JP3900624B2 - Membrane separator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a membrane separation device such as a microfiltration device, an ultrafiltration device, and a reverse osmosis membrane separation device, and more particularly to a membrane separation device suitable when a spiral membrane module is used as the membrane module. Specifically, the present invention relates to a membrane separation apparatus in which a plurality of membrane modules are installed in one pressure vessel.
[0002]
[Prior art]
As a membrane module used in a membrane separator, there is a spiral membrane module in which a separation membrane is wound around the outer periphery of a water collecting pipe.
[0003]
FIG. 5 is a partially exploded perspective view showing the structure of a conventional spiral membrane module.
[0004]
A plurality of bag-like separation membranes 2 are wound around the outer periphery of the water collecting pipe 1 via mesh spacers 3.
[0005]
The water collecting pipe 1 is provided with a slit-like opening that communicates the inside and outside of the pipe. The separation membrane 2 has a bag shape, and the central portion surrounds the water collecting pipe 1. A channel material 4 made of mesh spacers or the like is inserted into the bag-shaped separation membrane 2, and the inside of the bag-shaped separation membrane (bag-shaped membrane) 2 is a permeate channel.
[0006]
A top ring 6 and an end ring 7 are provided at both ends of the wound body 5 of the bag-like film 2, and a brine seal 8 is provided around the outer periphery thereof.
[0007]
The raw water flows into the raw water flow path between the bag-like membranes 2 from the front end face of the wound body 5, flows as it is in the longitudinal direction of the wound body 5, and flows out as concentrated water from the rear end face of the wound body 5. . While flowing through this raw water flow path, water permeates the bag-like membrane 2 and enters the inside thereof, flows into the water collecting pipe 1 and is taken out of the module from the rear end side of the water collecting pipe 1.
[0008]
Such a spiral membrane module is housed in a cylindrical pressure vessel, and a raw water inflow chamber is provided on the front end face side of the wound body 5 and a concentrated water outflow chamber is provided on the rear end face side. A permeate discharge pipe is extended in the direction of extension of the axis of the pressure vessel so as to penetrate the center of the concentrated water.
[0009]
A plurality of membrane modules may be accommodated in one cylindrical pressure vessel. In this case, each membrane module is installed in series. That is, the concentrated water flowing out from the rear end surface of the first membrane module flows into the raw water flow path of the second membrane module from the front end surface of the second membrane module, and is concentrated from the rear end surface of the second membrane module. As spills. Similarly, the concentrated water flowing out from the rear end surface of the nth membrane module flows into the raw water flow path of the (n + 1) th membrane module from the front end surface of the (n + 1) th membrane module, and as concentrated water from the rear end surface. leak. The water collecting pipes of each membrane module are connected so as to form one long pipe line penetrating the axial center of the pressure vessel, and the permeated water of each membrane module passes through this one water collecting pipe connecting body. It is taken out.
[0010]
[Problems to be solved by the invention]
In a conventional membrane separation apparatus in which a plurality of membrane modules are installed in one pressure vessel, the raw water flows through each membrane module in series, and the flow resistance of the raw water increases and the treatment efficiency is low.
[0011]
A first object of the present invention is to provide a membrane separation apparatus capable of efficiently performing membrane separation treatment of raw water by installing a plurality of membrane modules in parallel in one pressure vessel.
[0012]
The conventional spiral membrane module has the following problems to be solved.
[0013]
(1) In order to increase the flow rate of the permeated water in the water collecting pipe 1, it is necessary to increase the diameter of the water collecting pipe 1. However, if this is done, the diameter of the spiral membrane module will also increase.
{Circle around (2)} Since the permeated water that has permeated into the bag-like membrane 2 flows to the water collecting pipe 1 while rotating in the bag-like membrane 2 spirally, the flow resistance in the bag-like membrane 2 is large. Moreover, the flow resistance in the vicinity of the collecting pipe slit portion flowing into the collecting pipe 1 from the bag-like membrane 2 is also large.
(3) The flow rate of raw water flowing through the raw water flow path decreases toward the downstream side. (The raw water flow rate is reduced by the amount of the concentrated raw water.) For this reason, the raw water flow velocity is reduced in the downstream area of the raw water flow path, and dirt is likely to adhere.
[0014]
A second object of the present invention is to solve such problems and to provide a membrane separation device including a spiral membrane module that does not require a water collection pipe and has low permeate flow resistance.
