A filter cartridge assembly with high recovery

Abstract

The application relates to a filter core device with high recovery rate, and relates to the field of filtering devices.The filter core device comprises a filter core shell, a first RO membrane element and a second RO membrane element, the first RO membrane element and the second RO membrane element are arranged in a sleeved mode, the flux of the first RO membrane element is greater than that of the second RO membrane element; the filter core shell is provided with a first water channel, a second water channel and a third water channel, the first water channel comprises, in sequence along a flow direction, an original water inlet, an original water cavity, the first RO membrane element, a first clean water cavity, a clean water outlet; the second water channel comprises, in sequence along the flow direction, the original water inlet, the original water cavity, the first RO membrane element, a first waste water cavity, the second RO membrane element, a second clean water cavity and the clean water outlet; and the third water channel comprises, in sequence along the flow direction, the original water inlet, the original water cavity, the first RO membrane element, the first waste water cavity, the second RO membrane element, a second waste water cavity and a waste water outlet.The application can improve the waste water recovery rate.

Description

Technical Field

[0001] This application relates to the field of filtration devices, and more particularly to a filter cartridge device with a high recovery rate. Background Technology

[0002] With the increasing popularity of water purifiers, the number of users is also gradually increasing. Existing filter devices include a housing, an RO membrane element, and a central tube. The RO membrane element includes an inlet screen, a membrane sheet, and a product water screen. The RO membrane element is wound around the outside of the central tube. The housing has a raw water inlet, a wastewater inlet, and a purified water inlet, with the purified water inlet connected to the central tube. Raw water enters through the raw water inlet, and as it passes through the RO membrane element, purified water enters the central tube through osmosis and exits through the purified water inlet. Unfiltered wastewater continues to flow and is discharged through the wastewater inlet.

[0003] To increase the water output of a water purifier, high-flux RO membrane elements are often used. Flux refers to the amount of water passing through a unit area of ​​the RO membrane per unit time.

[0004] Existing filter cartridge devices often generate a large amount of wastewater, meaning that a large amount of wastewater is not filtered, resulting in a low recovery rate. The recovery rate is equal to the net water volume / the raw water volume * 100%. The main reason is that increasing the recovery rate often damages the lifespan of the RO membrane. The specific analysis is as follows: There are two existing ways to improve the recovery rate. The first is to increase the pressure of the raw water. Increasing the pressure will improve the efficiency of the RO membrane in filtering wastewater, thereby increasing the recovery rate. However, under high pressure, the squeezing force between the inlet screen, membrane, and product water screen will be greater, leading to damage to the membrane structure.

[0005] The second approach involves reducing both the wastewater discharge and the raw water intake. When a small amount of raw water comes into contact with a high-flux RO membrane element for filtration, more purified water can be filtered out due to the high flux of the RO membrane element. According to the recovery rate calculation formula, when the raw water is reduced and the purified water volume remains within a certain range, the recovery rate will increase accordingly. However, because a large amount of purified water is extracted from a small amount of raw water, the salt concentration in the raw water increases significantly, leading to the rapid formation of a large amount of crystals that clog the RO membrane element. This affects the flux and lifespan of the RO membrane element, and long-term use will also affect the recovery rate. Summary of the Invention

[0006] In order to improve the recovery rate while ensuring service life, this application provides a filter cartridge device with a high recovery rate.

[0007] This application provides a filter cartridge device with a high recovery rate, which adopts the following technical solution:

[0008] A high-recovery-rate filter cartridge device includes a filter cartridge housing, a first RO membrane element, and a second RO membrane element, which are nested together. The flux of the first RO membrane element is greater than that of the second RO membrane element. The filter cartridge housing has a raw water inlet, a clean water inlet, a wastewater inlet, a raw water chamber, a first wastewater chamber, a first clean water chamber, a second wastewater chamber, and a second clean water chamber. The filter cartridge housing also has a first water path, a second water path, and a third water path. The first water path sequentially includes the raw water inlet, the raw water chamber, the first RO membrane element, the first clean water chamber, and the clean water inlet along the flow direction. The second water path sequentially includes the raw water inlet, the raw water chamber, the first RO membrane element, the first wastewater chamber, the second RO membrane element, the second clean water chamber, and the clean water inlet along the flow direction. The third water path sequentially includes the raw water inlet, the raw water chamber, the first RO membrane element, the first wastewater chamber, the second RO membrane element, the second wastewater chamber, and the wastewater inlet along the flow direction.

[0009] By adopting the above technical solution, and by setting up a high-flux first RO membrane element and a low-flux second RO membrane element, and defining three water paths, the movement path of wastewater is limited and its length is extended. This allows the high-concentration primary wastewater that has passed through the first RO membrane element to pass through the second RO membrane element for secondary filtration. Since the second RO membrane element has a smaller flux, it filters only a portion of the purified water, thereby improving the recovery rate. Furthermore, it keeps the salt concentration of the secondary wastewater within a certain range, meaning the concentration of the secondary wastewater is not high, which reduces the formation of crystals in the second RO membrane element and thus takes into account its service life.

[0010] Secondly, by setting the relative positions of the high-flow first RO membrane element and the low-flow second RO membrane element, the direction of the water path is correspondingly defined, which means that the primary filtration of raw water and the secondary filtration of wastewater can be completed in the same filter element device. The structure is simplified and more suitable for the working conditions of household water purifiers.

