JPH10235166A - Treatment apparatus using spiral-shaped membrane element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a treatment system capable of being reduced in cost and size and having high reliability. SOLUTION: Raw water is supplied to a spiral-shaped membrane module 100 using a spiral-shaped membrane element by a pump 102. The spiral-shaped membrane module 100, leads out permeated water by whole quantity filtering. The spiral-shaped membrane element is constituted by winding independent or continuous envelope-shaped membrane around the outer peripheral surface of a water collecting pipe and inserting raw water spacers into the gap between the envelope-shaped membrane and covering the outer peripheral surface with an outer peripheral part passage material. Raw water is supplied from at least the outer peripheral part side of the spiral-shaped membrane element and permeated water is led out of the opening end of the water gathering pipe. This permeated water is directly supplied to a reverse osmosis membrane separator 103.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a processing system using a spiral type membrane element.

[0002]

2. Description of the Related Art A reverse osmosis membrane (RO membrane) separator is used for desalination of seawater and production of ultrapure water. As pretreatment of the reverse osmosis membrane separation apparatus, coagulation, sedimentation and sand filtration are mainly performed. In the coagulation / sedimentation / sand filtration, the quality of the treated water changes depending on the quality of the raw water, so that it is not possible to supply the treated water with stable water quality to the reverse osmosis membrane separation device. This limits the ability of reverse osmosis membrane separators.

Further, in recent years, a membrane separation technique has been applied as a pretreatment of a reverse osmosis membrane separation apparatus. For such a pretreatment, a hollow fiber membrane element is mainly used. FIG.
FIG. 1 is a diagram showing an example of a conventional water treatment system using a reverse osmosis membrane separation device. In FIG. 8, raw water such as river water is stored in a storage tank 201. Raw water in the storage tank 201 is supplied by a pipe 207.
To feed pump 202 through feed pump 20
2 to the hollow fiber membrane element 203. The hollow fiber membrane element 203 separates raw water into permeated water and concentrated water. The permeated water obtained by the hollow fiber membrane element 203 is passed through a pipe 208 as pre-treatment water to a storage tank 204.
Supplied to On the other hand, the concentrated water obtained by the hollow fiber membrane element 203 is returned to the storage tank 201 through the pipe 209.

The pre-treated water stored in the storage tank 204 is supplied to a pump 205 through a pipe 210,
Is supplied to the reverse osmosis membrane separation device 206. The reverse osmosis membrane separation device 206 separates pretreatment water into permeated water and concentrated water. The permeated water obtained by the reverse osmosis membrane separation device 206 is supplied to the outside of the system through a pipe 211. The concentrated water obtained by the reverse osmosis membrane separation device 206 is returned to the storage tank 201 through the pipe 212.

[0005]

In the conventional water treatment system described above, the pretreated water obtained by the hollow fiber membrane element 203 is temporarily stored in a storage tank 204, and the pretreated water in the storage tank 204 is reversed by a pump 205. It is necessary to supply to the osmosis membrane separation device 206. As described above, since the storage tank 204 and the pump 205 are required, the system cost increases and the system becomes large.

Further, the hollow fiber membrane element 203 has an advantage that a membrane area per unit volume (volume efficiency) can be increased, but has a disadvantage that the membrane is easily broken. When the hollow fiber membrane element 80 is broken, there is a problem that the quality of pretreatment water supplied to the reverse osmosis membrane separation device 206 is reduced.

An object of the present invention is to provide a highly reliable processing system which can be reduced in cost and size.

[0008]

Means for Solving the Problems and Effects of the Invention In the processing system according to the first invention, a plurality of independent or continuous envelope membranes are wound around the outer peripheral surface of a perforated hollow tube via a stock solution flow path material. A pump is provided on the upstream side of the spiral type membrane element that is turned, and a reverse osmosis membrane separation device is connected to the downstream side via a pipe, and the pump allows undiluted solution from the outer peripheral side and both ends of the spiral type membrane element. The permeated liquid supplied and drawn out from at least one open end of the perforated hollow tube is supplied to the reverse osmosis membrane separation device through a conduit.

