A natural drinking water treatment system and treatment process thereof

Abstract

The invention discloses a natural drinking water treatment system and a treatment process thereof. The drinking water treatment system comprises a coarse filter for coarse filtration of water, a fine filter for fine filtration of water, an ultrafiltration membrane filter for ultrafiltration of water, a disinfection box for ultraviolet disinfection of filtered water, a backwashing water storage tank for backwashing the ultrafiltration membrane filter and a water storage tank for storing backwash water. An outer flow limiting sleeve, an inner flow limiting sleeve and a filter membrane cylinder arranged from outside to inside and coaxially arranged are arranged inside the ultrafiltration membrane filter. The natural drinking water treatment system of the invention can perform coarse filtration, fine filtration and ultrafiltration membrane filtration on water in sequence, and disinfect the pure water after membrane filtration in batches. The system is practical in function. During membrane filtration, impurities on the outside of the filter membrane cylinder are washed by cross-flow to ensure the filtration efficiency of the membrane. The filter membrane can also be backwashed and the surface of the membrane can be washed with bubbles.

Description

Technical Field

[0001] The invention relates to the technical field of drinking water processing, and in particular to a natural drinking water treatment system and a treatment process thereof. Background Art

[0002] Drinking water refers to water that can be drunk directly. Drinking water should meet certain hygiene standards to ensure human health and life safety. After taking water from groundwater sources, it needs to undergo a series of treatments such as removal of impurities, filtration and disinfection before it can become drinking water.

[0003] In the process of drinking water treatment, water is usually filtered by membrane filtration to obtain pure water. When water is filtered by ultrafiltration membrane, cross-flow filtration is a common filtration method. During the membrane cross-flow filtration process, impurities will accumulate on the water inlet side of the membrane, affecting the filtration efficiency of the membrane. The membrane needs to be cleaned regularly to maintain the stable filtration capacity of the membrane. In the prior art, the cleaning of the filter membrane is generally done by connecting the pipeline separately for cleaning after the water filtration is completed, which affects the water treatment efficiency. Summary of the invention

[0004] The present invention solves the problem of inconvenient cleaning of the filter membrane in the drinking water treatment system in the prior art and proposes a natural drinking water treatment system and a treatment process thereof. A backwash function is set in the drinking water treatment system. The water treatment system can directly backwash the filter membrane regularly to ensure the membrane filtration efficiency during the water treatment process.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A natural drinking water treatment system comprises a coarse filter for coarse filtration of water, a fine filter for fine filtration of water, an ultrafiltration membrane filter for ultrafiltration of water, a disinfection box for ultraviolet disinfection of filtered water and a backwashing water storage tank for backwashing of the ultrafiltration membrane filter, which are connected in sequence.

[0007] The ultrafiltration membrane filter is in an inverted cone shape, the water inlet pipe of the ultrafiltration membrane filter is tangent to the conical surface of the ultrafiltration membrane filter, and a debris removal pipe is arranged at the bottom of the ultrafiltration membrane filter. The outer flow limiting sleeve, the inner flow limiting sleeve and the filter membrane cylinder are coaxially arranged from the outside to the inside at the middle of the top of the ultrafiltration membrane filter, and the upper connecting seat at the upper end of the filter membrane cylinder is provided with a water outlet pipe, and the water outlet pipe is respectively connected to the backwash water storage tank and the disinfection tank, and a central water inlet valve is arranged between the lower connecting seat at the lower end of the filter membrane cylinder and the outer flow limiting sleeve, and the inside of the outer flow limiting sleeve is connected to the water inlet pipe through a drain pipe.

[0008] The outer flow limiting sleeve and the inner flow limiting sleeve are connected in an axial sliding manner, and the outer flow limiting sleeve is provided with an outer liquid flow hole, and the inner flow limiting sleeve is provided with an inner liquid flow hole. When the outer liquid flow hole is connected with the inner liquid flow hole, the central water inlet valve is closed, and the water inside the ultrafiltration membrane filter enters the inner flow limiting sleeve through the outer liquid flow hole and the inner liquid flow hole; when the outer liquid flow hole is not connected with the inner liquid flow hole, the central water inlet valve is opened, and the water inside the ultrafiltration membrane filter enters the inner flow limiting sleeve from the bottom of the inner flow limiting sleeve.

[0009] Preferably, the central water inlet valve comprises a movable blocking ring, an elastic member, a fixed sleeve and a fixed blocking ring, the fixed sleeve is fixedly sleeved on the lower connecting seat, the movable blocking ring is axially movable sleeved on the lower connecting seat, and the movable blocking ring is connected to the fixed sleeve via an elastic member. The fixed blocking ring is coaxially fixedly connected to the interior of the inner flow limiting sleeve, the fixed blocking ring and the movable blocking ring are attached to form a closed state of the central water inlet valve, and the fixed blocking ring and the movable blocking ring are separated to form an open state of the central water inlet valve.

[0010] Preferably, an isolation cover plate and an upper connecting seat are arranged on the top of the outer current limiting sleeve to form a seal on the upper part of the outer current limiting sleeve. An adjustment cylinder is arranged on the upper part of the isolation cover plate, a piston plate is arranged inside the adjustment cylinder, the lower part of the piston plate is connected to a connecting sleeve that passes through the isolation cover plate and is fixedly connected to the inner current limiting sleeve, the lower part of the piston plate is connected to a connecting rod that passes through the top plate of the adjustment cylinder, and the connecting rod is driven by the adjustment cylinder to move up and down.

