Cross-flow filtration control method and system

Abstract

The present invention belongs to the technical field of water separation, and specifically relates to a cross-flow filtration control method and system. The filter unit of the cross-flow filtration system is divided into a raw water chamber and a filter water chamber by a filter membrane. The vibrator arranged in the filter water chamber forms a circulation system with an external water tank through a power pump, so that the power pump can supply filtered water to the vibrator. The vibrator includes a shell and a plurality of vibration generating assemblies distributed on the shell and close to one side of the filter membrane, so that the vibration generating assemblies can all be in elastic contact with the filter membrane. The cavity water inlet end of the shell is connected to the power pump, so that the power pump can pump in and out filtered water or continuously pump in filtered water into the cavity to cause the vibration generating assembly to oscillate. The vibration generating assembly oscillates to arouse the filter membrane to vibrate. The present invention can cause the filter membrane to vibrate, so as to strengthen the shear force of the fluid acting on the surface of the filter membrane and increase the difficulty of solid particles adhering to the surface of the filter membrane, thereby delaying the formation speed of the dirt layer on the surface of the filter membrane.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage separation, and in particular to a cross-flow filtration control method and system. Background Art

[0002] As a commonly used sewage treatment technology, cross-flow filtration makes the flow direction of raw water (sewage or feed liquid) tangent to the membrane surface direction of the filter membrane during operation, and can rely on the shear force generated when the raw water flows through the membrane surface to carry away the large particles of dirt retained on the membrane surface and enter the circulation channel with the raw water, which can keep the dirt layer on the membrane surface at a relatively thin level, effectively inhibit the blockage of the gaps on filter membranes such as ceramic membranes, and keep the membrane assembly at a relatively high permeation flux and separation efficiency for a long time. Although cross-flow filtration itself has the ability to clean up the dirt attached to the membrane surface in real time, after a long period of operation, the thickness of the dirt layer attached to the filter membrane will continue to increase, causing the blockage of the gaps on the filter membrane to gradually increase, and eventually affecting the permeation flux and separation efficiency of the filter membrane, and developing to a state where it cannot operate normally. Therefore, whether it is cross-flow filtration or ordinary membrane filtration, it is inevitable that a dirt layer will form on the surface of the filter membrane.

[0003] In the prior art, the main ways to reduce or remove the dirt attached to the membrane surface include enhancing the flow kinetic energy of raw water, regular backwashing, special treatment of the filter membrane surface to increase the difficulty of dirt attachment, adding chemical reagents to the raw water to slow down particle precipitation, etc. The specific method or methods to be adopted needs to be determined according to the specific working conditions, raw water conditions and other factors. Among them, enhancing the kinetic energy of raw water and backwashing are the two most commonly used methods. Therefore, delaying the formation speed of the fouling layer on the membrane surface and reducing the frequency of membrane cleaning are the technical directions for continuous improvement and enhancement in membrane filtration technology. Summary of the invention

[0004] The present invention provides a cross-flow filtration control method and system, which can cause the filter membrane to vibrate during the cross-flow filtration process to strengthen the shear force of the fluid on the filter membrane surface, increase the difficulty of solid particles adhering to the filter membrane surface, and slow down the formation speed of the dirt layer on the filter membrane surface.

[0005] The technical solution adopted by the present invention to achieve its technical purpose is: a cross-flow filtration system, including a raw water tank, a water supply pump arranged on the outlet pipeline of the raw water tank, at least one circulation pump arranged on the output pipeline of the water supply pump, a filter unit matched one-to-one with the circulation pump, an external water tank, at least one power pump matched on the output pipeline of the external water tank, a vibrator matched one-to-one with the filter unit, and a control unit.

[0006] The inlet end of the raw water chamber of the filter unit cavity is connected to the drainage end of the corresponding circulation pump, and the outlet end is matched with a concentrate outlet pipe, and the concentrate outlet pipe is connected to the inlet pipeline of the raw water tank through the concentrate return pipe, and a return branch pipe is provided on the concentrate return pipe, so that the return branch pipe is connected between the water outlet end of the water supply pump and the water inlet end of the circulation pump.

[0007] The vibrator is fixedly arranged in the water filter cavity of the filter unit cavity. The outlet end of the water filter cavity of the filter unit cavity is connected to the external water tank. The output end of the power pump is connected to the vibrator. The control unit is connected to the power pump and can adjust the operating state of the power pump to make the vibrator oscillate.

