Water circulation treatment system for spunlace production line

Abstract

The invention relates to a water circulation treatment system for a spunlace production line, and relates to the field of wastewater multi-stage treatment.The water circulation treatment system comprises a rotary drum filter, a flocculation device, a multi-medium filter, an MBR membrane bioreactor, an ultrafiltration device and a pH adjusting pond, the multi-medium filter comprises a shell, a plurality of filter material layers, an upper separation net, a lower separation net, a backwashing water cap plate and a transfer backwashing assembly; a through hole communicated to the transfer space penetrates through the side wall of the shell, the transfer backwashing assembly enters the transfer space through the through hole, and the shell is movably connected with a sealing cover used for blocking the through hole; the backwashing water cap plate is positioned at the bottom of the shell; the transfer backwashing assembly is provided with a water return cavity and a backwashing cavity which are independent from each other, the backwashing cavity is communicated with the upper half part of the transfer space, the water return cavity is communicated with the lower half part of the transfer space, the backwashing cavity is communicated with a discharge pipe, and the water return cavity is communicated with a discharge pipe. According to the multi-medium filter, the backwashing effect on each filter material layer can be improved, so that the filtering effect of the multi-medium filter is improved.

Description

Technical Field

[0001] The present application relates to the field of multi-stage wastewater treatment, and particularly to a water circulation treatment system for a spunlace production line. Background Art

[0002] Spunlace non-woven fabric is made by spraying high-pressure micro water jets onto one or more fiber webs, so that the fibers are entangled with each other, thereby strengthening the fiber web to have a certain strength, and the obtained fabric is spunlace non-woven fabric.

[0003] The spunlace process relies on high-pressure water needles (200 - 600 bar) to impact the fiber web to entangle the fibers, with extremely high water consumption (about 50 - 150 tons of water per ton of product), and the sprayed wastewater contains a large amount of fibers, oil agents, impurity particles, pigments, etc. Therefore, a water circulation treatment system needs to be equipped. The water circulation treatment system is reused after collection, filtration, and purification, which can reduce the fresh water consumption by more than 90%, significantly save production costs, or treat the wastewater to the discharge standard for discharge.

[0004] The existing water circulation treatment system includes a drum filter, a flocculation device, a multi-media filter, an MBR membrane bioreactor, an ultrafiltration device, and a pH adjustment tank. Among them, the existing multi-media filter includes a housing, a multi-layer filter media layer, and a backwash water cap plate. The backwash water cap plate is located directly below the filter media layer. Wastewater is discharged from the upper end of the housing, and the wastewater passes through the filtration and adsorption of the multi-layer filter media layer in sequence and is discharged from the lower end of the housing.

[0005] After being used for a period of time, the filter media layer becomes clogged, and its filtering and adsorption effect deteriorates. Then the backwash water cap plate performs backwashing upwards, and the backwash water passes through each filter media layer from bottom to top in sequence to wash away the impurities in the filter media layer and discharge them from the upper end of the housing.

[0006] In order to ensure the filtering effect of the filter media layer, the filter media in the filter media layer is often relatively dense, and the filter media is also prone to caking due to impurities. Therefore, during the upward movement of the backwash water, the water pressure loss is large, and it is difficult for the backwash water to wash away the impurities in the filter media layer at a higher position. Moreover, impurities are also carried upwards during the upward movement of the backwash water. When the upward movement path of the impurities is too long, the impurities are easily intercepted by the filter media in the filter media layer at a higher position, resulting in incomplete washing of the impurities and a high residual rate, thereby affecting the filtering effect of the filter after backwashing. Summary of the Invention

[0007] In order to improve the backwash effect to improve the filtering effect, the present application provides a water circulation treatment system for a spunlace production line.

