Fluid switching module and energy recovery device

Abstract

The fluid switching module comprises a valve body, a two-way connecting flange and a one-way connecting flange, a first cavity is formed in the left end of the valve body, the two-way connecting flange is fixed to the left side surface of the valve body, the two-way connecting flange communicates with the first cavity, and the one-way connecting flange is fixed to the left side surface of the valve body. A fixed sealing block is arranged between the two-way connecting flange and the valve body, a second cavity is formed in the upper end of the valve body, the one-way connecting flange is fixed to the surface of the upper end of the valve body, and the one-way connecting flange is communicated with the second cavity. A movable valve block for controlling the first cavity and the second cavity to be communicated and closed is arranged in the valve body, a power assembly is arranged on the side, away from the first cavity, of the movable valve block, and pressure parts are arranged on the two sides of the end, close to the first cavity, of the movable valve block. Self-tightening sealing can be achieved, and the sealing effect is improved.

Description

Technical Field

[0001] The invention relates to the technical field of seawater desalination energy recovery, in particular to a fluid switching module and an energy recovery device. Background Art

[0002] As one of the important components of the development and utilization of unconventional water resources, seawater desalination technology has become an important open-source measure to solve the shortage of freshwater resources. Reverse osmosis seawater desalination technology has developed rapidly due to its advantages such as short construction period, low investment cost and low energy consumption, and has been widely promoted and applied in coastal areas around the world. This technology belongs to the pressure-driven membrane separation process. The feed seawater pressure before the membrane needs to be increased to 5.5-6.0MPa by a high-pressure pump, and the fresh water recovery rate of the system is generally 40%-50%. In other words, 50%-60% of the feed before the membrane will become concentrated brine, and its pressure level is generally above 5.0MPa. If it is directly discharged through a pressure reducing valve, it will cause serious energy waste. The energy recovery device can pressurize the feed seawater by reusing the pressure energy in the concentrated brine to reduce the power consumption of the high-pressure pump, thereby significantly reducing the operating energy consumption of the reverse osmosis seawater desalination system.

[0003] Energy recovery devices are mainly divided into two types: centrifugal and positive displacement. The centrifugal device has a large single-unit processing capacity and good engineering magnification, but its pressure energy recovery process needs to undergo a two-step conversion of "pressure energy-shaft work-pressure energy", and the energy recovery efficiency generally does not exceed 80%. The positive displacement device adopts the Pascal isobaric transmission principle, which can directly transfer the pressure energy in the concentrated brine to the feed seawater, and the energy recovery efficiency is as high as more than 90%. The valve-controlled energy recovery device is a typical representative of the positive displacement device, which is generally composed of three parts: a switcher, a pressure exchange cylinder, and a check valve group. As the core component of the energy recovery device, the switcher controls the regular entry and exit of high-pressure concentrated brine and low-pressure brine in the pressure exchange cylinder. The pressure exchange cylinder is the main place for pressure exchange. The check valve group, as a passive actuator, cooperates with the switcher to complete the entry and exit of low-pressure feed seawater and high-pressure seawater in the pressure exchange cylinder. This type of device realizes the continuous recovery and utilization of the pressure energy of high-pressure concentrated brine through the coordinated work of the switcher, the pressure exchange cylinder, and the check valve group. For example, the Chinese patent application number CN201110268610.6 discloses a reciprocating slider axial sealing fluid switcher, which is opened and closed regularly by four coaxially connected sealing valve plates under the action of external driving force, so as to realize the periodic switching of the energy recovery process and the raw material filling process in the two pressure exchange cylinders matched with it. However, the shortcomings of this type of device are: the valve plate opening and closing process needs to overcome the pressure difference resistance on the entire area of ​​the inner and outer sides of the valve plate, and the driving load and driving energy consumption are large; the sealing when the valve plate is closed is a forced seal, and the sealing performance is poor under high pressure; a switcher is matched with two pressure exchange cylinders, and the processing and installation precision is high. Summary of the invention