[0011] Preferably, a liquid level detector is provided on the disinfection box, the liquid level detector is connected to the input end of the controller, and the output end of the controller is connected to the regulating cylinder. When one of the disinfection boxes reaches the target liquid level, the controller drives the regulating cylinder to perform a driving action, and the inner limiting sleeve moves axially relative to the outer limiting sleeve to form the outer liquid flow hole connected or disconnected with the inner liquid flow hole.

[0012] Preferably, an axially extending outer flow guide tube is provided on the inner wall of the outer flow limiting sleeve, the lower part of the outer flow guide tube extends between the inner flow limiting sleeve and the fixed blocking ring, and the outer air inlet at the upper part of the outer flow guide tube is opposite to the outer wall of the inner flow limiting sleeve. An axially extending inner flow guide tube is provided on the outer wall of the inner flow limiting sleeve, the upper part of the inner flow guide tube extends between the outer flow limiting sleeve and the connecting sleeve, and the inner air outlet at the lower part of the inner flow guide tube is opposite to the inner wall of the outer flow limiting sleeve. The inner flow limiting sleeve is rotatably connected to the outer flow limiting sleeve to form a connection or disconnection between the outer flow guide tube and the inner flow guide tube.

[0013] Preferably, an outer bubble net is provided at the outer air outlet at the lower part of the outer guide tube, and an inner bubble net is provided at the lower part of the inner flow limiting sleeve. When the outer guide tube is connected to the inner guide tube, the inner bubble net and the outer bubble net are positioned correspondingly.

[0014] The beneficial effects of the present invention are:

[0015] 1. This natural drinking water treatment system can sequentially perform coarse filtration, fine filtration and ultrafiltration membrane filtration on water, and disinfect the purified water after membrane filtration in batches. It is practical and can ensure the quality of water treatment while having high treatment efficiency. In addition, this natural drinking water treatment system can intermittently flow on the surface of the filter membrane cartridge through the intermittent connection between the external liquid flow holes and the internal liquid flow holes. The crossflow is used to flush impurities on the outside of the filter membrane cartridge, reduce the accumulation of impurities on the surface of the filter membrane cartridge, and ensure the filtration efficiency.

[0016] 2. This natural drinking water treatment system is equipped with a backwash water storage tank and a water storage tank, which can backwash and clean the filter membrane cartridge inside the ultrafiltration membrane filter to remove impurities accumulated on the surface of the filter membrane cartridge and form a backwash cycle. The water flow can assist in flushing the surface of the filter membrane cartridge, reduce the pressure difference between the inside and outside of the filter membrane cartridge, and avoid damage to the membrane caused by excessive pressure exerted by the water inside the filter membrane cartridge during backwashing. At the same time, it also reduces the influence of water pressure on the bonding strength between the membrane and the membrane support.

[0017] 3. The natural drinking water treatment system is also provided with an external guide pipe and an internal guide pipe which can be connected. During backwashing, air bubbles are introduced into the outside of the filter membrane cartridge. Combined with the backwash water circulation, the outside of the filter membrane cartridge can be flushed with bubbles to enhance the cleaning effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a structural diagram of the natural drinking water treatment system;

[0019] Figure 2 This is a structural schematic diagram of the ultrafiltration membrane filter of the natural drinking water treatment system;

[0020] Figure 3 This is a structural schematic diagram of the cross section of the outer flow limiting sleeve of Example 1 of the natural drinking water treatment system;

[0021] Figure 4 This is a schematic structural diagram of the cross section of the outer flow limiting sleeve of Example 2 of the natural drinking water treatment system;

[0022] Figure 5 This is a schematic structural diagram of the axial cross section when the outer flow guide pipe and the inner flow guide pipe of Example 2 of the natural drinking water treatment system are connected;

[0023] Figure 6 This is a structural diagram of the isolation cover of the natural drinking water treatment system;

[0024] Figure 7 This is a schematic diagram of the structure at the radial cross section when the outer guide pipe and the inner guide pipe are connected in Example 2 of the natural drinking water treatment system;

[0025] Figure 8This is a schematic structural diagram of a radial cross section of the outer bubble network of Example 2 of the natural drinking water treatment system.

[0026] In the figure: 1, coarse filter; 2, water storage tank; 3, fine filter; 4, ultrafiltration membrane filter; 5, backwash water storage tank; 6, disinfection tank; 7, external flow limiting sleeve; 8, internal flow limiting sleeve; 9, filter membrane cylinder; 10, water outlet pipe; 11, water outlet valve; 12, adjustment cylinder; 13, isolation cover; 14, adjustment cylinder; 15, drive wheel; 16, drive motor;

[0027] 21. Water storage inlet pipe; 22. Water storage outlet pipe; 41. Water inlet pipe; 42. De-impurity pipe; 43. Drain pipe; 421. De-impurity valve; 51. Water storage pipe; 52. Water storage valve; 53. Backwash pipe; 61. Disinfection liquid inlet valve; 62. Disinfection liquid outlet valve; 63. Liquid level detector;

[0028] 71, external liquid flow hole; 72, external flow guide tube; 721, external flow guide channel; 722, external air inlet; 723, external bubble net; 81, internal liquid flow hole; 82, internal flow guide tube; 83, connecting hose; 84, internal bubble net; 821, internal flow guide channel; 822, internal air outlet; 91, upper connecting seat; 92, lower connecting seat; 93, central water inlet valve; 931, movable blocking ring; 932, supporting elastic member; 933, fixed sleeve; 934, fixed blocking ring;

[0029] 121. Piston plate; 122. Connecting sleeve; 123. Buffer elastic member; 124. Connecting rod; 125. Follower wheel; 126. Air cavity; 127. One-way air inlet pipe; 128. First one-way air outlet pipe; 1221. Lower connecting hole; 1222. Upper connecting hole; 131. Movable ring; 132. Second one-way air outlet pipe; 141. Connecting bracket; 161. Telescopic driving rod; 162. Synchronous bracket. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0031] Reference Figure 1 A natural drinking water treatment system includes a coarse filter 1 for coarse filtration of water, a fine filter 3 for fine filtration of water, an ultrafiltration membrane filter 4 for ultrafiltration of water, a disinfection box 6 for ultraviolet disinfection of filtered water, and a backwashing water storage tank 5 for backwashing the ultrafiltration membrane filter 4.

