JP2000271458A - Spiral type membrane module and operation and washing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low cost, easily washable and highly reliable spiral type membrane module, and its operation method. SOLUTION: The spiral type membrane module is formed by loading a spiral type membrane element 1 in a pressure container 10. The spiral type membrane element 1 is constituted by covering a spiral-shaped membrane element consisting of a plurality of independent or continuous envelope-like membranes on the outer peripheral surface via raw water spacers with a separation membrane and further covering the resultant assembly with an outer peripheral part flow path material. A raw water inlet 13 is provided on the pressure container 10 and a piping 19 for feeding raw water is connected to it. The piping 19 is further connected to a piping 20 for discharging washed liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a spiral type membrane module used for a membrane separation device such as a low pressure reverse osmosis membrane separation device, an ultrafiltration device and a microfiltration device, an operation method thereof and a cleaning method.

[0002]

2. Description of the Related Art In recent years, a membrane separation technique has been applied to a water purification technique, and a membrane separation technique has been applied as a pretreatment of a reverse osmosis membrane separation system used for seawater desalination and the like.
As a type of membrane used for such membrane separation, a microfiltration membrane or an ultrafiltration membrane capable of obtaining a high amount of permeated water is widely used, but recently, an ultra-low pressure of 10 kgf / cm ² or less has been used. Reverse osmosis membranes that provide a permeate volume have also been developed.

[0003] As a form of a membrane element used for membrane separation, a hollow fiber membrane element is often used in view of a membrane area per unit volume (volume efficiency). However, the hollow fiber membrane element has a disadvantage that the membrane is easily broken, and if the membrane is broken, the raw water mixes with the permeated water and the separation performance is reduced.

On the other hand, there is a spiral type membrane element as a form of a membrane element capable of increasing a membrane area. This spiral type membrane element has an advantage that separation performance can be maintained and reliability is high as compared with a hollow fiber membrane element.

FIG. 18 is a partially cutaway perspective view of a conventional spiral type membrane element, and FIG. 19 is an external perspective view of a conventional spiral type membrane element.

As shown in FIG. 18, a spiral membrane element 21 is composed of an envelope-shaped membrane (bag) by superposing separation membranes 26 on both sides of a permeated water spacer (permeate flow path material) 25 and bonding three sides thereof. Film) 23, and the envelope-shaped film 2
3 is attached to the water collecting pipe 22 formed of a perforated hollow pipe, and is wound spirally around the outer peripheral surface of the water collecting pipe 22 together with the net-shaped (net-shaped) raw water spacer 24 (raw water liquid passage material). Is done.

The raw water spacer 24 is provided for forming a flow path through which raw water passes between the envelope membranes 23. If the thickness of the raw water spacer 24 is small, the filling efficiency of the separation membrane 26 is increased, but clogging with the suspended substance occurs. Therefore, usually, the thickness of the raw water spacer 24 is about 0.7 mm to 3.0 m.
m.

A spiral membrane element using a zigzag corrugated raw water spacer (so-called corrugated spacer) for treating raw water containing a large amount of suspended substances, such as river water, has already been known.

As shown in FIG. 19, the outer peripheral surface of the spiral type membrane element 21 is covered with an exterior material 27 made of FRP (fiber reinforced plastic), a shrinkable tube or the like.
Packing holders 28 called anti-telescopes are respectively attached to both ends.

FIG. 20 is a cross-sectional view showing an example of a conventional method of operating a spiral type membrane element. As shown in FIG. 20, the pressure vessel (pressure-resistant vessel) 30 includes a cylindrical case 31 and a pair of end plates 32a and 32b. A raw water inlet 33 is formed on one end plate 32a, and a concentrated water outlet 35 is formed on the other end plate 32b. A permeated water outlet 34 is provided at the center of the other end plate 32b.

A spiral type membrane element 21 having a packing 37 attached near one end of the outer peripheral surface is mounted in a cylindrical case 31, and both open ends of the cylindrical case 31 are sealed with end plates 32a and 32b, respectively. I do. One open end of the water collecting pipe 22 is fitted to the permeated water outlet 34 of the end plate 32b, and an end cap 36 is attached to the other open end.

During the operation of the spiral type membrane element 21, the raw water 51 is introduced into the first liquid chamber 38 from the raw water inlet 33 of the pressure vessel 30. As shown in FIG.
Is supplied from one end face side of the spiral membrane element 21. The raw water 51 flows in the axial direction along the raw water spacer 24, and is discharged as concentrated water 53 from the other end surface side of the spiral membrane element 21. As the raw water 51 flows along the raw water spacer 24, the permeated water 52 that has passed through the separation membrane 26 is collected along the permeated water spacer 25 by the water collecting pipe 2.
2 and discharged from the end of the water collecting pipe 22.

The permeated water 52 is supplied to the pressure vessel 30 shown in FIG.
Is taken out from the permeated water outlet 34 to the outside. Further, the concentrated water 53 is taken out of the second liquid chamber 39 in the pressure vessel 30 through the concentrated water outlet 35 to the outside.

[0014]

When the membrane element is operated, the membrane is clogged by suspended substances in the raw water, and the membrane flux is reduced. Therefore, although clogging is removed by performing chemical cleaning or the like to recover the membrane flux, the labor and cost required for chemical cleaning poses a problem. Therefore, in order to prevent clogging, for example, in a hollow fiber membrane element, backwashing with permeated water or air is periodically performed.

However, in the conventional spiral-type membrane element 21, the following problems occur when backwashing is performed.

FIG. 21 is a partially cutaway perspective view showing a backwashing operation in a conventional spiral type membrane element.
As shown in FIG. 21, permeated water 52 is introduced from the end of the water collecting pipe 22. Since the outer peripheral surface of the envelope film 23 wound around the water collecting pipe 22 is covered with the exterior material 27, the water collecting pipe 22
The permeated water 52 derived from the outer peripheral surface of the spiral membrane element 21 passes through the envelope-shaped membrane 23, flows in the axial direction inside the spiral membrane element 21 along the raw water spacer 24, and is discharged from the end of the spiral membrane element 21. You. Therefore, even if the backwashing is performed, contaminants such as turbid substances causing clogging of the membrane are easily captured by the raw water spacer 24 before being discharged from the end of the spiral membrane element 21. There is a problem that it is not sufficiently removed.

Further, a gap existing between the inner peripheral surface of the cylindrical case 31 of the pressure vessel 30 and the spiral membrane element 21 in FIG. 20 becomes a dead space S, and a stagnation (liquid pool) of fluid occurs. Spiral type membrane element 21
When used for a long time, the fluid staying in the dead space undergoes metamorphosis. In particular, when the fluid is a liquid containing an organic substance, germs such as microorganisms propagate, and the germs may decompose the organic substance to generate a bad smell or decompose the separation membrane. Leads to a decrease in

Further, in the conventional spiral type membrane element 21, raw water is supplied from one end of the spiral type membrane element 21 and discharged from the other end.
A packing holder 28 is required to prevent the envelope-shaped film 23 wound in 2 from being deformed into a bamboo shoot shape.
In addition, a pressure difference occurs between the raw water inflow side and the concentrated water outlet side due to the pressure loss due to the raw water spacer 24 and the pressure loss due to clogging, and the spiral membrane element 21 is deformed. In order to prevent this deformation, the outer peripheral surface of the envelope-like film 23 wound around the water collecting pipe 22 is covered with an exterior material 27 such as an FRP or a shrinkable tube. These increase component costs and manufacturing costs.

Further, it is necessary to obtain a sufficient film surface linear velocity in order to prevent the formation of cake due to contaminants in raw water, and for that purpose, a sufficient flow rate on the concentration side is required. If the flow rate on the concentration side is increased, the recovery rate per membrane element will be low, and the pump for supplying raw water will be large, and the system cost will be very large.

An object of the present invention is to provide a spiral-type membrane module which can be reduced in cost, is easy to clean, and has high reliability, and a method of operating the same.

Another object of the present invention is to provide a method for cleaning a spiral membrane module which can easily and reliably remove contaminants trapped in the spiral membrane element.

[0022]

Means for Solving the Problems and Effects of the Invention The operation method of the spiral membrane module according to the first invention is as follows.
Or a method of operating a spiral-type membrane module in which a plurality of spiral-type membrane elements are housed in a pressure vessel, wherein the spiral-type membrane element is formed of a plurality of envelopes independent or continuous on the outer peripheral surface of a perforated hollow tube. The membrane includes a spiral membrane element that is wound through a raw liquid flow path material, and the outer periphery of the spiral membrane element is covered with a liquid permeable material,
The outer peripheral surface side of the liquid-permeable material is wholly or partially covered with an outer peripheral channel material, the pressure vessel has one or more liquid ports, and one of the one or more liquid ports of the pressure vessel An undiluted solution is supplied from at least the outer peripheral side of the spiral membrane element through one of them, and a permeate is taken out from at least one open end of the perforated hollow tube.

According to the spiral membrane module operating method of the present invention, the stock solution is supplied from at least the outer peripheral side of the spiral membrane element, and the whole is filtered. In this case, contaminants are trapped at least at the outer periphery of the spiral-wound membrane element. Thereby, the load on the envelope-shaped membrane is reduced.

Further, since no dead space is formed in the gap between the spiral membrane element and the pressure vessel, liquid does not accumulate in the gap between the spiral membrane element and the pressure vessel. Therefore, even when used for separating a liquid containing an organic substance, problems such as propagation of microorganisms such as microorganisms, generation of offensive odor due to decomposition of the organic substance, and decomposition of the separation membrane do not occur, and high reliability can be obtained.