[0004] The object of the present invention is to provide a fluid switching module and an energy recovery device, which have the characteristics of low load, low energy consumption, self-tightening sealing and simple installation.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a fluid switching module, comprising a valve body, a two-way connecting flange and a one-way connecting flange, a first cavity being opened at the left end of the valve body, the two-way connecting flange being fixed on the left side surface of the valve body, the two-way connecting flange being communicated with the first cavity, a fixed sealing block being arranged between the two-way connecting flange and the valve body, a second cavity being opened at the upper end of the valve body, the one-way connecting flange being fixed on the upper end surface of the valve body, the one-way connecting flange being communicated with the second cavity, a movable valve block for controlling the connection and closing between the first cavity and the second cavity being arranged in the valve body, a power assembly being arranged on the side of the movable valve block away from the first cavity, and pressure parts being arranged on both sides of the end of the movable valve block close to the first cavity.

[0006] Furthermore, the pressure portion is a boss fixed to the outer edge of the movable valve block.

[0007] Furthermore, pressure balancing holes are evenly distributed on the circumference of the movable valve block.

[0008] Furthermore, the power assembly includes an end cover and a connecting shaft. A sliding cavity that allows the movable valve block to slide is opened at a position on the valve body opposite to the two-way connecting flange. The end cover is fixed to the outside of the sliding cavity. The first connecting shaft is fixed to one end of the movable valve block away from the first cavity. The other end of the connecting shaft is connected to the second connecting shaft. The other end of the second connecting shaft passes through the end cover and is connected to the external driver.

[0009] Furthermore, the movable valve block, the sliding cavity, the second connecting shaft and the end cover are all provided with dynamic sealing components.

[0010] An energy recovery device comprises a pressure exchange cylinder, wherein the right side opening of the pressure exchange cylinder is connected to two fluid switching modules, the left side of the pressure exchange cylinder is connected to a low-pressure seawater jellyfish pipe and a high-pressure seawater jellyfish pipe through a second three-way water pipe, both the low-pressure seawater jellyfish pipe and the high-pressure seawater jellyfish pipe are provided with check valves, the left side of the pressure exchange cylinder is connected to a first three-way pipe, the other two pipe heads of the first three-way water pipe are respectively connected to the two-way connecting flange of the first fluid switching module and the one-way connecting flange of the second fluid switching module, the one-way connecting flange of the first fluid switching module is connected to the high-pressure salt jellyfish pipe, and the two-way connecting flange of the second fluid switching module is connected to the pressure relief salt jellyfish pipe.

[0011] The beneficial effects of the present invention are as follows: when the movable valve block is closed, the first cavity and the second cavity are respectively a low-pressure environment and a high-pressure environment, so the liquid pressure on the outer circumferential boss of the movable valve block can press the movable valve block and the fixed sealing block tightly. The greater the pressure in the second cavity, the better the sealing between the movable valve block and the fixed sealing block, thereby achieving a self-tightening seal and improving the sealing effect.

[0012] (2) The opening process of the movable valve block only needs to overcome the hydraulic pressure on the outer circumferential boss of the movable valve block rather than the hydraulic pressure on the entire area of ​​the movable valve block, so the driving load is low and the driving energy consumption is small.

[0013] (3) The connection between the fluid switching module and the pressure exchange cylinder is a single-cylinder connection, which reduces the processing and installation accuracy of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram when the fluid switching module is in a closed state;

[0015] Figure 2 It is a structural schematic diagram when the fluid switching module is in an open state;

[0016] Figure 3 A schematic diagram of the energy recovery process of the energy recovery device composed of the fluid switching module;

[0017] Figure 4 This is a schematic diagram of the raw material filling process of the energy recovery device composed of the fluid switching module.

[0018] Among them: 1-two-way connecting flange, 2-fixed sealing block, 3-movable valve block, 4-valve body, 5-second cavity, 6-one-way connecting flange, 7-first connecting shaft, 8-second connecting shaft, 9-first cavity, 10-pressure balance hole, 11-pressure part, 12-dynamic sealing assembly, 13-end cover, 14-external driver, 15-pressure exchange cylinder, 16-piston, 17-high-pressure sea jellyfish pipe, 18-low-pressure sea jellyfish pipe, 19-high-pressure salt jellyfish pipe, 20-pressure relief salt jellyfish pipe, 21-check valve, 22-module A, 23-module B, 24, sliding cavity. DETAILED DESCRIPTION

[0019] The present invention will be further described below in conjunction with the accompanying drawings.