[0008] A water circulation treatment system for a spunlace production line provided by the present application adopts the following technical solutions: A water circulation treatment system for a hydrospinning production line, successively including a rotary drum filter, a flocculation device, a multi-media filter, an MBR membrane bioreactor, an ultrafiltration device and a pH adjustment tank. The multi-media filter includes a housing, a plurality of filter media layers, an upper partition net, a lower partition net, a backwash water cap plate and a transfer backwash assembly. An inlet pipe and a sewage discharge pipe are provided at the upper end of the housing, and a drain pipe is provided at the lower end of the housing. The filter media layers are arranged vertically at intervals. The upper partition net is attached to the upper surface of the filter media layer, and the lower partition net supports the lower surface of the filter media layer. The vertical gap between the adjacent lower partition net and the upper partition net is set as a transfer space. A through hole communicating with the transfer space penetrates through the side wall of the housing. The transfer backwash assembly enters the transfer space through the through hole, and a sealing cover for blocking the through hole is movably connected to the housing. The backwash water cap plate is located at the bottom of the housing. The transfer backwash assembly has an independent return water cavity and a backwash cavity. The backwash cavity communicates with the upper half part of the transfer space, and the return water cavity communicates with the lower half part of the transfer space. The backwash cavity is communicated with a discharge pipe, and the return water cavity is communicated with a drain pipe.

[0009] By adopting the above technical solution, during normal filtration, the transfer backwash assembly is not located in the transfer space, that is, the upper and lower adjacent filter media layers are conducted to each other, and the sealing cover blocks the through hole to ensure the sealing performance. Wastewater enters the housing from the inlet pipe at the upper end of the housing. The wastewater is successively filtered and adsorbed by each filter media layer, and finally the purified water is discharged from the drain pipe.

[0010] When backwashing is required, the sealing cover is removed, and the transfer backwash assembly is horizontally moved into the transfer space through the through hole. The transfer backwash assembly divides the transfer space into two independent spaces. Among them, the backwash cavity communicates with the upper half part of the transfer space, and the return water cavity communicates with the lower half part of the transfer space.

[0011] The specific steps for backwashing the filter media layer located between the backwash water cap plate and the adjacent transfer backwash assembly are as follows: The backwash water cap plate sprays backwash water upward, and the backwash water entrains the impurities in the filter media layer upward to the lower half part of the transfer space, and finally discharges through the return water cavity and the drain pipe.

[0012] The specific steps for backwashing the filter media layer located between two adjacent transfer backwash assemblies are as follows: Backwash water is introduced into the discharge pipe of the lower transfer backwash assembly. The backwash water sprays upward through the backwash cavity of the transfer backwash assembly, and the backwash water entrains the impurities in the filter media layer upward. The backwash water carrying the impurities enters the return water cavity of the upper transfer backwash assembly, and finally discharges through the drain pipe.

[0013] The specific steps for backwashing the uppermost filter media layer are as follows: Backwash water is introduced into the discharge pipe of the transfer backwash assembly below the filter media layer. The backwash water sprays upward through the backwash cavity of the transfer backwash assembly, and the backwash water entrains the impurities in the filter media layer upward. Finally, the backwash water carrying the impurities is discharged through the sewage discharge pipe at the top of the housing.

[0014] In summary, by setting a backwash water cap plate and a plurality of movable transfer backwash components, it is possible to ensure the smoothness of normal filtration and adsorption, and to perform independent backwashing for each filter material layer. Since the moving path of the backwash water is short and the water pressure loss is small, the backwash water with better water pressure maintenance can more completely wash away the impurities. In addition, since the moving path of the backwash water is short, the probability of the impurities carried by the backwash water being intercepted by the filter material is greatly reduced, thereby greatly reducing the residual impurities in the filter material layer, further improving the backwash cleaning effect. Secondly, since each filter material layer is backwashed independently, it is not easy for the filter materials in adjacent filter material layers to mix with each other, so as to ensure the graded filtration effect. Finally, since each filter material layer is backwashed independently, the water pressure can be adjusted specifically according to the different filter material, specific gravity and particle size of each filter material layer, thereby further improving the backwash effect.