Further, a stock solution is supplied from at least the outer peripheral side of the spiral type membrane element, and pressure is applied to the spiral type membrane element from all directions, and no pressure which causes displacement in the axial direction is applied. The envelope-shaped membrane wound around the empty tube does not deform into a bamboo shoot. This eliminates the need for a packing holder and an exterior material, thereby reducing parts costs and manufacturing costs. Also, a high recovery rate can be obtained without using a large pump for supplying the stock solution. Thereby, the system cost is reduced.

Further, since pressure is applied to the spiral membrane element from all directions, the spiral membrane element does not deform even if the supply pressure of the stock solution is increased. Therefore, high pressure resistance can be obtained.

A method for operating a spiral membrane module according to a second aspect of the present invention is a method for operating a spiral membrane module in which one or more spiral membrane elements are housed in a pressure vessel. Includes 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 raw liquid flow path material, and the outer peripheral portion of the spiral membrane element is liquid permeable. The outer peripheral surface side of the liquid-permeable material is entirely or partially covered with the outer peripheral channel material, and the pressure vessel has a plurality of liquid ports, and among the plurality of liquid ports of the pressure vessel, An undiluted solution is supplied from at least the outer peripheral side of the spiral membrane element through one of the liquid ports, and a permeate is taken out from at least one open end of the perforated hollow tube, and constantly or intermittently. It is intended to take out from the other liquid entrance of the number of liquid inlet and outlet portions of the stock solution of the pressure vessel to the outside.

According to the spiral membrane module operating method of the present invention, the undiluted solution is supplied from at least the outer peripheral side of the spiral membrane element and filtration is performed. In this case, since the contaminants are captured at least at the outer peripheral portion of the spiral membrane element, the load on the envelope membrane is reduced.

Also, by removing a part of the supplied stock solution to the outside of the pressure vessel, the stock solution can be always or intermittently formed in the axial direction along the outer periphery of the spiral membrane element. It becomes possible. Such a flow of the stock solution makes it possible to suppress contaminants in the stock solution from adhering to at least the outer peripheral portion of the spiral membrane element, so that stable operation can be performed for a long period of time.

Further, since no dead space is formed in the gap between the spiral membrane element and the pressure vessel, liquid does not accumulate in the gap between the spiral membrane element and the pressure vessel. Therefore, even when used for separating a liquid containing an organic substance, problems such as propagation of microorganisms such as microorganisms, generation of offensive odor due to decomposition of the organic substance, and decomposition of the separation membrane do not occur, and high reliability can be obtained.

Further, a stock solution is supplied from at least the outer peripheral side of the spiral type membrane element, and pressure is applied to the spiral type membrane element from all directions and a pressure which causes displacement in the axial direction is not applied. The envelope-shaped membrane wound around the empty tube does not deform into a bamboo shoot. This eliminates the need for a packing holder and an exterior material, thereby reducing parts costs and manufacturing costs. Also, a high recovery rate can be obtained without using a large pump for supplying the stock solution. Thereby, the system cost is reduced.

Further, since pressure is applied to the spiral membrane element from all directions, the spiral membrane element does not deform even if the supply pressure of the stock solution is increased. Therefore, high pressure resistance can be obtained.

At least a part of the stock solution taken out of the pressure vessel may be returned to the supply side. In this case, at least a part of the undiluted solution taken out can be circulated, so that a permeate can be obtained with a high recovery rate.

A method for cleaning a spiral membrane module according to a third aspect of the present invention is a method for cleaning a spiral membrane module in which one or a plurality of spiral membrane elements are housed in a pressure vessel. Includes 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 raw liquid flow path material, and the outer peripheral portion of the spiral membrane element is liquid permeable. The outer peripheral surface side of the liquid permeable material is entirely or partially covered with the outer peripheral channel material, and the pressure vessel is
Alternatively, a cleaning liquid having a plurality of liquid ports is introduced from at least one open end of the perforated hollow tube, and the cleaning liquid derived from the outer peripheral surface of the perforated hollow tube is discharged from at least the outer peripheral portion of the spiral membrane element. Then, the liquid is taken out from one or more liquid ports of the pressure vessel.

In the above-mentioned spiral membrane element of the spiral membrane module, since at least the outer peripheral portion is open without being covered with the exterior material, the stock solution is supplied from at least the outer peripheral side of the spiral membrane element. , Filtration can be performed. In this case, contaminants are trapped at least at the outer periphery of the spiral-wound membrane element.

When the cleaning liquid is introduced from at least one open end of the perforated hollow tube at the time of cleaning, the cleaning liquid derived from the outer peripheral surface of the perforated hollow tube passes through the envelope-like membrane and flows along the stock solution flow path material. And is discharged from at least the outer peripheral portion of the spiral membrane element. As a result, the contaminants trapped on the membrane surface and at least the outer peripheral portion of the spiral membrane element are separated from the spiral membrane element and discharged together with the cleaning liquid from at least one liquid port of the pressure vessel to the outside. Therefore, the contaminants trapped on the membrane surface and at least the outer peripheral portion of the spiral membrane element can be uniformly removed.

The washing liquid is a permeate, and at least a part of the permeate taken out of the pressure vessel may be returned to the stock solution supply side. In this case, at least a part of the permeate taken out can be circulated, so that the permeate can be obtained at a high recovery rate.

A method for cleaning a spiral-wound membrane module according to a fourth aspect of the present invention is a method for cleaning a spiral-wound membrane module comprising one or a plurality of spiral-wound membrane elements housed in a pressure vessel. Includes 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 raw liquid flow path material, and the outer peripheral portion of the spiral membrane element is liquid permeable. The outer peripheral surface side of the liquid-permeable material is entirely or partially covered with the outer peripheral channel material, and the pressure vessel has a plurality of liquid ports and at least one of the perforated hollow tubes. The cleaning liquid is introduced from the open end, and the cleaning liquid derived from the outer peripheral surface of the perforated hollow tube is discharged from at least the outer peripheral part of the spiral membrane element. Removed from the number of the liquid entrance to the outside,
An undiluted solution is supplied into the pressure vessel through another one of the plurality of liquid ports, and the undiluted liquid in the pressure vessel is taken out through any one of the above-described liquid ports or still another liquid port.

In the above-mentioned spiral membrane element of the spiral membrane module, since at least the outer peripheral portion is open without being covered with the exterior material, the stock solution is supplied from at least the outer peripheral side of the spiral membrane element. , Filtration can be performed. In this case, contaminants are trapped at least at the outer periphery of the spiral-wound membrane element.

At the time of washing, when the washing liquid is introduced from at least one open end of the perforated hollow tube, the washing liquid derived from the outer peripheral surface of the perforated hollow tube passes through the envelope-like membrane and flows along the undiluted liquid flow path material. And is discharged from at least the outer peripheral portion of the spiral membrane element. As a result, the contaminants trapped on the membrane surface and at least the outer peripheral portion of the spiral membrane element are separated from the spiral membrane element, and are discharged to the outside together with the cleaning liquid from one or more liquid ports of the pressure vessel. Therefore, the contaminants trapped on the membrane surface and at least the outer peripheral portion of the spiral membrane element can be uniformly removed.

Further, by introducing the undiluted solution into the pressure vessel and extracting the undiluted solution, a flow of the undiluted solution is formed in the axial direction along the outer peripheral portion of the spiral membrane element. As a result, the contaminants adhered to the membrane surface and at least the outer peripheral portion of the spiral membrane element can be easily and reliably peeled off, and the contaminants peeled from the spiral membrane element can be easily and reliably discharged to the outside. It is possible to perform more stable operation.

The stock solution is caused to flow in the axial direction along the outer peripheral portion of the spiral membrane element even before the washing solution is introduced from at least one opening end of the perforated hollow tube and backwashing is performed. Alternatively, it may be after performing backwashing. Alternatively, it may be performed simultaneously with the backwashing.

The cleaning liquid is a permeate, and at least a part of the permeate taken out of the pressure vessel and at least a part of the stock taken out of the pressure vessel may be returned to the stock supply side. In this case, it is possible to circulate at least a part of the permeate and the undiluted solution taken out of the pressure vessel, so that the permeate can be obtained at a higher recovery rate.

A spiral-type membrane module according to a fifth aspect of the present invention is a spiral-type membrane module in which one or a plurality of spiral-type membrane elements are housed in a pressure vessel. A plurality of envelope-like membranes independent or continuous on the outer peripheral surface of the tube include a spiral membrane element that is wound via a raw liquid flow path material, and the outer peripheral portion of the spiral membrane element is covered with a liquid permeable material, The outer peripheral surface side of the liquid-permeable material is wholly or partially covered with an outer peripheral channel material, the pressure vessel has one or more liquid ports, and one of the one or more liquid ports of the pressure vessel It is provided with a supply system for supplying the undiluted solution from at least the outer peripheral side of the spiral membrane element through one, and a take-out system for taking out the permeate from at least one open end of the perforated hollow tube. That.

In the spiral membrane module according to the present invention, the stock solution is supplied from at least the outer peripheral side of the spiral membrane element by the supply system, and the whole is filtered. In this case, since the contaminants are captured at least at the outer peripheral portion of the spiral membrane element, the load on the envelope membrane is reduced.

Further, since no dead space is formed in the gap between the spiral membrane element and the pressure vessel, liquid does not accumulate in the gap between the spiral membrane element and the pressure vessel. Therefore, even when used for separating a liquid containing an organic substance, problems such as propagation of microorganisms such as microorganisms, generation of offensive odor due to decomposition of the organic substance, and decomposition of the separation membrane do not occur, and high reliability can be obtained.