[0015]
[Means for Solving the Problems]
The membrane separation apparatus according to the present invention is a membrane separation apparatus in which a membrane module is installed in a pressure vessel, the pressure vessel is cylindrical, and a first chamber is provided in an intermediate portion in the cylinder axis direction. A second chamber is provided on each end in the axial direction, and a third chamber is provided on the cylindrical axis side of the second chamber. The pressure vessel communicates with each chamber outside the pressure vessel. The membrane module is a spiral membrane module in which a permeate flow channel material is disposed inside a bag-shaped membrane, and a raw water flow channel material is disposed between the bag-shaped membranes. The bag-like membrane is substantially square having first, second, third and fourth sides, the first, second and third sides are sealed, and the fourth Part of the side part is an open part and the remaining part is a closed part, and the first side part orthogonal to the fourth side part is applied to the shaft to wind the bag-like film A wound body, the fourth side facing the rear end surface of the wound body, the second side facing the fourth side facing the front end surface of the wound body, In the raw water flow path between the bag-like membranes, the whole of the third side portion is sealed, and in the fourth side portion, a portion overlapping the open portion of the bag-like membrane is a closed portion. And a spiral membrane module in which a portion overlapping the closed portion of the bag-like membrane is an open portion, and the raw water flow path of the membrane module includes a first chamber, a second chamber, and a third chamber. One of the chambers, the permeate channel of the membrane module is in communication with the other of the second chamber and the third chamber , and the opening of the bag-like membrane of the spiral membrane module is the winding Arranged on the outer peripheral side or inner peripheral side of the rear end surface of the rotating body, the raw water flow path is disposed on the inner peripheral side or outer peripheral side of the rear end surface of the wound body, the bag-like membrane Annular member for spacing the concentrated water flowing out from the open portion of the permeate and the raw water flow path flowing from the opening is characterized in that it is connected to the rear end surface of the winding wound body.
[0016]
In such a membrane separation apparatus, since raw water is introduced into a pressure vessel and introduced into each membrane module in parallel and subjected to membrane separation treatment, it is possible to perform efficient membrane separation treatment with low resistance to water flow. it can.
[0017]
In the present invention, the membrane module installed in the pressure vessel is a spiral membrane module in which a permeate flow channel material is disposed inside a bag-shaped membrane and a raw water flow channel material is disposed between the bag-shaped membranes. The bag-like membrane is substantially square having first, second, third and fourth sides, the first, second and third sides are sealed, and the fourth A part of the side part is an open part and the remaining part is a closed part, the first side part orthogonal to the fourth side part is applied to the shaft and the bag-like film is wound to form a wound body, The fourth side portion faces the rear end surface of the wound body, the second side portion facing the fourth side portion faces the front end surface of the wound body, In the raw water flow channel between the whole, the entire third side portion is sealed, and in the fourth side portion, the portion overlapping the open portion of the bag-like membrane is a closed portion, and the bag Filmy Location that overlaps with the chain portion that has become the open section.
[0018]
In such a spiral membrane module, raw water flows into the raw water flow path from the front end face of the wound body. This raw water flows through the raw water flow path in a direction substantially parallel to the winding body axis, and then flows out as concentrated water from the raw water flow path opening portion on the rear end face of the wound body.
[0019]
The water that has passed through the bag-like membrane flows in the bag-like membrane in a direction substantially parallel to the axis of the wound body, and flows out from the opening portion of the bag-like film on the rear end surface of the wound body.
[0020]
Thus, the permeated water flows in the bag-like membrane in a direction parallel to the axis of the wound body, so that the water collecting pipe used in the conventional spiral membrane module is not necessary. And the distribution | circulation resistance at the time of flowing in into this water collection pipe | tube from the bag-like film | membrane is lose | eliminated, and permeated-water distribution resistance becomes small.
[0021]
Since the water collecting pipe is eliminated, the length of the bag-like membrane in the winding direction can be increased by that much, and the membrane area can be expanded. And even if it enlarges the winding direction length of a bag-like film | membrane in this way, the distribution | circulation resistance of permeated water does not increase, and permeated water amount can be increased.
[0022]
In this membrane module, the raw water flow path is opened only at a part of the rear end surface of the wound body, so that the raw water (concentrated water) flow velocity on the downstream side of the raw water flow path can be increased as compared with the conventional one. In addition, it is possible to prevent the adhesion of dirt in the downstream area of the raw water channel.