[0008] The vibrator comprises a shell and a plurality of vibration generating assemblies distributed on the shell and on a wall surface close to one side of the filter membrane, so that the vibration generating assemblies can contact with the filter membrane and exert elastic pushing force on the filter membrane.

[0009] The water inlet end of the cavity of the outer shell is connected to the power pump, and the control unit can make the power pump cyclically pump in and out filtered water into the cavity to cause the vibration generating assembly to oscillate; or the water inlet end of the cavity of the outer shell is connected to the power pump, and the water outlet end is connected to the water inlet end of the external water tank, and the control unit can make the power pump continuously pump filtered water into the cavity of the outer shell to cause the vibration generating assembly to oscillate.

[0010] When the vibration generating assembly oscillates, the elastic thrust force exerted on the filter membrane can stimulate the filter membrane to vibrate, and can cause the filter membrane to bounce a certain amplitude between the original water chamber and the filtered water chamber.

[0011] Optionally, the water inlet end of the cavity of the housing is connected to the power pump, and the cavity is not provided with a water outlet end or a drainage end, and is a single-port cavity structure. When the control unit drives the power pump to cyclically pump filtered water into and out of the cavity, the internal pressure of the cavity can be changed, and each vibration generating assembly can be caused to oscillate. At this time, the vibration generating assembly includes a plurality of elastic capsule walls distributed on the top wall of the housing, a connecting spring and a balloon body.

[0012] The elastic capsule wall protrudes outward relative to the outer end of the top wall of the shell. One end of the connecting spring is fixedly connected to the top of the elastic capsule wall, and the other end is fixedly connected to the balloon body. The control unit controls the power pump to cyclically pump filtered water into and out of the cavity, which can change the internal pressure of the cavity and cause the elastic capsule wall to deform elastically, thereby driving the connecting spring to pull the balloon body to push the filter membrane, thereby achieving the purpose of driving the filter membrane to bounce between the original water cavity and the filtered water cavity.

[0013] Furthermore, one end of the balloon body that matches the connecting spring is an open end, and a plurality of through holes are distributed on the balloon wall of the balloon body.

[0014] Optionally, the water inlet end of the cavity of the shell is connected to the power pump, and the water outlet end is connected to the water inlet end of the external water tank, forming a dual-port cavity structure. The vibration generating assemblies are distributed alternately along the length direction of the cavity. When the control unit drives the power pump to continuously pump filtered water into the cavity of the shell, the filtered water flow formed in the cavity can disturb each vibration generating assembly to produce oscillation. At this time, the vibration generating assembly includes a spoiler, a top plate fixed at one end of the spoiler, and at least one contact arm fixed at the free end of the spoiler.

[0015] A plurality of support arm plates are formed on the top plate on the side away from the top wall of the housing. The support arm plates can relatively fix the top plate in the cavity and make the top plate contact the top wall of the housing. The width of the top plate is consistent with the width of the cavity, so the filtered water will be blocked by the top plate in the flow direction. The width of the spoiler is not greater than the width of the cavity, and preferably the difference between the width of the cavity and the width of the spoiler is in the range of 0 mm to 4 mm.

[0016] The free end of the spoiler extends obliquely toward the side close to the inner bottom surface of the cavity, so that the cross section of the channel between the spoiler and the inner bottom surface of the cavity gradually decreases in the flow direction of the filtered water. Therefore, in the flow direction of the filtered water in the cavity, the filtered water can flow through the gap between two adjacent support arm plates, and then when flowing through the channel / flow channel formed between the spoiler and the inner bottom surface of the cavity, the fluid can generate disturbances.

[0017] An elastic wall portion is formed on the spoiler at the position where the spoiler is connected to the top plate. The elastic wall portion extends along the width direction of the spoiler. The elastic wall portion can cause the spoiler to elastically deform at its root, so that the free end of the spoiler can reciprocate and swing between the inner top surface and the inner bottom surface of the cavity.

[0018] On the top wall of the housing, there are through slots corresponding to the contact arms, and an elastic membrane that can cover the opening of the through slot can be provided in the through slot. The free end of the contact arm extends out of the cavity and leans against the filter membrane, and the middle of the contact arm is fixedly connected to the elastic membrane.