Further, the stock solution is supplied from at least the outer peripheral side of the spiral membrane element, and pressure is applied to the spiral membrane element from all directions, and no pressure that causes displacement in the axial direction is applied. The envelope-shaped membrane wound around the empty tube does not deform into a bamboo shoot. This eliminates the need for a packing holder and an exterior material, thereby reducing parts costs and manufacturing costs. Also, a high recovery rate can be obtained without using a large pump for supplying the stock solution. Thereby, the system cost is reduced.

Since pressure is applied to the spiral membrane element from all directions, the spiral membrane element does not deform even if the supply pressure of the stock solution is increased. Therefore, high pressure resistance can be obtained.

A spiral type membrane module according to a sixth aspect of the present invention is a spiral type membrane module in which one or a plurality of spiral type membrane elements are housed in a pressure vessel. A plurality of envelope-like membranes independent or continuous on the outer peripheral surface of the tube include a spiral membrane element that is wound via a raw liquid flow path material, and the outer peripheral portion of the spiral membrane element is covered with a liquid permeable material, The outer peripheral surface side of the liquid-permeable material is wholly or partially covered with the outer peripheral channel material, and the pressure vessel has a plurality of liquid ports,
A supply system for supplying a stock solution from at least the outer peripheral side of the spiral membrane element through any one of the plurality of liquid ports of the pressure vessel, and a permeate is taken out from at least one open end of the perforated hollow tube. A first withdrawal system, and a second withdrawal system that constantly or intermittently removes a part of the undiluted solution from another of the plurality of liquid ports to the outside of the pressure vessel.

In the spiral membrane module according to the present invention, the stock solution is supplied from at least the outer peripheral side of the spiral membrane element by the supply system, and filtration is performed. In this case, since the contaminants are captured at least at the outer peripheral portion of the spiral membrane element, the load on the envelope membrane is reduced.

Further, a part of the stock solution supplied by the supply system is taken out of the pressure vessel by the second take-out system.
It is possible to always or intermittently form the flow of the stock solution in the axial direction. Such a flow of the stock solution makes it possible to suppress contaminants in the stock solution from adhering to at least the outer peripheral portion of the spiral membrane element. Thereby, stable operation can be performed for a long period of time.

Further, since no dead space is formed in the gap between the spiral membrane element and the pressure vessel, liquid does not accumulate in the gap between the spiral membrane element and the pressure vessel. Therefore, even when used for separating a liquid containing an organic substance, problems such as propagation of microorganisms such as microorganisms, generation of offensive odor due to decomposition of the organic substance, and decomposition of the separation membrane do not occur, and high reliability can be obtained.

Further, the stock solution is supplied from at least the outer peripheral side of the spiral type membrane element, and pressure is applied to the spiral type membrane element from all directions and no pressure which causes displacement in the axial direction is applied. The envelope-shaped membrane wound around the empty tube does not deform into a bamboo shoot. This eliminates the need for a packing holder and an exterior material, thereby reducing parts costs and manufacturing costs. Also, a high recovery rate can be obtained without using a large pump for supplying the stock solution. Thereby, the system cost is reduced.

Since pressure is applied to the spiral membrane element from all directions, the spiral membrane element does not deform even if the supply pressure of the stock solution is increased. Therefore, high pressure resistance can be obtained.

A circulation system for returning at least a part of the undiluted solution taken out of the pressure vessel to the supply side may be further provided. In this case, at least a part of the undiluted solution taken out can be circulated by the circulating system, so that the permeate can be obtained at a high recovery rate.

A spiral-type membrane module according to a seventh aspect of the present invention is a spiral-type membrane module in which one or a plurality of spiral-type membrane elements are housed in a pressure vessel. A plurality of envelope-like membranes independent or continuous on the outer peripheral surface of the tube include a spiral membrane element that is wound via a raw liquid flow path material, and the outer peripheral portion of the spiral membrane element is covered with a liquid permeable material, The outer peripheral surface side of the liquid-permeable material is wholly or partially covered with the outer peripheral channel material, the pressure vessel has one or more liquid ports, and the cleaning liquid is supplied from at least one open end of the perforated hollow tube. And a cleaning liquid derived from the outer peripheral surface of the perforated hollow tube is discharged from at least the outer peripheral portion of the spiral membrane element, and is taken out through one or more liquid ports of the pressure vessel. It is obtained by a extraction system.

In the spiral membrane element of the spiral membrane module described above, since at least the outer peripheral portion is open without being covered with the outer material, the stock solution is supplied from at least the outer peripheral side of the spiral membrane element. , Filtration can be performed. In this case, contaminants are trapped at least at the outer periphery of the spiral-wound membrane element.

In such a spiral type membrane module, at the time of washing, a washing solution is introduced from at least one open end of the perforated hollow tube by an introduction system. The cleaning liquid derived from the outer peripheral surface of the perforated hollow tube passes through the envelope-like membrane, flows along the raw liquid flow path material, and is discharged from at least the outer peripheral portion of the spiral membrane element. Thereby, the contaminants trapped on the membrane surface and at least the outer peripheral portion of the spiral membrane element are separated from the spiral membrane element,
It is taken out from the liquid inlet and outlet together with the cleaning liquid and discharged to the outside of the pressure vessel through the system. Therefore, the contaminants trapped on the membrane surface and at least the outer peripheral portion of the spiral membrane element can be uniformly removed.

The cleaning liquid is a permeate, and may further include a circulation system for returning at least a part of the permeate taken out of the pressure vessel to the stock solution supply side. In this case, at least a part of the permeate taken out can be circulated by the circulation system, so that the permeate can be obtained at a high recovery rate.

The spiral membrane module according to the eighth invention is a spiral membrane module in which one or a plurality of spiral membrane elements are housed in a pressure vessel, wherein the spiral membrane element has a perforated hollow. A plurality of envelope-like membranes independent or continuous on the outer peripheral surface of the tube include a spiral membrane element that is wound via a raw liquid flow path material, and the outer peripheral portion of the spiral membrane element is covered with a liquid permeable material, The outer peripheral surface side of the liquid-permeable material is wholly or partially covered with the outer peripheral channel material, and the pressure vessel has a plurality of liquid ports,
An introduction system for introducing a cleaning liquid from at least one open end of the perforated hollow tube, and a cleaning liquid derived from the outer peripheral surface of the perforated hollow tube discharged from at least the outer peripheral portion of the spiral membrane element; One of the liquid ports
Alternatively, a first take-out system that takes out the liquid from the plurality of liquid ports, a supply system that supplies the stock solution into the pressure vessel through another one of the plurality of liquid ports, A second take-out system for taking out to the outside through one of the liquid ports or a further liquid port.

In the spiral-type membrane element of the spiral-type membrane module, since at least the outer peripheral portion is open without being covered with the exterior material, the stock solution is supplied from at least the outer peripheral portion side of the spiral-type membrane element. , Filtration can be performed. In this case, contaminants are trapped at least at the outer periphery of the spiral-wound membrane element.

In such a spiral type membrane module, at the time of washing, a washing solution is introduced from at least one open end of the perforated hollow tube by an introduction system. The cleaning liquid derived from the outer peripheral surface of the perforated hollow tube passes through the envelope-like membrane, flows along the raw liquid flow path material, and is discharged from at least the outer peripheral portion of the spiral membrane element. Thereby, the contaminants captured on at least the membrane surface and the outer peripheral portion of the spiral membrane element are separated from the spiral membrane element,
Along with the cleaning liquid, the liquid is discharged to the outside of the pressure vessel through one or more liquid ports through a first removal system. Therefore, the contaminants trapped on the membrane surface and at least the outer peripheral portion of the spiral membrane element can be uniformly removed.

Further, since a supply system for supplying the undiluted solution and a second withdrawing system for extracting the undiluted solution are provided,
The flow of the stock solution can be formed in the axial direction along the outer peripheral portion of the spiral membrane element. As a result, the contaminants adhered to the membrane surface and at least the outer peripheral portion of the spiral membrane element can be easily and reliably peeled off, and the contaminants peeled from the spiral membrane element can be easily and reliably discharged to the outside. Therefore, more stable operation can be performed. Note that the flow of the stock solution in the axial direction along the outer peripheral portion of the spiral membrane element may be performed before the backflow cleaning by introducing the cleaning solution from at least one open end of the perforated hollow tube, Alternatively, after the backwashing is performed.
Alternatively, it may be performed simultaneously with the backwashing.

The washing liquid is a permeate, and further comprises a circulation system for returning at least a part of the permeate taken out of the pressure vessel and at least a part of the stock taken out of the pressure vessel to the stock supply side. Is also good. In this case, at least a part of the permeate and the undiluted solution taken out of the pressure vessel can be circulated by the circulation system, so that the permeate can be obtained at a higher recovery rate.

[0065]

FIG. 1 is a partially cutaway perspective view of a spiral membrane element according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing an example of the envelope-shaped membrane of the spiral membrane element shown in FIG. 1, and FIG. 3 is a cross-sectional view showing another example of the envelope-shaped membrane of the spiral membrane element shown in FIG. is there.

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. . Raw water spacers (raw liquid flow path material) between the envelope films 3 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.
4 has been inserted.

The outer peripheral surface of the spiral membrane element 1a is covered with a separation membrane 9 which is a liquid permeable material. As the separation membrane 9, a microfiltration membrane or an ultrafiltration membrane is used.

