Ultrafiltration membrane assembly

Abstract

The invention provides an ultrafiltration membrane assembly. The ultrafiltration membrane assembly comprises an upper water collecting pipe, a lower water collecting pipe and a plurality of filter membrane wires connected between the upper water collecting pipe and the lower water collecting pipe. The upper water collecting pipe comprises a first water collecting channel and a second water collecting channel, the first water collecting channel and the second water collecting channel are arranged in parallel, the two ends of the upper water collecting pipe are connected through a communicating part, and a first gas-liquid channel is formed between the first water collecting channel and the second water collecting channel. The lower water collecting pipe comprises a third water collecting channel and a fourth water collecting channel, the third water collecting channel and the fourth water collecting channel are arranged in parallel, the two ends of the lower water collecting pipe are connected through a communicating part, and a second gas-liquid channel is formed between the third water collecting channel and the fourth water collecting channel. According to the technical scheme, the problem that bubbles in a traditional ultrafiltration membrane assembly need to bypass an arc-shaped water collecting pipe is solved, the bubbles can linearly rise along the gas-liquid channel, the flow direction cannot be changed due to the structure of the water collecting pipe, it is ensured that the bubbles make full contact with all filter membrane wires, and the cleaning effect of gas-water backwashing is improved.

Description

Technical Field

[0001] The present application relates to the technical field of water treatment, and in particular to an ultrafiltration membrane assembly. Background Art

[0002] Curtain membrane technology is a highly efficient water treatment technology that purifies water through the micropores on the membrane surface. It can effectively remove suspended particles, colloids, bacteria and other macromolecular organic matter in the water. During use, the trapped substances will gradually adhere to the inner surface of the membrane, resulting in a decrease in water production, so regular air-water backwashing is required. During the air-water backwashing process, compressed air bubbles in the water can drive the membrane fibers to vibrate, and at the same time, the backwash pump pressurizes purified water to backwash the membrane fibers from the inside of the membrane fibers to the outside, thereby removing pollutants from the surface of the membrane fibers. However, if Figure 1 and Figure 2 As shown in the figure, in the traditional curtain-type ultrafiltration membrane assembly, the bottom of the water collecting pipe is curved and has a large width (about 50 mm). This curtain-type ultrafiltration membrane assembly will cause the rising bubbles to be blocked by the curved water collecting pipe and change the flow direction, so that the bubbles bypass the membrane filaments near the lower water collecting pipe. This not only affects the shaking effect of the bubbles on the space formed between the dense membrane filaments, but also causes the membrane filaments near the lower water collecting pipe that are most contaminated to be unable to be effectively scrubbed by the bubbles, reducing the cleaning effect. Summary of the invention

[0003] The purpose of the present application is to provide an ultrafiltration membrane assembly to solve the technical problems of uneven bubble distribution and unsatisfactory cleaning effect during the air-water backwashing process of the traditional curtain-type ultrafiltration membrane assembly.

[0004] An embodiment of the present application provides an ultrafiltration membrane assembly, comprising an upper water collecting pipe, a lower water collecting pipe and a plurality of filter membrane filaments connected between the upper water collecting pipe and the lower water collecting pipe, wherein the upper water collecting pipe comprises a first water collecting channel and a second water collecting channel, the first water collecting channel and the second water collecting channel are arranged in parallel, the first water collecting channel and the second water collecting channel are connected at both ends of the upper water collecting pipe by a connecting portion, and a first gas-liquid channel is formed between the first water collecting channel and the second water collecting channel; the lower water collecting pipe comprises a third water collecting channel and a fourth water collecting channel, the third water collecting channel and the fourth water collecting channel are arranged in parallel, the third water collecting channel and the fourth water collecting channel are connected at both ends of the lower water collecting pipe by a connecting portion, and a second gas-liquid channel is formed between the third water collecting channel and the fourth water collecting channel, the center lines of the first gas-liquid channel and the second gas-liquid channel are located in the same vertical plane, a bubble uniformizer is arranged in the first gas-liquid channel and the second gas-liquid channel, the bubble uniformizer comprises a plurality of uniform distribution units, and the plurality of the uniform distribution units are arranged at equal intervals along the length direction of the first gas-liquid channel and the second gas-liquid channel.

[0005] In the above ultrafiltration membrane assembly, the connection between the first water collecting channel and the second water collecting channel, and between the third water collecting channel and the fourth water collecting channel are both arc portions.

[0006] In the above ultrafiltration membrane assembly, the bottom of the upper water collecting pipe and the top of the lower water collecting pipe are respectively provided with through holes for installing the filter membrane wires, and the diameter of the through holes is adapted to the outer diameter of the filter membrane wires.

[0007] In the above-mentioned ultrafiltration membrane assembly, each of the evenly distributed units includes a distribution plate, a guide plate and a dirt collecting box, and the distribution plate, the guide plate and the dirt collecting box are arranged in sequence along the air flow direction. The distribution plate is a rectangular plate, and its outer peripheral edge is in contact with the inner wall of the gas-liquid channel. A plurality of through holes are opened on the distribution plate, and the through holes are distributed in a matrix manner on the distribution plate. The distribution plate is divided into a middle area and two side areas along its width direction. The cross-sectional area of ​​the through holes in the middle area is larger than the cross-sectional area of ​​the through holes in the two side areas. The axis of the through hole is parallel to the center line of the gas-liquid channel. The upper and lower ends of the distribution plate extend respectively to form an upper fixed plate and a lower fixed plate. The upper fixed plate and the lower fixed plate are both rectangular plates, parallel to the inner wall of the gas-liquid channel, and threaded holes are opened on the upper fixed plate and the lower fixed plate, and the upper fixed plate and the lower fixed plate are fixed to the inner wall of the gas-liquid channel by fasteners.

[0008] In the above ultrafiltration membrane assembly, an annular sealing ring is provided between the upper fixing plate, the lower fixing plate and the inner wall of the gas-liquid channel, and the annular sealing ring is embedded in the annular groove on the fixing plate.

[0009] In the above-mentioned ultrafiltration membrane assembly, the guide plate is located on the upstream side of the distribution plate and is V-shaped. The opening of the V-shape faces downstream, and the bottom of the V-shape points upstream. The two side edges of the guide plate are fixedly connected to the inner walls of both sides of the gas-liquid channel, and a gap is left between the top of the guide plate and the lower edge of the distribution plate.