[0011] In summary, under the same operating conditions as existing technologies—namely, conventional raw water volume and pressure—this technical solution, by setting up a high-flux first RO membrane element and a low-flux second RO membrane element, and limiting the three water paths, allows a significant amount of primary wastewater to be filtered out again by the low-flux second RO membrane element, thus improving the recovery rate. Furthermore, it keeps the salt concentration of the secondary concentrate within a certain range, preventing excessively high concentrations that could lead to crystallization or excessively rapid crystallization. This greatly ensures service life and operational stability, such as maintaining stable flux and desalination rate. Secondly, it also features a simplified structure, making it more suitable for household water purifiers.

[0012] Optionally, the desalination rate of the second RO membrane element is greater than or equal to the desalination rate of the first RO membrane element.

[0013] Optionally, the water inlet method of the first RO membrane element is peripheral water inlet and / or end face water inlet.

[0014] Optionally, it also includes an inner membrane shell, a first central tube, and a second central tube. Both the first and second central tubes have through holes. The first RO membrane element is wound around the first central tube, and the second RO membrane element is wound around the second central tube. The inner membrane shell is sleeved on the outer periphery of the second RO membrane element, and the first central tube is sleeved on the outer periphery of the inner membrane shell. An annular first purified water cavity is formed between the inner peripheral wall of the first central tube and the outer peripheral wall of the inner membrane shell, and the inner cavity of the second central tube is the second purified water cavity.

[0015] Optionally, it also includes a first sealing structure, a second sealing structure, and a first mounting end cap. The annular gap between the outer peripheral surface of the first RO membrane element and the inner peripheral surface of the filter cartridge housing forms the raw water chamber. One end of the first central tube is provided with a first end cap, and one end of the inner membrane shell is provided with a second end cap. The axial gap between the first end cap and the second end cap forms a manifold. The first purified water chamber and the second purified water chamber are connected through the manifold. The first end cap has a first water pipe, and the manifold is connected to the purified water outlet through the first water pipe. The first mounting end cap is installed on the end of the second central tube away from the second end cap. The axial gap between the first mounting end cap and the end face of the first RO membrane element and the end face of the second RO membrane element is set to... The first wastewater chamber has a retaining ring on the outer edge of the first mounting end cap, which overlaps the outer periphery of the first RO membrane element and separates the raw water chamber from the first wastewater chamber. The second sealing structure is disposed in the gap between the first central tube and the inner membrane shell at the end away from the second end cap, and separates the first wastewater chamber from the first clean water chamber. The second wastewater chamber is formed by the first sealing structure, the end face of the first end cap, and the inner end face of one side of the filter element shell. The first sealing structure separates the second wastewater chamber from the raw water chamber. The wastewater outlet communicates with the second wastewater chamber. The second end cap has a second water pipe that passes through the manifold and the first end cap and communicates with the second wastewater chamber.

[0016] Optionally, the first sealing structure includes a connecting ring body, which is sleeved and installed on the outside of the first central tube. An annular side baffle, an annular connecting part, and an annular sealing part are integrally formed on the outer diameter of the connecting ring body. The side baffle fits against the end face of the first RO membrane element, and the sealing part seals against the inner peripheral wall of the filter element housing.

[0017] Optionally, the first sealing structure includes a connecting ring body, which is sleeved and installed on the outside of the first central tube. An annular side baffle, an annular connecting part, and an annular sealing part are integrally formed on the outer diameter of the connecting ring body. The gap between the side baffle and the end face of the first RO membrane element communicates with the raw water cavity. The sealing part seals against the inner peripheral wall of the filter element housing. The outer peripheral surface of the first RO membrane element is wrapped with tape.

[0018] Optionally, it also includes an inner membrane shell, a first central tube, and a second central tube. Both the first and second central tubes have through holes. The first RO membrane element is wound around the first central tube, and the second RO membrane element is wound around the second central tube. The inner membrane shell is sleeved on the outer periphery of the first RO membrane element, and the second central tube is sleeved on the outer periphery of the inner membrane shell. An annular second purified water cavity is formed between the inner peripheral wall of the second central tube and the outer peripheral wall of the inner membrane shell. The inner cavity of the first central tube is the first purified water cavity.

[0019] Optionally, it also includes a first sealing structure, a second sealing structure, and a first mounting end cap. The annular gap between the outer peripheral surface of the second RO membrane element and the inner peripheral surface of the filter cartridge housing forms the second wastewater chamber, and the wastewater outlet communicates with the second wastewater chamber. One end of the second central tube is provided with a third end cap, and one end of the inner membrane shell is provided with a second end cap. The first sealing structure, the end face of the third end cap, and one inner end face of the filter cartridge housing together form the raw water chamber. The first sealing structure separates the second wastewater chamber and the raw water chamber. The first end cap has a first water pipe that passes through the third end cap and communicates with the raw water chamber. The third end cap has a third water pipe, and the axial distance between the first end cap and the third end cap is... A manifold is formed by the gap, and the first purified water chamber and the second purified water chamber are connected through the manifold. The manifold is connected to the purified water outlet through a third water pipe. The first mounting end cap is installed at the end of the first central tube away from the second end cap. The axial gap between the first mounting end cap and the end face of the first RO membrane element and the end face of the second RO membrane element is set as the first wastewater chamber. A retaining ring is provided on the outer edge of the first mounting end cap. The retaining ring overlaps the outer peripheral side of the first RO membrane element and separates the first wastewater chamber and the second wastewater chamber. The second sealing structure is set in the gap between the second central tube and the end of the inner membrane shell away from the second end cap. The second sealing structure separates the first wastewater chamber and the first purified water chamber.