[0015] Optionally, the transfer backwash assembly includes a transfer shell, which is horizontally arranged and horizontally slidably arranged with the shell body through the through hole. A horizontally arranged partition is provided in the transfer shell, and the partition divides the inner cavity of the transfer shell into the backwash chamber and the return water chamber arranged upper and lower. The discharge pipe and the discharge pipe are respectively connected to the upper and lower halves of the side wall of the transfer shell; a plurality of backwash holes are penetrated on the upper surface of the transfer shell, and a plurality of return water holes are penetrated on the lower surface of the transfer shell.

[0016] Optionally, the upper partition net and the lower partition net are both arranged at an angle, and the lowest point of the lower partition net and the highest point of the upper partition net are both arranged away from the through hole; supporting edge strips are welded and fixed to the inner wall of the shell, and the supporting edge strips support the lowest point and the highest point of the lower partition net.

[0017] By adopting the above technical solution, by setting the upper partition net and the lower partition net, a transfer space with a larger volume can be defined between the filter material layers to facilitate the entry and removal of the transfer shell; and by the inclined setting of the upper and lower partition nets and the setting of the supporting edge strips, the situation in which the middle part of the lower partition net is excessively loaded and deformed downward, causing interference with the transfer shell, can be reduced.

[0018] Optionally, the inner wall cross-section of the shell is trapezoidal, the outer shape of the transfer shell is adapted to the inner wall cross-section of the shell, a sealing strip is fixed to the inner wall of the shell, and the sealing strip is used to fit the three side surfaces of the transfer shell; a first sealing embedment strip is fixed to the side wall of the transfer shell located outside the transfer space, and the edge of the opening of the through hole away from the transfer space is provided with a matching chamfer for matching with the first sealing embedment strip.

[0019] By adopting the above technical solution, when the transfer shell is installed in the transfer space, the three side walls of the transfer shell are respectively attached to the sealing strips to ensure the partition and sealing effect of the transfer shell on the transfer space. At the same time, the first sealing insertion strip of the transfer shell is attached to the chamfer of the through hole to seal the through hole, further improving the sealing performance to ensure the stable water pressure of the backwash water.

[0020] Optionally, it further includes a sealing reinforcement structure. A second sealing insertion strip is provided at the edge of the sealing cover, and the shape of the second sealing insertion strip is the same as that of the first sealing insertion strip. The sealing reinforcement structure includes a pressing block and a bolt. The bolt is horizontally arranged and is threadedly connected to the outer wall of the shell. One end of the pressing block is connected to the bolt, and the other end of the pressing block abuts against the sealing cover or the side wall of the transfer shell away from the transfer space.

[0021] By adopting the above technical solution, by setting the sealing reinforcement structure, when the bolt is tightened, the bolt drives the pressing block to move horizontally towards the shell direction. The pressing block abuts against the sealing cover or the side wall of the transfer shell away from the transfer space, so that the first sealing insertion strip or the second sealing insertion strip further compresses the chamfer of the mating part, thereby further improving the sealing performance to ensure the stable water pressure of the backwash water. Secondly, it can also improve the installation stability of the transfer shell and the sealing cover.

[0022] Optionally, it further includes a displacement driving structure. There is an active gap between the outer edge of the partition plate and the inner wall of the transfer shell. The outer edge of the partition plate and the inner wall of the transfer shell are connected by a rubber corrugated ring. The closed-loop contour of the rubber corrugated ring is trapezoidal. The partition plate and the rubber corrugated ring together divide the inner cavity of the transfer shell into the backwash cavity and the return water cavity. Two first connecting strips and two second connecting strips are fixed at the edge of the upper surface of the partition plate. The first connecting strip extends along the sliding direction of the transfer shell, and the second connecting strip is perpendicular to the first connecting strip. Both the first connecting strip and the second connecting strip have slots extending along their own length directions. Two first elastic pieces and second elastic pieces are fixed on the inner wall of the transfer shell. Both the first elastic piece and the second elastic piece have a wave segment and a bent segment. The end of the bent segment is slidably matched with the slot along the length direction of the slot. A rubber tube is fixed on the upper surface of the partition plate. The upper end of the rubber tube is fixed to the inner top wall of the transfer shell. The upper pipe orifice of the rubber tube is communicated with the backwash hole, and a flow channel hole is opened in the lower part of the rubber tube. The displacement driving structure includes a sliding rod, a driving block and a driven block. The sliding rod is slidably matched with the transfer shell horizontally. The driving block is a round block and is fixed at the end of the sliding rod. A plurality of driven blocks are provided. The driven blocks are fixed on the lower surface of the partition plate. The driven blocks are triangular. The driven blocks are arranged in a staggered manner along the sliding direction of the sliding rod. The two inclined surfaces of the driven block are respectively set as the first inclined surface and the second inclined surface. When the sliding rod advances, the outer peripheral surface of the driving block sequentially abuts against the first inclined surfaces of the driven blocks. When the sliding rod retreats, the outer peripheral surface of the driving block sequentially abuts against the second inclined surfaces of the driven blocks.