In the spiral type membrane element used in the treatment system of the present invention, since the outer peripheral surface and both end surfaces are open without being covered with the exterior material, the undiluted solution is supplied to the outer peripheral side and both end portions of the membrane element. Supplied from the side,
Full volume filtration can be performed. Therefore, the pump provided upstream of the membrane element can be downsized, and the permeate can be directly sent to the reverse osmosis membrane separation device by the pressure of the pump.

In this case, the stock solution is supplied from the outer peripheral side and both ends of the membrane element, and pressure is applied to the membrane element from all directions. Therefore, even if the supply pressure of the stock solution is increased, the membrane element is not deformed. High pressure resistance can be obtained. Therefore, the stock solution can be supplied at a high pressure by the pump provided on the upstream side.

As described above, since a pump and a storage tank for supplying the permeate obtained by the spiral type membrane element to the reverse osmosis membrane separation device are not required, the system cost is reduced and the system is downsized. .

Further, since the pretreatment is performed using a spiral type membrane element made of a flat membrane, the separation performance can be maintained and the reliability is high. Further, unlike the coagulation / sedimentation / sand filtration method, the quality of the permeated water does not change depending on the quality of the raw water. Therefore, pretreatment water of stable water quality can always be supplied to the reverse osmosis membrane separation device, and the capacity of the reverse osmosis membrane separation device is not reduced.

Further, since the raw water is supplied from the outer peripheral side and both ends of the membrane element, contaminants are trapped at the outer peripheral side and both ends of the membrane element. Therefore,
For example, contaminants can be uniformly removed by backwashing with permeated water or the like. As a result, the quality of the pretreatment water can be maintained for a long period of time.

Further, according to the structure of the spiral type membrane element described above, dead space is not formed in the gap between the membrane element and the pressure vessel by the total filtration,
Fluid does not stay in the gap between the membrane element and the pressure vessel.Therefore, even when used for separation of a fluid containing organic matter, propagation of various germs such as microorganisms, generation of odor due to decomposition of organic matter, separation Problems such as decomposition of the film do not occur, and high reliability can be obtained.

Further, since pressure is applied to the membrane element from all directions and does not apply a pressure causing displacement in the axial direction, the envelope-shaped membrane wound around the perforated hollow tube is deformed into a bamboo shoot. There is no. This eliminates the need for a packing holder and an exterior material, thereby reducing the component cost and manufacturing cost of the membrane element.

In a processing system according to a second aspect of the present invention, a plurality of independent or continuous envelope-shaped membranes are wound around the outer peripheral surface of a perforated hollow tube via a stock solution flow path material, and one end is sealed. A pump is provided on the upstream side of the spiral type membrane element and a reverse osmosis membrane separation device is connected to the downstream side via a pipeline, and the undiluted solution is supplied from the outer peripheral side and the other end side of the spiral type membrane element by the pump. The permeate discharged from at least one open end of the perforated hollow tube is supplied to the reverse osmosis membrane separation device through a conduit.

In the spiral type membrane element used in the treatment system of the present invention, since the outer peripheral surface and one end surface are open without being covered with the exterior material, the undiluted solution is supplied to the outer peripheral side and one end portion of the membrane element. Supplied from the side,
Full volume filtration can be performed. Therefore, the pump provided upstream of the membrane element can be downsized, and the permeate can be directly sent to the reverse osmosis membrane separation device by the pressure of the pump.

In this case, since pressure is applied to the membrane element from all directions, even if the supply pressure of the stock solution is increased, the membrane element is not deformed, and high pressure resistance is obtained. Therefore, the stock solution can be supplied at a high pressure by the pump provided on the upstream side.

As described above, a pump and a storage tank for supplying the permeate obtained by the spiral type membrane element to the reverse osmosis membrane separation device are not required, so that the system cost is reduced and the system is downsized. .

Further, since the pretreatment is performed using a spiral type membrane element made of a flat membrane, the separation performance can be maintained and the reliability is high. Further, unlike the coagulation / sedimentation / sand filtration method, the quality of the permeated water does not change depending on the quality of the raw water. Therefore, pretreatment water of stable water quality can always be supplied to the reverse osmosis membrane separation device, and the capacity of the reverse osmosis membrane separation device is not reduced.