As the microfiltration membrane, a polymer organic membrane such as polyolefin, polysulfone, polypropylene, polyethylene, polystyrene, polyacrylonitrile, cellulose acetate and the like can be used. As the ultrafiltration membrane, polysulfone, polypropylene, polystyrene,
A high molecular organic film such as polyacrylonitrile, cellulose acetate, or polyethylene can be used.

The outer peripheral surface of the separation membrane 9 is covered with an outer peripheral channel material 5 made of a net. As the material of the net,
Polymer materials such as polyolefin, polysulfone, polypropylene, polyethylene, polystyrene, polyacrylonitrile, and cellulose acetate; inorganic materials such as ceramic;
Metal, synthetic rubber, fiber, or the like can be used.

The pore size of the microfiltration membrane is 0.01 μm or more and 1
It is preferably 0 μm or less. The pore size of the ultrafiltration membrane is preferably from 20,000 to 0.01 μm. Further, it is preferable that the net used as the outer peripheral channel material 5 has a mesh size of 4 mesh or more and 100 mesh or less.

The pore size of the microfiltration membrane or the ultrafiltration membrane used as the separation membrane 9 and the number of meshes of the net used as the outer peripheral passage material 5 are selected according to the quality of the raw water.

In the spiral membrane element 1 shown in FIG. 1, a microfiltration membrane having a pore diameter of 0.4 μm and made of polyolefin such as ethylene vinyl alcohol is used as the separation membrane 9. Further, an ultrafiltration membrane made of polysulfone may be used as the separation membrane 9. Further, a 50 mesh net made of PET (polyethylene terephthalate) is used as the outer peripheral channel material 5.

Note that, in addition to the outer peripheral surface of the spiral membrane element 1a, the end face of the spiral membrane element 1a may be covered with the separation membrane 9.

As shown in FIG. 2 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. 2, 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 likely to come into contact with each other, and the film area is reduced. Therefore,
The thickness of the raw water spacer 4 is preferably 0.1 mm or more and 0.5 mm or less.

As shown in FIG. 1, the outer peripheral flow path member 5 is formed in a lattice shape such that a plurality of wires 61 and 62 cross each other at right angles. The thickness of the wire 61 is set to be larger than the thickness of the wire 62. This makes it easier for the raw water 51 to flow between the wires 61 almost linearly in a direction parallel to the wires 61.

Further, as shown in FIG.
Are arranged such that the wire 61 is parallel to the axial direction of the water collecting pipe 2. Therefore, the raw water is the spiral membrane element 1
It becomes easy to flow in the axial direction at the outer peripheral portion of a.

When the thickness t of the outer peripheral flow path member 5 is larger than 30 mm, the volume efficiency of the spiral membrane element 1 with respect to the pressure vessel containing the spiral membrane element 1 is reduced. On the other hand, the thickness t of the outer peripheral channel material 5 is 0.6 m.
If it is smaller than m, the flow rate of raw water for discharging contaminants attached to at least the outer peripheral portion of the spiral membrane element 1 during backflow cleaning of permeated water is reduced. Therefore, the thickness of the outer peripheral channel material 5 is 0.6 mm or more and 30 m or more.
m or less.

The porosity in the thickness direction of the outer peripheral flow path member 5 is set to, for example, 20% or more and 60% or less. Thereby, sufficient strength of the outer peripheral channel member 5 can be secured while reducing the resistance of the raw water that moves the contaminant in the axial direction during the backwashing. The vertical and horizontal pitches of the mesh of the outer peripheral channel member 5 are, for example, 3 mm or more and 30 mm or less.
Thus, the raw water can be sufficiently supplied between the envelope-shaped membranes 3 while preventing the outer peripheral surface of the spiral membrane element 1a from contacting the pressure vessel and narrowing the flow path of the raw water.

The whole of the outer peripheral separation membrane 9 may be covered with the outer peripheral channel material 5, or a part of the region may be covered with the outer peripheral channel material 5.

FIG. 4 is a sectional view showing an example of an operation method of the spiral membrane module according to the present invention. As shown in FIG. 4, a pressure vessel (pressure-resistant vessel) 10 of a spiral-type membrane module includes a cylindrical case 11 and a pair of end plates 12a,
12b. A raw water inlet 13 is formed at one end of the bottom of the cylindrical case 11. A permeated water outlet 14 is provided at the center of both end plates 12a and 12b.

The spiral type membrane element 1 shown in FIG. 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. Both ends of the water collecting pipe 2 are an end plate 12a and an end plate 12b, respectively.
To the permeated water outlet 14. Thus, a spiral-type membrane module in which one spiral-type membrane element 1 is loaded in the pressure vessel 10 is configured.

The raw water inlet 13 at the bottom of the cylindrical case 11
A pipe 19 is connected. The piping 19 is a pressurized pump 1
01 is connected to the raw water tank 100, and the pipe 19 is further connected to a pipe 20. The pipes 19 and 20 have valves 18a, 1 respectively.
8b are provided.

During operation of the spiral membrane element 1, the valve 18a of the pipe 19 is opened and the valve 18b of the pipe 20 is closed. Raw water 5 from raw water tank 100
1 is pressurized by a pressure pump 101 and introduced into the pressure vessel 10 from a raw water inlet 13 of the pressure vessel 10 through a pipe 19. The raw water 51 flows along the outer peripheral channel material 5,
The envelope-shaped membrane 3 penetrates the separation membrane 9 from at least the outer peripheral side of the spiral-type membrane element 1, and follows the raw water spacer 4.
Penetrate in between. In the example of FIG. 4, 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 52 is taken out from the permeated water outlets 14 at both ends of the pressure vessel 10. In this way, total filtration is performed.

In this example, the valve 18a and the pipe 19 correspond to a supply system, and the pipe (not shown) connected to the permeate outlet 14 corresponds to a take-out system.

In this case, since the outer peripheral surface of the spiral membrane element 1 a is covered with the separation membrane 9, contaminants such as turbid substances larger than the pore diameter of the separation membrane 9 are removed from at least the outer periphery of the spiral membrane element 1. Caught in the department. That is,
Only contaminants smaller than the pore size of the separation membrane 9
Break in. Therefore, the load on the separation membrane 7 constituting the envelope-shaped membrane 3 is reduced.

After filtration for a certain period of time, backwashing with permeated water 52a is performed from the permeate side. FIG. 5 is a partially cutaway perspective view showing a cleaning operation of the spiral membrane element 1 of FIG. At the time of backwashing, the valve 18 of the pipe 19 is
With the valve a closed and the valve 18b of the pipe 20 opened, the permeated water 52a is introduced into the water collecting pipe 2 from the permeated water outlet 14 in FIG. The permeated water 52a at the time of backwashing passes through the envelope-shaped membrane 3 from the water collecting pipe 2 to separate contaminants adhered to the membrane surface, the raw water spacer 4, and the like, and flows along the raw water spacer 4 at least to the outer peripheral portion. . The permeated water 52
Due to a, the contaminants trapped on at least the outer peripheral portion of the spiral membrane element 1 are easily separated. The separated contaminants are mixed with the permeated water 52a together with the raw water inlet 13 shown in FIG.
And discharged through the pipe 20 to the outside.

In this example, a pipe (not shown) connected to the permeate outlet corresponds to the introduction system, and the valve 18b and the pipes 19 and 20 correspond to the take-out system.

According to the above-described cleaning method, the contaminants adhering to the outer peripheral portion of the spiral membrane element 1, the raw water spacer 4, the membrane surface, etc., particularly, to the separation membrane 9, can be easily separated, and the separated contaminants can be removed from the outer periphery. Since it can be easily discharged to the outside along the partial flow path member 5, an increase in the resistance of the separation membrane 9 can be suppressed. Thereby, a stable amount of permeated water can be maintained. Further, since the outer peripheral portion is covered with the outer peripheral portion flow path member 5, the handling of the spiral membrane element 1 is improved.

Further, since the dead space such as the dead space S shown in FIG. 20 is not formed in the space between the spiral membrane element 1 and the pressure vessel 10 by the above-mentioned filtration mode, various bacteria such as microorganisms can be formed. There is no problem of odor propagation, generation of offensive odor due to decomposition of organic matter, decomposition of separation membrane, etc., and high reliability can be obtained.

Further, since pressure is applied to the spiral membrane element 1 from all directions, the spiral membrane element 1
No deformation problem occurs, and the packing holder and the exterior material become unnecessary. Thereby, component costs and manufacturing costs are reduced.

[0093] Since the whole amount is filtered, the raw water 51
It is not necessary to use a large pump for supplying pressure. Thereby, the system cost is reduced.

At the time of washing, part or all of the permeated water 52a discharged to the outside through the pipe 20 may be returned to the raw water tank 100 again. In this case,
This will be described below.

FIG. 6 is a sectional view showing another example of the method of operating the spiral membrane module according to the present invention. The spiral membrane module shown in FIG. 6 has the same configuration as the spiral membrane module shown in FIG. 4 except for the following points.

As shown in FIG.
A pipe 21 is further connected upstream of b. The pipe 21 is provided with a valve 18e.

In this example, during operation, the valve 18a of the pipe 19 is opened, and the valve 18b of the pipe 20 and the valve 18e of the pipe 21 are closed. In this case, total filtration is performed by a method similar to the method of operating the spiral-wound membrane module shown in FIG.