[0023] By adopting the above technical solution, the inner cavity of the transfer shell is divided into a backwashing cavity and a water return cavity by arranging a partition plate and a rubber corrugated ring together. The partition plate is movably connected to the transfer shell, so that the partition plate can displace relative to the transfer shell. The first elastic piece and the second elastic piece are respectively engaged with the clamping grooves of the first connecting strip and the second connecting strip, so that the partition plate is elastically connected to the transfer shell. After the partition plate displaces, it can be reset through this elastic connection, and the sliding fit of the clamping grooves greatly improves the displacement freedom of the partition plate.

[0024] During the backwashing process, backwashing water is introduced into the discharge pipe. The backwashing water enters the backwashing cavity, then enters the rubber tube through the flow holes of the rubber tube, and then sprays out upward through the backwashing holes. During this process, the push rod is pushed forward, and the outer peripheral surface of the driving block sequentially abuts against the first inclined surfaces of the driven blocks. During the process of abutting against a single first inclined surface, the driving block forces the driven block and the partition plate to make arc displacements in the horizontal plane (specifically, the partition plate displaces along the length directions of the first connecting strip and the second connecting strip respectively, and the two displacements are superimposed to form an arc displacement). After the abutting is completed, the partition plate and the driven block are elastically reset. Due to the staggered arrangement of the driven blocks, the arc displacement direction of the next driven block is opposite to that of the previous driven block, that is, the partition plate makes a reciprocating arc displacement. Similarly, when the push rod retracts, the outer peripheral surface of the driving block sequentially abuts against the second inclined surfaces of the driven blocks, and the partition plate also makes a reciprocating arc displacement and the direction is opposite.

[0025] During the reciprocating arc displacement of the partition plate, the lower end of the rubber tube will be driven by the partition plate to make a reciprocating arc displacement relative to the upper end of the rubber tube, and the state of the rubber tube continuously changes in an inclined manner, thereby changing the backwashing water spraying angle to increase the backwashing range and improve the backwashing effect. Moreover, the backwashing water spraying angle continuously changes, and its flushing angle for the filter material continuously changes, so that impurities can be flushed more completely, reducing the situation of impurity residue caused by backwashing dead angles. And, the adjacent two backwashing waters intersect with each other, and the filter material at the same position can be backwashed at different angles, thereby improving the flushing-down effect; finally, the upward movement path of the backwashing water in the filter material layer is more diverse, and the penetration conditions at different positions of the filter material layer are better, further improving the entrainment completeness of the backwashing water for impurities.

[0026] Optionally, along the advancing direction of the push rod, the included angle between each of the first inclined surfaces and the straight line segment of the driven block gradually increases; along the retracting direction of the push rod, the included angle between each of the second inclined surfaces and the straight line segment of the driven block gradually increases; along the advancing direction of the push rod, the shortest distance between each driven block and the virtual path line of the push rod gradually decreases.

[0027] By adopting the above technical solution, when the driving block abuts against the driven block, due to the different angles between the first inclined plane and the second inclined plane at each position and the different shortest distances between each driven block and the virtual path line of the slide bar, the partition will be changed along the length direction of the first connecting strip and the second connecting strip, respectively, thereby changing the arc displacement path. Different arc displacement paths will make the arc displacement path of the rubber tube different each time, so that the change range and change frequency of each backwash water injection angle are different, thereby further increasing the backwash range and improving the backwash effect. In addition, the backwash water injection angle has a higher continuous change frequency, and its flushing angle for the filter material changes continuously at a high frequency, so that impurities can be flushed more completely and the impurity residue caused by backwash dead corners can be reduced.