[0023]
In this membrane module, the open part of the bag-like membrane is disposed on the outer peripheral side or inner peripheral side of the rear end surface of the wound body, and the raw water flow path is disposed on the inner peripheral side or outer peripheral side of the rear end surface of the wound body. cage, the annular member for spacing the concentrated water flowing out from the open portion of the permeate and raw water flow path flowing from the open portion of the bag-shaped membrane that is connected to the rear end face of the winding wound body. The annular member separates the raw water outflow side and the concentrated water outflow side.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0025]
FIG. 6 is a cross-sectional view of the membrane separation apparatus according to the embodiment.
[0026]
A center port (fluid passage) 42 is provided in the middle portion in the longitudinal direction of the cylindrical pressure vessel 40, and a central first chamber (hereinafter referred to as “inflow chamber”) in the pressure vessel 40 from the center port 42. The raw water flows into 44. Two spiral membrane modules 46 and 46 are arranged with the inflow chamber 44 in between. A spacer 48 is disposed between the membrane modules 46 and 46 in order to form the inflow chamber 44 with a predetermined interval between the membrane modules 46 and 46.
[0027]
The membrane module 46 is formed by winding a bag-shaped membrane through a raw water flow path material, and forming a gap between the bag-shaped membranes as a raw water flow path and a bag-shaped membrane inside as a permeate flow path. The raw water in the inflow chamber 44 flows into between the bag-like membranes from one end face of the membrane module 46 and flows through the raw water flow path in a direction substantially parallel to the axial line of the membrane module 46 made of a wound body. Into the second chamber (hereinafter, also referred to as “outflow chamber”) 50 as concentrated water from the outer peripheral side of the other end surface.
[0028]
Side ports 52 are provided on the side peripheral surfaces of both ends of the pressure vessel 40, and the concentrated water in the outflow chamber 50 is taken out of the pressure vessel 40 from the side port 52.
[0029]
An opening for allowing permeate to flow out from the inside of the bag-like membrane is provided in the central portion of the end surface facing the outflow chamber 50 of the wound body of the bag-like membrane, and the permeate passes through this opening to the third chamber. It flows out (in the socket 25). The socket 25 is provided coaxially with a membrane module 46 made of a wound body, and the outside of the socket 25 is an outflow chamber 50.
[0030]
Both ends of the pressure vessel 40 are sealed with end plates 54. An end port 56 is provided at the center of the end plate 54, and the socket 25 communicates with the end port 56.
[0031]
The permeated water that has flowed into the socket 25 from the permeate outflow opening on the end face of the membrane module 46 is taken out of the pressure vessel 40 from the end port 56.
[0032]
The membrane separation apparatus configured as described above includes two membrane modules 46, and each membrane module 46 processes raw water. Two membrane separation apparatuses each provided with one membrane module are arranged side by side. The same amount of permeated water as in the case can be obtained. Moreover, since the two membrane modules 46 are arranged in one pressure vessel 40, the configuration of the membrane separator is compact and the installation area is small. In addition, when the pressure vessel 40 is installed such that the axial direction is the vertical direction, the installation area of the membrane separation device is extremely small.
[0033]
In the above embodiment, the permeated water is taken out from the end port 56, but the permeated water outflow opening of the bag-like membrane is wound around the bag-like membrane as in the spiral membrane module of FIGS. When it is arranged on the outer peripheral side of the membrane module 46 made of a body and communicates with the raw water flow path between the bag-like membranes in the socket 25, the permeated water is taken out from the side port 52, and the concentrated water is the end. Removed from port 56.
[0034]
Next, a spiral membrane module suitable for use in the present invention will be described.
[0035]
FIG. 1A is a perspective view of one bag-like membrane used in this spiral membrane module and a shaft around which the bag-like membrane is wound. 1B and 1C are cross-sectional views taken along lines BB and CC in FIG. 1A, respectively. 2 is a cross-sectional view showing a method of winding a bag-like membrane around a shaft, FIG. 3 is a perspective view showing an engagement relationship between a wound body and a socket, and FIG. 4 is a side view of a spiral membrane module.
[0036]
The bag-like film 10 has a square or rectangular shape, and has a first side part 11, a second side part 12, a third side part 13, and a fourth side part 14. This bag-like membrane 10 is formed by folding a long separation membrane film into two at the second side portion 12 and separating the separation membrane films folded at the first side portion 11 and the third side portion 13 together. It is bonded with an adhesive or the like, and a part of the fourth side portion 14 has a bag shape that is an open portion without bonding.
[0037]
From the middle of the fourth side 14 to the third side 13, the separation membrane films of the bag-like membrane 10 are not adhered to each other, and an open portion 30 for permeate outflow is formed. Moreover, the separation membrane films of the bag-like membrane 10 are bonded to each other from the middle of the fourth side portion 14 to the first side portion 11, thereby forming a closed portion 31 that prevents the permeated water from flowing out. Yes.