[0010] In the above-mentioned ultrafiltration membrane assembly, the dirt collecting box is located on the downstream side of the distribution plate, and has a V-shaped cross-section with the V-shaped opening facing upward. The two ends of the dirt collecting box are fixedly connected to the inner walls of both sides of the gas-liquid channel, and a gap is left between the upper edge of the dirt collecting box and the upper edge of the distribution plate.

[0011] In the above ultrafiltration membrane assembly, a sewage outlet is provided at the bottom of the sewage collecting box, the sewage outlet is connected to the outside through a sewage pipe, and a control valve is provided on the sewage pipe.

[0012] In the above ultrafiltration membrane assembly, the through holes on the distribution plate are arranged in multiple rows and columns, the spacing between two adjacent rows of through holes is equal, and the spacing between two adjacent columns of through holes is equal.

[0013] In the above ultrafiltration membrane assembly, the spacing between any two adjacent uniformly distributed units among the plurality of uniformly distributed units is equal.

[0014] In the ultrafiltration membrane assembly of the present application, the upper water collecting pipe includes a first water collecting channel and a second water collecting channel arranged in parallel, and a first gas-liquid channel is formed therebetween; the lower water collecting pipe includes a third water collecting channel and a fourth water collecting channel arranged in parallel, and a second gas-liquid channel is formed therebetween. The center lines of the first gas-liquid channel and the second gas-liquid channel are located in the same vertical plane, forming a straight channel for bubbles to rise. By respectively arranging two parallel water collecting channels between the upper and lower water collecting pipes, a gas-liquid channel is formed between the water collecting channels, thereby avoiding the problem that bubbles in traditional curtain-type ultrafiltration membrane assemblies need to bypass the arc-shaped water collecting pipe. Bubbles can rise straightly along the gas-liquid channel, and the flow direction will not be changed due to the structure of the water collecting pipe, thereby ensuring full contact between the bubbles and all the filter membrane filaments.

[0015] In addition, since the center lines of the first gas-liquid channel and the second gas-liquid channel are located in the same vertical plane, a stable bubble rising channel is formed. This arrangement makes the movement trajectory of the bubbles more regular and will not deviate, thereby ensuring that the bubbles can be evenly distributed in the space between the filter membrane wires, improving the cleaning effect of the bubbles on the filter membrane wires.

[0016] The above technical solution can make bubbles act evenly on all filter membrane threads, especially for the filter membrane threads close to the lower water collecting pipe, which can also be fully cleaned by bubbles, avoiding the problem of insufficient cleaning of some filter membrane threads in the traditional technical solution. This not only improves the cleaning efficiency, but also prolongs the service life of the filter membrane threads and reduces maintenance costs.

[0017] In summary, the ultrafiltration membrane assembly of the present application effectively solves the problem of uneven bubble distribution in the prior art, significantly improves the cleaning effect of air-water backwashing, and achieves an overall improvement in the performance of the ultrafiltration membrane assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a side view of a traditional curtain type ultrafiltration membrane assembly.

[0019] Figure 2 It is a top view of a traditional curtain-type ultrafiltration membrane assembly.

[0020] Figure 3 It is a schematic diagram of an ultrafiltration membrane assembly provided in an embodiment of the present application.

[0021] Figure 4 yes Figure 3 Side view of the ultrafiltration membrane module shown.

[0022] Figure 5 yes Figure 3 A top view of the ultrafiltration membrane assembly is shown. DETAILED DESCRIPTION

[0023] The specific implementation methods of the present application are described in detail below with reference to the accompanying drawings.

[0024] The terms "first", "second" and similar words do not indicate any order, quantity or importance, but are only used to distinguish different technical features. The term "plurality" and similar words mean two or more, unless otherwise clearly defined.

[0025] The embodiments of the present application may be combined with each other.

[0026] like Figure 3 , Figure 4 and Figure 5 As shown, this embodiment provides an ultrafiltration membrane assembly, including an upper water collecting pipe 101 , a lower water collecting pipe 103 , and a plurality of filter membrane filaments 102 connected between the upper water collecting pipe 101 and the lower water collecting pipe 103 .

[0027] The upper water collecting pipe 101 includes a first water collecting channel 1011 and a second water collecting channel 1012, which are arranged in parallel and have equal cross-sectional areas. The first water collecting channel 1011 and the second water collecting channel 1012 are connected at both ends of the upper water collecting pipe 101 by a connecting portion, and the cross-sectional area of ​​the connecting portion is equal to the cross-sectional area of ​​the water collecting channel. A first gas-liquid channel 1013 is formed between the first water collecting channel 1011 and the second water collecting channel 1012, and the cross-sectional area of ​​the first gas-liquid channel 1013 is rectangular.

[0028] The lower water collecting pipe 103 includes a third water collecting channel 1031 and a fourth water collecting channel 1032, which are arranged in parallel and have equal cross-sectional areas. The third water collecting channel 1031 and the fourth water collecting channel 1032 are connected at both ends of the lower water collecting pipe 103 by a connecting portion, and the cross-sectional area of ​​the connecting portion is equal to the cross-sectional area of ​​the water collecting channel. A second gas-liquid channel 1033 is formed between the third water collecting channel 1031 and the fourth water collecting channel 1032, and the cross-sectional area of ​​the second gas-liquid channel 1033 is rectangular.

[0029] The center lines of the first gas-liquid channel 1013 and the second gas-liquid channel 1033 are located in the same vertical plane. The connection points between the first water collecting channel 1011 and the second water collecting channel 1012 and between the third water collecting channel 1031 and the fourth water collecting channel 1032 are all arc parts.

[0030] A plurality of filter membrane threads 102 are vertically arranged, and the spacing between the filter membrane threads 102 is equal. The bottom of the upper water collecting pipe 101 and the top of the lower water collecting pipe 103 are respectively provided with through holes for installing the filter membrane threads 102, and the diameter of the through holes is adapted to the outer diameter of the filter membrane threads 102.

