The first filtration pump 3 and the second filtration pump 30 are alternately arranged. This is to prevent pump failure due to overload by operating. In addition, if the treated water line has a plurality of systems and a filtration pump is provided for each of the treated water lines, even if one of them breaks down, it is possible to perform repair or replacement while continuing the filtration process. Furthermore, when the required amount of the treated water W2 increases, it becomes possible to increase the production amount of the treated water W2 by simultaneously driving a plurality of filtration pumps.

  The treated water tank 6 is a tank that stores treated water W2. The treated water tank 6 is connected to the other end portion (downstream end portion) of the second treated water line L3. The treated water tank 6 is connected to a line (not shown) for sending the treated water W3 to the demand point.

The cleaning liquid line L4 is a line that supplies the cleaning liquid W3 stored in the cleaning liquid tank 7 toward the first treated water line L2. The cleaning liquid line L4 includes a first cleaning liquid line L40, a second cleaning liquid line L41, and a fourth connection portion J4.
The first cleaning liquid line L40 has one end on the upstream side connected to the cleaning liquid tank 7, and the other end on the downstream side connected to one end on the upstream side of the second cleaning liquid line L41 at the fourth connection portion J4. The second cleaning liquid line L41 has one upstream end connected to the other end of the first cleaning liquid line L40 at the fourth connection J4 and the other downstream end connected to the first treated water line at the first connection J1. It is connected to the other end of L2. That is, the first cleaning liquid line L40 and the second cleaning liquid line L41 are connected at the fourth connection portion J4.
With the above configuration, the cleaning liquid line L4 is provided in the middle of the treated water line, that is, branched from the first connection portion J1 that connects the first treated water line L2 and the second treated water line L3.

  The cleaning liquid tank 7 is a tank that stores the cleaning liquid W3. The cleaning liquid tank 7 is connected to one end of the first cleaning liquid line L40 (the upstream end of the cleaning liquid line L4). As the cleaning liquid W3, a known cleaning liquid containing an oxidizing agent, a surfactant, a chelating agent, and the like can be used. In the case of MBR filtration, an aqueous sodium hypochlorite solution is preferably used.

  The cleaning pump 4 is connected between one end and the other end of the first cleaning liquid line L40. The cleaning pump 4 can make the cleaning liquid tank 7 have a negative pressure by the suction force. Accordingly, the cleaning pump 4 causes the cleaning liquid W3 stored in the cleaning liquid tank 7 to flow to the first treated water line L2 via the cleaning liquid line L4, and further, the filtration apparatus 2 via the first treated water line L2. The cleaning liquid W <b> 3 can be circulated from the secondary side region 22 toward the primary side region 21.

  The second cleaning liquid valve 41 is connected between the cleaning pump 4 and the fourth connection portion J4 in the first cleaning liquid line L40. According to the second cleaning liquid valve 41, the second cleaning liquid line L41 can be opened and closed between the cleaning pump 4 and the fourth connection part J4 in the second cleaning liquid line L41 (upstream of the fourth connection part J4). it can.

  The cleaning liquid check valve 42 is provided between the cleaning pump 4 and the cleaning liquid tank 7 in the first cleaning liquid line L40. The cleaning liquid check valve 42 is a valve that allows fluid to flow only in the direction from the end on the cleaning liquid tank 7 side in the first cleaning liquid line L40 toward the cleaning pump 4.

  The first cleaning liquid valve 43 is connected between the first connection part J1 and the fourth connection part J4 in the second cleaning liquid line L41. According to the first cleaning liquid valve 43, the cleaning liquid line L4 (upstream side of the first connecting part J1) between the first connecting part J1 and the fourth connecting part J4 (upstream side of the first connecting part J1) in the cleaning liquid line L4 (second cleaning liquid line L41). The second cleaning liquid line L41) can be opened and closed.

The rinsing water line L5 is a line that supplies the treated water W2 stored in the treated water tank 6 to the first treated water line L2 as rinsing water. The rinsing water line L5 has one upstream end connected to the treated water tank 6 and the other downstream end connected to the cleaning liquid line L4 at the fourth connecting portion J4.
With the above configuration, the rinsing water line L5 is provided in the middle of the cleaning liquid line L4, that is, branched from the fourth connection portion J4 connecting the first cleaning liquid line L40 and the second cleaning liquid line L41.