[0020] Optionally, it also includes a movable ring plate, a fixed ring plate, a telescopic tube, a motor, a spring, a fixed sleeve, and a movable sleeve. The fixed sleeve is sleeved and fixed to the outer periphery of the first RO membrane element and is densely covered with first water holes. The movable sleeve is axially slidably sleeved to the outer periphery of the fixed sleeve and is densely covered with second water holes. The movable ring plate is axially slidably disposed with respect to the inner wall of the filter element housing, and a transfer cavity is formed between the movable ring plate and the first sealing structure. The movable ring plate separates the raw water cavity and the transfer cavity. One end of the movable sleeve is fixed to the movable ring plate. The cylinder has a third water hole at one end. The spring force is used to force the moving ring plate to move away from the first sealing structure. The outer peripheral wall of the fixed ring plate is coaxially fixed with the inner wall of the filter element housing. The two ends of the telescopic tube are respectively fixed to the moving ring plate and the fixed ring plate. The fixed ring plate, the moving ring plate, the inner wall of the filter element housing and the outer wall of the telescopic tube together enclose the pressurization chamber. The fixed ring plate is provided with a first one-way valve and the moving ring plate is provided with a second one-way valve. The output shaft of the motor is provided with a cam. The cam abuts against the side of the moving ring plate. The motor is used to maintain the position of the cam or drive the cam to rotate continuously.

[0021] In summary, this application includes at least one of the following beneficial technical effects:

[0022] 1. Under normal raw water volume and pressure conditions, by setting up a high-flow-rate first RO membrane element and a low-flow-rate second RO membrane element, and limiting three water paths, a significant amount of primary wastewater is filtered out by the low-flow-rate second RO membrane element, thereby improving the recovery rate. Furthermore, the salt concentration of the secondary concentrate is controlled within a certain range, preventing excessively high concentrations that could lead to crystal formation or excessively rapid crystal formation. This greatly ensures service life and operational stability, such as maintaining stable flux and desalination rate. Secondly, it also features a simplified structure, making it more suitable for household water purifiers. Attached Figure Description

[0023] Figure 1 This is a cross-sectional view of the filter cartridge device of Example 1.

[0024] Figure 2 This is a partial enlarged view of the end of the filter element device in Example 1.

[0025] Figure 3 This is a schematic block diagram of the three waterways in Example 1.

[0026] Figure 4 This is a cross-sectional view of the filter cartridge device of Example 1.

[0027] Figure 5 This is a schematic diagram of Example 1 illustrating the water inlet method at the end face of the first RO membrane element.

[0028] Figure 6 This is a cross-sectional view of the filter cartridge device of Example 2.

[0029] Figure 7 This is a cross-sectional view of the filter cartridge device of Example 3.

[0030] Figure 8 This is a partial enlarged view of the end of the filter element device in Example 3.

[0031] Figure 9 This is a partial enlarged view of the end of the filter element device in Example 4.

[0032] Figure 10 This is a schematic diagram of Example 4 illustrating that the pressurization chamber is in a contracted state.

[0033] Figure 11 This is a schematic diagram of Example 4 illustrating the pressurized chamber in an expanded state.

[0034] Explanation of reference numerals in the attached drawings: 1. First RO membrane element; 2. Second RO membrane element; 3. Inner membrane shell; 5. First sealing structure; 6. Second sealing structure; 10. Through hole; 100. Filter cartridge shell; 101. Raw water inlet; 102. Wastewater inlet; 103. Clean water inlet; 110. Raw water chamber; 111. First wastewater chamber; 112. First clean water chamber; 113. Second wastewater chamber; 115. Second clean water chamber; 116. Manifold; 117. First mounting end cap; 118. Retaining ring; 119. Second mounting end cap; 120. Fourth water pipe; 121. Third clean water chamber; 122. Drain hole; 123. Transfer chamber; 124. 11. Pressurization chamber; 12. First central tube; 13. First end cap; 24. First water pipe; 25. Second central tube; 26. Third end cap; 27. Third water pipe; 38. Second end cap; 39. Second water pipe; 20. Second end cap; 30. Second water pipe; 21. Connecting ring body; 51. Convex ring; 51. Ring groove; 52. Side stop; 53. Connecting part; 54. Sealing part; 75. Moving ring plate; 76. Fixed ring plate; 77. Telescopic tube; 78. Motor; 79. Spring; 80. Fixed sleeve; 71. Moving sleeve; 81. First water hole; 82. Second water hole; 83. Third water hole; 84. Cam; 85. First check valve; 86. Second check valve. Detailed Implementation

[0035] The following is in conjunction with the appendix Figure 1 - Appendix Figure 11 This application will be described in further detail.

[0036] Example 1

[0037] Example 1 discloses a filter cartridge device with a high recovery rate. (Refer to...) Figure 1 and Figure 2 ( Figure 1(The solid arrows in the diagram indicate the direction of raw water flow, the dashed arrows indicate the direction of wastewater flow, and the solid arrows indicate the direction of purified water flow.) The high-recovery-rate filter cartridge device includes a filter cartridge housing 100, a first RO membrane element 1, a second RO membrane element 2, an inner membrane housing 3, a first central tube 11, a second central tube 21, a first sealing structure 5, a second sealing structure 6, and a first mounting end cap 117. The first central tube 11 and the second central tube 21 both have through holes 10. The first RO membrane element 1 is wound around the first central tube 11, and the second RO membrane element 2 is wound around the second central tube 21. The first RO membrane element 1 and the second RO membrane element 2 are nested together. In this embodiment, the first RO membrane element 1 is located on the outer periphery of the second RO membrane element 2.