At the time of cleaning, the valve 18 of the pipe 20 is
b and the valve 18e of the pipe 21 are opened, and the valve 18a of the pipe 19 is closed. In this case, backwashing is performed in the same manner as in the case of washing the spiral membrane module shown in FIG. 5, and the permeated water 52a used for backwashing is supplied to the raw water inlet 1.
3 is taken out of the pressure vessel 10. The permeated water 52a is guided to the pipe 20 via the pipe 19. further,
In this example, since the valve 18e of the pipe 21 is open, a part of the permeated water 52a is guided from the pipe 20 to the pipe 21 and returned to the raw water tank 100 through the pipe 21. On the other hand, the remaining permeated water 52a is discharged through the pipe 20.

In this embodiment, the pipes 19, 20, 21 and the valve 18e correspond to a circulation system.

According to the operation method of the spiral membrane module described above, the same effects as those described above in the operation method of the spiral membrane module shown in FIG. 4 can be obtained during operation and cleaning. Furthermore, at the time of washing, the permeated water 52a used for backwashing can be collected in the raw water tank 100 and supplied again as the raw water 51, so that the permeated water 52 can be obtained from the spiral membrane module at a high recovery rate. It becomes possible.

At the time of washing, the valve 18b of the pipe 20 may be fully closed, and all the permeated water 52a used for backwashing may be returned to the raw water tank 100.

In the spiral membrane module shown in FIGS. 4 and 6, the case where the raw water inlet 13 is provided at one end of the bottom of the cylindrical case 11 has been described, but the position of the raw water inlet 13 is not limited to this. is not. For example, the raw water inlet 13 may be provided at one end of the upper part of the cylindrical case 11, or may be provided at the center of the upper part or the bottom part of the cylindrical case 11. Further, the raw water inlet 13 may be provided in the end plate 12a or the end plate 12b.

In the operation method of the spiral-wound membrane module shown in FIGS. 4 and 6, the case where the entire amount is filtered during the operation and the backwashing is performed during the washing has been described. The part may be taken out of the pressure vessel 10. At the time of washing, flushing with raw water may be performed. In these cases,
This will be described below.

FIG. 7 is a sectional view showing still another example of the method of operating the spiral membrane module according to the present invention. The spiral membrane module shown in FIG. 7 has the same configuration as the spiral membrane module shown in FIG. 4 except for the following points.

In the spiral type membrane module shown in FIG. 7, a raw water outlet 15 is provided at one end of the upper part of the cylindrical case 11 of the pressure vessel 10. A pipe 17 is connected to the raw water outlet 15. Also, a pipe 18 has a valve 18.
c is provided. The raw water outlet 15 is also used as an air vent.

In this example, during operation, the valve 18a of the pipe 19 and the valve 18c of the pipe 17 are opened, and the valve 18b of the pipe 20 is closed. In this case, in the same manner as in the operation of the spiral type membrane module shown in FIG.
Introduced within.

Here, in this embodiment, a part of the introduced raw water 51 flows in the axial direction along the outer periphery of the spiral membrane element 1, and the raw water 51 a flows from the raw water outlet 15 of the pressure vessel 10 to the pipe 17. Discharged to the outside. On the other hand, the remaining raw water flows along the outer peripheral flow path member 5 as in the operation of the spiral membrane module shown in FIG. 4, and the envelope membrane 3 flows from the outer peripheral side and both end sides of the spiral membrane element 1. Penetrate in between. 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 52 is taken out from the permeated water outlet 14 of the pressure vessel 10.

In this example, the valve 18a and the pipe 19 correspond to the supply system, the pipe (not shown) connected to the permeate outlet corresponds to the first extraction system, and the pipe 17 and the valve 18c correspond to the second extraction system. Equivalent to the take-out system.

In this example, since the flow of the raw water 51a is formed in the axial direction along the outer peripheral portion of the spiral membrane element 1, a part of the contaminants is suppressed while the sediment of the contaminants in the raw water is suppressed. It can be discharged to the outside of the pressure vessel 10 together with the raw water 51a.

During the operation of the above spiral type membrane module, the valve 18c of the pipe 17 may be always opened or may be opened intermittently. When the valve 18c is opened intermittently, the amount of the raw water 51a discharged from the raw water outlet 15 to the outside is suppressed, so that the recovery rate of the permeated water 52 is higher than when the valve 18c is always opened.

In this example, the valve 18a and the pipe 19 correspond to the supply system, the pipe (not shown) connected to the permeate outlet corresponds to the first extraction system, and the pipe 17 and the valve 18c correspond to the second extraction system. Equivalent to the take-out system.

On the other hand, at the time of cleaning,
a is closed, the valve 18b of the pipe 20 and the valve 18c of the pipe 17 are opened, and backflow cleaning is performed in the same manner as the spiral membrane module cleaning method shown in FIG. In this case, the permeated water 52a used for backwashing is:
The raw water is discharged from the raw water inlet 13 and the raw water outlet 15 through the pipes 17 and 20 to the outside.

In this example, a pipe (not shown) connected to the permeated water outlet corresponds to an introduction system, and the pipe 17 and the valve 18c correspond to an extraction system.

As described above, in this example, the pressure vessel 1
Since the permeated water 52a is discharged from the raw water inlet 13 and the raw water outlet 15 at both ends of the spiral-type membrane element 1, the contaminants trapped on the membrane surface, the outer peripheral portion, and the like of the spiral membrane element 1 are efficiently separated by backwashing, and Can be discharged to In addition, the startup of the spiral-wound membrane module at the time of resuming operation is quickened.

According to the above-described cleaning method, the contaminants adhering to the outer peripheral portion of the spiral membrane element 1, the raw water spacer 4, the membrane surface, etc., particularly the contaminants adhering to the separation membrane 9, can be easily removed. Since it can be easily discharged to the outside along the path member 5, an increase in the resistance of the separation membrane 9 can be suppressed. Thereby, a stable amount of permeated water can always be maintained.

As in the present example, in the operation method of the spiral membrane module for taking out a part of the raw water 51a out of the supplied raw water 51, the space between the spiral membrane element 1 and the pressure vessel 10 is also reduced. No dead space is formed. Therefore, problems such as propagation of various germs such as microorganisms, generation of offensive odor due to decomposition of organic matter, and decomposition of the separation membrane do not occur, and high reliability can be obtained.

Further, since pressure is applied to the spiral membrane element 1 from all directions, the spiral membrane element 1
No deformation problem occurs, and the packing holder and the exterior material become unnecessary. Thereby, component costs and manufacturing costs are reduced.

The pressurizing pump 10 for supplying raw water 51
It is not necessary to use a large one, and the system cost is reduced.

In the above-mentioned method of operating the spiral membrane module, flushing with raw water may be performed at the time of washing. For example, after performing the above-described backwashing, the valve 18a of the pipe 19 is opened and the pipe 20 is opened.
While the valve 18b is closed, the valve 18c of the pipe 17 is opened while the raw water 51b is supplied from the raw water inlet 13 through the pipe 19. Thereby, the supplied raw water 51b
Flows linearly in the axial direction along the outer peripheral flow path member 5, and flushing is performed.

In this example, the pipe 17 and the valve 18c correspond to the first and second extraction systems.

In the example of FIG. 7, the permeated water 52a used for backwashing and the raw water 51b used for flushing are taken out from the same raw water outlet 15, but when the pressure vessel 11 has another outlet, Alternatively, the permeated water 52a used for backwashing and the raw water 51b used for flushing may be taken out from separate outlets.

FIG. 8 is a partially cutaway perspective view showing the operation of backwashing and flushing at the time of cleaning the spiral membrane element 1 of FIG. As shown in FIG. 8, the contaminants separated from the spiral membrane element 1 by the backwashing are flushed to remove the raw water outlet 15 shown in FIG.
The water is easily and reliably discharged to the outside together with the raw water 51b through the pipe 17. In addition, by the flushing, the contaminants remaining on the outer peripheral portion of the spiral membrane element 1, the raw water spacer 4, the membrane surface, and the like without being separated by the backwashing are easily and reliably separated, and are passed through the pipe 17 from the raw water outlet 15. It is discharged outside. As a result of the backwashing and flushing as described above, the membrane flux is remarkably recovered as compared to before the washing, and a more reliable and stable operation can be performed.

In the above-mentioned cleaning method, the contaminants trapped on the outer peripheral portion of the spiral membrane element 1 and the like are separated by backwashing, and then flushing with the raw water 51b is performed. After that, backwashing may be performed. In this case, most of the contaminants trapped on the membrane surface, the outer peripheral portion, etc. of the spiral membrane element 1 are removed by flushing,
Further, contaminants remaining on the outer peripheral portion of the spiral membrane element 1 and the like can be removed by backwashing.
Alternatively, flushing with the raw water 51b may be performed simultaneously with the backwashing. In this case, the same effect as above can be obtained.

Further, in the above-described operation method of the spiral membrane module, a part of the raw water 51a taken out during operation may be circulated and returned to the raw water tank 100 again. This case will be described below.

FIG. 9 is a sectional view showing still another example of the spiral membrane module according to the present invention. The spiral membrane module shown in FIG. 9 has the same configuration as the spiral membrane module shown in FIG. 7 except for the following points.

A pipe 17a is further connected to the pipe 17 upstream of the valve 18c. Further, a pipe 21 is further connected to the pipe 20 on the upstream side of the valve 18b. The pipe 17a and the pipe 21 are provided with a valve 18d and a valve 18b, respectively, and the pipe 17a and the pipe 21 are connected to the raw water tank 100.

