JPH1057773A - Reverse-osmosis membrane concentrator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the efficiency and reliability of a reverse-osmosis membrane concentrator by rapidly opening or closing the valve for controlling the flow of a liq. to be concentrated and liq. concentrate with a simple mechanism. SOLUTION: A delivery check valve 50 is provided in the passages 52 and 61 connecting the inlet 14 for a liq. to be concentrated of a reverse-osmosis membrane vessel 7 to a front chamber 25. An injection stop valve 58 is furnished in the passages 63 and 82 communicating a liq. concentrate outlet 15 with a rear chamber 26. A suction check valve 42 is provided in the passages 62 and 44 communicating a tank 1 for the liq. to be concentrated with the front chamber. A discharge stop valve 67 is furnished in the passages 82 and 70 for discharging the liq. concentrate from the rear chamber. The needles 48, 56, 40 and 65 of these valves are opened or closed by the pressure change in the front chamber and elastic force. The injection stop valve and the discharge stop valve are opened in an instant by pressure transmitting lines 45 and 53, and the totally closed state is firmly maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reverse osmosis membrane concentrator having an energy recovery function, and more particularly to a reverse osmosis membrane used for desalination of seawater and underground irrigation, wastewater treatment in a chemical process, concentration of fruit juice, and the like. It relates to a concentration device.

[0002]

2. Description of the Related Art A reverse osmosis membrane concentrating apparatus supplies a liquid to be concentrated to a reverse osmosis membrane by applying pressure to the reverse osmosis membrane.
Separate into non-permeate liquid (concentrate) that does not permeate. Some of the various reverse osmosis membrane concentrators have an energy recovery function. In this reverse osmosis membrane concentrator, the liquid to be concentrated is pressurized by a high-pressure pump and supplied to the reverse osmosis membrane, and the concentrated liquid is supplied again to the high-pressure pump without being discharged as a waste liquid. Reuse as power to help power. In order to supply the concentrate to the high-pressure pump again, the flow path is switched by operating a switching valve.

In the above-described conventional reverse osmosis membrane device with an energy recovery function, an external power source such as electric, hydraulic or pneumatic,
Alternatively, the switching valve is operated using a mechanical mechanism to switch the flow path. For this reason, in the conventional reverse osmosis membrane concentrator, the switching mechanism becomes complicated, the production cost increases,
Further, there is a problem that the operation efficiency or the operation reliability is reduced.

[0004] In order to solve such a problem, for example, there is a reverse osmosis membrane concentrating device disclosed in Japanese Patent Application Laid-Open No. Hei 2-21927. This device uses a reciprocating motion of a compression pump to switch a switching valve to recover energy.

[0005]

However, in the case of this device, the switching valve is switched only by a change in the pressure in the front and rear cylinder chambers of the compression pump. High pressure, malfunction of the switching valve, and the like are likely to occur.

Accordingly, the present invention relates to a reverse osmosis membrane concentrator having an energy recovery function, in which a valve for controlling the flow of the liquid to be concentrated and the concentrated liquid is quickly and reliably opened and closed by a simple mechanism, and the reverse osmosis membrane concentration is achieved. An object is to improve the efficiency and reliability of the device.

[0007]

In order to achieve the above-mentioned object, the present invention relates to a reverse osmosis membrane, which is divided into a concentrated liquid side and a permeated liquid side. A reverse osmosis membrane tank provided with a liquid outlet, a double-acting pump for sending the concentrated liquid to the concentrated liquid side of the reverse osmosis membrane tank and introducing the concentrated liquid from the concentrated liquid side; A first passage that connects an inlet to the double-acting pump and guides the liquid to be concentrated from the double-acting pump to the reverse osmosis membrane tank; and a reverse-osmosis membrane tank that connects the concentrate outlet to the double-acting pump. And a second passage for guiding the concentrate to the double-acting pump, the double-acting pump is provided with a cylinder chamber for accommodating a piston, and a front and a front of the piston in the cylinder chamber. At the rear, a front chamber and a rear chamber are formed, respectively. Connects the first passage and a third passage communicating with the supply source of the liquid to be concentrated, and connects the second passage to the rear chamber and a fourth passage for discharging the concentrated liquid in the rear chamber. The first, second, third, and fourth passages each have an opening / closing force due to a pressure change of the front chamber in accordance with an operation of the piston and a valve closing force due to elastic force. First, second, third and fourth valves are provided which are opened and closed by the valve.