[0019] Furthermore, wedge-shaped protrusions matching the spoiler are distributed on the inner bottom surface of the cavity, and the wedge-shaped protrusions are relatively arranged on the downstream side of the free end of the spoiler, and the inclined upward end of the wedge-shaped protrusions is relatively away from the free end of the spoiler.

[0020] Furthermore, a plurality of transverse channels are distributed on the outer shell of the vibrator, and at least one cavity is formed on the transverse channel.

[0021] The length extension direction of the transverse channel is consistent with the length direction of the water filter chamber. Multiple transverse channels are distributed alternately and a spacing area is formed between two adjacent transverse channels, and the width of the spacing area is not less than the width of the transverse channel. After assembly, a spacing is formed between each transverse channel and the opposite surface of the filter membrane.

[0022] The present invention relates to a cross-flow filtration control method, which is mainly based on the above-mentioned cross-flow filtration system. Specifically, an external water tank is connected to the filtered water outlet pipe of the filter unit, and a power pump is provided on the outlet pipe of the external water tank. The power pump matches the vibrator arranged in the filter water cavity of the filter unit, and the vibrator can contact the membrane surface of the filter membrane in the filter unit. When the control unit controls the power pump to run, the power pump can drive the filtered water to continuously induce the vibrator to oscillate, so that the vibrator excites the filter membrane to vibrate, and the membrane body of the filter membrane vibrates and bounces between the raw water cavity and the filtered water cavity, so as to cause the raw water flowing through the membrane surface near the filter membrane to oscillate, forming a local oscillating flow. The oscillating flow generated by the raw water fluid can strengthen the instantaneous shear force of the raw water acting on the filter membrane during the flow process, and can enhance the flushing ability of the raw water on the filter membrane surface. In addition, the vibration of the membrane body itself can also achieve the purpose of inhibiting the solid particles in the raw water from adhering to the filter membrane surface, thereby effectively delaying the formation speed of the dirt layer on the filter membrane surface.

[0023] The beneficial effects of the present invention are as follows: when the present invention is used for cross-flow filtration operations, the filter membrane is caused to vibrate to strengthen the shear force of the fluid acting on the surface of the filter membrane, and at the same time, the difficulty of solid particles in the raw water adhering to the surface of the filter membrane is increased, so as to significantly slow down the formation speed of the dirt layer on the surface of the filter membrane, prevent the micropores of the filter membrane from being blocked prematurely, extend the effective filtration time of the filter membrane, reduce the cleaning frequency and relatively increase the filtration flux of the filter membrane during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0025] Figure 2 It is a schematic cross-sectional structure diagram of the first embodiment of the vibrator-related part of the present invention.

[0026] Figure 3 for Figure 2 Schematic diagram of the local enlarged structure at point A in the middle.

[0027] Figure 4 It is a schematic cross-sectional structure diagram of the second embodiment of the vibrator-related part of the present invention.

[0028] Figure 5 for Figure 4 Schematic diagram of the local enlarged structure at point B in the middle.

[0029] Figure 6for Figure 4 Schematic diagram of the local enlarged structure at point C in the middle.

[0030] Figure 7 A schematic diagram of the vibrator structure from a top view.

[0031] In the figure: 100 raw water tank; 200 water supply pump; 300 circulation pump, 301 circulation pump 1, 302 circulation pump 2; 400 filter unit, 401 filter unit 1, 402 filter unit 2; 500 concentrated water outlet pipe, 501 concentrated water outlet pipe 1, 502 concentrated water outlet pipe 2, 503 concentrated water return pipe, 504 return branch pipe; 600 filtered water outlet pipe; 700 external water tank, 701 power pump; 10 filter unit Elementary cavity, 11 raw water cavity, 12 water filtration cavity; 20 filter membrane; 30 vibrator, 31 shell, 3.1 transverse channel, 3.2 spacer area, 311 through slot hole, 312 elastic diaphragm, 32 cavity, 321 wedge-shaped protrusion, 33 vibration generating assembly, 331 elastic capsule wall, 332 connecting spring, 333 balloon body; 334 spoiler, 335 top plate, 336 elastic wall part, 337 contact arm, 338 support arm plate. DETAILED DESCRIPTION

[0032] The structures, proportions, sizes, etc. illustrated in the drawings of the specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical contents disclosed by the present invention. At the same time, the terms such as "upper", "lower", "front", "back", "middle" and so on quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the present invention without substantially changing the technical contents.