[0031] In this embodiment, the compressed air 301 provided by the compressed air delivery pipe 201 enters the second gas-liquid channel 1033 from the air inlet at the bottom of the lower water collecting pipe 103. The bubbles of the compressed air 301 rise straight along the second gas-liquid channel 1033, driving the filter membrane filament 102 to shake. At the same time, the backwash pump passes purified water into the filter membrane filament 102 through the water inlet at the top of the upper water collecting pipe 101, and the purified water permeates from the inside of the filter membrane filament 102 to the outside, causing the pollutants on the surface of the filter membrane filament 102 to fall off. The pollutants are discharged from the sewage outlet at the bottom of the lower water collecting pipe 103 along with the bubbles and water flow.

[0032] Although the gas-liquid channel allows the bubbles to fully contact the filter membrane filament 102, in actual applications, when a larger air flow rate is required to enhance the cleaning effect, the gas-liquid channel cannot ensure that the bubbles are evenly distributed over the entire gas-liquid channel cross-section, resulting in excessive concentration of bubbles in some areas and sparse bubbles in some areas, affecting the uniformity of the cleaning effect.

[0033] In order to solve the above problem, a bubble distributor is provided in the first gas-liquid channel 1013 and the second gas-liquid channel 1033 .

[0034] The bubble distributor comprises a plurality of distribution units, which are arranged at equal intervals along the length direction of the first gas-liquid channel and the second gas-liquid channel. Each distribution unit comprises a distribution plate, a guide plate and a dirt collecting box, which are arranged in sequence along the airflow direction.

[0035] The distribution plate is a rectangular plate, and its outer edge is in contact with the inner wall of the gas-liquid channel. A plurality of through holes are provided on the distribution plate, and the through holes are distributed in a matrix on the distribution plate. The distribution plate is divided into three areas along its width direction: the middle area and the two side areas. The cross-sectional area of ​​the through holes in the middle area is larger than the cross-sectional area of ​​the through holes in the two side areas. The axes of all through holes are parallel to the center line of the gas-liquid channel. The through holes form a matrix of multiple rows and columns on the distribution plate.

[0036] The upper end and the lower end of the distribution plate extend to form an upper fixing plate and a lower fixing plate, respectively. The upper fixing plate and the lower fixing plate are both rectangular plates, and are parallel to the inner wall of the gas-liquid channel. A threaded hole is provided on each of the upper fixing plate and the lower fixing plate. The upper fixing plate and the lower fixing plate are fixed to the inner wall of the gas-liquid channel by fasteners. An annular sealing ring is provided between the upper fixing plate and the lower fixing plate and the inner wall of the gas-liquid channel, and the annular sealing ring is embedded in the annular groove on the fixing plate.

[0037] The guide plate is located on the upstream side of the distribution plate and is V-shaped, with the opening of the V facing downstream and the bottom of the V pointing upstream. The two sides of the guide plate are fixedly connected to the inner walls of the gas-liquid channel on both sides. A gap is left between the top of the guide plate and the lower edge of the distribution plate. The surface of the guide plate is smooth.

[0038] The dirt collecting box is located on the downstream side of the distribution plate, and its cross section is V-shaped, with the V-shaped opening facing upward. The two ends of the dirt collecting box are fixedly connected to the inner walls of the gas-liquid channel on both sides. A gap is left between the upper edge of the dirt collecting box and the upper edge of the distribution plate. A drain port is provided at the bottom of the dirt collecting box, and the drain port is connected to the outside through a drain pipe. A control valve is provided on the drain pipe.

[0039] In actual operation, when bubbles rise from the bottom, they are first dispersed by the guide plate, and the bubbles flow along the inclined surface of the guide plate to both sides, covering the entire cross-section of the distribution plate. Then the bubbles pass through the through holes on the distribution plate. Due to the different cross-sectional areas of the through holes in the middle area and the two side areas, the bubbles are evenly distributed on the cross-section of the gas-liquid channel. After being dispersed step by step by multiple uniformly distributed units, evenly distributed bubbles are finally formed in the entire gas-liquid channel. At the same time, the dirt that falls off the surface of the filter membrane filament 102 is collected in the dirt collection box and discharged through the sewage outlet and the sewage pipe.

[0040] Through the above improvements, the bubble distributor solves the problem of uneven distribution of bubbles in the gas-liquid channel by using the cooperation of the distribution plate, the guide plate and the dirt collection box. The partitioned through holes of the distribution plate make the bubbles evenly distributed, the guide plate makes the bubbles fully dispersed, and the dirt collection box prevents the distribution plate from being blocked, thereby improving the uniformity of the cleaning effect, extending the maintenance cycle of the equipment, and improving the operating stability of the equipment.

[0041] The spacing between adjacent filter membrane filaments 102 is small. In actual operation, if the raw water quality is poor and contains more large particles of impurities, under high flow conditions, these impurities may get stuck between the filter membrane filaments 102, causing local blockage, reducing the filtration efficiency of the ultrafiltration membrane assembly, and even damaging the filter membrane filaments 102.

[0042] In order to solve the above problems, a pre-filter is provided at the water inlet end of the ultrafiltration membrane assembly.

[0043] The pre-filter comprises a housing and a multi-layer filter member arranged in the housing. The housing comprises an upper housing and a lower housing, and the upper housing and the lower housing are detachably connected by a quick connection member. The quick connection member comprises an annular flange arranged on the outer periphery of the lower housing and a plurality of buckles arranged on the outer periphery of the upper housing, and the buckles are detachably buckled with the annular flange.

[0044] The shell is cylindrical, the water inlet end of the shell is connected to the water inlet pipe, and the water outlet end is connected to the water inlet of the ultrafiltration membrane assembly. The cross-sectional area of ​​the shell is larger than the cross-sectional area of ​​the water inlet pipe, forming an expansion part.

[0045] The multi-layer filter components are arranged in sequence along the water flow direction, and there are intervals between adjacent filter components. Each layer of the filter component includes a filter body and a fixing ring. The filter body is folded and cylindrical after folding. The fixing ring is arranged at both ends of the filter body, and a sealing ring is arranged on the outer periphery of the fixing ring, and the sealing ring is in sealing contact with the inner wall of the shell.