[0032] The water outlet of the coarse filter 1 is connected to the water inlet of the fine filter 3, and the water outlet of the fine filter 3 is connected to the water inlet pipe 41 of the ultrafiltration membrane filter 4. The water outlet pipe 10 of the ultrafiltration membrane filter 4 is respectively connected to the backwash water storage tank 5 and multiple disinfection boxes 6. Among them, the backwash water storage tank 5 is respectively connected to the water outlet pipe 10 through the water storage pipe 51 and the backwash pipe 53. The water storage pipe 51 is provided with a water storage valve 52, and the backwash pipe 53 is provided with a backwash pump and a backwash valve. The water of the water outlet pipe 10 enters the backwash water storage tank 5 through the water storage pipe 51 for storage. When the membrane inside the ultrafiltration membrane filter 4 needs to be backwashed, the water inside the backwash water storage tank 5 enters the ultrafiltration membrane filter 4 again from the backwash pipe 53 and the water outlet pipe 10.

[0033] Furthermore, a water outlet valve 11 is provided on the pipeline of the water outlet pipe 10 connected to the disinfection box 6. There are multiple disinfection boxes 6, and a disinfection liquid inlet valve 61 is provided at the water inlet end of each disinfection box 6, and a disinfection liquid outlet valve 62 is provided at the water outlet end of the disinfection box 6. A liquid level detector 63 for detecting the liquid level of the water body inside the disinfection box 6 is provided on the disinfection box 6. After the water in the water outlet pipe 10 fills one disinfection box 6, it enters another disinfection box 6 to perform batch disinfection on the water. The liquid level detector 63 detects the liquid level of the water inside the disinfection box 6 and is used to detect the water volume inside the disinfection box 6.

[0034] refer to Figure 2 The ultrafiltration membrane filter 4 is in an inverted cone shape, the water inlet pipe 41 of the ultrafiltration membrane filter 4 is tangent to the conical surface of the ultrafiltration membrane filter 4, and the impurity removal pipe 42 is arranged at the bottom of the ultrafiltration membrane filter 4. A coaxial outer flow limiting sleeve 7, an inner flow limiting sleeve 8 and a filter membrane cylinder 9 are arranged in the middle of the top of the ultrafiltration membrane filter 4. The outer flow limiting sleeve 7, the inner flow limiting sleeve 8 and the filter membrane cylinder 9 are arranged from the outside to the inside. The outer flow limiting sleeve 7 and the inner flow limiting sleeve 8 are attached to each other, and a membrane filtration space is formed between the inner flow limiting sleeve 8 and the filter membrane cylinder 9. An isolation cover plate 13 is arranged on the top of the outer flow limiting sleeve 7, and an upper connecting seat 91 is arranged on the upper end of the filter membrane cylinder 9. The isolation cover plate 13 is fixedly connected to the upper connecting seat 91, and the isolation cover plate 13 and the upper connecting seat 91 in the middle form a seal on the upper part of the outer flow limiting sleeve 7. An outlet pipe 10 is provided at the upper connecting seat 91 at the upper end of the filter membrane cylinder 9 , and the outlet pipe 10 is respectively connected to the backwash water storage tank 5 and the disinfection tank 6 , and the interior of the external flow limiting sleeve 7 is connected to the water inlet pipe 41 through the drain pipe 43 .

[0035] The water after fine filtration enters the ultrafiltration membrane filter 4 from the water inlet pipe 41, generates a vortex inside the ultrafiltration membrane filter 4, and performs impurity removal and separation again. The water with impurities is discharged from the impurity removal pipe 42 at the bottom of the ultrafiltration membrane filter 4, and the impurity-free water enters the membrane filtration space from the bottom of the outer flow limiting sleeve 7 and the inner flow limiting sleeve 8. The filter membrane cylinder 9 is a cylinder with a filter membrane set on the side of the cylinder. A part of the water is filtered through the filter membrane cylinder 9, and the pure water is discharged through the water outlet pipe 10. The unfiltered water enters the interior of the ultrafiltration membrane filter 4 again from the drain pipe 43 and the water inlet pipe 41 for circulation filtration. The drain pipe 43 is a one-way pipe.

[0036] Furthermore, a lower connecting seat 92 is provided at the lower end of the filter membrane cartridge 9, and the lower connecting seat 92 is fixedly connected to the outer flow limiting sleeve 7 through a bracket. A central water inlet valve 93 is provided between the lower connecting seat 92 and the outer flow limiting sleeve 7, and the central water inlet valve 93 is located below the inner flow limiting sleeve 8.