In this example, during operation, the valve 18a of the pipe 19 and the valve 18d of the pipe 17a are opened, and the valve 18b of the pipe 20, the valve 18e of the pipe 21, and the pipe 1 are opened.
7 is closed by the valve 18c. In this case, raw water 51 is introduced into the pressure vessel 10 from the raw water inlet 13 of the pressure vessel 10 through the pipe 19 in the same manner as in the spiral type membrane module shown in FIG. Of the raw water 51 introduced into the pressure vessel 10, a part of the raw water 51a flows in the axial direction along the outer peripheral portion of the spiral membrane element 1. Here, in this example, since the valve 18d of the pipe 17a is open, a part of the raw water 51a is taken out from the raw water outlet 15 of the pressure vessel 10 and then returned to the raw water tank 100 through the pipe 17a. It is. On the other hand, the remaining raw water is filtered by the spiral membrane element 1 and taken out as permeated water 52 from the permeated water outlet 14 of the pressure vessel 10.

In this example, the pipe 17a and the valve 18d
Corresponds to the circulatory system.

In this example, since the flow of the raw water 51a is formed in the axial direction along the outer peripheral portion of the spiral membrane element 1, it is possible to suppress the sedimentation of contaminants in the raw water. In addition, since the raw water 51a taken out from the raw water outlet 15 is circulated, the permeated water 52 can be obtained at a higher recovery rate.

During the operation of the above spiral type membrane module, the valve 18d of the pipe 17a may be always opened or may be opened intermittently. Thereby, the flow of the raw water 51a can be always or intermittently formed in the axial direction along the outer peripheral portion of the spiral membrane element 1.

Further, the valve 18c of the pipe 17 may be opened. Thereby, a part of the raw water 51a taken out from the raw water outlet 15 can be discharged outside through the pipe 17, and the remaining raw water 51a can be returned to the raw water tank 100. In this case, a part of the pollutants can be discharged to the outside of the pressure vessel 10 together with the raw water 51a.

On the other hand, at the time of cleaning,
a, valve 18b of pipe 20 and valve 1 of pipe 17
8c is closed, the valve 18d of the pipe 17a and the valve 18e of the pipe 21 are opened, and backflow cleaning is performed in the same manner as the spiral membrane module shown in FIG. In this case, the permeated water 5 used for backwashing was used.
2a is taken out from the raw water inlet 13 and the raw water outlet 15, and then returned to the raw water tank 100 again through the pipe 21 and the pipe 17a.

In this example, the pipe 17a and the valve 18d
Corresponds to the circulatory system.

As described above, in this example, the pressure vessel 1
Since the permeated water 52a can be taken out from the raw water inlet 13 and the raw water outlet 15 at both ends of the spiral membrane element 1, contaminants trapped on the membrane surface, the outer peripheral portion, etc. of the spiral membrane element 1 can be efficiently removed by backwashing. As a result, it is possible to discharge the pressure to the outside of the pressure vessel 10, and the spiral-type membrane module rises quickly when the operation is restarted. Further, since the permeated water 52a used for the backwashing can be recovered in the raw water tank 100 and supplied again as the raw water 51, the permeated water 52 can be obtained at a high recovery rate.

As described above, according to the operation method of the spiral membrane module shown in this example, the same effects as those described above in the operation method of the spiral membrane module shown in FIG. Is obtained. further,
In this example, since the raw water 51a and the permeated water 52a taken out are returned to the raw water tank 100, the permeated water 52 can be obtained at a high recovery rate.

In the above-described method of operating the spiral membrane module, flushing with raw water may be performed at the time of cleaning. In this case, for example, after performing the above-mentioned backwashing, the raw water 51b is supplied from the raw water inlet 13 through the pipe 19 with the valve 18a of the pipe 19 opened, the valve 18b of the pipe 20 and the valve 18e of the pipe 21 closed. . In this case, the raw water 51b used for flushing
Is returned to the raw water tank 100 through the pipe 17a.
By such backwashing and flushing, contaminants can be easily and reliably peeled off and discharged to the outside. As a result, the membrane flux of the spiral type membrane module is remarkably recovered as compared with before the washing, and a more reliable and stable operation can be performed.

Although flushing is performed after backwashing in the above description, flushing may be performed before backwashing or may be performed simultaneously with backwashing. In these cases, the same effects as above can be obtained.

At the time of cleaning, the valve 18b of the pipe 20 and the valve 18c of the pipe 17 are opened, and a part of the permeated water 52a used for the backwashing or a part of the raw water 51b used for the flushing is supplied to the pipe 20 and the pipe. It may be discharged to the outside through 17. In this case, the separated contaminants can be discharged to the outside together with the permeated water 52a or the raw water 51b through the pipes 17 and 20.

In the spiral type membrane module shown in FIGS. 7 and 9, the case where the raw water inlet 13 and the raw water outlet 15 are provided at both ends of the pressure vessel has been described. It is not limited.

In the spiral-type membrane module shown in FIGS. 4 to 9, one spiral-type membrane element 1 is loaded in the pressure vessel 10, but the spiral-type membrane module operating method according to the present invention is used. Can be applied to a spiral membrane module in which a plurality of spiral membrane elements 1 are loaded. An operation method of such a spiral membrane module will be described below.

FIG. 10 is a sectional view showing still another example of the operation method of the spiral membrane module according to the present invention.
The operation method of the spiral membrane module shown in FIG.
Except for the following points, it is the same as the operation method of the spiral membrane module shown in FIG.

As shown in FIG. 10, the pressure vessel 100
A cylindrical case 111 and a pair of end plates 120a, 120b
It consists of. A raw water inlet 130 is formed at the bottom of the cylindrical case 111, and an air vent (not shown) is provided at the top. Also, the end plates 120a, 120b
Is provided with a permeated water outlet 140 at the center.

A plurality of spiral membrane elements 1 in which the water collecting pipes 2 are connected in series by an interconnector 116 are housed in a cylindrical case 111, and both open ends of the cylindrical case 111 are connected to end plates 120a and 120b, respectively. Sealed. Water collecting pipe 2 of spiral type membrane element 1 at both ends
Are connected to the end plates 12 through the adapter 115, respectively.
0a and 120b are fitted to the permeated water outlet 140. Thus, a spiral-type membrane module in which the plurality of spiral-type membrane elements 1 are loaded in the pressure vessel 100 is configured.

During the operation of the above spiral type membrane module, the raw water inlet 13 of the pressure vessel 100 is
From 0, raw water 51 is introduced into the pressure vessel 100. The raw water 51 flows along the outer peripheral channel material 5 of each spiral membrane element 1. In each spiral membrane element 1, the raw water 51 penetrates the separation membrane 9 at least from the outer peripheral side, and penetrates between the envelope-shaped membranes 3 along the raw water spacer 4. The permeated water 52 that has passed through the separation membrane 7 is
Flows into the inside of the water collecting pipe 2 along the line, and is taken out from the permeated water outlet 140 at both ends of the pressure vessel 100.

After filtration for a certain period of time, backwashing with permeated water 52a is performed from the permeate side. In the backwashing, permeated water 52a is introduced into the water collecting pipe 2 of the spiral membrane element 1 from the permeated water outlets 140 at both ends of the pressure vessel 100. In each spiral type membrane element 1, permeated water 5
2a penetrates the envelope-shaped membrane 3 from the water collecting pipe 2 to separate contaminants on the membrane surface from the membrane surface, and flows along the raw water spacer 4 at least toward the outer peripheral portion. The permeated water 52a
As a result, the contaminants captured on at least the outer peripheral portion of each spiral membrane element 1 are easily separated. The separated contaminants are discharged to the outside through the pipe 20 from the raw water inlet 130 together with the permeated water 52a.

According to the operation method of the spiral-type membrane module as described above, like the operation method of the spiral-type membrane module shown in FIG. The spiral membrane element 1 is supplied and subjected to total filtration in each spiral type membrane element 1. In this case, in each spiral type membrane element 1, the contaminants in the raw water 51 are captured at least at the outer peripheral portion. Therefore, the separation membrane 7 constituting the envelope membrane 3
Load is reduced.

Further, at the time of cleaning, contaminants adhering to the membrane surface of each spiral type membrane element 1, the raw water spacer 4, the outer peripheral portion and the like are easily peeled off, and the outer peripheral flow path material 5 is removed.
Can be easily discharged to the outside along the line, so that a stable amount of permeated water can be maintained.

Further, since the spiral-type membrane module is loaded with a plurality of spiral-type membrane elements 1, the processing capacity of the spiral-type membrane module is large, and the permeated water 52 can be obtained efficiently.

Further, since the dead space is not formed in the space between each spiral type membrane element 1 and the pressure vessel 100 by the above-mentioned filtration form, the propagation of various germs such as microorganisms and the odor caused by the decomposition of organic substances are eliminated. No problems such as generation and decomposition of the separation membrane occur, and high reliability can be obtained.

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

Further, since the whole amount is filtered, the raw water 51
It is not necessary to use a large pump for supplying pressure. Thereby, the system cost is reduced.

In the above description, the case where the spiral membrane module operating method shown in FIG. 4 is applied to a spiral membrane module in which a plurality of spiral membrane elements 1 are loaded in a pressure vessel 100 has been described.
6 to 9 can be applied to a spiral-type membrane module in which a plurality of spiral-type membrane elements 1 are loaded.

Although the spiral type membrane modules shown in FIGS. 4 to 10 are installed horizontally, the installation method of the spiral type membrane module is not limited to the horizontal installation. For example, a vertical installation in which the spiral type membrane module is installed vertically, or an inclined installation in which the spiral membrane module is installed in an inclined manner may be used. Note that an installation method capable of efficiently removing contaminants attached to the membrane surface, the outer peripheral portion, and the like of the spiral membrane element 1 is preferable.