[0046] A support ring is arranged between adjacent filter components, the outer diameter of the support ring matches the inner diameter of the shell, and a plurality of water holes are arranged on the support ring, which are distributed in a ring array.

[0047] A flow guide is provided at the water inlet end of the shell, and the flow guide comprises a plurality of flow guide plates, and the plurality of flow guide plates are radially distributed. One end of each flow guide plate is fixedly connected to the inner wall of the shell, and the other end points to the axis of the shell.

[0048] A rectifying plate is arranged downstream of the last layer of filtering components, and a plurality of water holes are opened on the rectifying plate, and the water holes are distributed in a matrix. The outer periphery of the rectifying plate is fixedly connected to the inner wall of the shell.

[0049] The bottom of the shell is provided with a sewage outlet, and the sewage outlet is provided with a first control valve. The top of the shell is provided with an exhaust port, and the exhaust port is provided with a second control valve.

[0050] A first pressure detection port and a second pressure detection port are respectively provided at the water inlet end and the water outlet end of the shell, and the first pressure detection port and the second pressure detection port are respectively connected to the pressure sensor.

[0051] In actual operation, the raw water enters the shell after being dispersed by the guide, and then passes through the multi-layer filter components in sequence, and large particles of impurities are intercepted step by step. Since the filter body adopts a folded structure, it has a large filtering area and is not prone to overall clogging. The support ring prevents the filter component from deforming, and the rectifier plate allows the filtered water to flow evenly into the ultrafiltration membrane assembly.

[0052] Through the above improvements, the pre-filter can effectively intercept large particles of impurities in the raw water, prevent the impurities from clogging the gaps between the filter membrane filaments 102, protect the filter membrane filaments 102, improve the filtration efficiency, and extend the service life of the ultrafiltration membrane assembly.

[0053] When the filter needs to be cleaned, first close the water inlet valve and the water outlet valve, open the sewage valve and the exhaust valve, and discharge the water and gas in the shell. Then, loosen the buckle connection with the annular flange, remove the upper shell, and take out the filter element for cleaning or replacement.

[0054] Through the above improvements, the pre-filter utilizes the step-by-step filtration of the multi-layer filter components to prevent large particles from entering the ultrafiltration membrane assembly and avoid clogging between the filter membrane filaments 102. The split structure of the housing and the quick connection components facilitate maintenance and cleaning, and the pressure sensor can detect the clogging of the filter components in time, thereby improving the operational reliability of the equipment.

[0055] The inner surfaces of the first gas-liquid channel 1013 and the second gas-liquid channel 1033 are smooth surfaces. When the ultrafiltration membrane assembly vibrates or the water flow rate changes, the gas and liquid are easily separated, resulting in the inability of the bubbles to stably contact the filter membrane filament 102, affecting the cleaning effect.

[0056] In order to solve the above problem, flow guiding concave-convex surfaces are provided on the inner surfaces of the first gas-liquid channel 1013 and the second gas-liquid channel 1033 .

[0057] The flow guiding concave-convex surface includes a first texture group and a second texture group. The first texture group extends along the length direction of the gas-liquid channel, and the second texture group extends along the circumference direction of the gas-liquid channel. The first texture group and the second texture group are interlaced to form a grid.

[0058] The first texture group includes a plurality of parallel first grooves, and first ridges are formed between adjacent first grooves. The cross section of the first groove is V-shaped, and the opening of the V-shape faces the center of the gas-liquid channel. The extension direction of the first groove is parallel to the rising direction of the bubble, so as to guide the bubble to move along a predetermined path.

[0059] The second texture group includes a plurality of parallel second grooves, and second ridges are formed between adjacent second grooves. The cross section of the second groove is V-shaped, and the opening of the V-shape faces the center of the gas-liquid channel. The second groove is perpendicular to the first groove to increase the interface area of ​​gas-liquid contact, so that the interaction between gas and liquid is more sufficient.

[0060] The intersection of the first groove and the second groove forms a cavity, and the bottom surface of the cavity is spherical. These cavities can act as micro gas storage chambers, which help stabilize the movement of bubbles. When encountering unstable factors during the rising process of bubbles, the gas stored in the cavity can provide certain support and stability for the bubbles. The intersection of the first convex ridge and the second convex ridge forms a boss, and the top surface of the boss is an arc surface. These bosses can increase the disturbance between gas and liquid, effectively prevent gas-liquid stratification, and allow gas and liquid to mix more evenly.

[0061] The concave and convex guide surface forms a repeating unit on the inner surface of the gas-liquid channel, each repeating unit includes four concave cavities, four bosses, a first groove section and a second groove section. The multiple repeating units are evenly distributed along the circumference and axial direction of the gas-liquid channel.

[0062] Through the above improved structure, the concave and convex guide surface increases the gas-liquid contact area and stabilizes the bubble movement. The concave cavity can store gas and provide gas replenishment when the bubble movement is unstable; the convex platform can disturb the gas-liquid flow and prevent gas-liquid stratification; the first groove guides the bubble to rise, and the second groove increases the gas-liquid mixing, which improves the contact stability between the bubble and the filter membrane filament 102.

[0063] In order to further enhance the gas-liquid mixing effect, guide surfaces are provided on the side walls of the first groove and the second groove. The guide surfaces are arranged alternately along the length direction of the groove to form a sawtooth shape. The inclination directions of adjacent guide surfaces are opposite. When the bubbles pass through the guide surfaces, a rotation motion is generated, thereby enhancing the gas-liquid mixing effect, allowing the bubbles to contact the liquid more fully, and improving the uniformity of the gas-liquid mixing.

[0064] At the turning point of the gas-liquid channel, the distribution density of the concave and convex surfaces of the flow guide is different. The spacing of the repeating units on the inner side of the turning point is smaller than that on the outer side. This differentiated setting can compensate for the uneven distribution of bubbles at the turning point caused by factors such as centrifugal force, ensuring that the bubbles can also be distributed more evenly at the turning point.

[0065] In actual operation, when the ultrafiltration membrane assembly vibrates or the water flow velocity changes, the bubbles come into contact with the concave and convex surfaces of the flow guide during the rising process. The grooves and bosses increase the gas-liquid contact area, making the movement of the bubbles more stable. The grid-like distribution prevents the bubbles from aggregating or dispersing, maintaining the uniformity of the bubble distribution.