[0037] refer to Figure 2 The central water inlet valve 93 includes a movable blocking ring 931, a supporting elastic member 932, a fixed sleeve 933 and a fixed blocking ring 934. The fixed sleeve 933 is fixedly sleeved on the lower connecting seat 92, and the movable blocking ring 931 is axially movable sleeved on the lower connecting seat 92. The movable blocking ring 931 and the fixed sleeve 933 are connected through the supporting elastic member 932. The fixed blocking ring 934 is coaxially fixedly connected to the inside of the inner flow limiting sleeve 8. The fixed blocking ring 934 and the movable blocking ring 931 are attached to form the closed state of the central water inlet valve 93, and the fixed blocking ring 934 and the movable blocking ring 931 are separated to form the open state of the central water inlet valve 93.

[0038] The upper part of the isolation cover plate 13 is provided with an adjustment cylinder 12, and a piston plate 121 is provided inside the adjustment cylinder 12. The lower part of the piston plate 121 is connected to a connecting sleeve 122 that penetrates the isolation cover plate 13 and is fixedly connected to the inner flow limiting sleeve 8. A buffer elastic member 123 is provided between the piston plate 121 and the upper connecting seat 91. The connecting sleeve 122 is provided with a lower connecting hole 1221, and the lower connecting hole 1221 is used to connect the inner part of the inner flow limiting sleeve 8 with the inner part of the outer flow limiting sleeve 7. The water inside the inner flow limiting sleeve 8 can be discharged from the drain pipe 43 through the lower connecting hole 1221. The lower part of the piston plate 121 is connected to a connecting rod 124 that penetrates the top plate of the adjustment cylinder 12. The connecting rod 124 is connected to the adjustment cylinder 14. The adjustment cylinder 14 is used to drive the driving connecting rod 124, so that the piston plate 121, the connecting sleeve 122 and the inner flow limiting sleeve 8 move up and down, and the outer flow limiting sleeve 7 and the inner flow limiting sleeve 8 The axial sliding relationship is formed.

[0039] refer to Figure 2 and Figure 3The outer flow hole 71 is provided on the outer flow limiting sleeve 7, and the inner flow hole 81 is provided on the inner flow limiting sleeve 8. The outer flow hole 71 and the inner flow hole 81 can be connected or disconnected by axially moving the inner flow limiting sleeve 8 relative to the outer flow limiting sleeve 7.

[0040] During membrane filtration, when the outer liquid flow hole 71 is not connected to the inner liquid flow hole 81, there is a hydraulic pressure difference between the inside of the ultrafiltration membrane filter 4 and the membrane filtration space, and the water inside the ultrafiltration membrane filter 4 flushes the movable blocking ring 931 away from the fixed blocking ring 934. The central water inlet valve 93 is opened, and the water inside the ultrafiltration membrane filter 4 enters the inner flow limiting sleeve 8 from the bottom of the inner flow limiting sleeve 8. The water flow in the membrane filtration space flows vertically upward to form a circulating filtration. When the outer liquid flow hole 71 is connected to the inner liquid flow hole 81, the water inside the ultrafiltration membrane filter 4 directly enters the membrane filtration space through the outer liquid flow hole 71 and the inner liquid flow hole 81. The central water inlet valve 93 is closed, and the membrane filtration space forms a crossflow, which is used to flush the impurities outside the filter membrane cylinder 9, reduce the accumulation of impurities on the surface of the filter membrane cylinder 9, and ensure the filtration efficiency.

[0041] Furthermore, the liquid level detector 63 of the disinfection box 6 is connected to the input end of the controller, and the output end of the controller is connected to the regulating cylinder 14. When one of the disinfection boxes 6 reaches the target liquid level, the controller drives the regulating cylinder 14 to perform a driving action. The controller controls the regulating cylinder 14 to work, and the regulating cylinder 14 pushes the inner limiting sleeve 8 to move axially relative to the outer limiting sleeve 7, so that the outer liquid flow hole 71 and the inner liquid flow hole 81 change from a disconnected state to a connected state, forming a cross-flow in the membrane filtration space, and cleaning the impurities on the surface of the filter membrane tube 9. After a certain period of cleaning, the regulating cylinder 14 pushes the inner limiting sleeve 8 to move axially relative to the outer limiting sleeve 7, so that the outer liquid flow hole 71 and the inner liquid flow hole 81 change from a connected state to a disconnected state, and the membrane filtration proceeds normally.

[0042] After the pure water of the natural drinking water treatment system comes out from the water outlet pipe 10, the pure water entering the disinfection box 6 is directly processed into finished water, and the pure water entering the backwash water storage tank 5 is used to backwash the ultrafiltration membrane filter 4. When the backwash water storage tank 5 is full of water, the outlet valve 11 and the outlet end of the fine filter 3 are closed and adjusted to a non-connected state, the backwash valve is opened, and the backwash pump introduces the pure water inside the backwash water storage tank 5 into the interior of the filter membrane cartridge 9 through the outlet pipe 10 to backwash the filter membrane cartridge 9. At this time, the central water inlet valve 93 is closed, and the central backwash water enters the ultrafiltration membrane filter 4 again from the drain pipe 43 and the water inlet pipe 41 in the inner limiting sleeve 8. After the ultrafiltration membrane filter 4 is full of water, the outer liquid flow hole 71 and the inner liquid flow hole 81 are adjusted to a connected state, and the water of the ultrafiltration membrane filter 4 enters the membrane filtration space from the outer liquid flow hole 71 and the inner liquid flow hole 81 to assist in flushing the surface of the filter membrane cartridge 9. At the same time, a counter-hydraulic pressure is formed in the membrane filtration space outside the filter membrane cartridge 9, so that the pressure difference between the inside and outside of the filter membrane cartridge 9 is reduced, so as to avoid excessive pressure on the membrane by the water inside the filter membrane cartridge 9 during backwashing, causing damage to the membrane, and also reducing the influence on the bonding strength between the membrane and the membrane support.