That is, each of the second and fourth valves is
A piston portion provided integrally with the valve body, and a cylinder accommodating the piston portion, wherein the cylinder of the second valve communicates with the front chamber via a second valve pressure transmission path; Pressure decrease as a valve-closing force, and pressure increase as a valve-opening force acts on the valve element of the second valve through the piston portion, and connects the cylinder of the fourth valve via a pressure transmission passage for the fourth valve. And the pressure increase in the front chamber acts as a valve closing force and the pressure decrease acts as a valve opening force on the valve body of the fourth valve through the piston portion.

In the reverse osmosis membrane concentrator having the above structure, when the piston is retracted, the pressure in the front chamber decreases and the concentrated liquid in the rear chamber is discharged. The pressure change in the front chamber acts on each of the first, second, third, and fourth valves as a valve opening force or a valve closing force, and causes the third and fourth valves to close.
The valve opens and the first and second valves close. Due to the pressure decrease in the front chamber, the opening of the third valve and the closing of the first valve, the liquid to be concentrated in the supply source is sucked into the front chamber through the third passage. Further, by opening the fourth valve and closing the second valve, the concentrated liquid in the rear chamber is discharged through the fourth passage.

On the other hand, when the piston moves forward, the pressure in the front chamber increases. Due to this pressure change, the first and second
The valve opens and the third and fourth valves close. At this time, since the first, second, third, and fourth valves have a structure in which the elastic force always acts as a valve closing force, switching between opening and closing of each valve is performed only by a pressure change. Is performed more reliably and faster than

Due to the pressure increase in the front chamber, the opening of the first valve and the closing of the third valve, the liquid to be concentrated in the front chamber passes through the first passage,
It is sent to the concentrated liquid side of the reverse osmosis membrane tank through the concentrated liquid inlet. Then, of the liquid to be concentrated that has flowed into the liquid to be concentrated, the liquid that has passed through the reverse osmosis membrane becomes a permeate, and the liquid that has not passed through the reverse osmosis membrane remains on the liquid to be concentrated and becomes liquid concentrated. Further, since the second valve is opened and the fourth valve is closed, the concentrated liquid on the side of the liquid to be concentrated passes through the concentrated liquid outlet and the second passage as the piston advances, and enters the rear chamber. It is pushed in and applies a forward force to the piston in the rear chamber. Thus, the double-acting pump can recover the pressure energy of the concentrate as the driving energy.

In the second and fourth valves, a change in pressure in the front chamber is used as an opening / closing force of the valve body by the pressure transmission path, so that the valve opening operation is performed more quickly and the valve closing state is changed. It is held more firmly.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals indicate the same or corresponding parts. FIG. 1 is a longitudinal sectional view of a reverse osmosis membrane concentrator according to an embodiment of the present invention, FIG. 2 is a view of the reverse osmosis membrane concentrator viewed from the direction of arrow II in FIG. 1, and FIG. FIG. 3 is a sectional view taken along line III-III in FIG. 1. In the following description, the one with the flanged lid member indicated by reference numeral 29 in FIG. 1 is referred to as “front” or “front”, and the one with the crank rod indicated by reference numeral 19 is “rear”.
Alternatively, it is performed as “backward”. The reverse osmosis membrane concentration device includes a reverse osmosis membrane tank 7 and a double-acting pump 8. The inside of the reverse osmosis membrane tank 7 is partitioned by a reverse osmosis membrane 11 into a concentrated liquid side 12 and a permeated liquid side 13. The concentrated liquid side 12 is provided with a concentrated liquid inlet 14 and a concentrated liquid outlet 15, and the permeated liquid side 13 is provided with a permeated liquid outlet 16. The permeated liquid pipe 16 is connected to the permeated liquid outlet 16.