[0066] When the bubbles pass through the cavity, part of the gas is retained in the cavity to form an air reservoir. When the main airflow is unstable, the air reservoir releases the bubbles to maintain the continuity of the bubble distribution.

[0067] The guide surface causes the bubbles to rotate, preventing them from moving along a fixed path, so that the bubbles can more fully contact various parts of the filter membrane filament 102, thereby improving the cleaning effect. The differentiated setting at the turning point makes the bubbles evenly distributed, avoiding the problem of uneven bubble distribution caused by centrifugal force.

[0068] This improvement solves the gas-liquid separation problem through the concave and convex guide surface, ensuring stable contact between the bubbles and the filter membrane filament 102. The concave and convex guide surface increases the friction and contact area between the gas and liquid, allowing the bubbles to rise stably and fully contact the filter membrane filament 102. The combination of the cavity, the boss and the guide surface enhances the gas-liquid mixing effect and maintains the stability of the bubble distribution. The special distribution at the turning point optimizes the uniformity of the bubble distribution and avoids affecting the cleaning effect due to uneven local bubble distribution.

[0069] In actual operation, in order to effectively remove pollutants on the surface of the filter membrane filament 102, the backwash pump usually pressurizes the purified water to backwash from the inside of the filter membrane filament 102 to the outside. When the backwash pressure is high, the filter membrane filament 102 may be damaged due to excessive pressure, reducing the service life and filtration performance of the ultrafiltration membrane assembly. For example, when treating highly polluted water, a higher pressure backwash is often required to achieve a better cleaning effect, and the risk of damage to the filter membrane filament 102 is significantly increased.

[0070] In order to solve the above problems, the structure of the filter membrane filament 102 is improved. The filter membrane filament 102 includes an inner support layer, a middle filter layer and an outer protective layer, and the three layers are sequentially coated and arranged.

[0071] The inner support layer is in the shape of a hollow tube, and its inner wall is a smooth surface to reduce the resistance of water flow inside. The outer wall of the inner support layer is provided with a protrusion, and the protrusion is arranged in a spiral shape along the axial direction. The spiral protrusion increases the contact area between the inner support layer and the middle filter layer, making the combination between the two closer. At the same time, the spiral protrusion can also guide the backwash water flow to form a spiral motion, thereby enhancing the backwash effect. The cross section of the protrusion is semicircular, and the height of the protrusion remains consistent along the axial direction.

[0072] In order to further improve the compressive performance of the filter membrane filament 102, a reinforcement portion is provided on the inner wall of the inner support layer, and the reinforcement portion includes a plurality of annular reinforcement ribs. The annular reinforcement ribs are evenly spaced along the axial direction, and the cross section of each annular reinforcement rib is triangular. The base of the triangle is fixedly connected to the inner wall of the inner support layer, and the vertex of the triangle points to the central axis of the inner support layer. The triangular cross-sectional structure has good stability, can evenly bear radial pressure, and prevent local deformation of the membrane filament during high-pressure backwashing.

[0073] The middle filter layer is coated on the outer surface of the inner support layer and fits closely with the raised part of the inner support layer to ensure that no stratification occurs under the backwash pressure. The middle filter layer is provided with through holes, which are distributed in a mesh pattern to achieve effective filtration of impurities in the water. The thickness of the middle filter layer is uniform along the axial direction of the membrane, ensuring the consistency of the filtration performance.

[0074] The outer protective layer is coated on the outer surface of the middle filter layer. The outer protective layer includes a first reinforcing rib group and a second reinforcing rib group, the first reinforcing rib group extends in the axial direction, and the second reinforcing rib group extends in the circumferential direction. The first reinforcing rib group and the second reinforcing rib group are interwoven to form a grid, and the middle filter layer is exposed at the opening of the grid, which ensures the protective effect of the outer protective layer on the middle filter layer without affecting the filtering function of the middle filter layer.

[0075] A reinforcement node is provided at the intersection of the first reinforcement rib group and the second reinforcement rib group. The reinforcement node is truncated cone-shaped, and the large end of the truncated cone is connected to the reinforcement rib. Adjacent reinforcement nodes are connected by reinforcement ribs to form an overall mesh structure. The thickness of the reinforcement node is greater than the thickness of the reinforcement rib. This design significantly increases the overall strength of the filter membrane filament 102, enabling it to withstand higher backwash pressure.

[0076] The surface of the outer protective layer is provided with guide grooves. The guide grooves are distributed in a spiral shape along the axial direction, and the spiral direction of the guide grooves is opposite to the spiral direction of the raised part of the inner support layer, so as to form a complex eddy field during the backwashing process, enhance the cleaning effect, and disperse the local pressure to avoid damage to the membrane filaments caused by excessive local pressure. The cross section of the guide groove is arc-shaped, and the arc opening faces outward.

[0077] Reinforced sections are provided at both ends of the filter membrane filament 102, and the length of the reinforced sections accounts for one tenth of the total length of the membrane filament. In the reinforced sections, the wall thickness of the inner support layer gradually increases from the middle to the end, and the grid spacing of the outer protective layer gradually decreases from the middle to the end, forming a gradient structure. This avoids damage caused by stress concentration at both ends of the membrane filament, and improves the strength of the filter membrane filament 102 at the connection with the water collection channel.

[0078] In order to prevent the filter membrane wire 102 from twisting and deforming during the backwashing process, the first reinforcing rib group and the second reinforcing rib group adopt an interlaced braiding structure. Adjacent first reinforcing ribs are interlaced and connected by the second reinforcing ribs to form a three-dimensional mesh structure. In the interlaced braiding structure, the intersections of the first reinforcing ribs and the second reinforcing ribs are provided with reinforcing nodes. This interlaced braiding structure provides good torsion resistance, so that the filter membrane wire 102 can maintain a stable shape during the high-pressure backwashing process.

[0079] In actual operation, when the backwash pressure acts on the inner wall of the inner support layer, the annular reinforcement ribs bear radial pressure to prevent local deformation of the membrane filaments. The spiral protrusions of the inner support layer work closely with the middle filter layer to guide the water flow to form a spiral motion and improve the backwash efficiency. The mesh structure and the guide groove of the outer protective layer work together to form a complex flow field and enhance the cleaning effect. The gradient structure and staggered braiding structure of the reinforcement section provide overall support to keep the filter membrane filament 102 stable during high-pressure backwashing.