[0043] refer to Figure 1 The natural drinking water treatment system further includes a water storage tank 2, which is used to store backwash water. The water storage tank 2 is connected to the water inlet pipe 41 through a water storage inlet pipe 21 and a water storage outlet pipe 22. The water storage inlet pipe 21 is a one-way pipe for water to flow into the water storage tank 2, and the water storage outlet pipe 22 is a one-way pipe for water to flow out of the water storage tank 2. A water outlet pump is provided on the water storage outlet pipe 22.

[0044] A debris removal valve 421 is provided on the debris removal pipe 42. During membrane filtration, the debris removal valve 421 on the debris removal pipe 42 is opened, and impurities are discharged from the debris removal pipe 42. During membrane backwashing, the debris removal valve 421 on the debris removal pipe 42 is closed. After the ultrafiltration membrane filter 4 is full of water, the backwash water enters the water storage tank 2 from the drain pipe 43 and the water storage inlet pipe 21, and then enters the ultrafiltration membrane filter 4 from the water storage outlet pipe 22 and the water inlet pipe 41. The flow rate of the water storage inlet pipe 21 is greater than the flow rate of the water storage outlet pipe 22, so that the backwash water is kept circulating inside the ultrafiltration membrane filter 4, and the excess backwash water can enter the water storage tank 2 for storage. After backwashing is completed, the water inside the water storage tank 2 comes out from the water storage outlet pipe 22 and is filtered again.

[0045] In this embodiment, the natural drinking water treatment system includes the following water treatment steps:

[0046] Step A1: water enters the coarse filter 1 from the water inlet end of the coarse filter 1, is coarsely filtered, and is discharged from the water outlet end of the coarse filter 1;

[0047] Step A2: the water after the coarse filtration enters the fine filter 3 from the water inlet end of the fine filter 3, and is discharged from the water outlet end of the fine filter 3 after being finely filtered;

[0048] Step A3: The water after fine filtration enters the ultrafiltration membrane filter 4 from the water inlet pipe 41, and a vortex is generated inside the ultrafiltration membrane filter 4 to remove impurities and separate again. The water with impurities is discharged from the impurity removal pipe 42 at the bottom of the ultrafiltration membrane filter 4. At this time, the outer liquid flow hole 71 is not connected with the inner liquid flow hole 81, and the central water inlet valve 93 is opened. The water after impurity removal enters the membrane filtration space from the bottom of the outer flow limiting sleeve 7 and the inner flow limiting sleeve 8. A part of the water is filtered through the filter membrane cylinder 9 to obtain pure water and is discharged through the water outlet pipe 10. The unfiltered water enters the interior of the ultrafiltration membrane filter 4 again from the drain pipe 43 and the water inlet pipe 41 for circulation filtration;

[0049] Step A4: The water in the outlet pipe 10 enters the backwash water storage tank 5 and the disinfection tank 6 respectively at a certain flow rate. When a disinfection tank 6 reaches the target liquid level, the controller drives the regulating cylinder 14 to work, and the regulating cylinder 14 pushes the inner limiting sleeve 8 to move axially relative to the outer limiting sleeve 7, so that the outer liquid flow hole 71 and the inner liquid flow hole 81 change from a disconnected state to a connected state. The water inside the ultrafiltration membrane filter 4 directly enters the membrane filtration space through the outer liquid flow hole 71 and the inner liquid flow hole 81, and the central water inlet valve 93 is closed. A crossflow is formed in the membrane filtration space to flush impurities outside the filter membrane cylinder 9 to ensure the filtration efficiency of the filter membrane cylinder 9.

[0050] Step A5: After flushing for a certain period of time, the regulating cylinder 14 pushes the inner flow limiting sleeve 8 to move axially relative to the outer flow limiting sleeve 7, so that the outer liquid flow hole 71 and the inner liquid flow hole 81 change from a connected state to a disconnected state, and the membrane filtration proceeds normally;

[0051] Step A6: When the backwash water storage tank 5 is full of water, the outlet valve 11, the outlet end of the fine filter 3 and the impurity removal valve 421 are closed, the regulating cylinder 14 adjusts the external liquid flow hole 71 and the internal liquid flow hole 81 to a disconnected state, the backwash valve is opened, and the backwash pump introduces the pure water inside the backwash water storage tank 5 into the inside of the filter membrane cartridge 9 through the outlet pipe 10 to reversely flush the filter membrane cartridge 9. At this time, the central water inlet valve 93 is closed, and the central backwash water enters the ultrafiltration membrane filter 4 again through the inner limiting sleeve 8 from the drain pipe 43 and the water inlet pipe 41;

[0052] Step A7: After the interior of the ultrafiltration membrane filter 4 is full of water, the outer liquid flow hole 71 and the inner liquid flow hole 81 are adjusted to be in a connected state, and the water of the ultrafiltration membrane filter 4 enters the membrane filtration space from the outer liquid flow hole 71 and the inner liquid flow hole 81 to assist in flushing the surface of the filter membrane cartridge 9. At the same time, a counter-hydraulic pressure is formed in the membrane filtration space outside the filter membrane cartridge 9, so that the pressure difference between the inside and outside of the filter membrane cartridge 9 is reduced, so as to avoid excessive pressure on the membrane by the water inside the filter membrane cartridge 9 during backwashing, thereby causing damage to the membrane, and also reduce the influence on the bonding strength between the membrane and the membrane support body;

