A reverse osmosis system energy recovery device

Abstract

The present invention provides a reverse osmosis system energy recovery device, characterized in that it includes piston 1, piston 1 cylinder body, piston 2, piston 2 cylinder body, inlet of medium to be pressurized, outlet of medium to be pressurized, one-way valve 1, one-way valve 2, one-way valve 3, one-way valve 4, inlet of medium to be recovered, outlet of medium to be recovered, control valve 1, control valve 2, control valve 3, control valve 4, piston 1 limit plate, piston 1 limit plate spring, piston 2 limit plate, piston 2 limit plate spring, piston rod, working chamber 1, recovery chamber 1, working chamber 2 and recovery chamber 2, wherein when the control valve 3 is opened with the control valve 2, the control valve 1 is closed with the control valve 4, and when the control valve 1 is opened with the control valve 4, the control valve 3 is closed with the control valve 2. According to the energy recovery device of a reverse osmosis system of the present invention, the operation is stable, the piston has no collision, and under certain conditions, a booster pump is not required, and the flow rate is convenient to adjust.

Description

Technical Field

[0001] The present invention relates to the technical field of energy recovery devices, and in particular to an energy recovery device for a reverse osmosis system. Background Art

[0002] In the reverse osmosis desalination process, the valve-controlled energy recovery devices on the market are currently represented by DWEER and SalTec products. DWEER uses LinX valves and SalTec uses rotary valves to switch the high and low pressure paths of concentrated water, which have the following disadvantages:

[0003] Due to the compressibility of water, when the valve is switched, the impact is large and the operation is not stable;

[0004] It is composed of two or three hydraulic cylinders arranged in parallel and has a large volume;

[0005] The piston slides freely in the hydraulic cylinder, which may cause the risk of collision at both ends. An additional piston position detection device is needed to avoid the risk of collision.

[0006] A booster pump is required;

[0007] For brief information about DWEER and SalTec, please refer to the paper "Variable Load Operation and Stability Evaluation of Reciprocating Switching Valve-Controlled Energy Recovery Device".

[0008] The energy recovery device described in patents CN102588240B and CN110563089A uses a pilot valve to control a reversing valve, which switches the high and low pressure passages of concentrated water. The switching speed is relatively fast. Considering the compressibility of water, there is a risk of large impact and unstable operation when the reversing valve is switched.

[0009] In the reverse osmosis desalination process, the existing energy recovery device has a relatively complicated process for adjusting the recovery flow rate, and the flow rate adjustment is inconvenient. Summary of the invention

[0010] The technical problem to be solved by the present invention is to provide an energy recovery device for a reverse osmosis system, in which the control valve does not produce obvious impact when working, runs smoothly and has a long service life; the piston has a self-limiting function to prevent collision; when the inlet pressure of the pressurized medium is sufficient, a booster pump is not required; when specific conditions are met, the flow rate of the recovered medium can be conveniently adjusted.