[0080] The middle filter layer fits tightly with the inner support layer, and will not be delaminated under the backwash pressure, ensuring the stability of the filtering function. The mesh structure of the outer protective layer supports the middle filter layer and prevents it from over-expanding.

[0081] The spiral guide grooves on the surface of the outer protective layer and the spiral protrusions of the inner supporting layer are arranged in opposite directions, so that the backwash water flow forms a vortex when passing through the membrane filaments, which not only enhances the cleaning effect but also disperses the local pressure and effectively protects the filter membrane filaments 102.

[0082] The reinforcement sections at both ends are designed with a gradual structure to avoid stress concentration and improve the strength of the filter membrane wire 102 at the connection. At the same time, the interlaced woven reinforcement rib structure provides good torsion resistance, so that the filter membrane wire 102 remains stable during high-pressure backwashing and is not prone to twisting and deformation.

[0083] This improvement significantly improves the mechanical strength of the filter membrane filament 102, enabling it to withstand higher backwash pressures without breaking. The annular reinforcement ribs and spiral protrusions of the inner support layer, the close fit between the intermediate filter layer and the inner support layer, the mesh structure, reinforcement nodes and spiral guide grooves of the outer protective layer, as well as the reinforcement sections and staggered braided structure, work together to ensure the stability and reliability of the filter membrane filament 102 under high-pressure backwashing. While maintaining good filtering performance, the service life of the filter membrane filament 102 is greatly extended, the replacement cost and equipment downtime caused by the damage of the filter membrane filament 102 are reduced, the overall operating efficiency and economy of the ultrafiltration membrane assembly are improved, and the stable operation of the ultrafiltration membrane assembly in scenarios requiring high-pressure backwashing, such as treating highly polluted water, is guaranteed.

[0084] During actual operation, when the flow of compressed air 301 is unstable or the ultrafiltration membrane assembly stops running, water may accumulate in the first gas-liquid channel 1013 and the second gas-liquid channel 1033. The accumulated water will occupy the space of the gas-liquid channel, affecting the subsequent circulation of compressed air 301, and further affecting the shaking and cleaning effect of the bubbles on the filter membrane filament 102, thereby reducing the overall cleaning efficiency of the ultrafiltration membrane assembly.

[0085] In order to solve the above problem, drainers are provided at the bottom of the first gas-liquid channel 1013 and the second gas-liquid channel 1033 .

[0086] The drainer includes a water collecting chamber, a drain pipe and a control valve group. The water collecting chamber is set at the lowest point of the gas-liquid channel and is funnel-shaped. The upper part is connected to the gas-liquid channel and the lower part is connected to the drain pipe. The inner wall of the water collecting chamber is provided with a spiral guide groove. This structure can guide the accumulated water to flow downward along the spiral path and effectively prevent the accumulated water from flowing back. The top of the water collecting chamber and the inner wall of the gas-liquid channel form an arc transition part to avoid the generation of vortexes and ensure that the accumulated water can flow smoothly into the water collecting chamber.

[0087] The drainage pipe includes a main pipe and a branch pipe. The main pipe is vertically arranged, with the upper end connected to the bottom of the water collection chamber and the lower end extending to the outside of the ultrafiltration membrane assembly. The branch pipe is horizontally arranged, intersecting with the main pipe, and is used to install the control valve group.

[0088] The control valve group includes a valve body, a valve core and a drive unit. The valve body is set at the intersection of the main pipe and the branch pipe, and the valve core moves back and forth in the valve body. The valve core includes a main valve core and a secondary valve core. The main valve core is used to control drainage, and the secondary valve core is used to prevent gas backflow.

[0089] A liquid level gauge is provided in the water collecting chamber, and the liquid level gauge includes a float and a guide rod. The float moves up and down along the guide rod, and the guide rod is fixed to the inner wall of the water collecting chamber. The position change of the float is transmitted to the control valve group through the connecting rod.

[0090] In order to prevent gas leakage during drainage, the drainer is provided with a sealing member. The sealing member includes a first sealing ring and a second sealing ring. The first sealing ring is arranged between the main valve core and the valve body, and the second sealing ring is arranged between the auxiliary valve core and the valve body. The first sealing ring moves with the main valve core, and the second sealing ring is fixed in the valve body.

[0091] A noise reducer is provided at the outlet of the main pipe. The noise reducer includes a shell and a multi-layer partition disposed in the shell. The partitions are arranged in a maze-like manner to form a tortuous channel to reduce the noise generated during drainage. The shell is connected to the main pipe by threads.

[0092] An observation window is arranged in the middle of the main pipe. The observation window is embedded in the side wall of the main pipe, and a sealing ring is arranged between the observation window and the main pipe. The sealing ring is placed in the annular groove.

[0093] In actual operation, when water accumulates in the gas-liquid channel, the accumulated water first enters the water collecting chamber and flows downward along the spiral guide groove. When the accumulated water reaches the set position, the float rises, drives the main valve core downward through the connecting rod, opens the drainage channel, and the accumulated water is discharged under the action of gravity. The auxiliary valve core remains closed to prevent gas leakage from the drainage channel.

[0094] The sealing component ensures the air tightness of the system, and there will be no gas leakage even under high pressure. When the accumulated water is discharged, the float drops, the main valve core closes, and the drainage cycle is completed.

[0095] This improved structure achieves automatic drainage of water accumulated in the gas-liquid channel through the cooperation of the water collecting chamber and the sealing component, while avoiding gas leakage. The spiral guide groove of the water collecting chamber guides the accumulated water to flow in an orderly manner, preventing backflow and turbulence, improving drainage efficiency and stability. The liquid level meter cooperates with the control valve group to achieve automatic drainage without manual intervention, reducing labor costs and water accumulation problems caused by untimely human operation. The sealing component prevents gas leakage.