  The rinsing pump 5 is connected between one end and the other end of the rinsing water line L5. The rinsing pump 5 can make the treated water tank 6 have a negative pressure by the suction force. Thereby, the rinsing pump 5 causes the treated water W2 stored in the treated water tank 6 to flow as rinsing water to the first treated water line L2 via the rinsing water line L5 and the second cleaning liquid line L41. The rinsing water W5 can be circulated from the secondary side region 22 of the filtration apparatus 2 toward the primary side region 21 via the 1 treated water line L2.

  The rinsing water valve 51 is connected between the rinsing pump 5 and the fourth connection portion J4 in the rinsing water line L5. According to the rinsing water valve 51, the rinsing water line L5 can be opened and closed between the rinsing pump 5 and the fourth connecting portion J4 in the rinsing water line L5 (upstream side of the fourth connecting portion J4).

  The rinsing water check valve 52 is provided between the rinsing pump 5 and the treated water tank 6 in the rinsing water line L5. The cleaning liquid check valve 42 is a valve that allows fluid to flow only in the direction from the end of the rinsing water line L5 on the treated water tank 6 side toward the rinsing pump 5.

The system control device 9 controls the entire filtering member cleaning system 1 of the present embodiment. The system controller 9 is electrically connected to an element to be controlled among the elements constituting the filter member cleaning system 1. Specifically, the system controller 9 includes the first treated water valve 35, the second treated water valve 31, the first filtration pump 3, the third treated water valve 33, the second filtration pump 30, and the first cleaning liquid valve 43. The second cleaning liquid valve 41, the cleaning pump 4, the rinsing water valve 51 and the rinsing pump 5 are electrically connected to control each of them.
In addition, the system control device 9 is electrically connected to the pressure sensor 8 and receives pressure difference value information measured by the pressure sensor 8.

The system control device 9 includes a determination unit 91 and a control unit 92.
The determination unit 91 is electrically connected to the pressure sensor 8. The determination unit 91 can set a pressure difference threshold value, and performs determination such as activation of the cleaning pump 4 based on the set pressure difference threshold value. For example, when the pressure difference measurement value measured by the pressure sensor 8 is equal to or greater than the pressure difference threshold value, the determination unit 91 determines the activation of the cleaning pump 4 or the like. The pressure difference threshold value is appropriately set by an input operation by an operator, for example.

The controller 92 includes a first treated water valve 35, a second treated water valve 31, a first filtration pump 3, a third treated water valve 33, a second filtration pump 30, a first cleaning liquid valve 43, and a second cleaning liquid valve. 41, electrically connected to the washing pump 4, the rinsing water valve 51 and the rinsing pump 5.
The control unit 92 performs control of alternately operating the first filtration pump 3 and the second filtration pump 30 during the filtration process of the filtration apparatus 2 to send the treated water W2 to the treated water tank 6. In the alternate operation of the pump, the pump to be operated is switched every time the pump is operated for a certain time or every time a predetermined flow rate is supplied. During operation of the first filtration pump 3, the second treated water valve 31 is opened while the third treated water valve 33 is closed. Conversely, during operation of the second filtration pump 30, the third treated water valve 33 is opened while the second treated water valve 31 is closed.

  Further, the control unit 92 performs a cleaning process on the filtration membrane module 23 based on a predetermined regular cleaning timing or a determination result by the determination unit 91. Specifically, the first treated water valve 35 and the second treated water valve 31 are opened and closed (or the first treated water valve 35 and the third treated water valve 33 are opened and closed), the first filtration pump 3 (or the second treated water valve 33). Control of starting and stopping of the filtration pump 30), opening and closing of the first cleaning liquid valve 43 and the second cleaning liquid valve 41, starting and stopping of the cleaning pump 4, and the like are performed.

Furthermore, the control part 92 performs the rinse process of the 1st process water line L2, after performing the above-mentioned control which concerns on a washing process. In detail, control such as opening and closing of the rinsing water valve 51 and starting and stopping of the rinsing pump 5 are performed. More specifically, the controller 92 causes the cleaning pump 4 to pass the cleaning liquid W3 from the secondary side of the filtration membrane module 23 toward the primary side via the cleaning liquid line L4 and the first treated water line L2. The cleaning liquid W3 is circulated, and the flow of the cleaning liquid W3 is stopped after a predetermined time has elapsed. Thereafter, treated water W2 as rinsing water passes from the secondary side to the primary side of the filtration membrane module 23 through the rinse water line L5, the second cleaning liquid line L41, and the first treated water line L2 by the rinsing pump 5. Thus, the treated water W2 is circulated, and the circulated water W2 is stopped after a predetermined time has elapsed. Thereafter, the treated water W2 obtained by filtering the raw water by the filtration device 2 is circulated to the second treated water line L3 by the first filtration pump 3 (or to the third treated water line L30 by the second filtration pump 30). Let
The term “periodic cleaning” refers to cleaning performed periodically at a predetermined frequency regardless of the pressure difference measurement value. The regular cleaning is performed, for example, every predetermined time.