Further, since raw water is supplied from the outer peripheral side and one end of the membrane element, contaminants are trapped at the outer peripheral and one end of the membrane element. Therefore,
For example, contaminants can be uniformly removed by backwashing with permeated water or the like. As a result, the quality of the pretreatment water can be maintained for a long time.

In particular, in the above spiral type membrane element, a space for supplying the undiluted solution is not required on the sealed end side, so that the pressure vessel for housing the membrane element can be downsized. Further, by disposing the sealed end of the membrane element on the side of the undiluted solution inlet of the pressure vessel, it is possible to prevent dirt from being attached to the end face of the spiral membrane element due to the dynamic pressure of the undiluted solution during undiluted solution introduction. it can.

Also in the structure of the above spiral type membrane element, since dead space is not formed in the space between the membrane element and the pressure vessel by the whole amount filtration, the odor due to the propagation of various germs such as microorganisms and the decomposition of organic matter is eliminated. No problem such as generation of separation and decomposition of the separation membrane occurs, and high reliability can be obtained.

Further, since pressure is applied from all directions of the membrane element and does not apply a pressure which causes displacement in the axial direction, the envelope-shaped membrane wound around the perforated hollow tube is deformed into a bamboo shoot. There is no. This eliminates the need for a packing holder and an exterior material, thereby reducing the component cost and manufacturing cost of the membrane element.

In a processing system according to a third aspect of the present invention, a plurality of independent or continuous envelope-shaped membranes are wound around the outer peripheral surface of a perforated hollow tube via a stock solution flow path material, and both ends are sealed. A pump is provided on the upstream side of the spiral type membrane element, and a reverse osmosis membrane separation device is connected to the downstream side via a pipeline, and a stock solution is supplied from the outer peripheral side of the spiral type membrane element by the pump, and The permeated liquid derived from at least one open end of the empty tube is supplied to the reverse osmosis membrane separation device through a conduit.

In the spiral type membrane element used in the processing system of the present invention, since the outer peripheral surface is open without being covered with the outer material, the stock solution is supplied from the outer peripheral side of the membrane element, and the whole amount is filtered. It can be performed. Therefore, the pump provided upstream of the membrane element can be downsized, and the permeate can be directly sent to the reverse osmosis membrane separation device by the pressure of the pump.

In this case, since pressure is applied to the membrane element from all directions, the membrane element is not deformed even if the supply pressure of the stock solution is increased, and high pressure resistance is obtained. Therefore, the stock solution can be supplied at a high pressure by the pump provided on the upstream side.

As described above, since a pump and a storage tank for supplying the permeate obtained by the spiral type membrane element to the reverse osmosis membrane separation device are not required, the system cost is reduced and the system is downsized. .

Further, since the pretreatment is performed using a spiral type membrane element made of a flat membrane, the separation performance can be maintained and the reliability is high. Further, unlike the coagulation / sedimentation / sand filtration method, the quality of the permeated water does not change depending on the quality of the raw water. Therefore, pretreatment water of stable water quality can always be supplied to the reverse osmosis membrane separation device, and the capacity of the reverse osmosis membrane separation device is not reduced.

Further, since raw water is supplied from the outer peripheral side of the membrane element, contaminants are trapped at the outer peripheral section of the membrane element. Therefore, it is possible to uniformly remove contaminants by backwashing with, for example, permeated water. As a result, the quality of the pretreatment water can be maintained for a long time.

In particular, in the above-mentioned spiral type membrane element, a space for supplying the undiluted solution is not required at both ends which are sealed, so that the pressure vessel for accommodating the membrane element can be downsized. Further, by disposing one of the sealed both ends of the membrane element on the side of the undiluted liquid inlet of the pressure vessel, it is possible to prevent dirt from adhering to the end face of the spiral membrane element due to the dynamic pressure of the undiluted liquid when introducing undiluted liquid. be able to.