[0096] At high altitudes, the atmospheric pressure is low, and after the compressed air 301 enters the gas-liquid channel, the rising speed and distribution of the bubbles are affected. Due to the reduced air density, the bubbles cannot provide enough power to drive the filter membrane filament 102 to vibrate during the rising process, resulting in a poor cleaning effect, which in turn affects the operating efficiency of the ultrafiltration membrane assembly.

[0097] In order to solve the above problem, an air supercharger is arranged on the air intake pipeline (the pipeline before the compressed air 301 enters the gas-liquid channel). The air supercharger includes a pressure boosting component, a pressure stabilizing component and a regulating component, and the three components are connected by flanges.

[0098] The pressure boosting component comprises a shell and a supercharger arranged in the shell. The shell is cylindrical, and its air inlet end is connected to an external air source, and its air outlet end is connected to the pressure stabilizing component.

[0099] The supercharger includes a power component and a transmission component. The power component is fixed on the support seat at the bottom of the shell and connected to the transmission component through a coupling. The transmission component includes a driving shaft and a driven shaft, and the driving shaft and the driven shaft are driven by a synchronous belt. A guide track is set on the inner wall of the shell, and the guide track extends along the axial direction of the shell. The supercharger component slides with the guide track through a slider to ensure the movement stability during the supercharging process, making the supercharging operation more stable and reliable.

[0100] The pressure stabilizing component includes a gas storage tank and a plurality of interfaces arranged on the gas storage tank. The gas storage tank is in a horizontal cylindrical shape, and both ends thereof are provided with elliptical heads to improve the pressure bearing capacity of the gas storage tank. The air inlet of the gas storage tank is connected to the air outlet end of the pressure boosting component, and the air outlet is connected to the regulating component.

[0101] The top of the gas tank is equipped with a safety valve and a pressure gauge interface. The safety valve is used to automatically release pressure when the pressure in the gas tank is too high to ensure system safety; the pressure gauge interface can be connected to a pressure gauge to monitor the pressure in the gas tank in real time. A drain valve is provided at the bottom of the gas tank to facilitate the discharge of impurities and moisture accumulated in the gas tank. Multiple guide plates are set inside the gas tank. The guide plates are wavy to slow down the air flow speed, make the pressure distribution more uniform, and ensure the stability of the gas pressure entering the regulating component.

[0102] The regulating member includes a valve body and a regulating mechanism disposed in the valve body. The valve body is Y-shaped, one end of which is connected to the gas storage tank, and the other end is divided into two branches, leading to the first gas-liquid channel 1013 and the second gas-liquid channel 1033 respectively.

[0103] The regulating mechanism includes a main valve core and a sub-valve core. The main valve core is used to control the total flow, and the sub-valve core is used to control the flow distribution of the two branches. Both the main valve core and the sub-valve core are conical structures, and precise adjustment is achieved through a screw mechanism. In this way, the gas flow entering the two gas-liquid channels can be accurately adjusted according to actual needs to ensure uniform distribution of bubbles.

[0104] A buffer cavity is provided at the outlet of the regulating component, and a multi-layer rectifying mesh plate is provided in the buffer cavity. The rectifying mesh plate is honeycomb-shaped to eliminate the turbulence of the air flow, make the bubble distribution more uniform, and further optimize the gas state entering the gas-liquid channel.

[0105] In order to achieve automatic control, the ultrafiltration membrane assembly also includes pressure sensors installed at the inlet and outlet of the boosting component, liquid level sensors installed on the gas storage tank, flow sensors installed on the regulating component, etc. These sensors are electrically connected to the controller, and the controller automatically adjusts the operating parameters of the system according to the signals from the sensors. For example, when insufficient outlet pressure is detected, the controller will automatically increase the operating power of the boosting component; when the liquid level in the gas storage tank is too high, the controller will sound an alarm or control related equipment to perform operations such as drainage.

[0106] During actual operation, the external gas source first enters the boosting component, and the pressurized gas enters the gas tank for temporary storage. The guide plate in the gas tank is used to reduce the air flow velocity and make the pressure distribution uniform. When the gas flows out of the gas tank, it enters the two gas-liquid channels respectively after precise adjustment by the regulating component. The regulating component is used to adjust the total flow and distribution ratio according to actual needs to ensure that the bubbles in the two gas-liquid channels are evenly distributed. The rectifier mesh of the buffer cavity further optimizes the airflow state, so that the bubbles entering the gas-liquid channel are uniform in size and stably distributed. This multi-stage processing method ensures that even in high-altitude environments, the bubbles can still provide sufficient power to drive the filter membrane filament 102 to shake.

[0107] This improvement effectively solves the problem of reduced operating efficiency in high-altitude areas through the synergistic effects of multiple links such as pressurization, voltage stabilization, and regulation. The pressurization component increases the pressure of the compressed air 301 entering the gas-liquid channel, making up for the lack of low atmospheric pressure in high-altitude areas, and ensuring that the bubbles have sufficient power to drive the filter membrane filament 102 to shake. The pressure stabilization component stabilizes the gas pressure through the gas storage tank and the guide plate, provides a stable gas source for the adjustment component, and ensures the stability of the operation of the entire system. The adjustment component can accurately control the gas flow and distribution ratio, so that the bubbles are evenly distributed in the two gas-liquid channels, improving the cleaning effect. The buffer cavity and the rectifier mesh plate further optimize the airflow state to ensure that the bubbles enter the gas-liquid channel stably and evenly. Through these improvements, the ultrafiltration membrane assembly can maintain a stable operating effect under different altitude environments, expand its scope of application, improve the working efficiency and reliability in high-altitude areas, and ensure that the ultrafiltration membrane assembly can operate efficiently in various complex environments.

[0108] In the ultrafiltration membrane assembly of the present application, the upper water collecting pipe 101 includes a first water collecting channel 1011 and a second water collecting channel 1012 arranged in parallel, and a first gas-liquid channel 1013 is formed between the two; the lower water collecting pipe 103 includes a third water collecting channel 1031 and a fourth water collecting channel 1032 arranged in parallel, and a second gas-liquid channel 1033 is formed between the two. The center lines of the first gas-liquid channel 1013 and the second gas-liquid channel 1033 are located in the same vertical plane, forming a straight channel for the bubbles to rise. By respectively arranging two parallel water collecting channels between the upper and lower water collecting pipes 103, a gas-liquid channel is formed between the water collecting channels, thereby avoiding the problem that the bubbles in the traditional curtain ultrafiltration membrane assembly need to bypass the arc-shaped water collecting pipe. The bubbles can rise straightly along the gas-liquid channel, and the flow direction will not be changed due to the structure of the water collecting pipe, thereby ensuring that the bubbles are in full contact with all the filter membrane filaments 102.