[0053] At the same time, the water storage inlet pipe 21 and the water storage outlet pipe 22 are changed from closed to open, and the backwash water enters the water storage tank 2 from the drain pipe 43 and the water storage inlet pipe 21, and then enters the ultrafiltration membrane filter 4 from the water storage outlet pipe 22 and the water inlet pipe 41, so that the backwash water is kept circulating inside the ultrafiltration membrane filter 4, and the excess backwash water can enter the water storage tank 2 for storage;

[0054] Step A8: After backwashing is completed, the backwash valve is closed, the outlet valve 11, the outlet end of the fine filter 3 and the impurity removal valve 421 are opened, the water storage inlet pipe 21 is closed, and the water storage outlet pipe 22 remains open. The natural drinking water treatment system continues to perform membrane filtration on the water after fine filtration. At the same time, the water inside the water storage tank 2 comes out of the water storage outlet pipe 22 and is membrane filtered again.

[0055] Example 2

[0056] The difference between this embodiment and embodiment 1 is that, based on embodiment 1, reference Figure 4 and Figure 5 In this embodiment, an axially extending outer flow guide tube 72 is provided on the inner wall of the outer flow limiting sleeve 7, and an outer air inlet 722 at the upper part of the outer flow guide tube 72 is opposite to the outer wall of the inner flow limiting sleeve 8, and an outer air outlet at the lower part of the outer flow guide tube 72 extends to between the inner flow limiting sleeve 8 and the fixed blocking ring 934, and an outer bubble net 723 is provided at the outer air outlet at the lower part of the outer flow guide tube 72.

[0057] Furthermore, an axially extending inner flow guide tube 82 is provided on the outer wall of the inner flow limiting sleeve 8 , the upper part of the inner flow guide tube 82 extends between the outer flow limiting sleeve 7 and the connecting sleeve 122 , and the inner air outlet 822 at the lower part of the inner flow guide tube 82 is opposite to the inner wall of the outer flow limiting sleeve 7 .

[0058] A rotating plate is provided in the middle of the piston plate 121 of the adjustment cylinder 12 and is rotatably sealed with the piston plate 121. The upper part of the rotating plate is fixedly connected to the connecting rod 124, and the lower part of the rotating plate is fixedly connected to the connecting sleeve 122. Figure 6 The isolation cover plate 13 is provided with a movable ring 131 rotatably connected to the isolation cover plate 13, the outer edge of the movable ring 131 is rotatably connected to the outer current limiting sleeve 7, and the connecting sleeve 122 runs through the movable ring 131. The rotating plate, the connecting sleeve 122, the connecting rod 124 and the movable ring 131 on the piston plate 121 can rotate relative to the outer current limiting sleeve 7, and the inner current limiting sleeve 8 connected to the lower part of the connecting sleeve 122 can rotate relative to the outer current limiting sleeve 7.

[0059] refer to Figure 2The top of the connecting rod 124 is fixedly connected to the follower wheel 125. The ultrafiltration membrane filter 4 is provided with a driving wheel 15 and a driving motor 16. The driving wheel 15 is fixedly connected to the output shaft of the driving motor 16. The driving wheel 15 is meshed with the follower wheel 125. The driving motor 16 can drive the follower wheel 125 to rotate through the driving wheel 15, so that the inner current limiting sleeve 8 rotates relative to the outer current limiting sleeve 7. Further, a retractable telescopic driving rod 161 is provided on the output shaft of the driving motor 16. The follower wheel 125 is fixedly sleeved on the shaft member at the telescopic end of the telescopic driving rod 161. The shaft member at the telescopic end of the telescopic driving rod 161 is rotatably connected to the synchronous bracket 162. The connecting rod 124 is also rotatably connected to the synchronous bracket 162. The synchronous bracket 162 is connected to the working end of the regulating cylinder 14 through the connecting bracket 141. When the connecting rod 124 moves up and down, the synchronous bracket 162 is used to keep the telescopic driving rod 161 extending and retracting following the movement of the connecting rod 124, thereby maintaining stable engagement between the driving wheel 15 and the follower wheel 125.

[0060] By the relative rotation of the inner limiting sleeve 8 and the outer limiting sleeve 7, Figure 7 The outer air inlet 722 at the upper portion of the outer guide tube 72 can be connected to the inner air outlet 822 at the lower portion of the inner guide tube 82, thereby forming a connection between the outer guide tube 72 and the inner guide tube 82. Figure 6 When the outer guide tube 72 is connected to the inner guide tube 82, the correspondence between the axial connection positions of the outer liquid flow hole 71 and the inner liquid flow hole 81 is not affected, and further, the connection between the outer liquid flow hole 71 and the inner liquid flow hole 81 during relative axial movement is not affected.

[0061] refer to Figure 5 and Figure 6 The air cavity 126 at the lower part of the piston plate 121 of the adjustment cylinder 12 is provided with a one-way air inlet pipe 127 and a first one-way air outlet pipe 128. When the piston plate 121 moves relative to the adjustment cylinder 12, the one-way air inlet pipe 127 is used for air intake of the air cavity 126, and the first one-way air outlet pipe 128 is used for air outlet of the air cavity 126. Further, the movable ring 131 is provided with a second one-way air outlet pipe 132, which is connected to the inner guide pipe 82 and the air cavity 126 through the connecting hose 83, and the second one-way air outlet pipe 132 can be used for air outlet of the air cavity 126. The connecting sleeve 122 is provided with an upper connecting hole 1222 above the isolation cover plate 13, which is used to keep the connecting sleeve 122 in the space between the isolation cover plate 13 and the piston plate 121 for gas flow.