Also in the structure of the above spiral type membrane element, since dead space is not formed in the space between the membrane element and the pressure vessel by the whole amount filtration, the odor due to the propagation of various germs such as microorganisms and the decomposition of organic matter is eliminated. No problem such as generation of separation and decomposition of the separation membrane occurs, and high reliability can be obtained.

Furthermore, since pressure is applied from all directions of the membrane element and does not apply a pressure that causes displacement in the axial direction, the envelope-shaped membrane wound around the perforated hollow tube is deformed into a bamboo shoot. There is no. This eliminates the need for a packing holder and an exterior material, thereby reducing the component cost and manufacturing cost of the membrane element.

In the processing system according to the first, second and third inventions, another reverse osmosis membrane separation device may be connected to the downstream side of the reverse osmosis membrane separation device via a pipeline. In this case, the permeate is directly sent to the reverse osmosis membrane separation device by a pump provided upstream of the spiral membrane element, and the permeate obtained by the reverse osmosis membrane separation device is sent to another reverse osmosis membrane separation device. Sent directly. As described above, since a pump and a storage tank for supplying pretreatment water to a plurality of reverse osmosis membrane separation devices are not required, system cost is reduced,
In addition, the size of the system is reduced.

[0035] In the processing system according to the first, second or third aspect of the present invention, the concentrated liquid derived from the reverse osmosis membrane separation device may be returned upstream of the pump. Thereby, the concentrated liquid obtained by the reverse osmosis membrane separation device is pretreated again by the spiral type membrane element and sent to the reverse osmosis membrane separation device, so that the recovery rate is improved.

[0036]

FIG. 1 is a diagram showing a water treatment system according to one embodiment of the present invention.

In FIG. 1, raw water such as river water is stored in a storage tank 10.
Stored in 1. Raw water in the storage tank 101 is supplied to a pump 102 through a pipe 104, and supplied to the spiral membrane module 100 using a spiral membrane element described later by the pump 102. The spiral membrane module 100 derives permeated water by total filtration. The permeated water obtained by the spiral membrane module 100 is
Reverse osmosis membrane separator 1 through pipe 105 as pretreatment water
03 directly.

The reverse osmosis membrane separation device 103 separates the pretreated water into permeated water and concentrated water. Reverse osmosis membrane separation device 103
Is supplied to the outside of the system as treated water through a pipe 106. The concentrated water obtained by the reverse osmosis membrane separation device 103 is returned to the storage tank 101 through the pipe 107.

In the water treatment system of this embodiment, the spiral membrane module 100 draws out the permeated water by total filtration, so that the pump 102 provided upstream of the spiral membrane module 100 can be downsized.
Can be directly sent to the reverse osmosis membrane separation device 103 by the pressure of

As described above, the spiral type membrane module 1
Since a pump and a storage tank are not required to supply the permeated water obtained by the process 00 to the reverse osmosis membrane separation device 103, the system cost is reduced and the system is downsized.

FIG. 2 is a diagram showing a water treatment system according to another embodiment of the present invention. In FIG. 2, raw water such as river water is stored in a storage tank 101. Raw water in the storage tank 101 is supplied to a pump 102 through a pipe 104,
2 to a spiral-type membrane module 100 using a spiral-type membrane element described later. The spiral membrane module 100 derives permeated water by total filtration. The permeated water obtained by the spiral membrane module 100 is supplied to the reverse osmosis membrane separation device 103a through the pipe 105 as pretreatment water.

The reverse osmosis membrane separation device 103a separates the pretreated water into permeated water and concentrated water. Reverse osmosis membrane separation device 10
The permeated water obtained in 3a is supplied to the outside of the system as treated water through a pipe 106, and is supplied to a reverse osmosis membrane separation device 103b through a pipe 108. The concentrated water obtained by the reverse osmosis membrane separation device 103a is returned to the storage tank 101 through the pipe 107.

The reverse osmosis membrane separator 103b separates the treated water supplied from the reverse osmosis membrane separator 103a into concentrated water and permeated water. The permeated water obtained by the reverse osmosis membrane separation device 103b is supplied to the outside of the system as treated water through a pipe 109. The concentrated water obtained by the reverse osmosis membrane separation device 103b is returned to the storage tank 101 through the pipe 110.