[0038] The flux of the first RO membrane element 1 is greater than that of the second RO membrane element 2. In this embodiment, the flux of the first RO membrane element 1 can be set to 400G, and the flux of the second RO membrane element 2 can be set to 100G.

[0039] The filter cartridge device has a raw water inlet 101, a clean water inlet 103, a waste water inlet 102, a raw water chamber 110, a first waste water chamber 111, a first clean water chamber 112, a second waste water chamber 113, and a second clean water chamber 115.

[0040] like Figure 3 As shown, the filter cartridge device has a first water path, a second water path and a third water path. The first water path includes, in sequence along the flow direction, a raw water inlet 101, a raw water chamber 110, a first RO membrane element 1, a through hole 10 of the first RO membrane element 1, a first purified water chamber 112 and a purified water inlet 103.

[0041] The second water channel includes, in sequence along the flow direction, a raw water inlet 101, a raw water chamber 110, a first RO membrane element 1, a through hole 10 of the first RO membrane element 1, a first wastewater chamber 111, a second RO membrane element 2, a through hole 10 of the second RO membrane element 2, a second purified water chamber 115, and a purified water inlet 103.

[0042] The third waterway includes, in sequence along the flow direction, a raw water inlet 101, a raw water chamber 110, a first RO membrane element 1, a first wastewater chamber 111, a second RO membrane element 2, a second wastewater chamber 113, and a wastewater inlet 102.

[0043] By setting up a high-flux first RO membrane element 1 and a low-flux second RO membrane element 2, and defining three water paths, the movement path of the wastewater is limited and its length is extended. This allows the high-concentration primary wastewater that has passed through the first RO membrane element 1 to pass through the second RO membrane element 2 for secondary filtration. Since the second RO membrane element 2 has a smaller flux, it only filters a portion of the purified water, thereby improving the recovery rate. Furthermore, it keeps the salt concentration of the secondary wastewater within a certain range, meaning the concentration of the secondary wastewater is not high, which reduces the formation of crystals in the second RO membrane element 2 and thus takes into account its service life.

[0044] Secondly, by setting the relative positions of the high-flow first RO membrane element 1 and the low-flow second RO membrane element 2, the direction of the water path is correspondingly defined, that is, the raw water primary filtration and wastewater secondary filtration can be completed in the same filter element device, the structure is simplified, and it is more suitable for the working conditions of household water purifiers.

[0045] In summary, under normal raw water volume and pressure conditions, the technical solution of this application, by setting up a high-flux first RO membrane element 1 and a low-flux second RO membrane element 2, and limiting three water paths, allows a significant amount of primary wastewater to be filtered out again by the low-flux second RO membrane element 2, thereby improving the recovery rate. Furthermore, it keeps the salt concentration of the secondary concentrate within a certain range, preventing excessively high concentrations that could lead to crystal formation or excessively rapid crystal formation. This greatly ensures the service life and operational stability, such as maintaining stable flux and desalination rate. Secondly, it also features a simplified structure, making it more suitable for household water purifiers.

[0046] Preferably, the desalination rate of the second RO membrane element 2 is greater than or equal to the desalination rate of the first RO membrane element 1. In this embodiment, the desalination rate of the second RO membrane element 2 is greater than the desalination rate of the first RO membrane element 1. For example, the desalination rate of the first RO membrane element 1 is 90%, and the desalination rate of the second RO membrane element 2 is 95%. This is mainly because the concentration of the primary wastewater is high, and an RO membrane element with a higher desalination rate is needed to obtain secondary purified water with a water quality similar to that of the primary purified water.

[0047] If the water quality requirements for comprehensive water purification are not high, the desalination rate of the second RO membrane element 2 can be equal to or less than the desalination rate of the first RO membrane element 1.

[0048] The specific structural configurations of the raw water inlet 101, purified water inlet 103, wastewater inlet 102, raw water chamber 110, first wastewater chamber 111, first purified water chamber 112, second wastewater chamber 113, and second purified water chamber 115 are as follows: Figure 1 , Figure 2 , Figure 4As shown, the raw water inlet 101 is located on the outer periphery of the filter element housing 100, and the purified water inlet 103 and wastewater inlet 102 are located at the same end of the filter element housing 100, wherein the purified water inlet 103 is located at the center of the end face of the filter element housing 100. The second central tube 21 is fixed at the axis of the filter element housing 100, and the inner cavity of the second central tube 21 is the second purified water chamber 115. The inner membrane shell 3 is sleeved on the outer periphery of the second RO membrane element 2. The first central tube 11 is coaxial with the filter element housing 100 and is sleeved on the outer periphery of the inner membrane shell 3. An annular first purified water chamber 112 is formed between the inner peripheral wall of the first central tube 11 and the outer peripheral wall of the inner membrane shell 3. The annular gap between the outer peripheral surface of the first RO membrane element 1 and the inner peripheral surface of the filter element housing 100 is the raw water chamber 110.

[0049] The first central tube 11 has a first end cap 12 integrally formed at one end near the water inlet 103, and the inner membrane shell 3 has a second end cap 31 integrally formed at one end near the water inlet 103. The axial gap between the first end cap 12 and the second end cap 31 forms a manifold 116. The second central tube 21 passes through the center of the second end cap 31 and enters the manifold 116. That is, the first water inlet 112 and the second water inlet 115 are connected through the manifold 116. The first end cap 12 has a first water pipe 13 at its center. The first water pipe 13 is connected to the water inlet 103. That is, the manifold 116 is connected to the water inlet 103 through the first water pipe 13.