[0020] See also Figures 1 to 4The present invention provides an embodiment: a fluid switching module, comprising a valve body 4, a two-way connecting flange 1 and a one-way connecting flange 6, the left end of the valve body 4 is provided with a first cavity 9, the two-way connecting flange 1 is fixed on the left side surface of the valve body 4, the two-way connecting flange 1 is communicated with the first cavity 9, a fixed sealing block 2 is arranged between the two-way connecting flange 1 and the valve body 4, a second cavity 5 is arranged at the upper end of the valve body 4, the one-way connecting flange 6 is fixed on the upper end surface of the valve body 4, the one-way connecting flange 6 is communicated with the second cavity 5, a movable valve block 3 for controlling the connection and closing between the first cavity 9 and the second cavity 5 is arranged in the valve body 4, a power assembly is arranged on the side of the movable valve block 3 away from the first cavity 9, and pressure parts 11 are arranged on both sides of the end of the movable valve block 3 close to the first cavity 9. The two-way connecting flange 1 is fixed to the left side of the valve body 4 by bolt connection, and the two-way connecting flange 1, the fixed sealing block 2 and the valve body 4 are pressed tightly; the one-way connecting flange 6 is fixed to the valve body 4 by welding; the movable valve block 3 slides left and right in the valve body 4 under the traction of the power component, so that the first cavity 9 and the second cavity 5 are connected or closed. When the movable valve block 3 is driven to move to the left under the traction of the power component so that the connection between the first cavity 9 and the second cavity 5 is closed, the pressure part 11 will be subjected to the pressure in the second cavity 5, so that the movable valve block 3 and the fixed sealing block 2 are pressed tightly to play a sealing role. When the first cavity 9 and the second cavity 5 need to be connected, it is only necessary to overcome the liquid pressure in the second cavity 5 on the pressure part 11.

[0021] Please continue reading Figure 1 , Figure 2 As shown, in one embodiment of the present invention, the pressure portion 11 is a boss fixed to the outer edge of the movable valve block 3. When the movable valve block 3 moves to the left to close the passage between the first cavity 9 and the second cavity 5, the second cavity 5 is a high-pressure cavity and the first cavity 9 is a low-pressure cavity. At this time, the force required for the movable valve block 3 to seal is the liquid pressure of the second cavity 5 on the boss area on the movable valve block 3. The greater the pressure of the second cavity 5, the greater the force, so that it can play a self-tightening sealing role. When the movable valve block 3 needs to be opened to connect the first cavity 9 and the second cavity 5, the external force at the shaft end only needs to overcome the liquid pressure of the second cavity 5 on the boss area. The load is not large and the driving energy consumption is small. The width of the boss is related to the pressure of the second cavity 5, the diameter of the movable valve block 3, and the clamping area between the movable valve block 3 and the fixed sealing block 2. It needs to be designed according to the specific situation.

[0022] Please continue reading Figure 1 , Figure 2As shown, in one embodiment of the present invention, the movable valve block 3 is provided with pressure balancing holes 10 evenly distributed around the circumference. The function of the pressure balancing hole 10 is to connect the first cavity 9 on the left side of the movable valve block 3 with the sliding cavity 24 on the right side of the movable valve block 3. On the one hand, it can avoid the occurrence of dead space in the sliding cavity 24 on the right side of the movable valve block 3, and on the other hand, it can balance the liquid pressure on the left and right end faces of the movable valve block 3, so that the sealing pressing force between the movable valve block 3 and the fixed sealing block 2 is proportional to the liquid pressure on the outer edge boss of the movable valve block 3. The greater the pressure of the second cavity 5, the greater the liquid pressure on the outer edge boss of the movable valve block 3, the greater the sealing pressing force between the movable valve block 3 and the fixed sealing block 2, and the better the sealing effect, so it has a self-tightening sealing characteristic, which is also one of the beneficial effects. In addition, due to the existence of the pressure balance hole 10 and its above-mentioned function, when the movable valve block 3 needs to move to the right to open, it only needs to overcome the liquid pressure on the outer edge boss of the movable valve block 3, and does not need to overcome the liquid pressure on the entire cross-section of the movable valve block 3 as in patent CN201110268610.6. Therefore, the load of the driver is smaller, which has a beneficial effect.