[0028] Optionally, the number of the transfer backwash components is two, and the number of the filter media layers is three. The filter media of the first filter media layer are anthracite and coarse quartz from top to bottom, wherein the anthracite particle size is 1-2 mm, and the coarse quartz particle size is 0.8-1.2 mm. The filter media of the second filter media layer is medium quartz, and the medium quartz particle size is 0.5-0.8 mm. The filter media of the third filter media layer is fine quartz, and the fine quartz particle size is 0.3-0.5 mm.

[0029] Optionally, the filter material surface of the filter material layer is coated with nano-SiO2.

[0030] By adopting the above technical solution, nano-SiO2 can improve the surface smoothness and pollution resistance of the filter material, and the hydrophilicity is enhanced, so that the amount of oil stains attached is reduced.

[0031] In summary, the present application includes at least one of the following beneficial technical effects: By setting a backwash water cap plate and a plurality of movable transfer backwash components, it is possible to ensure the smoothness of normal filtration and adsorption, and to perform independent backwashing for each filter material layer. Since the movement path of the backwash water is short and the water pressure loss is small, the backwash water with better water pressure maintenance can wash away impurities more completely. In addition, since the movement path of the backwash water is short, the probability of impurities carried by the backwash water being intercepted by the filter material is greatly reduced, thereby greatly reducing the residual impurities in the filter material layer and further improving the backwash cleaning effect. Secondly, since each filter material layer is backwashed independently, it is not easy for the filter materials in adjacent filter material layers to mix with each other, so as to ensure the graded filtration effect. Finally, since each filter material layer is backwashed independently, the water pressure can be adjusted specifically according to the different filter material, specific gravity and particle size of each filter material layer, so as to further improve the backwash effect; By setting up a displacement driving structure, during the reciprocating arc displacement of the partition plate, the lower end of the rubber tube will be driven by the partition plate to make a reciprocating arc displacement relative to the upper end of the rubber tube. The state of the rubber tube continuously changes in an inclined manner, thereby changing the backwashing water injection angle to increase the backwashing range and improve the backwashing effect. Moreover, the backwashing water injection angle continuously changes, and the flushing angle for the filter media also continuously changes, so that impurities can be flushed more completely, reducing the situation of impurity residue caused by backwashing dead angles. In addition, adjacent two backwashing waters cross each other, and the filter media at the same position can be backwashed at different angles, further improving the flushing effect. Finally, the upward movement path of the backwashing water in the filter media layer is more diverse, and the penetration situation at different positions of the filter media layer is better, further improving the entrainment completeness of the backwashing water for impurities. Description of the Drawings

[0032] Figure 1 It is a schematic diagram of each device of the overall system in Embodiment 1.

[0033] Figure 2 It is a cross-sectional view of the multi-media filter in Embodiment 1.

[0034] Figure 3 It is Figure 2 The partial enlarged view at A in

[0035] Figure 4 It is a cross-sectional view of the housing in Embodiment 1.

[0036] Figure 5 It is a schematic diagram of the sealing cover in Embodiment 1.

[0037] Figure 6 It is a schematic diagram of the transfer shell in Embodiment 1.

[0038] Figure 7 It is a cross-sectional view of the transfer shell in Embodiment 1.

[0039] Figure 8 It is a schematic diagram for showing the upper surface structure of the partition plate in Embodiment 2.

[0040] Figure 9 It is a cross-sectional view of the transfer shell in Embodiment 2.

[0041] Figure 10 It is Figure 9 The partial enlarged view at B in

[0042] Figure 11 It is a schematic diagram of the lower surface of the partition plate in Embodiment 2.

[0043] Figure 12 It is a schematic diagram of the lower surface of the partition plate in Embodiment 3.