[0050] The first mounting end cap 117 is installed at the end of the second central tube 21 away from the second end cap 31. The axial gap between the first mounting end cap 117 and the end face of the first RO membrane element 1 and the end face of the second RO membrane element 2 is set as the first wastewater chamber 111. A retaining ring 118 is integrally formed on the outer edge of the first mounting end cap 117. The retaining ring 118 overlaps the outer peripheral side of the first RO membrane element 1 and separates the raw water chamber 110 and the first wastewater chamber 111.

[0051] The second sealing structure 6 is disposed in the gap between the first central tube 11 and the inner membrane shell 3 at the end away from the first end cap 12. In this embodiment, the second sealing structure 6 is a sealing ring, and the second sealing structure 6 separates the first wastewater chamber 111 and the first clean water chamber 112.

[0052] The first sealing structure 5, the end face of the first end cap 12, and the inner end face of one side of the filter housing 100 enclose the second wastewater chamber 113. The first sealing structure 5 separates the second wastewater chamber 113 from the original water chamber 110. The eccentrically positioned wastewater outlet 102 communicates with the second wastewater chamber 113. The second end cap 31 has a second water pipe 32, which is eccentrically positioned to avoid the first water pipe 13. The second water pipe 32 passes through the manifold 116 and the first end cap 12 and communicates with the second wastewater chamber 113.

[0053] The water inlet method of the first RO membrane element 1 is peripheral water inlet and / or end face water inlet, depending on the specific water quality. In this embodiment, the water inlet method of the first RO membrane element 1 is peripheral water inlet. Specifically, the outer peripheral surface of the first RO membrane element 1 is wrapped with tape (not shown in the figure). The tape has holes. The first sealing structure 5 includes a connecting ring 51. The connecting ring 51 is made of rubber. The connecting ring 51 is sleeved and installed on the outside of the first central tube 11. The outer diameter of the connecting ring 51 is integrally formed with an annular side baffle 52, an annular connecting part 53 and an annular sealing part 54. The side baffle 52 fits the end face of the first RO membrane element 1. The cross section of the sealing part 54 is ">" shaped. The sealing part 54 seals against the inner peripheral wall of the filter element housing 100.

[0054] That is, the end face of the first RO membrane element 1 is sealed by the side baffle 52. The raw water enters the outer peripheral surface of the first RO membrane element 1 only through the holes of the tape. The peripheral water inlet method has a shorter water path and less water resistance, which is mainly suitable for raw water with high conductivity.

[0055] If the local water conductivity is low, an end-face water inlet method can also be used. Adjustments can be made during filter installation. Specifically, for example... Figure 5 As shown, the connecting ring 51 is installed on the outer side of the first central tube 11 in such a way that a convex ring 511 is integrally formed on the inner circumferential surface of the connecting ring 51, and two annular grooves 512 are provided on the outer side of the first central tube 11. The convex ring 511 cooperates with the two annular grooves 512 respectively to adjust the axial position of the connecting ring 51. That is, the connecting ring 51 has two axial positions. The first axial position is shown below. Figure 1 The side baffle 52 is attached to the end face of the first RO membrane element 1, i.e., the outer peripheral surface is inlet for water. The second axial position is shown below. Figure 5 There is a gap between the side baffle 52 and the end face of the first RO membrane element 1, that is, the end face of the first RO membrane element 1 is connected to the raw water chamber 110. At the same time, the tape covering the first RO membrane element 1 has no holes, that is, the outer peripheral surface of the first RO membrane element 1 is not in contact with the raw water in the raw water chamber 110, so that the raw water can only enter through the end face of the first RO membrane element 1. At this time, the water resistance is larger but the filtration effect is better.

[0056] Example 2

[0057] The difference between Example 2 and Example 1 is that, as Figure 6 As shown ( Figure 6(The solid arrows indicate the direction of raw water flow, the dashed arrows indicate the direction of wastewater flow, and the solid arrows indicate the direction of purified water flow.) The first central tube 11 is fixed at the axis of the filter element housing 100. The inner cavity of the first central tube 11 is the first purified water chamber 112. The inner membrane shell 3 is sleeved on the outer periphery of the first RO membrane element 1. The end of the first central tube 11 passes through the second end cap 31. The second central tube 21 is sleeved on the outer periphery of the inner membrane shell 3. The second central tube 21 is coaxially arranged with the filter element housing 100. An annular second purified water chamber 115 is formed between the inner peripheral wall of the second central tube 21 and the outer peripheral wall of the inner membrane shell 3. A third end cap 22 is integrally formed at one end of the second central tube 21. The axial gap between the third end cap 22 and the second end cap 31 forms the manifold 116.

[0058] Meanwhile, the raw water inlet position and wastewater outlet position in Example 2 are opposite to those in Example 1, that is, the water path direction is opposite, which causes the position of each water chamber to change.

[0059] Specifically, the raw water inlet 101 is located on the end face of the filter element housing 100, and the wastewater inlet 102 is located on the outer periphery of the filter element housing 100. The annular gap between the outer periphery of the second RO membrane element 2 and the inner periphery of the filter element housing 100 forms the second wastewater chamber 113, and the wastewater inlet 102 communicates with the second wastewater chamber 113. The raw water chamber 110 is formed by the first sealing structure 5, the end face of the third end cap 22, and the inner end face of one side of the filter element housing 100. The raw water inlet 101 communicates with the raw water chamber 110. The first sealing structure 5 separates the second wastewater chamber 113 and the raw water chamber 110. The second water pipe 32, which is eccentrically positioned on the second end cap 31, passes through the third end cap 22 and communicates with the raw water chamber 110. The first purified water chamber 112 and the second purified water chamber 115 are connected through the manifold 116, and the manifold 116 is connected to the purified water inlet 103 through the third water pipe 23 at the axis of the third end cap 22.