[0033] like Figures 1 to 6 A cross-flow filtration system is shown, comprising a raw water tank 100, a water supply pump 200 arranged on the outlet pipeline of the raw water tank 100, two circulation pumps 300 arranged on the output pipeline of the water supply pump 200, two filter units 400 matched one-to-one with the two circulation pumps 300, an external water tank 700, two power pumps 701 matched on the output pipeline of the external water tank 700, vibrators 30 matched one-to-one with the filter units 400, and a control unit (not shown in the figure).

[0034] The two circulation pumps 300 are respectively circulation pump 1 301 and circulation pump 2 302, and the two filter units 400 are respectively filter unit 1 401 and filter unit 2 402. The circulation pump 1 301 is matched with the filter unit 1 401, and the circulation pump 2 302 is matched with the filter unit 2 402. The filter unit cavity 10 of the filter unit 1 401 and the filter unit 2 402 is divided into an upper and lower cavity by a filter membrane 20, and the two cavities are respectively a raw water cavity 11 and a filtered water cavity 12.

[0035] The inlet end of the raw water chamber 11 is connected to the drainage end of the corresponding circulating pump 300, and the outlet end is matched with a concentrated water outlet pipe 500. The concentrated water outlet pipes 500 corresponding to the two filter units 400 shown in the figure are concentrated water outlet pipe 1 501 and concentrated water outlet pipe 2 502. The concentrated water outlet pipe 1 501 and concentrated water outlet pipe 2 502 are connected in parallel to the concentrated water return pipe 503, and are connected to the inlet pipeline of the raw water tank 100 through the concentrated water return pipe 503. A return branch pipe 504 is provided on the concentrated water return pipe 503, and the return branch pipe 504 is connected between the water outlet end of the water supply pump 200 and the water inlet ends of the circulating pump 1 301 and the circulating pump 2 302, so that the circulating pump 1 301 and the circulating pump 2 302 can obtain circulating raw water from the water supply pump 200 and the return branch pipe 504 at the same time. The power pump 701 can be selected as a diaphragm pump or other pumps of different forms.

[0036] In the water filter chamber 12 on the two filter units 400, one vibrator 30 is fixedly arranged respectively. The outlet end of the water filter chamber 12 is provided with a water filter outlet pipe 600, so that at least one of the water filter outlet pipes 600 is connected to the external water tank 700, so that the external water tank 700 can obtain the water filter medium from the water filter chamber 12. The output ends of the two power pumps 701 are respectively connected to the two vibrators 30. The control unit is respectively connected to the two power pumps 701, and can respectively adjust the operating states of the two power pumps 701 to drive the two vibrators 30 to oscillate respectively.

[0037] like Figures 2 to 7 As shown, the vibrator 30 includes a shell 31 and a plurality of vibration generating assemblies 33 distributed on the shell 31 and on the wall surface close to one side of the filter membrane 20, so that the vibration generating assembly 33 can contact the filter membrane 20 (the membrane surface on the side of the water filter chamber 12) and exert an elastic pushing effect on the filter membrane 20 to cause the filter membrane 20 to vibrate / bounce, and the swing direction of the vibration / bounce occurs between the side of the water filter chamber 12 and the side of the raw water chamber 11.

[0038] The water inlet end on the cavity 32 of the outer shell 31 is connected to the power pump 701, and the control unit can drive the power pump 701 to cyclically pump and pump out filtered water into and out of the cavity 32 regularly to cause the vibration generating assembly 33 to oscillate, which is one implementation scenario; or the water inlet end on the cavity 32 of the outer shell 31 is connected to the power pump 701, and the water outlet end is connected to the water inlet end of the external water tank 700, and the control unit can drive the power pump 701 to continuously pump filtered water into the cavity 32 of the outer shell 31 to cause the vibration generating assembly 33 to oscillate, which is another implementation scenario.

[0039] In the first embodiment, the cavity 32 is generally provided with only a water inlet port, which is a single-port cavity. In the second embodiment, the cavity 32 is provided with a water inlet port and a water outlet port, which is a double-port cavity, and the two ports can make the filtered water entering the cavity 32 flow from a certain side (such as the left side) to the opposite side (such as the right side), thereby forming a unidirectional liquid flow.

[0040] When the vibration generating assembly 33 oscillates, the elastic thrust force applied to the filter membrane 20 can cause the filter membrane 20 to vibrate, and can cause the filter membrane 20 to bounce / vibrate with a certain amplitude between the raw water chamber 11 side and the filtered water chamber 12 side.