  Next, an example of the operation of the filtration member cleaning system 1 according to the present embodiment will be described with reference to FIG. FIG. 2 is a flowchart showing an example of the operation of the filtration member cleaning system 1 shown in FIG.

  In the present embodiment, in the filtration member cleaning system 1, after the filtration processing of the filtration membrane module 23 (predetermined periodic cleaning or cleaning processing based on the determination result by the determination unit 91) is performed, the rinsing water line L5, the second An example of one cycle until the cleaning liquid line L41, the first treated water line L2, and the filtration membrane module 23 are rinsed will be described.

  As shown in FIG. 2, in step ST <b> 1, after the cleaning process (predetermined periodic cleaning or the cleaning process based on the determination result by the determination unit 91) is performed, the pressure sensor 8 The pressure difference between the primary side region 21 and the secondary side region 22 is measured. That is, the pressure sensor 8 has a transmembrane differential pressure between the primary side region 21 and the secondary side region 22 of the filtration processing device 2 (transmembrane differential pressure between the primary side and the secondary side across the filtration membrane module 23. ). The pressure difference measurement value measured by the pressure sensor 8 is input to the determination unit 91 of the system control device 9.

  In step ST2, the determination unit 91 determines whether the pressure difference between the primary side region 21 and the secondary side region 22 of the filtration device 2 is equal to or greater than a predetermined pressure difference threshold based on the input pressure difference measurement value. It is determined whether it is lower than a predetermined pressure difference threshold. When the pressure difference between the primary side region 21 and the secondary side region 22 of the filtration apparatus 2 is equal to or greater than a predetermined pressure difference threshold value (YES), the process proceeds to step ST3. When the pressure difference between the primary side region 21 and the secondary side region 22 of the filtration apparatus 2 is lower than the predetermined pressure difference threshold value (NO), the process proceeds to step ST11.

  When the pressure difference between the primary side region 21 and the secondary side region 22 of the filtration apparatus 2 is equal to or greater than a predetermined pressure difference threshold, impurities such as activated sludge adhere to the filtration membrane module 23 and are in a tendency to accumulate It is in. That is, the filtration membrane module 23 may eventually be blocked. Therefore, it progresses to step ST3 and performs the washing process (back washing) of the filtration membrane module 23.

  On the other hand, when the pressure difference measurement value is lower than the pressure difference threshold value (NO), it is determined whether or not it is a predetermined periodic cleaning timing. When a predetermined time has elapsed since the previous periodic cleaning and the timing of the next periodic cleaning is reached (YES), the process proceeds to step ST3. On the other hand, when it is not the timing of the next periodic cleaning (NO), the process returns to step ST1.

  In step ST3, the control unit 92 of the system control device 9 performs control to close the first treated water valve 35 of the second treated water line L3. Thereafter, when the first filtration pump 3 is being activated, the control unit 92 performs control to stop the first filtration pump 3 and close the second treated water valve 31. On the contrary, when the second filtration pump 30 is activated, the second filtration pump 30 is stopped and the third treated water valve 33 is closed. Thereby, the filtration process is stopped, and the circulation of the treated water in the first treated water line L2 and the second treated water line L3, or the first treated water line L2 and the third treated water line L30 is stopped.

  In step ST4, the control unit 92 performs control to open the first cleaning liquid valve 43 of the second cleaning liquid line L41. Thereafter, the rinsing pump 5 is started and the rinsing valve 51 is controlled to open. Thereby, the treated water W2 as the rinsing water is supplied from the treated water tank 6 to the filtration membrane module 23 of the filtration apparatus 2 through the rinsing water line L5, the second cleaning liquid line L41, and the first treated water line L2. The treated water W <b> 2 as the rinsing water flows into the filtered water tank 24 after passing through the filtration membrane module 23.