[0062] When the outer flow guide tube 72 is not connected to the inner flow guide tube 82, the inner air outlet 822 of the inner flow guide tube 82 is in a closed state, and the first one-way air outlet 128 is used for the air outlet of the air cavity 126; when the outer flow guide tube 72 is connected to the inner flow guide tube 82, the inner air outlet 822 of the inner flow guide tube 82 is connected to the outer air inlet 722 at the upper part of the outer flow guide tube 72, and the second one-way air outlet 132 is used for the air outlet of the air cavity 126. The gas inside the air cavity 126 is discharged from the second one-way air outlet 132, and enters the interior of the inner flow limiting sleeve 8 through the connecting hose 83, the inner flow guide channel 821 inside the inner flow guide tube 82, the outer flow guide channel 721 inside the outer flow guide tube 72, and the outer bubble net 723. The outer bubble net 723 can divide the gas, form bubbles inside the inner flow limiting sleeve 8, and perform bubble flushing on the outside of the filter membrane cylinder 9 to enhance the cleaning effect.

[0063] For further reference, Figure 5 and Figure 8 The inner air bubble net 84 is disposed at the lower part of the inner flow limiting sleeve 8. When the outer flow guide tube 72 is connected to the inner flow guide tube 82, the inner air bubble net 84 and the outer air bubble net 723 are located in a corresponding position. The regulating cylinder 14 pushes the inner flow limiting sleeve 8 to move back and forth axially relative to the outer flow limiting sleeve 7. The outer flow guide tube 72 is continuously connected to the inner flow guide tube 82. The inner air bubble net 84 and the outer air bubble net 723 move back and forth relative to each other, which can strengthen the gas segmentation, form finer bubbles, and have better flushing ability.

[0064] The water treatment steps of the natural drinking water treatment system in this embodiment that are different from those in Embodiment 1 are as follows:

[0065] Step B1: During membrane filtration, refer to Figure 4 , the outer flow guide tube 72 is not connected to the inner flow guide tube 82;

[0066] Step B2: Before the membrane is backwashed, the driving motor 16 drives the follower wheel 125 to rotate through the driving wheel 15, so that the inner flow limiting sleeve 8 rotates relative to the outer flow limiting sleeve 7, and the outer air inlet 722 at the upper part of the outer flow guide tube 72 and the inner air outlet 822 at the lower part of the inner flow guide tube 82 can be connected, so that the outer flow guide tube 72 and the inner flow guide tube 82 are connected;

[0067] Step B3: When the membrane is backwashed, the regulating cylinder 14 pushes the inner limiting sleeve 8 to move axially back and forth in a small range relative to the outer limiting sleeve 7. During this process, the outer liquid flow hole 71 is kept connected to the inner liquid flow hole 81, and the gas inside the air cavity 126 is discharged from the second one-way air outlet pipe 132, and enters the inner limiting sleeve 8 through the connecting hose 83, the inner guide channel 821 inside the inner guide tube 82, the outer guide channel 721 inside the outer guide tube 72 and the outer bubble net 723. The inner bubble net 84 and the outer bubble net 723 move back and forth relative to each other, and the gas is divided to form tiny bubbles inside the inner limiting sleeve 8. Combined with the backwash water circulation, the outside of the filter membrane tube 9 can be flushed with bubbles to enhance the cleaning effect.

[0068] Step B4: After membrane backwashing is completed and before membrane filtration, the drive motor 16 drives the follower wheel 125 to rotate through the drive wheel 15, so that the inner flow limiting sleeve 8 rotates relative to the outer flow limiting sleeve 7, changing the connection state between the outer guide tube 72 and the inner guide tube 82 to a disconnected state.

[0069] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A natural drinking water treatment system, comprising a coarse filter (1) for coarse filtration of water, a fine filter (3) for fine filtration of water, an ultrafiltration membrane filter (4) for ultrafiltration of water, and a disinfection box (6) for ultraviolet disinfection of filtered water, which are connected in sequence, characterized in that: Also included is a backwash water storage tank (5) for backwashing the ultrafiltration membrane filter (4); The ultrafiltration membrane filter (4) is in the shape of an inverted cone, the water inlet pipe (41) of the ultrafiltration membrane filter (4) is tangent to the conical surface of the ultrafiltration membrane filter (4), and a debris removal pipe (42) is provided at the bottom of the ultrafiltration membrane filter (4); An outer flow limiting sleeve (7), an inner flow limiting sleeve (8) and a filter membrane cartridge (9) are coaxially arranged from outside to inside at the middle of the top of the ultrafiltration membrane filter (4); an upper connecting seat (91) at the upper end of the filter membrane cartridge (9) is provided with a water outlet pipe (10); the water outlet pipe (10) is communicated with the backwash water storage tank (5) and the disinfection tank (6) respectively; a central water inlet valve (93) is provided between the lower connecting seat (92) at the lower end of the filter membrane cartridge (9) and the outer flow limiting sleeve (7); the interior of the outer flow limiting sleeve (7) is communicated with the water inlet pipe (41) via a drain pipe (43); The outer flow limiting sleeve (7) and the inner flow limiting sleeve (8) are axially slidably connected, the outer flow limiting sleeve (7) is provided with an outer liquid flow hole (71), and the inner flow limiting sleeve (8) is provided with an inner liquid flow hole (81); When the outer liquid flow hole (71) is in communication with the inner liquid flow hole (81), the central water inlet valve (93) is closed, and the water inside the ultrafiltration membrane filter (4) enters the inner flow limiting sleeve (8) through the outer liquid flow hole (71) and the inner liquid flow hole (81); when the outer liquid flow hole (71) is not in communication with the inner liquid flow hole (81), the central water inlet valve (93) is opened, and the water inside the ultrafiltration membrane filter (4) enters the inner flow limiting sleeve (8) from the bottom of the inner flow limiting sleeve (8); The central water inlet valve (93) comprises a movable blocking ring (931), an elastic member (932), a fixed sleeve (933) and a fixed blocking ring (934); the fixed sleeve (933) is fixedly sleeved on the lower connecting seat (92); the movable blocking ring (931) is axially movable sleeved on the lower connecting seat (92); and the movable blocking ring (931) and the fixed sleeve (933) are connected via the elastic member (932); The fixed blocking ring (934) is coaxially fixedly connected to the interior of the inner flow limiting sleeve (8); the fixed blocking ring (934) and the movable blocking ring (931) are attached to each other to form a closed state of the central water inlet valve (93); the fixed blocking ring (934) and the movable blocking ring (931) are separated to form an open state of the central water inlet valve (93).