In the water treatment system of this embodiment, since the spiral membrane module 100 extracts the permeated water by total filtration, the pump 102 provided upstream of the spiral membrane module 100 can be downsized.
The permeated water can be directly sent to the reverse osmosis membrane separation device 103a by the pressure of, and the permeated water obtained by the reverse osmosis membrane separation device 103a can be directly sent to the reverse osmosis membrane separation device 103b.

As described above, the spiral type membrane module 1
The reverse osmosis membrane separation device 103a
A pump and a storage tank are not required to supply the water to the reverse osmosis membrane separation device 103a, and a pump and a storage tank are not required to supply the permeated water obtained by the reverse osmosis membrane separation device 103b to the reverse osmosis membrane separation device 103b. And the size of the system is reduced.

FIG. 3 is a partially cutaway perspective view of a spiral-wound membrane element used in the water treatment system of FIGS. FIG. 4 is a cross-sectional view showing an example of the envelope-shaped membrane of the spiral membrane element shown in FIG. 3, and FIG.
It is a cross-sectional view which shows the other example of the envelope-shaped membrane of the spiral-type membrane element of FIG.

The spiral type membrane element 1 shown in FIG.
Includes a spiral-shaped membrane element 1a formed by winding a plurality of independent envelope-shaped membranes 3 or a plurality of continuous envelope-shaped membranes 3 on the outer peripheral surface of a water collecting pipe 2 composed of a perforated hollow pipe. . A raw water spacer (raw liquid flow path material) 4 is inserted between the envelope films 3 in order to prevent the envelope films 3 from adhering to each other and to reduce the film area, and to form a flow path for raw water. Have been. Spiral membrane element 1
The outer peripheral surface of a is covered with an outer peripheral channel material 5 made of a net formed of plastic, metal, rubber, fiber, or the like such as polypropylene, polyethylene, or polystyrene.

As shown in FIG. 4 and FIG.
Is formed by superposing two separation membranes 7 on both sides of a permeated water spacer (permeated liquid flow path material) 6 and bonding three sides thereof, and the opening of the envelope-shaped membrane 3 is formed on the outer periphery of the water collecting pipe 2. Attached to the surface. 10 kgf / c for the separation membrane 7
Low pressure reverse osmosis membranes, ultrafiltration membranes, microfiltration membranes, etc., operated at m ² or less are used.

In the example of FIG. 4, a plurality of envelope-shaped membranes 3 are formed by independent separation membranes 7, respectively. In the example of FIG.
A plurality of envelope membranes 3 are formed by folding a continuous separation membrane 7.

If the thickness of the raw water spacer 4 is larger than 0.5 mm, it becomes difficult to capture contaminants in the raw water at least at the outer peripheral portion of the membrane element 1. On the other hand, raw water spacer 4
If the thickness is smaller than 0.1 mm, the envelope-shaped films 3 are easily brought into contact with each other, and the film area is reduced. Therefore, the thickness of the raw water spacer 4 is 0.1 mm or more and 0.5 mm or more.
The following is preferred.

When the thickness of the outer peripheral channel member 5 is larger than 30 mm, the volumetric efficiency of the membrane element 1 with respect to the pressure vessel containing the membrane element 1 decreases. On the other hand, if the thickness of the outer peripheral portion flow path member 5 is smaller than 0.6 mm, it becomes difficult to discharge contaminants attached to at least the outer peripheral portion of the membrane element 1 during backflow washing of the permeated water to the outside of the system. Therefore, it is preferable that the thickness of the outer peripheral channel member 5 is 0.6 mm or more and 30 mm or less.

FIG. 6 shows the spiral type membrane element 1 shown in FIG.
FIG. 3 is a cross-sectional view of a spiral-type membrane module 100 using the same. As shown in FIG. 6, the pressure vessel (pressure-resistant vessel) 10
It is composed of a cylindrical case 11 and a pair of end plates 12a, 12b. A raw water inlet 13 is formed on one end plate 12a, and a raw water outlet 15 is formed on the other end plate 12b. A permeated water outlet 14 is provided at the center of the other end plate 12b.