[0044] Description of the reference numerals: 1, housing; 2, transfer housing; 10, filter media layer; 100, transfer space; 101, through hole; 1011, mating chamfer; 11, water inlet pipe; 12, sewage pipe; 13, drain pipe; 14, backwash water cap plate; 15, lower partition net; 16, upper partition net; 17, sealing cover; 171, connecting rope; 172, second sealing insertion strip; 18, bolt; 181, pressing block; 182, sealing strip; 19, supporting edge strip; 21, backwash chamber; 211, backwash hole; 22, return water chamber; 221, return water hole; 23, partition board; 231, rubber corrugated ring; 232, first connecting strip; 233, second connecting strip; 2331, clamping groove; 235, first elastic piece; 236, second elastic piece; 2361, wave segment; 2362, bending segment; 237, rubber tube; 2371, flow channel hole; 24, discharge pipe; 25, inlet pipe; 26, first sealing insertion strip; 27, perforation; 31, sliding rod; 32, driving block; 33, driven block; 331, first inclined surface; 332, second inclined surface. Detailed implementation manners

[0045] The following will further describe the present application in detail in conjunction with the attached Figure 1 - attached Figure 12 drawings.

[0046] Example 1. Example 1 discloses a water circulation treatment system for a hydroentangling production line. Refer to Figure 1 , the water circulation treatment system for a hydroentangling production line successively includes a drum filter, a flocculation device, a multi-media filter, an MBR membrane bioreactor, an ultrafiltration device, and a pH adjustment tank. The drum filter is used to remove fiber debris and large particle suspended matters. The flocculation device can adopt polyaluminum chloride coagulant, and the dosing amount is 50-100 mg / L. The multi-media filter will further remove suspended matters and adsorb part of the COD. The MBR membrane bioreactor is used to degrade dissolved CDD and synchronously remove nitrogen and phosphorus. The ultrafiltration device is used to intercept bacteria and colloids, so that the turbidity of the effluent is less than 0.5 NTU, and the COD is further reduced to below 30 mg / , so as to meet the reuse standard.

[0047] As Figure 2 , Figure 3 , Figure 4 shown ( Figure 2The solid arrows indicate the flow direction of the wastewater, and the dashed arrows indicate the flow direction of the backwash water. The multi-media filter includes a housing 1, multiple filter media layers 10, an upper partition net 16, a lower partition net 15, a backwash water cap plate 14, and a transfer backwash assembly. The housing 1 is vertical, and the inner wall cross-section of the housing 1 is trapezoidal. The upper end of the housing 1 is connected to a tee and a valve (not shown in the figure). Two of the pipe heads of the tee are the water inlet pipe 11 and the sewage discharge pipe 12 respectively. The lower end of the housing 1 is provided with a drain pipe 13. The filter media layers 10 are arranged vertically at intervals. The filter media layer 10 is set to three layers. The filter media of the first-layer filter media layer 10 is anthracite and coarse quartz from top to bottom. The particle size of the anthracite is 1 - 2 mm, and the particle size of the coarse quartz is 0.8 - 1.2 mm. The filter media of the second-layer filter media layer 10 is medium quartz, and the particle size of the medium quartz is 0.5 - 0.8 mm. The filter media of the third-layer filter media layer 10 is fine quartz, and the particle size of the fine quartz is 0.3 - 0.5 mm. In order to improve the surface smoothness and anti-pollution property of the filter media, nano-SiO2 can be coated on the surface of each filter media.

[0048] To ensure the position stability of each filter media layer 10, a supporting edge strip 19 is welded and fixed to the inner wall of the housing 1. The supporting edge strip 19 supports both sides of the lower partition net 15, so that the lower partition net 15 supports the lower surface of the filter media layer 10, while the upper partition net 16 fits against the upper surface of the filter media layer 10. The vertical gap between the adjacent lower partition net 15 and upper partition net 16 is set as the transfer space 100, that is, there is a transfer space 100 between adjacent two filter media layers 10, and a through hole 101 communicating with the transfer space 100 penetrates through the side wall of the housing 1.