[0060] The axial gap between the first mounting end cap 117 and the end face of the first RO membrane element 1 and the end face of the second RO membrane element 2 is set as the first wastewater chamber 111. The retaining ring 118 of the first mounting end cap 117 separates the first wastewater chamber 111 and the second wastewater chamber 113.

[0061] The second sealing structure 6 separates the first wastewater chamber 111 and the first clean water chamber 112.

[0062] Example 3

[0063] The difference between Example 3 and Example 1 is that, as Figure 7 , Figure 8As shown, the raw water inlet 101 and the wastewater inlet 102 are both located at the same end of the filter element housing 100, wherein the wastewater inlet 102 is located at the axis of the filter element housing 100, and the clean water inlet 103 is located on the outer periphery of the other end of the filter element housing 100; a second mounting end cap 119 is installed at one end of the first central tube 11, and the axial gap between the second mounting end cap 119 and the inner end face of the filter element housing 100 is connected to the raw water cavity 110, so that the raw water inlet 101 is connected to the raw water cavity 110.

[0064] The first end cap 12 is located between the second mounting end cap 119 and the second end cap 31. The axial gap between the first end cap 12 and the second end cap 31 is the manifold 116. The axial gap between the first end cap 12 and the second mounting end cap 119 is the second wastewater chamber 113. The second water pipe 32 of the second end cap 31 passes through the first end cap 12 and the manifold 116 and communicates with the second wastewater chamber 113. The second mounting end cap 119 has a fourth water pipe 120 at its axial center. The second wastewater chamber 113 is connected to the wastewater outlet 102 through the fourth water pipe 120 of the second mounting end cap 119.

[0065] The axial gap between the first mounting end cap 117 and the inner end face of the filter element housing 100 forms the third purified water chamber 121. The first sealing structure 5 is installed on the retaining ring 118. The first sealing structure 5 separates the raw water chamber 110 and the third purified water chamber 121. One end of the second central tube 21 passes through the first mounting end cap 117 and is located in the third purified water chamber 121. The end of the second central tube 21 is provided with a drain hole 122. The second central tube 21 communicates with the third purified water chamber 121 through the drain hole 122. The purified water outlet 103 communicates with the third purified water chamber 121.

[0066] The above technical solution makes the overall structure more streamlined and the water flow smoother. The specific water path is as follows: the first water path is in the following order along the flow direction: raw water inlet 101, raw water chamber 110, first RO membrane element 1, first purified water chamber 112, manifold 116, second purified water chamber 115, third purified water chamber 121, and purified water inlet 103.

[0067] The second water channel consists of, in sequence along the flow direction, raw water inlet 101, raw water chamber 110, first RO membrane element 1, first wastewater chamber 111, second RO membrane element 2, second purified water chamber 115, third purified water chamber 121, and purified water inlet 103.

[0068] The third waterway, along the flow direction, consists of raw water inlet 101, raw water chamber 110, first RO membrane element 1, first wastewater chamber 111, second RO membrane element 2, second water pipe 32, second wastewater chamber 113, fourth water pipe 120, and wastewater inlet 102.

[0069] In other embodiments, based on the technical solution of embodiment 3, the positions of the first RO membrane element 1 and the second RO membrane element 2 can be swapped, and the raw water outlet 101 and the wastewater outlet 102 can be swapped. The specific location of the water chamber is not described here. The ultimate goal is to make the raw water flow in reverse, thus achieving the filtration path of the three water paths.

[0070] Example 4

[0071] The difference between Example 4 and Example 1 is that, as Figure 9 , Figure 10 As shown, the high recovery rate filter cartridge device also includes a movable ring plate 71, a fixed ring plate 72, a telescopic tube 73, a motor 74, a spring 75, a fixed sleeve 76, and a movable sleeve 77. The fixed sleeve 76 is sleeved and fixed on the outer periphery of the first RO membrane element 1, and the fixed sleeve 76 is densely covered with first water holes 78. The movable sleeve 77 is axially slidably sleeved on the outer periphery of the fixed sleeve 76, and the movable sleeve 77 is densely covered with second water holes 79.

[0072] The outer peripheral wall of the movable ring plate 71 is axially slidably disposed with the inner peripheral wall of the filter element housing 100. A transfer cavity 123 is formed between the movable ring plate 71 and the first sealing structure 5. The movable ring plate 71 separates the original water cavity 110 and the transfer cavity 123. One end of the movable sleeve 77 is fixed to the movable ring plate 71. The third water hole 80 is provided at this end of the movable sleeve 77. The elastic force of the spring 75 is used to force the movable ring plate 71 to move away from the first sealing structure 5.

[0073] The outer peripheral wall of the fixed ring plate 72 is coaxially fixed with the inner wall of the filter element housing 100. The fixed ring plate 72 is located on the side of the movable ring plate 71 away from the first sealing structure 5. The telescopic tube 73 is coaxially arranged with the filter element housing 100. The two ends of the telescopic tube 73 are fixed with the movable ring plate 71 and the fixed ring plate 72 respectively. The fixed ring plate 72, the movable ring plate 71, the inner wall of the filter element housing 100 and the outer wall of the telescopic tube 73 together form a pressure chamber 124. In order to ensure sealing, a sealing sleeve (not shown in the figure) is provided at the telescopic position of the telescopic tube 73.