The double-acting pump 8 comprises a crankcase 17 and a cylinder 18. As shown in FIG. 3, the cylinder part 18 and the crankcase part 17 are connected by bolts 75. A crank rod 19 connected to a drive motor 80 is provided in the crank case 17. The crank rod 19 is formed with three crank pin portions 19a.
The axis D of each crank pin portion 19a indicated by a two-dot chain line
Is eccentric from the axis C of the crank rod itself indicated by a dashed line as shown in FIG. Since the crank rod is well known in the technical field of a reciprocating prime mover, a pump, and the like, further detailed description of the crank rod will be omitted. Returning to FIG. 1, a connecting rod 20 is attached to each crank pin portion 19a. The connecting rod 20 is rotatable about a crank pin 19a. A crosshead 22 is rotatably connected to a distal end of each connecting rod 20 via a pin 21. A piston 23 is connected to each crosshead 22.

The cylinder chamber 18 has a cylinder chamber 2 inside.
4 are provided. In each of the cylinder chambers 24,
The piston 23 is housed. In the reverse osmosis membrane concentrating device according to the present embodiment, the three pistons and the peripheral structures associated with each piston are all the same, and the following description of the present embodiment will be directed to one piston.

As shown in FIG. 1, a front chamber 25 and a rear chamber 26 are formed before and after the piston 23 in the cylinder chamber 24. Also, the piston 23 has a sealing member 8 for separating the front chamber 25 and the rear chamber 26 from each other in a liquid-tight manner.
3 are provided. A gland packing 27 and a gland bush 28 are arranged behind the rear chamber 26. The cylinder chamber 24 is sealed by a flanged lid member 29 in front of the piston 23.
In the wall of the cylinder chamber 24, a suction hole 30, a discharge hole 3
1, an injection hole 32 and a discharge hole 33 are provided. A switching block (A) 9 is connected to the suction hole 30 and the injection hole 32 side of the cylinder portion 18. The connection will be described in more detail. In the cylinder portion 18, a concave portion is formed near the suction hole 30 and the injection hole 32, and the convex portion of the switching block (A) 9 is fitted into the concave portion. I have. Similarly, in the cylinder portion 18, a concave portion is formed near the discharge hole 31 and the discharge hole 33, and the convex portion of the switching block (B) 10 is fitted into the concave portion. As shown in FIG. 2, the switching block (A) 9 is connected to the bracket 3 by bolts 35 and 36.
The switching block (B) 10 is fixed to the cylinder unit 18 via a bracket 37 by bolts 38 and 39.

Next, the delivery hole 31, the injection hole 32, the discharge hole 33, and the suction hole 30 provided in the cylinder portion 18 will be described in the above order. As shown in FIGS. 1, 4 and 5, the delivery hole 31 is provided in the switching block (B) 10.
Is connected to a passage 52 formed at the center. Passage 52
The passage 61 is connected to the outlet 61. Further, the delivery port 55 is connected to the concentrated liquid inlet 14 via the concentrated liquid pipe 3. Symbol 50 is
It is a poppet type delivery check valve that opens and closes the passage 52.
The delivery check valve 50 has a valve body 48 that can be engaged with an annular valve seat 49 provided in the middle of the passage 52. Valve body 48
Are arranged in such a direction that the pressure rise in the front chamber 25 acts as a valve opening force. A valve closing force due to the elastic force of the spring 51 always acts on the valve element 48.