[0011] In order to solve the above technical problems, the present invention provides an energy recovery device for a reverse osmosis system, characterized in that it comprises a piston 1, a piston 1 cylinder body, a piston 2, a piston 2 cylinder body, an inlet for a medium to be pressurized, an outlet for a medium to be pressurized, a one-way valve 1, a one-way valve 2, a one-way valve 3, a one-way valve 4, an inlet for a medium to be recovered, an outlet for a medium to be recovered, a control valve 1, a control valve 2, a control valve 3, a control valve 4, a piston 1 limit plate, a piston 1 limit plate spring, a piston 2 limit plate, a piston 2 limit plate spring, a piston rod, a working chamber 1, a recovery chamber 1, a working chamber 2 and a recovery chamber 2, wherein the piston 1 and the piston 2 are fixed on the piston rod, the piston 1 cylinder body is divided into two chambers, the working chamber 1 and the recovery chamber 1, by the piston 1, and the medium to be pressurized The medium inlet is in one-way communication with the working chamber one through the one-way valve one, the working chamber one is in one-way communication with the outlet of the medium to be pressurized through the one-way valve two, the recovery chamber one is in communication with the inlet of the medium to be recovered through the control valve one, the recovery chamber one is in communication with the outlet of the medium to be recovered through the control valve two, the piston cylinder body is divided into two chambers, the working chamber two and the recovery chamber two, by the piston two, the medium inlet is in one-way communication with the working chamber two through the one-way valve three, the working chamber two is in one-way communication with the outlet of the medium to be pressurized through the one-way valve four, the recovery chamber two is in communication with the inlet of the medium to be recovered through the control valve three, and the recovery chamber two is in communication with the outlet of the medium to be recovered through the control valve four The piston 1 limit plate is arranged in the working chamber 1, and the piston 1 limit plate spring is arranged between the piston 1 limit plate and the piston 1. The piston 2 limit plate is arranged in the working chamber 2, and the piston 2 limit plate spring is arranged between the piston 2 limit plate and the piston 2. When the control valve 3 and the control valve 2 are opened, the control valve 1 and the control valve 4 are closed. The recovery chamber 2 is connected with the inlet of the medium to be recovered, and the recovery chamber 1 is connected with the outlet of the medium to be recovered. The piston 2 moves toward the direction of the working chamber 2 under the pressure of the medium to be recovered, and the volume of the working chamber 2 is compressed. The medium to be pressurized in the working chamber 2 is discharged into the outlet of the medium to be pressurized through the one-way valve 4. , the piston 1 and the piston 2 move synchronously, the volume of the working chamber 1 increases with the movement of the piston 1, the pressurized medium enters the working chamber 1 through the one-way valve 1, and when the piston 2 limit plate reaches the specified position, the piston 2 limit plate seals the passage from the working chamber 2 to the one-way valve 4, the volume of the working chamber 2 cannot be further compressed, the piston 2 stops moving, when the control valve 1 and the control valve 4 are opened, the control valve 3 and the control valve 2 are closed, the recovery chamber 1 is connected with the inlet of the medium to be recovered, and the recovery chamber 2 is connected with the outlet of the medium to be recovered, the piston 1 moves toward the working chamber 1 under the pressure of the medium to be recovered, and the volume of the working chamber 1 is compressed,The medium to be pressurized in the working chamber 1 passes through the one-way valve 2 and is discharged into the outlet of the medium to be pressurized. The piston 2 moves synchronously with the piston 1. The volume of the working chamber 2 increases with the movement of the piston 2. The medium to be pressurized enters the working chamber 2 through the one-way valve 3. When the piston 1 limit plate reaches the specified position, the piston 1 limit plate seals the passage from the working chamber 1 to the one-way valve 2. The volume of the working chamber 1 cannot be further compressed. The piston 1 stops moving. When the piston 1 moves toward the working chamber 1, the piston 2 limit plate is reset under the action of the piston 2 limit plate spring. When the piston 2 moves toward the working chamber 2, the piston 1 limit plate is reset under the action of the piston 1 limit plate spring. The opening speed, closing speed, opening sequence, closing sequence and opening and closing frequency of the control valve 1, the control valve 2, the control valve 3 and the control valve 4 are controllable.

[0012] Optionally, the control valve one, the control valve two, the control valve three and the control valve four are opened and closed by a cam tappet mechanism.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] The reverse osmosis system energy recovery device of the present invention has a control valve that does not generate obvious impact when working, operates smoothly, and has a long service life; the piston has a limit function to prevent collision.

[0015] When the inlet pressure of the pressurized medium is sufficient, a booster pump is not required.

[0016] When specific conditions are met, the flow rate of the recovered medium can be easily adjusted.

[0017] The reverse osmosis system energy recovery device of the present invention drives the opening and closing of the control valve through a cam tappet mechanism, and has a simple and reliable structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0019] Figure 1 A top view of an energy recovery device for a reverse osmosis system according to an embodiment of the present invention;

[0020] Figure 2 for Figure 1 A schematic cross-sectional structure diagram of a reverse osmosis system energy recovery device along line AA;

[0021] Figure 3 for Figure 2 A schematic cross-sectional structure diagram of a reverse osmosis system energy recovery device along line BB; DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with specific embodiments and drawings. More details are elaborated in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from the description herein. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the protection scope of the present invention should not be limited by the content of this specific embodiment.