[0038]
A channel material (for example, made of a mesh spacer) 15 is inserted and disposed in the bag-like film 10. The bag-like membrane 10 is not limited to one long film folded in two at the second side portion 12 portion, and two separation membrane films are overlapped to form the first side portion 11, A part of the second side part 12, the third side part 13, and the fourth side part 14 may be bonded.
[0039]
An adhesive 16 is attached to one surface of the bag-like film 10 and adhesives 17 and 18 are attached to the other surface, and the bag-like film 10 is wound around the shaft 20. The adhesive 16 is attached along the first side portion 16, and the adhesive 17 is attached along the third side portion 13. The adhesive 18 is attached along the open portion 30 for flowing out the permeated water from the midway portion in the longitudinal direction of the fourth side portion 14 to the third side portion 13.
[0040]
By winding a plurality of bag-like membranes 10 around the shaft 20, the overlapping bag-like membranes 10 are joined in a watertight manner at the portions of the adhesives 16, 17 and 18. Thereby, the raw | natural water flow path through which raw | natural water (and concentrated water) flows is comprised between bag-like membranes 10,10 .... When the adhesive 18 is cured, an open portion for outflow of raw water (concentrated water) is formed on the inner peripheral side and a closed portion for preventing raw water outflow is formed on the outer peripheral side on the rear end surface of the wound body. The
[0041]
A fin 19 extends from the boundary portion between the open portion 30 for permeate outflow and the closed portion 31 for permeate outflow prevention of the fourth side portion 14 toward the rear of the wound body. The fins 19 are made of, for example, a synthetic resin film or sheet, and are preferably bonded to the bag-like film 10 by adhesion or the like.
[0042]
As shown in FIG. 3, the wound body 24 is formed by winding the bag-like membranes 10, 10... Around the shaft 20 through the mesh spacer 29 as shown in FIG. The fins 19 extend from the rear end surface of the wound body 24. By providing the fin 19 at the same location in the fourth side portion 14 of each bag-like film 10, the fin 19 is positioned on the same radius from the axis of the wound body 24, and the fin 19 overlaps. The fin 19 forms a ring-shaped protrusion. The rear end of the cylindrical socket 25 is inserted into the ring-shaped protruding portion, and the socket 25 and the fin 19 are joined with an adhesive or the like. The socket 25 may be externally fitted to the fin 19. Further, a slit groove may be provided on the rear end surface of the wound body 24 along the fin 19 with a lathe, and the end portion of the socket 25 may be embedded in the groove.
[0043]
By joining the socket 25 and the fins 19 in this manner, the permeated water outflow region on the outer peripheral side of the rear end surface of the wound body 24 and the concentrated water outflow region on the inner peripheral side of the socket 25 are partitioned.
[0044]
Note that when the bag-like film 10 is wound around the shaft 20, a mesh spacer 29 is interposed between the bag-like films 10 as shown in FIG. By interposing these mesh spacers 29, a raw water flow path is configured.
[0045]
As shown in FIG. 4, a top ring 26 and an end ring 27 are formed on the front edge and the rear edge of the wound body 24 by a synthetic resin mold, respectively, and a brine seal 28 is provided around the outer periphery of the top ring 26.
[0046]
In the spiral membrane module thus configured, as shown in FIG. 4, raw water flows from the front end surface of the wound body 24 into the raw water flow path between the bag-like membranes 10, 10. This raw water flows through the raw water flow path in a direction substantially parallel to the axial center line of the wound body 24, and is taken out from the inner end face of the socket 25 at the rear end of the wound body 24. And while raw | natural water flows through a raw | natural water flow path in this way, water permeate | transmits in the bag-like film | membrane 10, and permeated water flows out from the outer peripheral side of the socket 25 among the rear-end surfaces of the winding body 24. FIG.
[0047]
In this spiral membrane module, the permeated water flows in the bag-like membrane 10 in the direction parallel to the axial center line of the wound body 24 and is taken out from the rear end surface, so that it is used in the conventional spiral membrane module. No water collection pipe is required. For this reason, there is no flow resistance when flowing from the bag-shaped membrane into the water collecting pipe, and the permeate flow resistance is significantly reduced.
[0048]
Note that the water collecting pipe is omitted, and the length of the bag-like membrane 10 in the winding direction can be increased correspondingly, and the membrane area can be increased. Even if the length of the bag-like membrane in the winding direction is increased, the permeate flow resistance does not increase, and the amount of permeate can be increased.