[0049] Moreover, both the upper partition net 16 and the lower partition net 15 are inclined, and the lowest point of the lower partition net 15 and the highest point of the upper partition net 16 are both set away from the through hole 101.

[0050] The housing 1 is movably connected with a sealing cover 17 for blocking the through hole 101. Specifically, as Figure 3 、 Figure 5 shown, the sealing cover 17 is rectangular. The sealing cover 17 is fixed to the outside of the housing 1 through a connecting rope 171. A second sealing insertion strip 172 is fixed around the outer edge of the sealing cover 17. A mating chamfer 1011 for mating with the second sealing insertion strip 172 is provided at the edge of the hole of the through hole 101 away from the transfer space 100.

[0051] The housing 1 is also provided with a sealing strengthening structure. The sealing strengthening structure includes a pressing block 181 and a bolt 18. The bolt 18 is horizontally arranged and is threadedly connected to the outer wall of the housing 1. One end of the pressing block 181 is connected to the bolt 18. This connection can be a fixed connection or a penetrating connection. And the screw head of the bolt 18 presses on the surface of the pressing block 181. The other end of the pressing block 181 abuts against the side wall of the sealing cover 17 away from the transfer space 100.

[0052] The backwash water cap plate 14 is located at the bottom of the housing 1, and the water caps of the backwash water cap plate 14 are arranged upward. The backwash water cap plate 14 can be in a hollow shape to facilitate the downward passage of the purified water.

[0053] During normal filtration, the transfer backwash assembly is not located in the transfer space 100, that is, the adjacent upper and lower filter media layers 10 are in communication. The sealing cover 17 seals the through hole 101 to ensure the sealing performance. Then, the bolt 18 is tightened, and the bolt 18 drives the pressing block 181 to move horizontally towards the housing 1. The pressing block 181 abuts against the side wall of the sealing cover 17 away from the transfer space 100, so that the second sealing insertion strip 172 further tightly fits with the chamfer 1011 to improve the installation stability of the sealing cover 17. Then, the wastewater enters the housing 1 from the water inlet pipe 11 at the upper end of the housing 1. The wastewater is filtered and adsorbed by each filter media layer 10 in sequence, and finally the purified water is discharged from the drain pipe 13.

[0054] There are two transfer backwash assemblies, and the transfer backwash assemblies can enter the transfer space 100 through the through hole 101. Specifically, as Figure 4 、 Figure 6 、 Figure 7 shown, the transfer backwash assembly includes a transfer housing 2, a drain pipe 25 and a discharge pipe 24. The transfer housing 2 is horizontally arranged, and the outer shape of the transfer housing 2 is adapted to the inner wall cross-section of the housing 1. The transfer housing 2 is horizontally slidably arranged with the housing 1 through the through hole 101. A horizontally arranged partition 23 is fixed in the transfer housing 2. The partition 23 divides the inner cavity of the transfer housing 2 into an upper backwash cavity 21 and a lower return water cavity 22. The backwash cavity 21 and the return water cavity 22 are independent of each other. A plurality of backwash holes 211 penetrate through the upper surface of the transfer housing 2, and a plurality of return water holes 221 penetrate through the lower surface of the transfer housing 2, so that the backwash cavity 21 is communicated with the upper half part of the transfer space 100, and the return water cavity 22 is communicated with the lower half part of the transfer space 100.

[0055] The drain pipe 25 and the discharge pipe 24 are respectively connected to the upper half part and the lower half part of the side wall of the transfer housing 2, and the drain pipe 25 and the discharge pipe 24 are arranged in a staggered manner. The drain pipe 25 is communicated with the backwash cavity 21, and the discharge pipe 24 is communicated with the return water cavity 22.

[0056] In order to improve the sealing performance of the transfer housing 2 in the housing 1, the following settings are also made. As Figure 3 、 Figure 4 shown, a sealing strip 182 is fixed on the inner wall of the housing 1, and a circle of first sealing insertion strips 26 is fixed on the side wall of the transfer housing 2 located outside the transfer space 100. The shape of the first sealing insertion strip 26 is the same as that of the second sealing insertion strip 172.