[0023] Figure 1 This is a top view of a reverse osmosis system energy recovery device according to an embodiment of the present invention. Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure of a reverse osmosis system energy recovery device along line AA, Figure 3 for Figure 2 A schematic diagram of the cross-sectional structure of a reverse osmosis system energy recovery device along line BB is shown in FIG. Figure 1 , Figure 2 , Figure 3As shown, the energy recovery device of the reverse osmosis system may include a piston 1, a piston cylinder 2, a piston 3, a piston cylinder 4, an inlet 5 for a medium to be pressurized, an outlet 6 for a medium to be pressurized, a one-way valve 7, a one-way valve 2, a one-way valve 3, a one-way valve 4, an inlet 11 for a medium to be recovered, an outlet 12 for a medium to be recovered, a control valve 13, a control valve 2 14, a control valve 3 15, a control valve 4 16, a piston one limit plate 17, a piston one limit plate spring 18, a piston two limit plate 19, a piston two limit plate spring 20, a piston rod 21, a working chamber 1 22, a recovery chamber 1 23, a working chamber 2 24 and a recovery chamber 2 25, wherein the piston 1 and the piston 2 3 are fixed on the piston rod 21, and the piston cylinder 2 is divided into a working chamber and a recovery chamber by the piston 1. The inlet 5 of the medium to be pressurized is connected to the working chamber 22 in one-way through the one-way valve 7, the working chamber 22 is connected to the outlet 6 of the medium to be pressurized in one-way through the one-way valve 8, the recovery chamber 23 is connected to the inlet 11 of the medium to be recovered through the control valve 13, and the recovery chamber 23 is connected to the outlet 12 of the medium to be recovered through the control valve 2 14. The piston cylinder 4 is divided into two cavities, the working chamber 24 and the recovery chamber 25, by the piston 2 3. The inlet 5 of the medium to be pressurized is connected to the working chamber 24 in one-way through the one-way valve 3 9, the working chamber 24 is connected to the outlet 6 of the medium to be pressurized in one-way through the one-way valve 4 10, the recovery chamber 25 is connected to the inlet 11 of the medium to be recovered through the control valve 3 15, and the recovery chamber 25 is connected to the inlet 11 of the medium to be recovered through the control valve 4 1 6 is connected with the outlet 12 of the medium to be recovered, a piston limit plate 17 is arranged in the working chamber 1 22, a piston limit plate spring 18 is arranged between the piston limit plate 17 and the piston 1, a piston limit plate 19 is arranged in the working chamber 2 24, and a piston limit plate spring 20 is arranged between the piston limit plate 19 and the piston 2 3. When the control valve 3 15 and the control valve 2 14 are opened, the control valve 1 13 and the control valve 4 16 are closed, the recovery chamber 2 25 is connected with the inlet 11 of the medium to be recovered, and the recovery chamber 1 23 is connected with the outlet 12 of the medium to be recovered. Under the pressure of the medium to be recovered, the piston 2 3 moves toward the direction of the working chamber 2 24, the volume of the working chamber 2 24 is compressed, and the medium to be pressurized in the working chamber 2 24 passes through the one-way valve 4 10 and is discharged into the medium to be pressurized. The pressure medium outlet 6, piston 1 and piston 2 3 make synchronous movement, the volume of working chamber 1 22 increases with the movement of piston 1, and the pressurized medium enters the working chamber 1 22 through the one-way valve 1 7. When the piston 2 limit plate 19 reaches the specified position, the piston 2 limit plate 19 seals the passage from the working chamber 2 24 to the one-way valve 4 10, and the volume of the working chamber 2 24 cannot be further compressed. The piston 2 3 stops moving. When the control valve 1 13 and the control valve 4 16 are opened, the control valve 3 15 and the control valve 2 14 are closed, the recovery chamber 1 23 is connected with the inlet 11 of the medium to be recovered, and the recovery chamber 2 25 is connected with the outlet 12 of the medium to be recovered. The piston 1 moves toward the direction of the working chamber 1 22 under the pressure of the medium to be recovered, and the volume of the working chamber 22 is compressed.The medium to be pressurized in the working chamber 1 22 passes through the one-way valve 2 8 and is discharged into the outlet 6 for the medium to be pressurized. The piston 2 3 moves synchronously with the piston 1. The volume of the working chamber 2 24 increases with the movement of the piston 2 3. The medium to be pressurized enters the working chamber 2 24 through the one-way valve 3 9. When the piston 1 limit plate 17 reaches the specified position, the piston 1 limit plate 17 seals the passage from the working chamber 1 22 to the one-way valve 2 8. The volume of the working chamber 1 22 cannot be further compressed, and the piston 1 stops moving. When the piston 1 moves toward the working chamber 1 22, the piston 2 limit plate 19 is reset under the action of the piston 2 limit plate spring 20. When the piston 2 3 moves toward the working chamber 2 24, the piston 1 limit plate 17 is reset under the action of the piston 1 limit plate spring 18. The opening speed, closing speed, opening sequence, closing sequence and opening and closing frequency of the control valve 1 13, the control valve 2 14, the control valve 3 15 and the control valve 4 16 are controllable.