[0074] The fixed ring plate 72 is provided with a first one-way valve 82, the movable ring plate 71 is provided with a second one-way valve 83, the motor 74 is installed on the outside of the filter element housing 100, the output shaft of the motor 74 passes through the filter element housing 100 and enters the pressurization chamber 124, and a cam 81 is fixed at the end of the output shaft of the motor 74. The cam 81 always abuts against the side of the movable ring plate 71. The motor 74 is used to maintain the position of the cam 81 or drive the cam 81 to rotate continuously.

[0075] When the motor 74 rotates to the state where the distance between the moving ring plate 71 and the fixed ring plate 72 is the shortest, the volume of the pressurization chamber 124 is at its minimum, and the first water hole 78 and the second water hole 79 overlap and connect (see...). Figure 10The inner diameter of the movable ring plate 71 abuts against the end face of the fixed sleeve 76 to separate the raw water chamber 110 and the transfer chamber 123. At this time, the raw water can only enter the first RO membrane element 1 from the outer periphery through the first water hole 78 and the second water hole 79 in sequence. At this time, the water resistance is small and the filtration effect is average, which is suitable for water quality with high conductivity.

[0076] When the motor 74 rotates to the state where the distance between the moving ring plate 71 and the fixed ring plate 72 is at its longest (see...) Figure 11 At this time, the volume of the pressurization chamber 124 is at its maximum. The first water hole 78 and the second water hole 79 are misaligned to seal the outer periphery of the first RO membrane element 1. The raw water chamber 110 is connected to the transfer chamber 123 and the end face of the first RO membrane element 1 through the third water hole 80. At this time, the raw water can enter the end face of the first RO membrane element 1 through the third water hole 80 and the transfer chamber 123 in sequence. At this time, the water resistance is relatively large, but the filtration effect is better, which is suitable for water quality with low conductivity.

[0077] The state adjustment of motor 74 has the following three application scenarios. First, when the conductivity of water is low, motor 74 can be used to maintain cam 81 in the state where the distance between moving ring plate 71 and fixed ring plate 72 is the longest.

[0078] The second method is to use a motor 74 to keep the cam 81 in the position where the distance between the moving ring plate 71 and the fixed ring plate 72 is at its maximum when the water has a high conductivity.

[0079] The third method is suitable for scenarios requiring a longer service life. Specifically, the motor 74 rotates continuously at a slow speed, causing the pressurization chamber 124 to continuously contract and expand, and to continuously switch between the raw water entering from the outer periphery or the end face. In this way, when the raw water enters from the outer periphery of the first RO membrane element 1, the raw water will initially move in a spiral inward along the inlet grid of the first RO membrane element 1 for a certain distance before moving axially and flowing out of the inlet grid. The overall path is shorter and the water resistance is smaller. However, when the raw water enters from the end face of the first RO membrane element 1, the raw water mainly moves axially. The raw water needs to travel the entire axial length of the first RO membrane element 1 to leave the inlet grid, that is, the overall path is shorter and the water resistance is larger. In addition, the direction of raw water movement is significantly different from the previous method. Therefore, when the raw water entry method is continuously switched, the direction of raw water movement changes continuously, and the direction of raw water scouring crystals on the first RO membrane element 1 also changes continuously. That is, by using a multi-angle scouring method, crystals can be removed quickly and without dead angles, thereby ensuring stable flux and extending service life.

[0080] Furthermore, since the first one-way valve 82 only allows raw water to enter the pressurization chamber 124, and the second one-way valve 83 only allows raw water to exit the pressurization chamber 124, as the pressurization chamber 124 continuously contracts and expands, the raw water in the pressurization chamber 124 will be intermittently pressurized and discharged into the transfer chamber 123 and enter from the end face of the first RO membrane element 1. That is, when the pressurization chamber 124 contracts, the pressurized water will accelerate its axial entry into the first RO membrane element 1. This can overcome water resistance and ensure filtration effect, accelerate the flushing of crystals, and allow the pressurized raw water and the atmospheric water entering from the outer periphery to merge in the first RO membrane element 1. The spirally moving atmospheric water will change the axial movement direction of the pressurized raw water to a certain extent, causing the pressurized raw water to be circumferentially deflected. The movement path of the pressurized raw water in the inlet grid of the first RO membrane element 1 is extended, the flushing range of crystals is increased, further ensuring stable flux and extending service life, and also extending the filtration contact time, thereby improving the filtration effect.