Further, in the spiral type membrane module shown in FIGS. 4 to 10, both ends of the water collecting pipe 2 are open, and the water outlets 14 and 140 provided at both ends of the pressure vessels 10 and 100 are connected to each other. Although the permeated water 52 is taken out, one end of the water collecting pipe 2 may be sealed. In this case, for example, a permeated water outlet is provided on one end plate of the pressure vessel, and an open end of the water collecting pipe 2 is fitted to the permeated water outlet.

The spiral membrane element in the spiral membrane module according to the present invention as shown in FIGS. 4 to 10 is different from the spiral membrane element shown in FIG.
The following spiral-type membrane element may be used.

FIG. 11 is a front view of a spiral membrane element according to another embodiment of the present invention. In FIG. 11, the illustration of the outer peripheral channel material is omitted.

In the spiral membrane element 1 shown in FIG. 11A, both ends of the spiral membrane element 1a are sealed with a resin layer 40. In the spiral membrane element 1 shown in FIG. 11B, one end of the spiral membrane element 1 a is sealed with a resin layer 40.

In the spiral membrane element 1 shown in FIGS. 11 (a) and 11 (b), the number of working steps at the time of manufacturing is increased, but a space for supplying raw water to both ends or one end of the spiral membrane element 1 is not required. Become. Therefore, the pressure vessel can be miniaturized, and the spiral membrane module in which the spiral membrane element 1 is housed in the pressure vessel can be miniaturized.

Further, by disposing the end of the spiral membrane element 1 sealed with the resin layer 40 on the raw water inlet side of the pressure vessel, the end surface of the spiral membrane element 1 is moved by the dynamic pressure of the raw water when the raw water is introduced. Dirt can be prevented from adhering.

FIG. 12 is a partially cutaway perspective view of a spiral type membrane element according to still another embodiment of the present invention. FIG. 13 is a cross-sectional view showing an example of an envelope-shaped membrane of the spiral membrane element shown in FIG. 12, and FIG.
It is a cross-sectional view which shows the other example of the envelope-shaped membrane of 2 spiral-type membrane elements. FIG. 15 is a partially cutaway front view of the spiral membrane element of FIG.

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. . Raw water spacers (raw liquid flow path material) between the envelope films 3 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.
4 has been inserted.

As shown in FIGS. 13 and 14, the envelope-shaped membrane 3 is provided on both sides of a permeated water spacer (permeated liquid channel material) 6.
The separation membrane 7 is formed by overlapping and bonding three sides, and the opening of the envelope-shaped membrane 3 is attached to the outer peripheral surface of the water collecting pipe 2. 10 kgf for the separation membrane 7
/ Cm pressure reverse osmosis membrane operated at ² or less, ultrafiltration membrane,
A microfiltration membrane or the like is used.

In the example of FIG. 13, a plurality of envelope-shaped membranes 3 are formed by independent separation membranes 7, respectively. In the example of FIG. 14, a plurality of envelope-shaped membranes 3 are formed by folding a continuous separation membrane 7.

The outer peripheral surface of the spiral membrane element 1a is covered with a net 8 which is a liquid permeable material. As a material of the net 8, a synthetic resin such as polyolefin, polysulfone, polypropylene, polyester, polyethylene, polystyrene, polyacrylonitrile, or polyamide, or a metal such as stainless steel or iron can be used.

The net 8 preferably has a mesh size of 3 mesh or more and 200 mesh or less. Thereby, the swelling of the spiral membrane element 1a due to the back pressure at the time of backwashing can be reliably suppressed, and the raw water can be sufficiently supplied into the spiral membrane element 1a from the outer peripheral side during operation.

In the spiral separation membrane element 1 shown in FIG. 12, the net 8 is made of tricot cloth impregnated with epoxy resin. The net 8 is 50 mesh, the pitch of the warp and the weft is 0.5 mm, and the diameter of the warp and the weft is 0.15 mm.

The end face of the spiral membrane element 1a may be covered with the net 8 in addition to the outer peripheral face of the spiral membrane element 1a.

As shown in FIG. 15, a resin 81 is applied at equal intervals along the circumferential direction to three places of the net 8 covering the outer peripheral surface of the spiral membrane element 1a, whereby the net 8 is formed. It is fixed to the outer peripheral surface of 1a at three places. The number of locations where the resin 81 is applied is not particularly limited since it depends on the back pressure generated during backwashing. However, if the number of locations where the resin 81 is applied is greater than three, contamination of the outer peripheral portion of the spiral membrane element 1a during backflow cleaning is made. Substances are less likely to be removed. Therefore, for example, in a spiral membrane element 1a having a length of 944 cm, it is preferable to fix about three places with the resin 5a.

The outer peripheral surface of the net 8 is covered with the outer peripheral channel material 5. The material and dimensions of the outer peripheral channel member 5 are the same as those of the outer peripheral channel member 5 shown in FIG.

Note that the entire outer peripheral net 8 may be covered with the outer peripheral channel material 5 or a part of the area may be covered with the outer peripheral channel material 5.

Spiral type membrane element 1 shown in FIG.
The spiral type membrane module provided with the spiral type membrane module is operated by the operation method of the spiral type membrane module shown in FIGS. 4 to 10, for example, like the spiral type membrane module provided with the spiral type membrane element 1 shown in FIG.

In this case, since the outer peripheral surface of the spiral membrane element 1 a is covered with the net 8, contaminants such as turbid substances larger than the pore diameter of the net 8 are contaminated at least at the outer peripheral section of the spiral membrane element 1. Be captured. That is,
Only contaminants smaller than the pore size of the net 8 are enveloped membrane 3
Break in. Therefore, the load on the separation membrane 7 constituting the envelope-shaped membrane 3 is reduced.

FIG. 16 is a partially cutaway perspective view showing the operation of the spiral membrane element shown in FIG. 12 during backwashing.

According to the cleaning method shown in FIG. 16, contaminants adhering to the membrane surface of the spiral type membrane element 1, the raw water spacer 4, the outer peripheral portion and the like, particularly the net 8, can be easily removed, and the outer peripheral portion flow path material can be removed. 5 can be easily discharged to the outside, so that an increase in the resistance of the net 8 can be suppressed. Thereby, a stable amount of permeated water can be maintained.

As described above, in the spiral membrane module provided with the spiral membrane element 1 shown in FIG. 12, the same effect as that described above in the spiral membrane module provided with the spiral membrane element shown in FIG. 1 is obtained. can get.

In the spiral membrane element 1 shown in FIG. 12, since the outer peripheral surface of the spiral membrane element 1a is covered with the net 8, the spiral membrane element 1a
Even if the back pressure generated during backwashing by the contaminants trapped in the outer peripheral portion of the outer peripheral portion increases, the spiral-shaped membrane element 1a is prevented from bulging by the outer peripheral net 8, and the interval between the envelope-shaped membranes 3 does not increase. Therefore, damage to the membrane due to the bulging of the envelope membrane 3 is prevented, and contaminants in the raw water 51 do not leak into the permeated water 52.

In particular, since the net 8 is fixed to the outer peripheral portion of the spiral membrane element 1a at a plurality of locations, the spiral membrane element 1a is reliably prevented from bulging even when the back pressure during backwashing is high. .

Further, the operating method of the spiral membrane element according to the present invention may be applied to the spiral membrane element 1 using a part of the permeated water spacer 6 as a net as shown in FIG. In such a spiral membrane element 1, the permeated water spacer 6 inserted into one envelope-shaped membrane 3 is extended so as to protrude to the outside from the outer peripheral side of the envelope-shaped membrane 3. The extended portion of the spacer 6 forms a net 8 as a spiral membrane element 1a.
Is wound on the outer peripheral surface of. The space between the permeate spacer 6 projecting from the outer peripheral side of the envelope-shaped membrane 3 to the outside and the envelope-shaped membrane 3 is sealed with a resin 6a.

In this case, the swelling of the spiral membrane element 1a due to the back pressure at the time of backwashing can be prevented by the extended permeated water spacer 6, while suppressing the cost of additional parts due to the separate provision of the net 8.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of a spiral membrane element according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an example of an envelope-shaped membrane of the spiral membrane element shown in FIG.

FIG. 3 is a cross-sectional view showing another example of the envelope-shaped membrane of the spiral membrane element shown in FIG.

FIG. 4 is a cross-sectional view showing an example of an operation method of the spiral membrane module according to the present invention.

FIG. 5 is a partially cutaway perspective view showing a cleaning operation in the spiral membrane module of FIG. 4;

FIG. 6 is a sectional view showing still another example of the spiral membrane module according to the present invention.

FIG. 7 is a cross-sectional view showing still another example of the operation method of the spiral membrane module according to the present invention.

FIG. 8 is a partially cutaway perspective view showing a cleaning operation in the spiral membrane module of FIG. 7;

FIG. 9 is a sectional view showing still another example of the operation method of the spiral membrane module according to the present invention.

FIG. 10 is a cross-sectional view showing still another example of the operation method of the spiral membrane module according to the present invention.

FIG. 11 is a front view of a spiral-type membrane element according to another embodiment of the present invention.

FIG. 12 is a partially cutaway perspective view of a spiral membrane element according to still another embodiment of the present invention.

FIG. 13 is a cross-sectional view showing an example of an envelope-shaped membrane of the spiral membrane element shown in FIG.

FIG. 14 is a cross-sectional view showing another example of the envelope-shaped membrane of the spiral membrane element of FIG.

FIG. 15 is a partially cutaway front view of the spiral membrane element of FIG. 12;

FIG. 16 is a partially cutaway perspective view showing a cleaning operation in the spiral membrane module of FIG.