[0023] Please continue reading Figure 1 , Figure 2 As shown, in one embodiment of the present invention, the power assembly includes an end cover 13 and a connecting shaft, a sliding cavity 24 is provided on the valve body 4 at a position opposite to the two-way connecting flange 1, and the end cover 13 is fixed to the outside of the sliding cavity 24, the first connecting shaft 7 is fixed to one end of the mobile valve block 3 away from the first cavity 9, the other end of the connecting shaft is connected to the second connecting shaft 8, and the other end of the second connecting shaft 8 passes through the end cover 13 and is connected to the external driver 14. One end of the first connecting shaft 7 is connected to the mobile valve block 3 by a thread, and the other end of the first connecting shaft 7 is connected to one end of the second connecting shaft 8 by a thread, and the other end of the second connecting shaft 8 extends out of the end cover 13 and is connected to the external driver 14. The external driver 14 can drive the second connecting shaft 8 to move left or right, thereby moving the movable valve block 3 to move left or right, realizing the connection and closing of the first cavity 9 and the second cavity 5. At the same time, the external driver 14 also provides power to overcome the hydraulic pressure on the pressure part 11. The external driver 14 can be a telescopic cylinder, a hydraulic cylinder, or an electric cylinder.

[0024] Please continue reading Figure 1 , Figure 2 As shown, in one embodiment of the present invention, a dynamic seal assembly 12 is provided on the movable valve block 3, the sliding cavity 24, the second connecting shaft 8, and the end cover 13. The dynamic seal assembly 12 is a common seal that prevents the medium in the valve from leaking as the movable valve block 3 and the connecting shaft move.

[0025] Please continue reading Figure 3 , Figure 4As shown, the present invention provides an embodiment: an energy recovery device, comprising a pressure exchange cylinder 15, the right side of the pressure exchange cylinder 15 is connected to two fluid switching modules, the left side of the pressure exchange cylinder 15 is connected to a low-pressure seawater jellyfish pipe 18 and a high-pressure seawater jellyfish pipe 17 through a second three-way water pipe, and the low-pressure seawater jellyfish pipe 18 and the high-pressure seawater jellyfish pipe 17 are both provided with a check valve 21, and the left side of the pressure exchange cylinder 15 is connected to a first three-way pipeline, and the other two pipe heads of the first three-way water pipe are respectively connected to the two-way connection flange 1 of the first fluid switching module and the one-way connection flange 6 of the second fluid switching module, the one-way connection flange 6 of the first fluid switching module is connected to the high-pressure salt jellyfish pipe 19, and the two-way connection flange 1 of the second fluid switching module is connected to the pressure relief salt jellyfish pipe 20. The second connecting shaft 8 of the fluid switching module is connected to the external external driver 14, and the movable valve block 3 slides left and right in the second cavity 5 of the valve body 4 under the traction of the external driver 14, so that the fluid switching module is opened (such as Figure 2 as shown) or off (as shown Figure 1 Two fluid switching modules (hereinafter referred to as module A22 and module B23), a pressure exchange cylinder and a check valve 21 constitute an energy recovery device, as shown in FIG. Figure 3 , Figure 4 As shown, the one-way connecting flange 6 of module A22 is connected to the high-pressure salt jellyfish pipe 19, the two-way connecting flange 1 of module A22 is connected to the pressure exchange cylinder, the two-way connecting flange 1 of module B23 is connected to the pressure relief salt jellyfish pipe 20, and the one-way connecting flange 6 of module B23 is connected to the pressure exchange cylinder.