[0041] like Figure 2 , Figure 3 As shown, the water inlet end of the cavity 32 of the housing 31 is connected to the power pump 701, and the cavity 32 is not provided with a water outlet end or a drainage end, and is a single-port cavity structure. When the control unit drives the power pump 701 to cyclically pump filtered water into and out of the cavity 32, the internal pressure of the cavity 32 can be caused to change regularly, and each vibration generating assembly 33 can be caused to oscillate, and the vibration generating assembly 33 can be specifically designed as follows.

[0042] The vibration generating assembly 33 includes a plurality of elastic capsule walls 331, a connecting spring 332 and a balloon body 333 distributed on the top wall of the housing 31. The elastic capsule wall 331 protrudes outward (toward the upper side) relative to the outer end surface (the upper end surface in the figure) of the top wall of the housing 31. One end (lower end) of the connecting spring 332 is fixedly connected to the top of the elastic capsule wall 331, and the other end (upper end) is fixedly connected to the balloon body 333.

[0043] When the control unit drives the power pump 701 to cyclically pump filtered water into and out of the cavity 32, the (liquid) internal pressure of the cavity 32 can change regularly, thereby causing the elastic sac wall 331 to undergo regular (expansion and contraction) elastic deformation, thereby driving the connecting spring 332 to pull the balloon body 333 to push the filter membrane 20, thereby achieving the purpose of driving the filter membrane 20 to bounce between the raw water cavity 11 side and the filtered water cavity 12 side.

[0044] The elastic capsule wall 331 can be a convex capsule body with convex points or a long strip convex capsule body. When a convex capsule body with convex points is selected, the number of the connecting springs 332 matches the elastic capsule wall 331 one by one, and the spherical capsule body 333 matches the connecting springs 332 one by one. When a long strip convex capsule body is selected, the length direction of the elastic capsule wall 331 should be consistent with the length direction of the cavity 32 or the length direction of the shell 31, for example Figure 2 In the illustrated case, each length direction is along the left-right direction. At this time, on the elastic capsule wall 331 , a plurality of connecting springs 332 and a spherical capsule body 333 corresponding to the connecting springs 332 are alternately distributed along the length direction of the elastic capsule wall 331 .

[0045] In order to increase the vibration intensity of the balloon body 333 so as to arouse the filter membrane 20 to vibrate strongly, the end of the balloon body 333 that matches the connecting spring 332 is made an open end, and a plurality of through holes are distributed on the balloon body 333 .

[0046] During the elastic deformation of the elastic bladder wall 331, the spherical body 333 will be pulled by the connection spring 332 and move, and the filtered water poured into the spherical body 333 will continuously flow through the through holes on the spherical body wall of the spherical body 333, and can exert liquid disturbance force on the spherical body 333. Because the connection between the spherical body 333 and the elastic bladder wall 331 is a flexible connection, the pulling effect of the elastic bladder wall 331 and the disturbance effect of the filtered water will cause the spherical body 333 to swing irregularly and strongly, so that the top curved surface of the spherical body 333 and the non-fixed position on the membrane surface of the filter membrane 20 (shown as the lower membrane surface in the figure) will have elastic impact contact, which can cause the filter membrane 20 to vibrate significantly and disorderly, and can strengthen the disturbance ability of the liquid flow near the filter membrane 20 in the raw water chamber 11, so as to increase the shear force of the raw water on the filter membrane 20.

[0047] like Figures 4 to 6As shown, the water inlet end of the cavity 32 of the housing 31 is connected to the power pump 701, and the water outlet end is connected to the water inlet end of the external water tank 700, forming a dual-port cavity structure. The vibration generating assemblies 33 are arranged alternately along the length direction of the cavity 32 (left and right directions in the figure). When the control unit drives the power pump 701 to continuously pump filtered water into the cavity 32 of the housing 31, the filtered water flow formed in the cavity 32 can disturb each vibration generating assembly 33 to generate oscillation, which is used to excite the filter membrane 20 to generate vibration.

[0048] The vibration generating assembly 33 includes a spoiler 334 , a top plate 335 fixedly disposed at one end (left end) of the spoiler 334 , and at least one contact arm 337 fixedly disposed at a free end of the spoiler 334 .