[0024] like Figure 3 As shown, the control valve driving principle of the reverse osmosis system energy recovery device may include a motor 50, a worm 51, a worm wheel 52, a drive shaft 53, a cam 54, a cam 55, a cam 3, a cam 4, a cam 57, a driving cam 1 push rod 58, a cam 2 push rod 59, a cam 3 push rod 60 and a cam 4 push rod 61, wherein the motor 50 rotates to drive the worm 51 to rotate, drives the worm wheel 52 to rotate, the drive shaft 53 and the worm wheel 52 are fixed together to rotate synchronously, the cam 1 54, the cam 2 55, the cam 3 56, the cam 4 57 are fixed together with the drive shaft 53 to rotate synchronously, drives the cam 1 push rod 58, the cam 2 push rod 59, the cam 3 push rod 60, and the cam 4 push rod 61, cooperates with their respective push rod return springs, drives the control valve 13, the control valve 2 14, the control valve 4 16 and the control valve 3 15 to open and close.

[0025] When control valve three 15 and control valve two 14 are opened, control valve one 13 and control valve four 16 are closed. When control valve three 15 and control valve two 14 are closed, control valve one 13 and control valve four 16 are opened. For every rotation of the drive shaft, the switching of the control valve completes a cycle, and piston one 1 and piston two 3 complete a reciprocating motion.

[0026] Adjusting the opening speed of control valve 1 13, control valve 2 14, control valve 3 15 and control valve 4 16 to make the opening speed slow can reduce the impact caused by the instantaneous connection of high and low pressure media. The principle is that when high and low pressure media are connected, due to the compressibility of the media, the high pressure medium will instantly rush to the low pressure medium until the pressure is balanced. However, when the control valve opening speed is slow, the passage when the control valve is opened is very small, which will inhibit the flow rate of the high pressure medium to the low pressure medium, so that the pressure of the low pressure medium increases gradually instead of instantly, thereby reducing the impact and making the operation smoother.

[0027] Adjusting the closing speed of control valve 1 13, control valve 2 14, control valve 3 15 and control valve 4 16 to make the closing speed slow can reduce the impact of the control valve core on the valve seat when the control valve is closed, thereby extending the service life of the control valve.

[0028] The piston limit device is a flexible mechanism. When the piston limit plate seals the outlet of the working chamber, the piston can still compress the piston limit plate spring to continue moving. The flexible mechanism can reduce impact and vibration and make the operation smoother.