FIG. 17 is a cross-sectional view showing an example in which a permeated water spacer is used as a net.

FIG. 18 is a partially cutaway perspective view of a conventional spiral-type membrane element.

FIG. 19 is an external perspective view of a conventional spiral type membrane element.

FIG. 20 is a cross-sectional view showing an example of an operation method of a conventional spiral type membrane module.

FIG. 21 is a partially cutaway perspective view showing a backwashing operation in a conventional spiral membrane module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 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 8 Net 9 Separation membrane 10 Pressure vessel 13 Raw water inlet 14 Permeated water outlet 51 Raw water 52 Permeated water 61,62 Wire rod 81 Resin

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B01D 65/06 B01D 65/06 (72) Inventor Hajime Hisada 1-1-2 Shimohozumi, Ibaraki-shi, Osaka F-term in Nitto Denko Corporation (reference) 4D006 GA05 GA06 GA07 HA62 HA65 HA95 JA02A JA04A JA04B JA04C JA05A JA05C JA06A JA10A JA10B JA10C JA30A JA30B JA30C JA57A JA58A KA17 KC02 KC03 KC12 KC13 MC24 MC02 MC23 MC23 MC23 MC23

Claims (14)

[Claims] 1. A method for operating a spiral-type membrane module comprising one or a plurality of spiral-type membrane elements housed in a pressure vessel, wherein the spiral-type membrane element is independent of an outer peripheral surface of a perforated hollow tube. Or a spiral membrane element formed by winding a plurality of continuous envelope membranes via a stock solution flow path material, and an outer peripheral portion of the spiral membrane element is covered with a liquid permeable material, The outer peripheral surface side is entirely or partially covered with an outer peripheral channel material, the pressure vessel has one or more liquid ports, and any one of the one or more liquid ports of the pressure vessel is provided. A raw liquid is supplied from at least the outer peripheral side of the spiral membrane element through a hole, and a permeate is taken out from at least one open end of the perforated hollow tube. Rules of operation. 2. A method for operating a spiral-wound membrane module comprising one or a plurality of spiral-wound membrane elements housed in a pressure vessel, wherein the spiral-wound membrane element is independent of an outer peripheral surface of a perforated hollow tube. Or a spiral membrane element formed by winding a plurality of continuous envelope membranes via a stock solution flow path material, and an outer peripheral portion of the spiral membrane element is covered with a liquid permeable material, The outer peripheral surface of the pressure vessel is entirely or partially covered with an outer peripheral channel material, the pressure vessel has a plurality of liquid ports, and the pressure vessel passes through any one of the plurality of liquid ports of the pressure vessel. The undiluted solution is supplied from at least the outer peripheral side of the spiral membrane element, and the permeate is taken out from at least one open end of the perforated hollow tube. A part of the undiluted solution is taken out of the pressure vessel through the liquid inlet / outlet of the spiral type membrane module. 3. The method for operating a spiral type membrane module according to claim 2, wherein at least a part of the stock solution taken out of the pressure vessel is returned to the supply side. 4. A method for cleaning a spiral-wound membrane module comprising one or a plurality of spiral-wound membrane elements housed in a pressure vessel, wherein the spiral-wound membrane element is independent of an outer peripheral surface of a perforated hollow tube. Or a spiral membrane element formed by winding a plurality of continuous envelope membranes via a stock solution flow path material, and an outer peripheral portion of the spiral membrane element is covered with a liquid permeable material, The outer peripheral surface side is entirely or partially covered with an outer peripheral channel material, the pressure vessel has one or a plurality of liquid ports, and a cleaning liquid is introduced from at least one open end of the perforated hollow tube. And
A cleaning liquid discharged from the outer peripheral surface of the perforated hollow tube is discharged from at least an outer peripheral portion of the spiral-type membrane element, and is taken out through one or more liquid ports of the pressure vessel. How to clean the module. 5. The cleaning of the spiral membrane module according to claim 4, wherein the cleaning liquid is a permeate, and at least a part of the permeate taken out of the pressure vessel is returned to a stock solution supply side. Method. 6. A method for cleaning a spiral type membrane module comprising one or more spiral type membrane elements housed in a pressure vessel, wherein the spiral type membrane element is independent of the outer peripheral surface of a perforated hollow tube. Or a spiral membrane element formed by winding a plurality of continuous envelope membranes via a stock solution flow path material, and an outer peripheral portion of the spiral membrane element is covered with a liquid permeable material, The outer peripheral surface side is wholly or partially covered with an outer peripheral channel material, the pressure vessel has a plurality of liquid ports, and introduces a cleaning liquid from at least one open end of the perforated hollow tube, The cleaning liquid derived from the outer peripheral surface of the perforated hollow tube is discharged from at least the outer peripheral portion of the spiral membrane element, and the cleaning liquid is discharged from any one or more of the plurality of liquid ports of the pressure vessel. Taking out to the outside, supplying a stock solution into the pressure vessel through another one of the plurality of liquid ports, and
A method for cleaning a spiral-wound membrane module, comprising taking out to the outside through one liquid port or another liquid port. 7. The cleaning liquid is a permeate, and returns at least a part of the permeate taken out of the pressure vessel and at least a part of the stock taken out of the pressure vessel to the stock supply side. The method for cleaning a spiral-wound membrane module according to claim 6, wherein: 8. A spiral membrane module comprising one or a plurality of spiral membrane elements housed in a pressure vessel, wherein the spiral membrane element is independent or continuous with the outer peripheral surface of a perforated hollow tube. A plurality of envelope-shaped membranes include a spiral-shaped membrane element wound around a stock solution flow path material, an outer peripheral portion of the spiral-shaped membrane element is covered with a liquid-permeable material, and an outer peripheral surface of the liquid-permeable material. The side is wholly or partially covered by an outer peripheral channel material, the pressure vessel has one or more liquid ports, and the pressure vessel is provided through one of the one or more liquid ports of the pressure vessel. A feed system for supplying a stock solution from at least the outer peripheral side of the spiral membrane element; and a take-out system for taking out a permeate from at least one open end of the perforated hollow tube. Spiral membrane module. 9. A spiral-type membrane module comprising one or a plurality of spiral-type membrane elements housed in a pressure vessel, wherein the spiral-type membrane elements are independent or continuous with the outer peripheral surface of a perforated hollow tube. A plurality of envelope-shaped membranes include a spiral-shaped membrane element wound around a stock solution flow path material, an outer peripheral portion of the spiral-shaped membrane element is covered with a liquid-permeable material, and an outer peripheral surface of the liquid-permeable material. The pressure vessel has a plurality of liquid ports, and the spiral type membrane is passed through any one of the plurality of liquid ports of the pressure vessel. A supply system for supplying an undiluted solution from at least the outer peripheral side of the element, a first extraction system for extracting a permeated liquid from at least one open end of the perforated hollow tube; A spiral type membrane module comprising: a second extraction system for extracting a part of the undiluted solution to the outside of the pressure vessel from another of the number of liquid ports. 10. The spiral type membrane module according to claim 9, further comprising a circulation system for returning at least a part of the undiluted solution taken out of the pressure vessel to a supply side again. 11. A spiral-type membrane module comprising one or a plurality of spiral-type membrane elements housed in a pressure vessel, wherein the spiral-type membrane elements are independent or continuous with the outer peripheral surface of a perforated hollow tube. A plurality of envelope-shaped membranes include a spiral-shaped membrane element wound around a stock solution flow path material, an outer peripheral portion of the spiral-shaped membrane element is covered with a liquid-permeable material, and an outer peripheral surface of the liquid-permeable material. The pressure vessel has one or a plurality of liquid inlets and outlets, and an introduction system for introducing a cleaning liquid from at least one open end of the perforated hollow tube. Removing the cleaning liquid derived from the outer peripheral surface of the perforated hollow tube from at least the outer peripheral portion of the spiral membrane element, and extracting the cleaning liquid to the outside from one or more liquid ports of the pressure vessel. A spiral-type membrane module comprising: 12. The cleaning liquid according to claim 11, wherein the cleaning liquid is a permeate, and further comprising a circulation system for returning at least a part of the permeate taken out of the pressure vessel to a stock solution supply side. Spiral membrane module. 13. A spiral-type membrane module comprising one or a plurality of spiral-type membrane elements housed in a pressure vessel, wherein the spiral-type membrane elements are independent or continuous with the outer peripheral surface of a perforated hollow tube. A plurality of envelope-shaped membranes include a spiral-shaped membrane element wound around a stock solution flow path material, an outer peripheral portion of the spiral-shaped membrane element is covered with a liquid-permeable material, and an outer peripheral surface of the liquid-permeable material. The side is entirely or partially covered with an outer peripheral channel material, the pressure vessel has a plurality of liquid ports, and an introduction system for introducing a cleaning liquid from at least one open end of the perforated hollow tube, A cleaning liquid derived from an outer peripheral surface of the perforated hollow tube is discharged from at least an outer peripheral portion of the spiral-type membrane element, and any one or more of the plurality of liquid ports of the pressure vessel may be used. A first take-out system for taking out the stock solution to the outside, a supply system for supplying a stock solution into the pressure vessel through another one of the plurality of solution ports, and a stock solution in the pressure vessel. A spiral-type membrane module, comprising: a second extraction system for extracting the liquid to the outside through a liquid port or another liquid port. 14. The cleaning liquid is a permeate, and circulates at least a part of the permeate taken out of the pressure vessel and at least a part of the stock taken out of the pressure vessel back to the stock supply side. The spiral-type membrane module according to claim 13, further comprising a system.