2. The natural drinking water treatment system according to claim 1, characterized in that: An isolation cover plate (13) and an upper connecting seat (91) are arranged on the top of the outer current limiting sleeve (7) to form a seal on the upper part of the outer current limiting sleeve (7); An adjusting cylinder (12) is arranged on the upper part of the isolation cover plate (13), a piston plate (121) is arranged inside the adjusting cylinder (12), the lower part of the piston plate (121) is connected to a connecting sleeve (122) that passes through the isolation cover plate (13) and is fixedly connected to the inner flow limiting sleeve (8), the lower part of the piston plate (121) is connected to a connecting rod (124) that passes through the top plate of the adjusting cylinder (12), and the connecting rod (124) is driven by the adjusting cylinder (14) to move up and down; The connecting sleeve (122) is provided with a lower communicating hole (1221) communicating the interior of the inner limiting sleeve (8) with the outer limiting sleeve (7).

3. The natural drinking water treatment system according to claim 2, characterized in that: A liquid level detector (63) is provided on the disinfection box (6), the liquid level detector (63) is connected to the input end of the controller, and the output end of the controller is connected to the regulating cylinder (14); When one of the disinfection boxes (6) reaches the target liquid level, the controller drives the regulating cylinder (14) to perform a driving action, thereby causing the inner flow limiting sleeve (8) to move axially relative to the outer flow limiting sleeve (7) to form a connection or disconnection between the outer liquid flow hole (71) and the inner liquid flow hole (81).

4. The natural drinking water treatment system according to claim 2, characterized in that: An axially extending outer flow guide tube (72) is provided on the inner wall of the outer flow limiting sleeve (7), the lower portion of the outer flow guide tube (72) extends between the inner flow limiting sleeve (8) and the fixed blocking ring (934), and the outer air inlet (722) at the upper portion of the outer flow guide tube (72) is opposite to the outer wall of the inner flow limiting sleeve (8); An axially extending inner flow guide tube (82) is provided on the outer wall of the inner flow limiting sleeve (8), the upper portion of the inner flow guide tube (82) extends between the outer flow limiting sleeve (7) and the connecting sleeve (122), and the inner air outlet (822) at the lower portion of the inner flow guide tube (82) is opposite to the inner wall of the outer flow limiting sleeve (7); The inner flow limiting sleeve (8) is rotatably connected to the outer flow limiting sleeve (7) to form a connection or disconnection between the outer flow guiding tube (72) and the inner flow guiding tube (82).

5. The natural drinking water treatment system according to claim 4, characterized in that: The air cavity (126) at the lower part of the piston plate (121) of the adjustment cylinder (12) is provided with a one-way air inlet pipe (127) and a first one-way air outlet pipe (128); The isolation cover plate (13) is provided with a second one-way air outlet pipe (132), and the second one-way air outlet pipe (132) is connected to the inner flow guide pipe (82) and the air cavity (126) through a connecting hose (83).

6. The natural drinking water treatment system according to claim 5, characterized in that: An outer air bubble net (723) is provided at the outer air outlet at the lower part of the outer flow guide tube (72), and an inner air bubble net (84) is provided at the lower part of the inner flow limiting sleeve (8); when the outer flow guide tube (72) is connected to the inner flow guide tube (82), the inner air bubble net (84) and the outer air bubble net (723) are located in corresponding positions.

7. A treatment process for the natural drinking water treatment system according to claim 2, 3, 4, 5 or 6, comprising the following steps: Step 1: coarsely filter the water through a coarse filter (1); Step 2: Finely filter the water through a fine filter (3); Step 3: performing cross-flow filtration on the water through the filter membrane cartridge (9) of the ultrafiltration membrane filter (4), and performing cross-flow flushing on the outer surface of the filter membrane cartridge (9) during the cross-flow filtration process; Step 4: backwashing the filter membrane cartridge (9) using pure water after membrane filtration, and during the backwashing process, maintaining water pressure inside and outside the filter membrane cartridge (9) to reduce the pressure difference between the inside and outside of the filter membrane cartridge (9); Step 5: Collect the backwash water in step 4 and perform membrane filtration again.

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