[0026] The present invention has the following working principle: when module A22 is in the open state (such as Figure 2 As shown), module B23 is in the closed state (as shown Figure 1 As shown), the energy recovery process is carried out in the pressure exchange cylinder of the energy recovery device unit (as shown Figure 3 At this time, the high-pressure concentrated brine discharged from the RO membrane assembly flows through the one-way connection flange 6 of module A22, the second cavity 5 in the valve body 4, the second connection shaft 9 in the fixed sealing block 2, and the two-way connection flange 1 in turn to enter the pressure exchange cylinder, pushing the piston 16 in the pressure exchange cylinder to move to the left, and using the Pascal isobaric transmission principle to transfer the pressure energy of the high-pressure concentrated brine to the low-pressure fresh seawater on the left side of the piston 16. The pressurized fresh seawater is collected into the high-pressure seawater jelly pipe 17 through the check valve 21, and then enters the RO membrane assembly to produce water. When the piston 16 in the pressure exchange cylinder moves to the left side of the pressure exchange cylinder, module A22 is closed first (as shown in FIG. 1 ). Figure 1 As shown), module B23 is opened again (as shown Figure 2 As shown), the pressure exchange cylinder of the energy recovery device unit is switched from the energy recovery process to the raw material filling process.

[0027] Figure 4 This is the raw material filling process of the energy recovery device unit. At this time, fresh low-pressure feed seawater enters the pressure exchange cylinder through the low-pressure seawater jelly pipe 18 and the check valve 21, pushing the piston 16 to move to the right, so that the low-pressure concentrated brine that completes the pressure exchange on the right side of the piston 16 enters the pressure relief brine jelly pipe 20 for discharge through the one-way connection flange 6 of the module B23, the second cavity 5 in the valve body, the second connection shaft 9 in the fixed sealing block 2, and the two-way connection flange 1. When the piston 16 in the pressure exchange cylinder moves to the right side of the pressure exchange cylinder, the module B23 is closed first (such as Figure 1 As shown), module A22 is turned on again (as shown Figure 2 As shown), the pressure exchange cylinder of the energy recovery device unit is switched from the raw material filling process to the energy recovery process.

[0028] The above description is only a preferred embodiment of the present invention and should not be construed as limiting the present application. All equivalent changes and modifications made within the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A fluid switching module, characterized in that: The valve body comprises a valve body, a two-way connecting flange and a one-way connecting flange, a first cavity is opened at the left end of the valve body, the two-way connecting flange is fixed on the left side surface of the valve body, the two-way connecting flange is communicated with the first cavity, a fixed sealing block is arranged between the two-way connecting flange and the valve body, a second cavity is opened at the upper end of the valve body, the one-way connecting flange is fixed on the upper end surface of the valve body, the one-way connecting flange is communicated with the second cavity, a movable valve block for controlling the connection and closing between the first cavity and the second cavity is arranged in the valve body, a power assembly is arranged on the side of the movable valve block away from the first cavity, and pressure parts are arranged on both sides of the end of the movable valve block close to the first cavity.

2. A fluid switching module according to claim 1, characterized in that: The pressure portion is a boss fixed on the outer edge of the movable valve block.

3. A fluid switching module according to claim 1, characterized in that: The movable valve block is provided with pressure balancing holes evenly distributed on its circumference.

4. A fluid switching module according to claim 1, characterized in that: The power assembly includes an end cover and a connecting shaft. A sliding cavity that allows the movable valve block to slide is opened at a position on the valve body opposite to the two-way connecting flange. The end cover is fixed to the outside of the sliding cavity. The first connecting shaft is fixed to one end of the movable valve block away from the first cavity. The other end of the connecting shaft is connected to the second connecting shaft. The other end of the second connecting shaft passes through the end cover and is connected to an external driver.

5. A fluid switching module according to claim 4, characterized in that: The movable valve block, the sliding cavity, the second connecting shaft and the end cover are all provided with dynamic sealing components.

6. An energy recovery device, characterized in that: it includes a pressure exchange cylinder, the right side opening of the pressure exchange cylinder is connected to two fluid switching modules as described in claim 1, the left side of the pressure exchange cylinder is connected to a low-pressure seawater jellyfish pipe and a high-pressure seawater jellyfish pipe through a second three-way water pipe, and both the low-pressure seawater jellyfish pipe and the high-pressure seawater jellyfish pipe are provided with check valves, the left side of the pressure exchange cylinder is connected to a first three-way pipe, the other two pipe heads of the first three-way water pipe are respectively connected to the two-way connecting flange of the first fluid switching module and the one-way connecting flange of the second fluid switching module, the one-way connecting flange of the first fluid switching module is connected to the high-pressure salt jellyfish pipe, and the two-way connecting flange of the second fluid switching module is connected to the pressure relief salt jellyfish pipe.

Images