[0049]
In this embodiment, since the outlet portion of the raw water channel is provided only inside the socket 25 and the outlet (the most downstream portion) of the raw water channel is narrowed down, the downstream side of the raw water channel. Also, the flow rate of the raw water (concentrated water) becomes sufficiently large, and the adhesion of dirt in the downstream area of the raw water channel can be prevented. The inner area and outer area of the socket 25 (the length in the direction of the side portion 14 of the adhesive 18) are preferably determined according to the water recovery rate of the spiral membrane module.
[0050]
Further, in this embodiment, the socket 25 is connected to the wound body 24 using the fins 19, and the connection strength between the socket 25 and the wound body 24 is high. The socket 25 separates the raw water inflow side and the concentrated water outflow side in a watertight manner.
[0051]
In the embodiment of FIGS. 1 to 4, the permeate outflow portion is arranged on the outer peripheral side of the socket 25, and the concentrated water outflow portion is arranged inside the socket 25. The permeated water outflow portion may be used, and the outer peripheral side of the socket 25 may be configured as the concentrated water outflow portion.
[0052]
【The invention's effect】
As described above, the membrane separation device of the present invention is provided with a plurality of membrane modules in one pressure vessel, and can obtain a high permeate flow rate with a compact configuration. The membrane separation apparatus of the present invention has low resistance to water flow and can perform efficient membrane separation treatment.
[Brief description of the drawings]
1A is a perspective view of a bag-like membrane of a spiral membrane module suitable for use in the present invention, FIG. 1B is a cross-sectional view taken along line BB in FIG. c) The figure is sectional drawing which follows CC line of (a) figure.
2 is a cross-sectional view showing a method for winding a bag-like membrane of the spiral membrane module of FIG. 1. FIG.
FIG. 3 is a perspective view showing an engagement relationship between a wound body and a socket.
4 is a side view of the spiral membrane module of FIG. 1. FIG.
FIG. 5 is a partially exploded perspective view showing the structure of a conventional spiral membrane module.
FIG. 6 is a cross-sectional view of the membrane separation apparatus of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Bag-like film | membrane 11 1st edge part 12 2nd edge part 13 3rd edge part 14 4th edge part 15 Channel material 16, 17, 18 Adhesive 19 Fin 20 Shaft 24 Winding body 25 Socket 29 Mesh spacer 30 Opening part 31 for permeate outflow Closing part 40 for preventing permeate outflow Pressure vessel 42 Center port 44 First chamber (inflow chamber)
46 Membrane module 50 Second chamber (outflow chamber)
52 Side port 56 End port

Claims (1)

In a membrane separation device in which a membrane module is installed in a pressure vessel,
The pressure vessel has a cylindrical shape, a first chamber is provided at an intermediate portion in the cylinder axis direction, second chambers are provided at both ends in the cylinder axis direction, and the cylinder of the second chamber is provided. A third chamber is provided on the axial side,
The pressure vessel is provided with a liquid passing part that communicates the interior of the chamber with the outside of the pressure vessel.
The membrane module is a spiral membrane module in which a permeate flow channel material is disposed inside a bag-shaped membrane, and a raw water flow channel material is disposed between the bag-shaped membranes,
The bag-like membrane has a substantially rectangular shape having first, second, third and fourth sides, the first, second and third sides are sealed, and the fourth side is Some are open and the rest are closed.
The first side portion orthogonal to the fourth side portion is applied to the shaft to wind the bag-like film to form a wound body, and the fourth side portion faces the rear end surface of the wound body, The second side facing the fourth side faces the front end face of the wound body,
In the raw water flow path between the bag-like membranes, the whole of the third side portion is sealed, and in the fourth side portion, a portion overlapping the open portion of the bag-like membrane is a closed portion. And a spiral membrane module in which a portion overlapping the closed portion of the bag-like membrane is an open portion,
The raw water flow path of the membrane module communicates with the first chamber and one of the second chamber and the third chamber;
The permeate channel of the membrane module communicates with the other of the second chamber and the third chamber ; and
The open part of the bag-shaped membrane of the spiral membrane module is disposed on the outer peripheral side or inner peripheral side of the rear end surface of the wound body, and the raw water flow path is the inner peripheral side or outer peripheral side of the rear end surface of the wound body. Are located in
An annular member for separating permeated water flowing out from the open part of the bag-like membrane and concentrated water flowing out from the open part of the raw water flow path is connected to the rear end surface of the wound body. Membrane separator.

Images