The injection hole 32 communicates with a passage 82 formed in the switching block (A) 9. This passage 82
Are connected to a passage 63, and the passage 63 is connected to an inlet 64. Further, the inlet 64 is connected to the concentrate outlet 15 via the concentrate pipe 4. As described above, the reverse osmosis membrane concentrating device of the present embodiment includes the piston 23,
Although it has three cylinder chambers 24 and three peripheral structures associated therewith, three concentrate pipes 4 for guiding the concentrate into the rear chamber 26 are provided independently for each cylinder. Reference numeral 58 denotes a poppet-type injection stop valve that opens and closes the passage 82. The injection stop valve 58 is connected to the annular valve seat 5 near the injection hole 32.
The valve body 56 includes a valve body 56 engageable with the valve body 7, a piston portion 59 provided integrally with the valve body 56, and an injection stop valve cylinder 46 for accommodating the piston portion 59 in a reciprocating manner. Valve body 56
Are arranged in such a direction that the pressure rise in the rear chamber 26 acts as a valve opening force. As described above, since the valve body 56 and the piston portion 59 are integrally connected, when the piston portion 59 moves in one direction, the valve body 56 also moves in the same direction. Reference numeral 46 a denotes a space formed on the valve body 65 side of the piston portion 59 in the injection stop valve cylinder 46 when the valve body 56 is engaged with the valve seat 57. A spring 60 is provided on the opposite side of the piston portion 59 from the valve body 56. The spring 60 applies an elastic force to the piston portion 59 toward the valve body 56. For this reason,
The valve closing force due to the elastic force of the spring 60 is transmitted to the valve body 56 via the piston portion 59 and is constantly acting.

The discharge hole 33 is provided in the switching block (B) 10
Is formed in communication with a passage 81 formed at the center. This passage 81
Are connected to a passage 70, and the passage 70 is connected to an outlet 71. The drainage pipe 5 is connected to the discharge port 71. Reference numeral 67 denotes a poppet-type discharge stop valve 67 that opens and closes the passage 81. The discharge stop valve 67 houses a valve body 65 engageable with an annular valve seat 66 near the discharge hole 33, a piston portion 68 provided integrally with the valve body 65, and the piston portion 68 reciprocally movable. Discharge stop valve cylinder 5
And 4. The valve body 65 is arranged in such a direction that the pressure rise in the rear chamber 26 acts as a valve opening force. As described above, since the valve body 65 and the piston portion 68 are integrally connected, when the piston portion 68 moves in one direction, the valve body 65 also moves in the same direction. Reference numeral 54a is
When the valve body 65 is engaged with the valve seat 66, the space is formed on the side of the piston portion 68 opposite to the valve body 65 in the discharge stop valve cylinder 54. A valve closing force due to the elastic force of the spring 69 provided in the passage 81 always acts on the valve body 65.

The suction hole 30 is provided in the switching block (A) 9
Is formed in communication with a passage 44 formed at the center. This passage 44
Is connected to the passage 62, and the passage 62 is connected to the suction port 47. Furthermore, the suction port 47 is connected to the concentrated liquid supply pipe 2.
Is connected to the liquid tank 1 to be concentrated. Code 42
Is a poppet type suction check valve 42 that opens and closes a passage 44.
It is. The suction check valve 42 has a valve body 40 that can be engaged with an annular valve seat 41 provided in the middle of the passage 44. The valve element 40 is disposed in such a direction that the pressure decrease in the front chamber 25 acts as a valve opening force. The valve body 40 has a spring 4
The valve closing force due to the elastic force of No. 3 always acts.

Reference numeral 53 denotes a pressure transmission path that communicates the passage 52 with the discharge stop valve cylinder 54 of the discharge stop valve 67. More specifically, one end of the pressure transmission passage 53 is connected to a portion between the delivery hole 31 and the valve seat 49 in the passage 52, and the other end forms a space 54 a in the discharge stop valve cylinder 54. Connected to the part to be. Reference numeral 45 denotes a pressure transmission path that communicates the passage 44 with the injection stop valve cylinder 46 of the injection stop valve 58. More specifically, the pressure transmission path 45
Is connected to a portion of the passage 44 between the suction hole 30 and the valve seat 41, and the other end is connected to a portion of the injection stop valve cylinder 46 where a space 46 a is formed.