[0029] When piston 1 moves toward working chamber 122 under the pressure of the medium to be recovered, the volume of working chamber 122 is compressed, and the medium to be pressurized in working chamber 122 is discharged into the medium outlet 6 to be pressurized through one-way valve 28. Piston 23 moves synchronously with piston 1, and the volume of working chamber 24 increases with the movement of piston 23. The medium to be pressurized enters working chamber 24 through one-way valve 39. The pressure of working chamber 24 is substantially equal to the inlet pressure of the medium to be pressurized (when the medium to be pressurized passes through one-way valve 39, the pressure is slightly lost). This pressure generates thrust on piston 23. When this thrust plus the thrust generated by the pressure of the medium to be recovered on piston 1 is greater than the thrust required to drive piston 1 (the thrust required to drive piston 1 is mainly related to the pressure in working chamber 22), the energy recovery device can operate automatically without the need for an additional booster pump.

[0030] If the inlet pressure of the pressurized medium is sufficient, or an additional booster pump is configured so that the piston can move to the position where the piston is limited in each working stroke, then the piston moves a certain distance (one full stroke reciprocating) for each rotation of the drive shaft 53. The flow rate of the recovered medium is only related to the rotation speed of the drive shaft 53. The flow rate of the recovered medium can be adjusted by adjusting the frequency of the motor 50.

[0031] The cam tappet mechanism is used to drive the control valve, which is a purely mechanical structure with a simple and reliable structure. The opening speed, closing speed, opening sequence, and closing sequence of the control valve can be conveniently adjusted by adjusting the contour of the cam and the position of the cam on the drive shaft 53. The opening and closing frequency of the control valve can be conveniently adjusted by adjusting the frequency of the motor 50.

[0032] When the control valve 1 13 and the control valve 4 16 are in the closed state, and the cam tappet mechanism drives the control valve 3 15 and the control valve 2 14 to open, if the control valve 2 14 is driven to open first and the control valve 3 15 is opened later, the pressure difference between the two sides of the piston 1 and the piston 2 3 is small, which is beneficial to the force on the piston. On the contrary, if the control valve 3 15 is driven to open first and the control valve 2 14 is not opened at this time, the recovery chamber 1 23 has no outlet and the volume cannot be compressed. The pressures of the two recovery chambers are both high pressures transmitted by the pressurized medium, and the pressures of the two working chambers are both low pressures at the inlet of the pressurized medium. The pressure difference between the two sides of the piston is large, which is not beneficial to the force on the piston. Similarly, when the control valve 3 15 and the control valve 2 14 are closed, the control valve 3 15 is closed first and the control valve 2 14 is closed later, which is beneficial to the force on the piston. The opening and closing sequences of the control valve 1 13 and the control valve 4 16 are the same.

[0033] The present invention uses four control valves to switch the inlet and outlet of the medium to be recovered. The control valves do not generate obvious impact when working, and the operation is stable. The control valves have a long service life. The piston has a self-limiting function to prevent collision. When the inlet pressure of the pressurized medium is sufficient, a booster pump is not required. When specific conditions are met, the flow rate of the recovered medium can be conveniently adjusted. The present invention drives the opening and closing of the control valve through a cam tappet mechanism, and the structure is simple and reliable.