[0049] Two support arm plates 338 are formed on the side of the top plate 335 away from the top wall of the housing 31. The support arm plates 338 can relatively fix the top plate 335 in the cavity 32 and make the top plate 335 contact the top wall of the housing 31 (or contact the inner top surface of the cavity 32). The width of the top plate 335 is consistent with the width of the cavity 32. Therefore, in the flow direction, the filtered water will be blocked by the top plate 335 at the upper part of the cavity 32 (the side of the cavity 32 close to the filter membrane 20). The width of the spoiler 334 is not greater than the width of the cavity 32, and it is preferred that the difference between the width of the cavity 32 and the width of the spoiler 334 is in the range of 0 mm to 2 mm.

[0050] The free end of the spoiler 334 extends obliquely toward the side close to the inner bottom surface of the cavity 32, so that the channel cross section between the spoiler 334 and the inner bottom surface of the cavity 32 gradually decreases in the flow direction of the filtered water.

[0051] At that time, in the flow direction of the filtered water in the cavity 32, the filtered water can flow through the gap between the two support arm plates 338, and then flow through the channel / flow channel formed between the spoiler 334 and the bottom surface of the cavity 32, and form significant spoiler / turbulence.

[0052] An elastic wall portion 336 is formed on the spoiler 334 at the position where the spoiler 334 is connected to the top plate 335. The elastic wall portion 336 extends along the width direction of the spoiler 334. The elastic wall portion 336 can cause the spoiler 334 to elastically deform at its root, so that the free end of the spoiler 334 can reciprocate and swing between the inner top surface and the inner bottom surface of the cavity 32.

[0053] On the top wall of the housing 31 , there are through slots 311 corresponding to and matching the contact arms 337 , and inside the through slots 311 there are elastic diaphragms 312 that can cover the openings of the through slots 311 .

[0054] The free end of the contact arm 337 extends out of the cavity 32 and is close to the filter membrane 20, and the vertical distance between the free end of the contact arm 337 and the membrane surface of the filter membrane 20 is controlled within a range of 0.5 mm to 3 mm. The middle portion of the contact arm 337 is fixedly connected to the elastic diaphragm 312.

[0055] As the power pump 701 continuously supplies the filtered water in the external water tank 700 to the cavity 32, a filtered water flow will be formed in the length direction of the cavity 32. When the filtered water flow encounters the spoiler 334 during the flow, the flow will be disturbed because the flow cross section gradually decreases, which can cause the free end of the spoiler 334 to swing back and forth between the inner top surface and the inner bottom surface of the cavity 32. As the spoiler 334 swings, the contact arm 337 will also swing synchronously, pulling the elastic diaphragm 312 to elastically deform. The elastic deformation of the elastic diaphragm 312 will form an elastic force that drives the spoiler 334 to rebound, which helps to enhance the vibration intensity of the free end of the contact arm 337, increase the vibration frequency, and increase the intensity of the elastic impact between the free end of the contact arm 337 and the filter membrane 20, which can arouse the filter membrane 20 to vibrate or oscillate significantly.

[0056] When the elastic diaphragm 312 is not provided in the through slot hole 311, the contact arm 337 directly passes through the through slot hole 311, and the free end of the contact arm 337 extends outside the cavity 32 and the free end of the contact arm 337 is close to the membrane surface of the filter membrane 20, and the vertical distance between the two is generally controlled within the range of 0.5mm to 2mm. In this implementation state, the cross section of the through slot hole 311 should not be too large, so as to suppress the amount of filtered water in the cavity 32 flowing to the filter cavity 12, and to reduce the influence of the connection between the through slot hole 311 and the filter cavity 12 on the flow of filtered water in the cavity 32. On the contrary, when the elastic diaphragm 312 is provided, the cross section of the through slot hole 311 should be relatively large, so that the elastic diaphragm 312 has a relatively large plane area, and can relatively easily undergo a more significant elastic deformation, and finally achieve the elastic force of the elastic diaphragm 312 participating in and affecting the oscillation process of the spoiler 334.

[0057] In order to further increase the oscillation intensity of the spoiler 334 aroused by the filtered water flow in the cavity 32, a wedge-shaped protrusion 321 corresponding to the spoiler 334 is distributed on the inner bottom surface of the cavity 32, and the wedge-shaped protrusion 321 is relatively arranged on the downstream side of the free end of the spoiler 334, and the inclined upward end (i.e., the relatively protruding end) of the wedge-shaped protrusion 321 is relatively away from the free end of the spoiler 334, see Figure 5 , Figure 6 shown.