[0081] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A filter cartridge device with high recovery rate, characterized in that: The filter includes a filter housing (100), a first RO membrane element (1), a second RO membrane element (2), an inner membrane housing (3), a first central tube (11), a second central tube (21), a first sealing structure (5), a second sealing structure (6), a first mounting end cap (117), a movable ring plate (71), a fixed ring plate (72), a telescopic tube (73), a motor (74), a spring (75), a fixed sleeve (76), and a movable sleeve (77). The first RO membrane element (1) and the second RO membrane element (2) are nested together, and the flux of the first RO membrane element (1) is greater than that of the second RO membrane element (2). The filter housing (100) has a raw water inlet (101), a clean water inlet (103), and a wastewater inlet (102). The filter cartridge housing (100) comprises a raw water chamber (110), a first wastewater chamber (111), a first purified water chamber (112), a second wastewater chamber (113), and a second purified water chamber (115); the filter cartridge housing (100) has a first water path, a second water path, and a third water path. The first water path includes, in sequence along the flow direction, the raw water inlet (101), the raw water chamber (110), the first RO membrane element (1), the first purified water chamber (112), and the purified water inlet (103); the second water path includes, in sequence along the flow direction, the raw water inlet (101), the raw water chamber (110), the first RO membrane element (1), the first wastewater chamber (111), the second RO membrane element (2), the second purified water chamber (115), and the purified water inlet (116). The third water path includes, in sequence along the flow direction, the raw water inlet (101), the raw water chamber (110), the first RO membrane element (1), the first wastewater chamber (111), the second RO membrane element (2), the second wastewater chamber (113), and the wastewater inlet (102); both the first central tube (11) and the second central tube (21) have through holes (10), the first RO membrane element (1) is wound around the first central tube (11), the annular gap between the outer peripheral surface of the first RO membrane element (1) and the inner peripheral surface of the filter housing (100) is the raw water chamber (110), one end of the first central tube (11) is provided with a first end cap (12), and the first sealing structure The second wastewater chamber (113) is formed by the combination of the end face of the first end cap (12) and the inner end face of one side of the filter element housing (100). The first sealing structure (5) separates the second wastewater chamber (113) and the raw water chamber (110). The second RO membrane element (2) is wound around the second central tube (21). The inner membrane shell (3) is sleeved on the outer periphery of the second RO membrane element (2). The first central tube (11) is sleeved on the outer periphery of the inner membrane shell (3). An annular first purified water chamber (112) is formed between the inner periphery of the first central tube (11) and the outer periphery of the inner membrane shell (3). The inner cavity of the second central tube (21) is the second purified water chamber (115).The fixed sleeve (76) is fitted and fixed on the outer periphery of the first RO membrane element (1). The fixed sleeve (76) is densely covered with first water holes (78). The movable sleeve (77) is axially slidably fitted on the outer periphery of the fixed sleeve (76). The movable sleeve (77) is densely covered with second water holes (79). The movable ring plate (71) is axially slidably disposed with the inner wall of the filter element housing (100). The movable ring plate (71) and the first sealing structure (5) form a transfer cavity (123). The movable ring plate (71) separates the original water cavity (110) and the transfer cavity (123). The movable sleeve (76) is axially slidably fitted on the outer periphery of the first RO membrane element (1). One end of the movable ring plate (71) is fixed to the movable ring plate (72). The movable sleeve (77) has a third water hole (80) at this end. The elastic force of the spring (75) is used to force the movable ring plate (71) to move away from the first sealing structure (5). The outer peripheral wall of the fixed ring plate (72) is coaxially fixed to the inner wall of the filter element housing (100). The two ends of the telescopic tube (73) are respectively fixed to the movable ring plate (71) and the fixed ring plate (72). The fixed ring plate (72), the movable ring plate (71), the inner wall of the filter element housing (100) and the outer wall of the telescopic tube (73) together form a pressurizing chamber (124). The fixed ring plate (75) is fixed to the movable ring plate (71) and the fixed ring plate (72). 2) A first check valve (82) is provided, and a second check valve (83) is provided on the moving ring plate (71). The output shaft of the motor (74) is provided with a cam (81). The cam (81) abuts against the side of the moving ring plate (71). The motor (74) is used to maintain the position of the cam (81) or drive the cam (81) to rotate continuously. When the cam (81) rotates to the state where the distance between the moving ring plate (71) and the fixed ring plate (72) is the shortest, the first water hole (78) and the second water hole (79) overlap and communicate, and the inner diameter of the moving ring plate (71) abuts against the end face of the fixed sleeve (76). The moving ring plate (71) separates the raw water chamber (110) and the transfer chamber (123). Raw water enters the first RO membrane element (1) from the outer periphery through the first water hole (78) and the second water hole (79). When the cam (81) rotates to the state where the distance between the moving ring plate (71) and the fixed ring plate (72) is at its longest, the first water hole (78) and the second water hole (79) are misaligned to close the outer periphery of the first RO membrane element (1). The raw water chamber (110) then connects to the transfer chamber (123) and the end face of the first RO membrane element (1) through the third water hole (80).

2. The high recovery rate filter cartridge device according to claim 1, characterized in that: The desalination rate of the second RO membrane element (2) is greater than or equal to the desalination rate of the first RO membrane element (1).

3. The high recovery rate filter cartridge device according to claim 1, characterized in that: The water inlet method of the first RO membrane element (1) is peripheral water inlet and / or end face water inlet.

4. The high recovery rate filter cartridge device according to claim 1, characterized in that: One end of the inner membrane shell (3) is provided with a second end cap (31). The axial gap between the first end cap (12) and the second end cap (31) forms a manifold (116). The first purified water chamber (112) and the second purified water chamber (115) are connected through the manifold (116). The first end cap (12) has a first water pipe (13). The manifold (116) is connected to the purified water outlet (103) through the first water pipe (13). The first mounting end cap (117) is installed on the end of the second central tube (21) away from the second end cap (31). The axial gap between the first mounting end cap (117) and the end face of the first RO membrane element (1) and the end face of the second RO membrane element (2) is set as the first wastewater chamber (111). An retaining ring (118) is provided on the outer edge of the end cap (117). The retaining ring (118) overlaps the outer periphery of the first RO membrane element (1). The retaining ring (118) separates the raw water chamber (110) and the first wastewater chamber (111). The second sealing structure (6) is disposed in the gap between the first central tube (11) and the inner membrane shell (3) at the end away from the second end cap (31). The second sealing structure (6) separates the first wastewater chamber (111) and the first clean water chamber (112). The wastewater outlet (102) communicates with the second wastewater chamber (113). The second end cap (31) has a second water pipe (32). The second water pipe (32) passes through the manifold (116) and the first end cap (12) and communicates with the second wastewater chamber (113).

Images