[0034] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A reverse osmosis system energy recovery device, characterized in that: The invention comprises a piston 1 (1), a piston 1 cylinder body (2), a piston 2 (3), a piston 2 cylinder body (4), an inlet (5) of a medium to be pressurized, an outlet (6) of a medium to be pressurized, a one-way valve 1 (7), a one-way valve 2 (8), a one-way valve 3 (9), a one-way valve 4 (10), an inlet (11) of a medium to be recovered, an outlet (12) of a medium to be recovered, a control valve 1 (13), a control valve 2 (14), a control valve 3 (15), a control valve 4 (16), a piston 1 limit plate (17), a piston 1 limit plate spring (18), a piston 2 limit plate (19), a piston 2 limit plate spring (20), a piston rod (21), a working chamber 1 (22), a recovery chamber 1 (23), a working chamber 2 (24) and a recovery chamber 2 (25), wherein the The piston 1 (1) and the piston 2 (3) are fixed on the piston rod (21); the piston 1 cylinder body (2) is divided by the piston 1 (1) into two chambers, namely the working chamber 1 (22) and the recovery chamber 1 (23); the inlet (5) of the medium to be pressurized is in one-way communication with the working chamber 1 (22) through the one-way valve 1 (7); the working chamber 1 (22) is in one-way communication with the outlet (6) of the medium to be pressurized through the one-way valve 2 (8); the recovery chamber 1 (23) is in one-way communication with the inlet (11) of the medium to be recovered through the control valve 1 (13); the recovery chamber 1 (23) is in one-way communication with the outlet (12) of the medium to be recovered through the control valve 2 (14); the piston 2 cylinder body (4) The second piston (3) is divided into two chambers, namely the second working chamber (24) and the second recovery chamber (25); the inlet (5) of the medium to be pressurized is in one-way communication with the second working chamber (24) through the third one-way valve (9); the second working chamber (24) is in one-way communication with the outlet (6) of the medium to be pressurized through the fourth one-way valve (10); the second recovery chamber (25) is in one-way communication with the inlet (11) of the medium to be recovered through the third control valve (15); the second recovery chamber (25) is in one-way communication with the outlet (12) of the medium to be recovered through the fourth control valve (16); the first piston limit plate (17) is arranged in the first working chamber (22); the first piston limit plate spring (18) is arranged on the first piston The piston 2 limit plate (19) is arranged in the working chamber 2 (24) between the limit plate (17) and the piston 1 (1), and the piston 2 limit plate spring (20) is arranged between the piston 2 limit plate (19) and the piston 2 (3). When the control valve 3 (15) and the control valve 2 (14) are opened, the control valve 1 (13) and the control valve 4 (16) are closed, the recovery chamber 2 (25) is connected to the inlet (11) of the medium to be recovered, and the recovery chamber 1 (23) is connected to the outlet (12) of the medium to be recovered. Under the pressure of the medium to be recovered, the piston 2 (3) moves toward the working chamber 2 (24), and the volume of the working chamber 2 (24) is compressed.The medium to be pressurized in the second working chamber (24) is discharged into the outlet (6) for the medium to be pressurized through the fourth one-way valve (10). The first piston (1) moves synchronously with the second piston (3). The volume of the first working chamber (22) increases with the movement of the first piston (1). The medium to be pressurized enters the first working chamber (22) through the first one-way valve (7). When the second piston limit plate (19) reaches a specified position, the second piston limit plate (19) seals the passage from the second working chamber (24) to the fourth one-way valve (10). The second working chamber (24) is closed. ) cannot be further compressed, the piston 2 (3) stops moving, the control valve 1 (13) and the control valve 4 (16) are opened, the control valve 3 (15) and the control valve 2 (14) are closed, the recovery chamber 1 (23) is connected to the inlet (11) of the medium to be recovered, the recovery chamber 2 (25) is connected to the outlet (12) of the medium to be recovered, and the piston 1 (1) moves toward the direction of the working chamber 1 (22) under the pressure of the medium to be recovered, the volume of the working chamber 1 (22) is compressed, and the pressurized medium in the working chamber 1 (22) is reduced. The medium to be pressurized passes through the one-way valve (8) and is discharged into the outlet (6) for the medium to be pressurized. The piston (2) (3) moves synchronously with the piston (1). The volume of the working chamber (24) increases with the movement of the piston (3). The medium to be pressurized passes through the one-way valve (9) and enters the working chamber (24). When the piston (1) limit plate (17) reaches a specified position, the piston (1) limit plate (17) seals the passage from the working chamber (22) to the one-way valve (8). The volume of the working chamber (22) cannot be further compressed. The piston (1) 1) Stop movement. When the piston 1 (1) moves toward the working chamber 1 (22), the piston 2 limit plate (19) is reset under the action of the piston 2 limit plate spring (20). When the piston 2 (3) moves toward the working chamber 2 (24), the piston 1 limit plate (17) is reset under the action of the piston 1 limit plate spring (18). The opening speed, closing speed, opening sequence, closing sequence and opening and closing frequency of the control valve 1 (13), the control valve 2 (14), the control valve 3 (15) and the control valve 4 (16) are controllable.

2. A reverse osmosis system energy recovery device according to claim 1, characterized in that: The control valve one (13), the control valve two (14), the control valve three (15) and the control valve four (16) are opened and closed by a cam tappet mechanism.

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