Next, the operation of the reverse osmosis membrane concentrator will be described mainly with reference to FIGS. 1, 4 and 5. In the double-acting pump 8 of the reverse osmosis membrane concentrator, the crank rod 19 is rotated by the drive motor 80. As a result, the crosshead 22 and the piston 23 connected to the crank rod 19 via the connecting rod 20
It reciprocates back and forth by the eccentric action of a. The operation of the double-acting pump 8 is divided into a suction stroke of the liquid to be concentrated and a discharge stroke of the liquid to be concentrated by the reciprocating motion of the piston 23 described above.

First, the suction stroke of the liquid to be concentrated in the double-acting pump 8 will be described. The state shown in FIG. 4 is a state in which the piston 23 is most advanced with respect to the reciprocating motion, and this state is a start state of the suction stroke. In the rear chamber 26, it is assumed that the concentrated liquid pushed when the piston 23 has advanced in the immediately preceding delivery stroke is stored. From this state, when the piston 23 starts to retreat in the direction B, the pressure in the front chamber 25 decreases, and the concentrated liquid in the rear chamber 26 is discharged.

Each valve provided in the reverse osmosis membrane concentrator is in the following state. First, in the suction check valve 42, a valve opening force due to a decrease in pressure in the front chamber 25 and a valve closing force of the spring 43 act on the valve body 40. However, since the valve opening force is greater than the valve closing force, the suction check valve 42 opens.

In the delivery check valve 50, the valve body 48 has a valve closing force due to a decrease in pressure in the passage 52 and a spring 5.
A valve closing force of 1 acts. Therefore, the delivery check valve 5
0 closes the valve.

In the injection stop valve 58, first, the valve closing force of the spring 60 acts on the valve body 56 via the piston portion 59. Further, when the pressure in the front chamber 25 decreases, the pressure in the space 46 a in the injection stop valve cylinder 46 communicated by the passage 44 and the pressure transmission path 45 also decreases. , A force directed toward the injection hole 32 acts. This injection hole 32
Is a valve closing force for the valve body 56. on the other hand,
Since the pressure in the rear chamber 26 slightly increases due to the retreat of the piston 23, the valve opening force due to the slight increase in pressure acts on the valve body 56. However, since the sum of the valve closing forces is greater than the valve opening force, the injection stop valve 58 is closed. Further, in this embodiment, in addition to the valve closing force of the spring 60, the valve closing force of the pressure transmission path 45 acts on the valve body 56, so that the pressure in the rear chamber 26 slightly increases when the piston 23 retreats. However, the valve body 56 does not open, and the fully closed state of the valve body 56 is maintained more firmly.

In the discharge stop valve 67, a valve closing force is applied to the valve body 65 by a spring 69. However, since the pressure in the rear chamber 26 slightly increases due to the retreat of the piston 23, the valve opening force due to the slight increase in pressure acts on the valve body 65. Further, when the pressure in the front chamber 25 decreases, the pressure in the space 54a in the discharge valve cylinder 54 communicated by the passage 52 and the pressure transmission path 53 also decreases, so that the piston portion 68 in the discharge valve cylinder 54
, A force acts in a direction away from the discharge hole 33. The force in the direction away from the discharge hole 33 becomes a valve opening force for the valve body 65. Since the sum of the valve opening forces acting on the valve body 65 is greater than the valve closing force of the spring 69 acting on the valve body 65, the discharge stop valve 67 opens.

Thus, in the suction stroke of the liquid to be concentrated,
The piston 23 retracts, the pressure in the front chamber 25 decreases, and the suction check valve 42 opens and sends out, and the check valve 50 closes. The concentrated liquid is sucked into the front chamber 25 through the concentrated liquid supply pipe 2, the suction port 47, the passage 62, the passage 44, and the discharge hole 31. Further, since the injection stop valve 58 closes and the discharge stop valve 67 opens, the double-acting pump 8 discharges the concentrated liquid stored in the rear chamber 26 through the discharge hole 33, the passage 81, the passage 70, Exit 7
1 and discharged to the outside via the exhaust liquid pipe 5 (see FIGS. 1 and 4). The suction stroke ends when the piston 23 at the position shown in FIG. 4 is retracted in the direction B and reaches the position shown in FIG.