[0109] In addition, since the center lines of the first gas-liquid channel 1013 and the second gas-liquid channel 1033 are located in the same vertical plane, a stable bubble ascending channel is formed. This arrangement makes the movement trajectory of the bubbles more regular and will not deviate, thereby ensuring that the bubbles can be evenly distributed in the space between the filter membrane threads 102, thereby improving the cleaning effect of the bubbles on the filter membrane threads 102.

[0110] The above technical solution can make bubbles act evenly on all filter membrane threads 102, especially for the filter membrane threads 102 close to the lower water collecting pipe 103, which can also be fully cleaned by bubbles, thus avoiding the problem of insufficient cleaning of some filter membrane threads 102 in the traditional technical solution. This not only improves the cleaning efficiency, but also prolongs the service life of the filter membrane threads 102 and reduces the maintenance cost.

[0111] In summary, the ultrafiltration membrane assembly of the present application effectively solves the problem of uneven bubble distribution in traditional technologies, significantly improves the cleaning effect of air-water backwashing, and achieves an overall improvement in the performance of the ultrafiltration membrane assembly.

[0112] The embodiments of the present application are described in detail above, and the contents of this specification should not be construed as limiting the scope of protection of the present application.

Claims

1. An ultrafiltration membrane assembly, comprising an upper water collecting pipe, a lower water collecting pipe and a plurality of filter membrane wires connected between the upper water collecting pipe and the lower water collecting pipe, characterized in that: The upper water collecting pipe includes a first water collecting channel and a second water collecting channel, the first water collecting channel and the second water collecting channel are arranged in parallel, the first water collecting channel and the second water collecting channel are connected by a connecting part at both ends of the upper water collecting pipe, and a first gas-liquid channel is formed between the first water collecting channel and the second water collecting channel; the lower water collecting pipe includes a third water collecting channel and a fourth water collecting channel, the third water collecting channel and the fourth water collecting channel are arranged in parallel, the third water collecting channel and the fourth water collecting channel are connected by a connecting part at both ends of the lower water collecting pipe, and a second gas-liquid channel is formed between the third water collecting channel and the fourth water collecting channel, the center lines of the first gas-liquid channel and the second gas-liquid channel are located in the same vertical plane, and a bubble uniformizer is arranged in the first gas-liquid channel and the second gas-liquid channel, and the bubble uniformizer includes a plurality of uniform distribution units, and the plurality of the uniform distribution units are arranged at equal intervals along the length direction of the first gas-liquid channel and the second gas-liquid channel.

2. The ultrafiltration membrane assembly according to claim 1, characterized in that: The connection between the first water collecting channel and the second water collecting channel, and between the third water collecting channel and the fourth water collecting channel are both arc portions.

3. The ultrafiltration membrane assembly according to claim 1, characterized in that: The bottom of the upper water collecting pipe and the top of the lower water collecting pipe are respectively provided with through holes for installing filter membrane threads, and the diameter of the through holes is matched with the outer diameter of the filter membrane threads.

4. The ultrafiltration membrane assembly according to claim 1, characterized in that: Each of the evenly distributed units includes a distribution plate, a guide plate and a dirt collecting box, which are arranged in sequence along the airflow direction. The distribution plate is in the shape of a rectangular plate, and its outer peripheral edge is in contact with the inner wall of the gas-liquid channel. A plurality of through holes are provided on the distribution plate, and the through holes are distributed in a matrix manner on the distribution plate. The distribution plate is divided into a middle area and two side areas along its width direction. The cross-sectional area of ​​the through holes in the middle area is larger than the cross-sectional area of ​​the through holes in the two side areas. The axis of the through hole is parallel to the center line of the gas-liquid channel. The upper and lower ends of the distribution plate extend respectively to form an upper fixing plate and a lower fixing plate, and the upper fixing plate and the lower fixing plate are both in the shape of rectangular plates, which are parallel to the inner wall of the gas-liquid channel. A threaded hole is provided on each of the upper fixing plate and the lower fixing plate, and the upper fixing plate and the lower fixing plate are fixed to the inner wall of the gas-liquid channel by fasteners.

5. The ultrafiltration membrane assembly according to claim 4, characterized in that: An annular sealing ring is arranged between the upper fixing plate, the lower fixing plate and the inner wall of the gas-liquid channel, and the annular sealing ring is embedded in the annular groove on the fixing plate.

6. The ultrafiltration membrane assembly according to claim 4, characterized in that: The guide plate is located on the upstream side of the distribution plate and is V-shaped, with the opening of the V-shape facing downstream and the bottom of the V-shape pointing upstream. The two side edges of the guide plate are fixedly connected to the inner walls of the gas-liquid channel on both sides, and a gap is left between the top of the guide plate and the lower edge of the distribution plate.

7. The ultrafiltration membrane assembly according to claim 4, characterized in that: The dirt collecting box is located on the downstream side of the distribution plate, and has a V-shaped cross section with the V-shaped opening facing upward. The two ends of the dirt collecting box are fixedly connected to the inner walls of both sides of the gas-liquid channel, and a gap is left between the upper edge of the dirt collecting box and the upper edge of the distribution plate.

8. The ultrafiltration membrane assembly according to claim 7, characterized in that: The bottom of the sewage collecting box is provided with a sewage outlet, the sewage outlet is communicated with the outside through a sewage pipe, and a control valve is provided on the sewage pipe.

9. The ultrafiltration membrane assembly according to claim 4, characterized in that: The through holes on the distribution plate are arranged in multiple rows and columns, and the spacing between two adjacent rows of through holes is equal, and the spacing between two adjacent columns of through holes is equal.

10. The ultrafiltration membrane assembly according to claim 4, characterized in that: The spacing between any two adjacent evenly distributed units among the plurality of evenly distributed units is equal.

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