The spiral membrane element 1 is housed in a cylindrical case 11, and both open ends of the cylindrical case 11 are sealed by end plates 12a and 12b, respectively. One end of the water collecting pipe 2 is fitted to the permeated water outlet 14 of the end plate 12b, and an end cap 16 is attached to the other end. End plate 1
A pipe 17 and a valve 18 are connected to the raw water outlet 15 of 2b.

During the operation of the spiral membrane element 1, raw water 51 is introduced into the pressure vessel 10 from the raw water inlet 13 of the pressure vessel 10. The raw water 51 is supplied from at least the outer peripheral side of the spiral membrane element 1 to the raw water spacer 4.
Along the space between the envelope-shaped membranes 3. In the example of FIG. 6, the raw water 51 enters between the envelope-shaped membranes 3 from the outer peripheral side and both end sides of the spiral membrane element 1. The permeated water that has passed through the separation membrane 7 flows into the water collecting pipe 2 along the permeated water spacer 6. Thereby, the permeated water outlet 14 of the pressure vessel 10
The permeated water 52 is taken out from the tank. In this way, total filtration is performed.

In this case, the thickness of the raw water spacer 4 is so small that contaminants such as turbid substances are captured at least at the outer peripheral portion (the outer peripheral portion and both ends in the example of FIG. 6) of the membrane element 1. A cake layer of a contaminant is formed on at least the outer peripheral portion of the device. At least the outer periphery of the membrane element 1 is subjected to cake filtration by the cake layer, and the inside of the membrane element 1 is subjected to membrane filtration by the separation membrane 7.

The raw water may be partially removed from the raw water outlet 15 by opening the valve 18. In this case, a flow of raw water can be formed at the outer peripheral portion of the membrane element 1. Thereby, a part of the contaminants can be discharged to the outside of the pressure vessel 10 while the sedimentation of the contaminants in the raw water is suppressed.

After filtration for a certain period of time, backwashing with permeated water is performed from the permeation side. During backwashing, the permeated water back-filtered from the water collection pipe 2 flows along the raw water spacer 4 at least toward the outer peripheral portion. Thereby, the contaminants captured at least at the outer peripheral portion of the membrane element 1 are easily peeled off. At this time, when the valve 18 is opened while supplying the raw water from the raw water inlet 13, the separated contaminants are discharged out of the system. As a result, the permeation flux is remarkably recovered as compared with before the backwashing.

In the above spiral type membrane element 1, since the permeated water is led out by the total filtration, no pressure difference occurs between the raw water side and the permeated water side. Therefore, when the above spiral type membrane element 1 is used in the water treatment system of FIG. 1, the permeated water can be directly sent to the reverse osmosis membrane separation device 103 by the pressure of the pump 102 provided upstream.

Further, since pressure is applied from all directions of the spiral type membrane element 1, even if the supply pressure of raw water is increased, the membrane element 1 is not deformed, and high pressure resistance is obtained. Therefore, when the above spiral type membrane element 1 is used in the water treatment system of FIG. 2, raw water can be supplied at a high pressure by the pump 102 provided upstream. This allows the permeated water to pass through the reverse osmosis membrane separation device 103
a and the permeated water obtained by the reverse osmosis membrane separation device 103a
3b can be sent directly.

Further, since the dead space S as shown in FIG. 8 is not formed in the gap between the membrane element 1 and the pressure vessel 10 by the above-described filtration mode, propagation of various germs such as microorganisms, There is no problem such as generation of offensive odor and decomposition of the separation membrane due to decomposition, and high reliability can be obtained.

Further, since pressure is applied to the membrane element 1 from all directions, the problem of deformation of the membrane element 1 does not occur, and the packing holder and the exterior material become unnecessary. Thereby,
The component cost and manufacturing cost of the membrane element 1 are reduced.

FIG. 7 is a front view showing another example of the spiral membrane element used in the water treatment system shown in FIGS. 1 and 2. In FIG. 7, the illustration of the outer peripheral channel material is omitted.