[0058] like Figure 7 As shown, a plurality of transverse channels 3.1 are formed on the vibrator 30, so that the length extension direction of the transverse channels 3.1 is consistent with the length direction of the water filter chamber 12. The power pump 701 can supply filtered water to the plurality of transverse channels 3.1 at the same time. The plurality of transverse channels 3.1 are distributed alternately, and a spacing area 3.2 is formed between two adjacent transverse channels 3.1 (i.e., a rectangular through-hole structure is formed), so that the membrane surface of the filter membrane 20 and the water filter chamber 12 can be well connected, and the setting of the vibrator 30 will not affect / block the flow of the produced filtered water into the water filter chamber 12. The width of the spacing area 3.2 is not less than the width of the transverse channel 3.1.

[0059] Each transverse channel 3.1 contains at least one cavity 32, and the length direction of the transverse channel 3.1 is consistent with the length direction of the cavity 32. When the vibration generating assembly 33 contains the elastic capsule wall 331, the balloon bodies 333 are alternately distributed outside the transverse channel 3.1 along its length direction. When the vibration generating assembly 33 contains the spoiler 334, multiple ends of the contact arms 337 are alternately distributed along the length direction of the transverse channel 3.1 protrude from the outside of the transverse channel 3.1.

[0060] The vibrator 30 may be in the form of a plate, and correspondingly, the filter membrane 20 is a plate-shaped membrane. In this case, a plane on one side of the vibrator 30 is arranged opposite to a membrane surface (a plane) on one side of the filter membrane 20, and a vertical spacing / gap is formed between the opposite planes. The vibrator 30 may also be in the form of a ring, and correspondingly, the filter membrane 20 is an annular membrane. In this case, the vibrator 30 is sleeved outside the filter membrane 20, and the inner peripheral surface of the vibrator 30 is arranged opposite to the outer peripheral surface of the filter membrane 20, and a radial spacing / gap is formed between the opposite peripheral surfaces.

[0061] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. The present invention can be improved in many aspects without violating the overall concept, and those familiar with the technology can modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A cross-flow filtration system, comprising a raw water tank (100), a water supply pump (200) provided on an outlet pipeline of the raw water tank (100), at least one circulating pump (300) provided on an output pipeline of the water supply pump (200), and a filter unit (400) corresponding to and matching the circulating pump (300); a filter unit cavity (10) of the filter unit (400) is divided into a raw water cavity (11) and a filtered water cavity (12) by a filter membrane (20); the raw water cavity ( 11) the inlet end is connected to the drainage end of the circulation pump (300), the outlet end is matched with a concentrated water outlet pipe (500) and the concentrated water outlet pipe (500) is connected to the inlet pipeline of the raw water tank (100) through the concentrated water return pipe (503), and a return water branch pipe (504) is provided on the concentrated water return pipe (503), so that the return water branch pipe (504) is connected between the water outlet end of the water supply pump (200) and the water inlet end of the circulation pump (300); the characteristics are: It also comprises an external water tank (700), at least one power pump (701) matched with the output pipeline of the external water tank (700), a vibrator (30) matched with the filter unit (400), and a control unit; the vibrator (30) is fixedly arranged in the water filter chamber (12) and the outlet end of the water filter chamber (12) is connected to the external water tank (700); the output end of the power pump (701) is connected to the vibrator (30); the control unit is connected to the power pump (701) and can adjust the operating state of the power pump (701); The vibrator (30) comprises a housing (31) and a plurality of vibration generating assemblies (33) distributed on the housing (31) and on a wall surface close to a side of the filter membrane (20), so that the vibration generating assemblies (33) can all come into contact with the filter membrane (20); The water inlet end of the cavity (32) of the housing (31) is connected to the power pump (701), and the control unit can control the power pump (701) to pump filtered water into and out of the cavity (32) to cause the vibration generating assembly (33) to oscillate; or the water inlet end of the cavity (32) of the housing (31) is connected to the power pump (701), and the water outlet end is connected to the water inlet end of the external water tank (700), so that the control unit can control the power pump (701) to continuously pump filtered water into the cavity (32) to cause the vibration generating assembly (33) to oscillate; When the vibration generating assembly (33) generates oscillations, it can cause the filter membrane (20) to vibrate.