  In step ST <b> 5, the control unit 92 performs control for starting the cleaning pump 4 and opening the second cleaning valve 41. As a result, supply (distribution) of the cleaning liquid W3 via the cleaning liquid line L4 (the first cleaning liquid line L40 and the second cleaning liquid line L41) and the first treated water line L2 is started. As a result, the cleaning liquid W3 flowing through the second cleaning liquid line L41 and the first processing water line L2 is mixed with the cleaning liquid W3, and the cleaning treatment of the filtration membrane module 23 is performed with the cleaning liquid W3 diluted with the processing water W2 ( Reverse cleaning) is performed. The cleaning liquid W3 (the cleaning liquid W3 diluted with the treated water W2) flows into the filtered water tank 24 after passing through the filtration membrane module 23. The cleaning liquid W3 that has flowed into the filtered water tank 24 is discharged to the outside as necessary. For example, when the cleaning liquid W3 is a sodium hypochlorite aqueous solution, the atmosphere is obtained by aeration during the filtering process. It may be volatilized inside.

  Thereafter, in step ST6, step ST5 is repeated until a predetermined time elapses (NO). In step ST6, when a predetermined time has elapsed (YES), the process proceeds to step ST7.

  In step ST7, the control unit 92 performs control to stop the cleaning pump 4 of the first cleaning liquid line L40 and close the second cleaning valve 41. Thereby, the supply (circulation) of the cleaning liquid W3 through the cleaning liquid line L4 (the first cleaning liquid line L40 and the second cleaning liquid line L41) and the first treated water line is stopped, and the cleaning process (reverse cleaning) of the filtration membrane module 23 is performed. Ends.

  Thereafter, in step ST8, step ST7 is repeated until a predetermined time elapses (NO). That is, since the circulation of the cleaning liquid W3 is stopped, only the treated water W2 as the rinsing water flows through the second cleaning liquid line L41 and the first treated water line L2 via the rinsing water line L5. Then, after passing through the filtration membrane module 23, it flows into the filtration water tank 24. That is, the rinsing process of the second cleaning liquid line L41, the first treated water line L2, and the filtration membrane module 23 is performed. In step ST8, when a predetermined time has elapsed (YES), the process proceeds to step ST9.

  In step ST9, the control unit 92 performs control to stop the rinsing pump 5 of the rinsing water line L5 and close the rinsing valve 51. Thereby, the supply (circulation) of the treated water W2 as the rinsing water via the rinsing water line L5, the second cleaning liquid line L41, and the first treated water line L2 is stopped, and the second washed liquid line L41, the first treated water line. The rinsing process of L2 and the filtration membrane module 23 is completed.

  In step ST10, the control unit 92 performs control to close the first cleaning liquid valve 43 and open the first treated water valve 35. Then, the control part 92 performs control which starts the 1st filtration pump 3 (or 2nd filtration pump 30 of the 3rd treated water line L30) of the 2nd treated water line L3. Thereby, the filtration process is resumed, and the circulation of treated water in the first treated water line L2 and the second treated water line L3 (or the first treated water line L2 and the third treated water line L30) is resumed.

According to the filtration member cleaning system 1 according to the present embodiment, for example, the following effects are exhibited.
In the present embodiment, the filtration member cleaning system 1 passes the cleaning liquid W3 from the secondary side of the filtration membrane module 23 toward the primary side via the cleaning liquid line L4 and the first treated water line L2 (filtration membrane). After the cleaning process of the module 23), treated water W2 as rinsing water is circulated through the first treated water line L2 for a predetermined time. Therefore, it is possible to distribute the cleaning liquid W3 remaining in the first treated water line L2 after flowing through the first treated water line L2 during the cleaning process. Thereby, even when the filtration process is resumed after the cleaning process, it is possible to prevent the remaining cleaning liquid W3 from being mixed in the treated water W2 flowing through the first treated water line L2. As a result, mixing of the treated water W2 into the cleaning liquid W3 can be suppressed while suppressing the occurrence of clogging of the filtration membrane module 23.

  Further, by washing away the cleaning liquid W3 remaining in the first treated water line L2 with the treated water W2, it is possible to suppress the first treated water line L2 from being corroded by the cleaning liquid W3 such as a sodium hypochlorite aqueous solution.

  In the present embodiment, the treated water W2 that has been filtered and stored in the treated water tank 6 is used as rinsing water. Therefore, it is not necessary to provide a separate facility for rinsing water. Thereby, installation cost etc. can be held down.

  As mentioned above, although preferred embodiment of this invention was described, this invention can be implemented with a various form, without being limited to embodiment mentioned above.