Next, the process of delivering the liquid to be concentrated will be described. The state shown in FIG. 5 is a state in which the piston 23 is most retracted, and is a state in which the above-described suction stroke has been completed. The sending process starts from the state shown in FIG. In addition, front room 2
5 stores the liquid to be concentrated sucked during the suction stroke. When the piston 23 starts to advance in the direction A from the position shown in FIG. 5, the pressure in the front chamber 25 increases and the pressure in the rear chamber 26 slightly decreases.

As the piston 23 advances, the valves provided in the reverse osmosis membrane concentrator are in the following states. First, in the suction check valve 42, a valve closing force due to a pressure increase in the front chamber 25 and a valve closing force of the spring 43 act on the valve body 40. Therefore, the suction check valve 42 is closed.

In the delivery check valve 50, the valve body 48 has a valve opening force due to a rise in pressure in the passage 52 and a spring 5.
A valve closing force of 1 acts. However, since the valve opening force is greater than the valve closing force, the delivery check valve 50 opens.

In the injection stop valve 58, first, the valve closing force of the spring 60 acts on the valve body 56 via the piston portion 59. Further, a valve closing force is applied to the valve body 56 by the minute pressure of the rear chamber 26. On the other hand, when the pressure in the front chamber 25 increases, the passage 44 and the pressure transmission path 4
5 a space 46 in the injection stop valve cylinder 46
Since the pressure of “a” also increases, a force in a direction away from the injection hole 32 acts on the piston portion 59 in the injection stop valve cylinder 46. The force in the direction away from the injection hole 32 is
The valve opening force acts on the valve body 56. Since the valve opening force acting on the valve body 56 is larger than the valve closing force acting on the valve body 56, the injection stop valve 58 is opened. The above-described valve opening operation of the valve body 56 is performed by transmitting the pressure increase of the front chamber 25 to the piston portion 59 and the valve body 56 via the pressure transmission path 45, so that the instantaneous Done in

In the discharge stop valve 67, first, a valve closing force of a spring 69 acts on the valve body 65. Further, a valve closing force is applied to the valve body 65 by the minute pressure of the rear chamber 26. Further, when the pressure in the front chamber 25 increases, the passage 52
And the pressure in the discharge stop valve cylinder 54 communicated by the pressure transmission path 53 also increases, so that the discharge stop valve cylinder 5
A force directed to the discharge hole 33 acts on the piston portion 68 in 4. The force directed to the discharge hole 33 becomes a valve closing force for the valve body 65. Therefore, the discharge stop valve 67 closes.

As described above, in the delivery process of the liquid to be concentrated,
The piston 23 moves forward to compress the liquid to be concentrated in the front chamber 25, and the suction check valve 42 closes and sends out the check valve 5.
Since the valve 0 is opened, the double-acting pump 8 causes the liquid to be concentrated in the front chamber 25 to pass through the reverse osmosis membrane via the discharge hole 31, the passage 52, the passage 61, the discharge port 55, and the concentrated liquid pipe 3. It is sent out into the tank 7 (see also FIG. 1). Then, of the liquid to be concentrated that has flowed into the reverse osmosis membrane tank 7,
The permeated liquid is taken out from the permeated liquid side 13 through the permeated liquid outlet 16 and the permeated liquid pipe 6 to the outside. On the other hand, those which have not passed through the reverse osmosis membrane 11 remain on the concentrated liquid side 12 and become concentrated liquid.