The spiral type membrane element 1 shown in FIG.
In, both end portions of the spiral membrane element 1a are sealed with a resin layer 19. In the spiral membrane element 1 shown in FIG. 7B, one end of the spiral membrane element 1 a is sealed with a resin layer 19.

In the spiral type membrane element 1 shown in FIGS. 7 (a) and 7 (b), the number of working steps at the time of manufacturing increases, but a space for supplying raw water to both ends or one end of the membrane element 1 becomes unnecessary. Therefore, the pressure vessel can be reduced in size, and the spiral membrane module in which the membrane element 1 is housed in the pressure vessel can be reduced in size.

Further, by arranging the end portion of the membrane element 1 sealed with the resin layer 19 on the raw water inlet side of the pressure vessel, dirt adheres to the end face of the membrane element 1 due to the dynamic pressure of the raw water when the raw water is introduced. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a diagram showing a water treatment system in one embodiment of the present invention.

FIG. 2 is a diagram showing a water treatment system according to another embodiment of the present invention.

FIG. 3 is a partially cutaway perspective view of a spiral-wound membrane element used in the water treatment system of FIGS. 1 and 2;

FIG. 4 is a cross-sectional view showing an example of an envelope-shaped membrane of the spiral membrane element shown in FIG.

5 is a cross-sectional view showing another example of the envelope-shaped membrane of the spiral-wound membrane element of FIG.

FIG. 6 is a sectional view of a spiral membrane module using the spiral membrane element of FIG. 3;

FIG. 7 is a front view showing another example of the spiral membrane element used in the water treatment system of FIGS. 1 and 2.

FIG. 8 is a diagram showing an example of a conventional water treatment system using a reverse osmosis membrane separation device.

[Description of Signs] 1 Spiral type membrane element 1a Spiral type membrane element 2 Water collecting pipe 3 Envelope type membrane 4 Raw water spacer 5 Peripheral flow path material 6 Permeated water spacer 7 Separation membrane 10 Pressure vessel 13 Raw water inlet 14 Permeated water outlet 51 Raw water 52 Permeated water 100 Spiral type membrane module 101 Storage tank 102 Pump 103, 103a, 103b Reverse osmosis membrane separation device

Claims (5)

[Claims] A pump is provided upstream and downstream of a spiral-type membrane element formed by winding a plurality of independent or continuous envelope-shaped membranes around the outer peripheral surface of a perforated hollow tube via a stock solution flow path material. A reverse osmosis membrane separation device is connected via a pipe line, and a stock solution is supplied from the outer peripheral side and both end sides of the spiral type membrane element by the pump, and from at least one open end of the perforated hollow tube. A processing system, wherein the derived permeate is supplied to the reverse osmosis membrane separation device through the conduit. 2. An upstream side of a spiral type membrane element in which a plurality of independent or continuous envelope-shaped membranes are wound around the outer peripheral surface of a perforated hollow tube via a stock solution flow path material and one end is sealed. A reverse osmosis membrane separation device is connected to the downstream side via a pipe line, and a stock solution is supplied from the outer peripheral side and the other end side of the spiral type membrane element by the pump. A processing system, wherein a permeate derived from at least one open end of an empty tube is supplied to the reverse osmosis membrane separation device through the conduit. 3. An upstream side of a spiral membrane element in which a plurality of independent or continuous envelope membranes are wound around the outer peripheral surface of a perforated hollow tube via a stock solution flow path material and both ends are sealed. A pump is provided and a reverse osmosis membrane separation device is connected to the downstream side via a pipeline, and a stock solution is supplied from the outer peripheral side of the spiral type membrane element by the pump, and at least one of the perforated hollow tubes is provided. A permeated liquid derived from an open end of the reverse osmosis membrane separation device is supplied to the reverse osmosis membrane separation device through the conduit. 4. The processing system according to claim 1, wherein another reverse osmosis membrane separation device is connected to a downstream side of the reverse osmosis membrane separation device via a pipeline. 5. The processing system according to claim 1, wherein the permeate discharged from the reverse osmosis membrane separation device is returned to an upstream side of the pump.