  For example, in the present embodiment, the treated water W2 stored in the treated water tank 6 is used as the rinsing water, but is not limited thereto. For example, a configuration may be provided in which a rinsing water tank for storing rinsing water is separately provided and the rinsing water is supplied from the rinsing water tank.

  In the present embodiment, the control unit 92 activates the cleaning pump 4 and the rinsing pump 5 based on the elapse of a predetermined time in the cleaning process of the filtration membrane module 23 and the rinsing process of the first treated water line L2. However, the present invention is not limited to this. For example, the control unit 92 may control the activation of the cleaning pump 4 and the rinsing pump 5 based on the amount of water collected from the cleaning liquid W3 and the treated water W2 as rinsing water.

  In the present embodiment, the control unit 92 as the control unit controls the ON / OFF of the start of the first filtration pump 3, but is not limited thereto. The control unit 92 can also control the amount and concentration of the cleaning liquid, for example.

  Further, the measurement of the pressure difference by the pressure sensor 8 can be performed simultaneously with or immediately after the supply of the treated water W2 as the rinsing water by the rinsing pump 5.

  Moreover, in this embodiment, although the filtration processing apparatus 2 is equipped with the immersion type filtration membrane module 23 as a filtration member, it is not restrict | limited to this. The filtration processing apparatus 2 may be an apparatus including an external pressure type filtration membrane module, or may be an activated carbon filtration apparatus or a sand filtration apparatus using a granular filter medium.

  In the present embodiment, the first filtration pump 3 is constituted by a suction type pump. However, when the filtration apparatus includes an external pressure type membrane filter module, the first filtration pump 3 may be constituted by a discharge type pump. it can. In this case, the pressure difference measured by the pressure sensor 8 is measured as a positive pressure.

  In the present embodiment, the cleaning liquid W3 is mixed with the treated water W2 as rinsing water and used in a thin state (cleaning of the filtration membrane module 23), but is not limited thereto. For example, a cleaning liquid that has been generated in advance to an appropriate concentration may be used without being diluted with treated water as rinsing water.

DESCRIPTION OF SYMBOLS 1 Filtration member washing | cleaning system 2 Filtration processing apparatus 3 1st pump for filtration (raw water distribution means)
4 Cleaning pump (cleaning fluid distribution means)
5 Rinsing pump (Rinsing water distribution means)
8 Pressure sensor 9 System controller (control means)
21 Primary side region 22 Secondary side region 23 Filtration membrane module (filtration member)
31 Second treated water valve (raw water distribution means)
30 Second filtration pump (raw water distribution means)
33 Third treated water valve (raw water distribution means)
41 Cleaning liquid valve (cleaning liquid distribution means)
51 Rinsing water valve (Rinsing water distribution means)
L2 First treated water line L3 Second treated water line L4 Cleaning liquid line L5 Rinsing water line L30 Third treated water line W1 Raw water W2 Treated water W3 Cleaning liquid

Claims (2)

It has a filtration member that passes raw water from the primary side to the secondary side and filters raw water, and a primary side region and a secondary side region that are partitioned by the filtration member, and the primary side region to the secondary side region A filtration device for filtering the raw water by allowing the raw water to pass through the filtration member,
A treated water line connected to the secondary region of the filtration device;
A cleaning liquid line branched from the middle of the treated water line;
A rinsing water line that branches off from the middle of the cleaning liquid line;
Raw water circulation means for circulating the treated water, which is filtered from the raw water, to the treated water line while allowing the raw water to pass from the primary side to the secondary side of the filtration member;
Cleaning liquid distribution means for distributing the cleaning liquid so that the cleaning liquid passes from the secondary side to the primary side of the filtration member through the cleaning liquid line and the treated water line;
Rinsing water circulation means for circulating the rinsing water so that the rinsing water passes from the secondary side to the primary side of the filtration member through the rinsing water line, the washing liquid line, and the treated water line;
Control means for controlling the raw water circulation means, the cleaning liquid circulation means and the rinse water circulation means,
The control means causes the cleaning liquid to flow through the cleaning liquid flow means, stops the flow of the cleaning liquid after a predetermined time has elapsed, and then causes the rinse water flow means to flow through the rinse water and stops the flow of rinse water after the predetermined time has elapsed. Then, the filtration member washing | cleaning system which distribute | circulates treated water by the said raw | natural water distribution | circulation means.   The filtration member cleaning system according to claim 1, wherein treated water is used as rinsing water.

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