Further, the injection stop valve 5 is provided by the pressure transmission path 45.
Since the valve 8 instantaneously opens and the discharge stop valve 67 closes, the concentrated liquid in the concentrated liquid side 12 is discharged by the advance of the piston 23, the concentrated liquid outlet 15, the concentrated liquid pipe 4, the injection port 64, the passage 6
3. It is pushed into the rear chamber 26 through the passage 82 and the injection hole 32. At this time, since the discharge stop valve 67 is closed, the concentrated liquid is introduced into the rear chamber 26 while maintaining the pressure, and applies the pressure in the direction A (see FIG. 5), that is, the forward force to the piston 23. I do. When the concentrated liquid is introduced into the rear chamber 26, the valve 65 opens slightly due to the pressure of the concentrated liquid, the concentrated liquid leaks, and a desired forward force is applied to the piston 23.
However, in this embodiment, the pressure transmission path 53 is provided as described above, the pressure of the front chamber 25 is transmitted to the valve body 65 as a valve closing force, and the discharge stop valve 67 is fully closed. Is more firmly maintained, so that the valve body 65 is reliably prevented from opening. Therefore, the double-acting pump 8
The concentrated liquid can be separated into the permeated liquid and the concentrated liquid, and the pressure energy of the concentrated liquid introduced into the rear chamber 26 can be recovered as driving energy when the piston advances.
Further, the magnitude of the energy recovered as the driving energy depends on [the area Ac of the cylinder chamber 24-the area Ar of the shaft portion of the piston 23]. The concentrated liquid guided into the rear chamber 26 is discharged to the outside through the discharge pipe 5 in a subsequent suction stroke of the liquid to be concentrated.

According to this embodiment configured as described above, the following excellent effects can be obtained. (A) Delivery check valve 50, injection stop valve 58, discharge stop valve 6
7 and the suction check valve 42 are opened and closed by the change in pressure in the front chamber 25 and the elastic force of the spring. Is performed more reliably and quickly than For this reason, there is no possibility that the liquid to be concentrated is trapped in the front chamber 25 or the concentrated liquid is trapped in the liquid concentrate side 12 or the rear chamber 26 because the opening / closing timing does not match. Therefore, occurrence of abnormal compression is prevented.

(B) Delivery check valve 50, injection stop valve 5
8. Since the electric motor and other driving sources are not used for switching the opening and closing of the discharge stop valve 67 and the suction check valve 42, there is no valve opening / closing failure due to the failure of the driving source. in addition,
The reverse osmosis membrane concentrator can be reduced in size and cost.

(C) Delivery check valve 50, injection stop valve 5
8. Since the opening and closing of the discharge stop valve 67 and the suction check valve 42 are poppet-type valves, they can be performed more reliably and quickly as compared with other types of valves. Therefore, when fully closed, the liquid to be concentrated or the concentrated liquid does not leak from between the valve seat and the valve element, and the energy recovery efficiency is improved.

(D) Injection stop valve 58 and discharge stop valve 67
Since the valve is instantaneously opened or firmly closed by the pressure transmission paths 45 and 53, the concentrated liquid in the rear chamber 26 is reliably discharged during the suction stroke of the concentrated liquid, and In the concentrated liquid delivery process, the concentrated liquid introduced into the rear chamber 26 effectively applies a forward force to the piston 23 without reducing the pressure, and the driving force of the piston 23 can be reduced. .

[0040]

Since the present invention is configured as described above, it has the following effects. According to the first aspect of the present invention, the opening and closing of each valve is performed by the pressure change due to the operation of the piston and the elastic force of the spring, so that it is more reliable than the conventional case where the valve is opened and closed only by the pressure change. And done quickly. According to the invention as set forth in claim 2, since the pressure change in the front chamber is used as the opening / closing force of the valve via the pressure transmission path, the valve opening operation is performed instantaneously,
In addition, the valve closing state is more firmly maintained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a reverse osmosis membrane concentration device according to an embodiment of the present invention.

FIG. 2 shows a reverse osmosis membrane concentrating device as indicated by an arrow II in FIG.
It is the figure seen from the direction.