2. The cross-flow filtration system according to claim 1, characterized in that: The water inlet end of the cavity (32) of the housing (31) is connected to the power pump (701); the vibration generating assembly (33) comprises a plurality of elastic bladder walls (331) distributed on the top wall of the housing (31), and a connecting spring (332) and a spherical bladder body (333); The elastic capsule wall (331) protrudes outwardly relative to the outer end of the top wall of the cavity (32); one end of the connecting spring (332) is fixedly connected to the top of the elastic capsule wall (331), and the other end is fixedly connected to one end of the balloon body (333); The power pump (701) is used to cyclically pump filtered water into and out of the cavity (32), thereby causing the elastic sac wall (331) to undergo elastic deformation, thereby driving the connecting spring (332) to pull the sac body (333) to push against the filter membrane (20) to cause vibration.

3. The cross-flow filtration system according to claim 2, characterized in that: The end of the balloon body (333) that matches the connecting spring (332) is an open end, and a plurality of through holes are distributed on the balloon wall of the balloon body (333).

4. The cross-flow filtration system according to claim 1, characterized in that: The water inlet end of the cavity (32) of the housing (31) is connected to the power pump (701), and the water outlet end is connected to the water inlet end of the external water tank (700); the vibration generating assembly (33) is arranged alternately along the length direction of the cavity (32); the vibration generating assembly (33) comprises a spoiler (334), a top plate (335) fixedly arranged at one end of the spoiler (334), and at least one contact arm (337) fixedly arranged at the free end of the spoiler (334); The top plate (335) is fixed on the inner top surface of the cavity (32), and the width of the top plate (335) is consistent with the width of the cavity (32); the width of the spoiler (334) is not greater than the width of the cavity (32); The free end of the spoiler (334) extends obliquely toward a side close to the inner bottom surface of the cavity (32); an elastic wall portion (336) is formed on the spoiler (334) at a position where the spoiler (334) is connected to the top plate (335); the elastic wall portion (336) is extended along the width direction of the spoiler (334), so that the spoiler (334) can be elastically deformed at its root; A through slot hole (311) corresponding to and matching each contact arm (337) is provided on the top wall of the housing (31); After the free end of the contact arm (337) passes through the through slot hole (311), it extends out of the cavity (32) with the end thereof close to the filter membrane (20).

5. The cross-flow filtration system according to claim 4, characterized in that: An elastic diaphragm (312) capable of sealing the notch of the through-slot hole (311) is provided in the through-slot hole (311); the middle portion of the contact arm (337) is fixedly connected to the elastic diaphragm (312).

6. The cross-flow filtration system according to claim 4 or 5, characterized in that: A plurality of support arm plates (338) are formed on a side of the top plate (335) facing away from the top wall of the housing (31); the support arm plates (338) can relatively fix the top plate (335) in the cavity (32) and enable the top plate (335) to contact the inner top surface of the cavity (32).

7. The cross-flow filtration system according to claim 4 or 5, characterized in that: The difference between the width of the cavity (32) and the width of the spoiler (334) is in the range of 0 mm to 4 mm.

8. The cross-flow filtration system according to claim 4 or 5, characterized in that: A wedge-shaped protrusion (321) corresponding to and matching the spoiler (334) is distributed on the inner bottom surface of the cavity (32), and the wedge-shaped protrusion (321) is relatively arranged on the downstream side of the free end of the spoiler (334), and the inclined surface upstream end of the wedge-shaped protrusion (321) is relatively away from the free end of the spoiler (334).

9. The cross-flow filtration system according to claim 1, characterized in that: A plurality of transverse channels (3.1) are distributed and formed on the outer shell (31) of the vibrator (30), and at least one cavity (32) is formed on the transverse channel (3.1); The length extension direction of the transverse channel (3.1) is consistent with the length direction of the water filter chamber (12); the plurality of transverse channels (3.1) are distributed alternately and a spacing area (3.2) is formed between two adjacent transverse channels (3.1); and the width of the spacing area (3.2) is not less than the width of the transverse channel (3.1).

10. A cross-flow filtration control method based on the cross-flow filtration system according to any one of claims 1 to 9, characterized in that: When cross-flow filtration is performed, the control unit controls the operating state of the power pump (701) to drive the vibrator (30) to continuously oscillate, thereby exciting the filter membrane (20) to vibrate, and causing the flowing raw water to oscillate near the membrane surface of the filter membrane (20).

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