FIG. 3 is a cross-sectional view of the reverse osmosis membrane concentrator taken along the line III-III in FIG.

FIG. 4 is a diagram showing a state in which a piston is most advanced in a reverse osmosis membrane concentrating device according to the present embodiment.

FIG. 5 is a diagram showing a state in which a piston is most retracted in the reverse osmosis membrane concentration device according to the present embodiment.

[Explanation of symbols]

1 ... concentrated liquid tank (supply source), 2 ... concentrated liquid supply pipe (third passage), 3 ... concentrated liquid pipe (first passage), 4 ... concentrated liquid pipe (second passage), 5 ... discharge Liquid pipe (fourth passage), 7: reverse osmosis membrane tank, 8: double-acting pump, 11: reverse osmosis membrane, 12: concentrated liquid side, 13: permeated liquid side, 14: concentrated liquid inlet, 15
... Concentrate outlet, 23 ... Piston, 24 ... Cylinder chamber, 2
5 front chamber, 26 rear chamber, 42 suction check valve (third chamber)
Valve), 45 ... pressure transmission path (second valve pressure transmission path), 46
... Injection stop valve cylinder (cylinder), 50 ... Delivery check valve (first valve), 53 ... Pressure transmission path (4th valve pressure transmission path), 54 ... Discharge stop valve cylinder (cylinder), 56 ... Valve Body, 58: injection stop valve (second valve), 59: piston part,
65: valve element, 67: discharge stop valve (fourth valve), 68: piston part.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Makoto Okumura 1-14 Nakamachi, Moji-ku, Kitakyushu-shi, Fukuoka Prefecture Okano Valve Manufacturing Co., Ltd.

Claims (2)

[Claims] A reverse osmosis membrane (11) on the side of a liquid to be concentrated (12)
And the permeated liquid side (13), and the concentrated liquid side (1
2) Concentrated liquid inlet (14) and concentrated liquid outlet (15)
Reverse osmosis membrane tank (7) provided with
A double-acting pump (8) for sending the concentrated liquid to the concentrated liquid side (12) and introducing the concentrated liquid from the concentrated liquid side (12); the concentrated liquid inlet (14); A first passage (3) connected to a pump (8) for guiding the liquid to be concentrated from the double-acting pump (8) to the reverse osmosis membrane tank (7); A second passage (4) connected to a pump (8) for introducing the concentrated solution from the reverse osmosis membrane tank (7) to the double-acting pump (8). The pump (8) has a piston (2
3) a cylinder chamber (24) for accommodating therein a front chamber (25) and a rear chamber (26) in front of and behind the piston (23) in the cylinder chamber (24), respectively.
And the first chamber (25) is formed in the front chamber (25).
And a third passage (2) communicating with the supply source (1) of the liquid to be concentrated, and the rear chamber (26) is connected to the second passage.
A passage (4) is connected to a fourth passage (5) for discharging the concentrated liquid in the rear chamber (26), and the first, second,
Each of the third and fourth passages (3, 4, 2, 5) has an opening / closing force due to a pressure change of the front chamber (25) according to an operation of the piston (23) and a valve closing force due to elastic force. First, second, third and fourth valves (50, 58, 4)
2, 67), wherein the reverse osmosis membrane concentrator is provided. 2. Each of the second and fourth valves (58, 67) includes a piston portion (59, 68) integrally provided on a valve body (56, 65), and a piston portion (59, 68). ) For accommodating the cylinder (46) of the second valve (58) and the pressure transmission path (4) for the second valve.
5) through the piston portion (59) through the piston portion (59) as a valve closing force and a pressure decrease in the front chamber (25) as a valve closing force.
6), and the cylinder (54) of the fourth valve (67) communicates with the front chamber (25) via a fourth valve pressure transmission path (53). 2. The reverse osmosis membrane concentrator according to claim 1, wherein the pressure increase acts as a valve closing force and the pressure decrease acts as a valve opening force on the valve body (65) through the piston portion (68). apparatus.