[0057] When backwashing is required, loosen the bolt 18 so that the pressure block 181 avoids the sealing cover 17, remove the sealing cover 17, and install the transfer shell 2 into the transfer space 100 through the through hole 101. At this time, the three side walls of the transfer shell 2 are respectively fitted with the sealing strip 182 to ensure the separation and sealing effect of the transfer shell 2 on the transfer space 100. At the same time, the first sealing embedding strip 26 of the transfer shell 2 is fitted with the matching chamfer 1011 of the through hole 101 to seal the through hole 101, and then tighten the bolt 18. The bolt 18 drives the pressure block 181 to move horizontally toward the shell 1, and the pressure block 181 abuts against the side wall of the transfer shell 2 away from the transfer space 100, so that the first sealing embedding strip 26 is further pressed against the matching chamfer 1011.

[0058] After the transfer shell 2 is installed, the backwash chamber 21 of the transfer shell 2 is connected to the upper half of the transfer space 100 , and the return water chamber 22 is connected to the lower half of the transfer space 100 .

[0059] The specific steps for backwashing the third filter layer 10 are as follows: the backwash water cap plate 14 sprays backwash water upward, and the backwash water carries the impurities in the filter layer 10 upward to the lower half of the transfer space 100, and is finally discharged through the return water chamber 22 and the discharge pipe 24.

[0060] The specific steps for backwashing the filter layer 10 (the second filter layer 10) located between two adjacent transfer backwash components are as follows: backwash water is introduced into the discharge pipe 25 of the transfer shell 2 located below, and the backwash water is sprayed upward through the backwash chamber 21 and the backwash hole 211 of the transfer shell 2. The backwash water carries the impurities in the filter layer 10 upward, and the backwash water carrying the impurities enters the return water chamber 22 of the transfer shell 2 located above, and is finally discharged through the discharge pipe 24.

[0061] The specific steps for backwashing the filter layer 10 (first layer) located at the top are as follows: backwash water is introduced into the discharge pipe 25 of the transfer shell 2 below the filter layer 10, and the backwash water is sprayed upward through the backwash chamber 21 and the backwash hole 211 of the transfer shell 2. The backwash water carries the impurities in the filter layer 10 upward, and finally the backwash water carrying the impurities is discharged through the drain pipe 12 at the top of the shell 1.

[0062] In this way, by setting up the backwash water cap plate 14 and a plurality of movable transfer backwash components, it is possible to ensure the smoothness of normal filtration and adsorption, and to perform independent backwashing for each filter material layer 10. Since the movement path of the backwash water is shorter and the water pressure loss is smaller, the backwash water with better water pressure maintenance can more completely wash away impurities.

[0063] Furthermore, since the movement path of the backwash water is shorter, the probability of impurities carried by the backwash water being intercepted by the filter material is greatly reduced, thereby greatly reducing the residual impurities in the filter material layer 10 and further improving the backwash cleaning effect.

[0064] Secondly, since each filter material layer 10 is backwashed independently, it is not easy for filter materials in adjacent filter material layers 10 to be mixed with each other, thereby ensuring the graded filtering effect.

[0065] Finally, since each filter material layer 10 is backwashed independently, the water pressure can be adjusted specifically according to the different filter material, specific gravity and particle size of each filter material layer 10, thereby further improving the backwashing effect.

[0066] Embodiment 2, embodiment 2 is different from embodiment 1 in that, Figure 8 , Figure 9 , Figure 10 As shown, there is a movable gap between the outer edge of the partition 23 and the inner wall of the transfer shell 2, and the outer edge of the partition 23 is connected to the inner wall of the transfer shell 2 through a rubber corrugated ring 231. The closed loop profile of the rubber corrugated ring 231 is trapezoidal. The partition 23 and the rubber corrugated ring 231 together divide the inner cavity of the transfer shell 2 into a backwash chamber 21 and a return water chamber 22. The rubber corrugated ring not only plays a role of separation and sealing, but also allows the partition 23 to be displaced relative to the transfer shell 2.

[0067] Two first connecting strips 232 and two second connecting strips 233 are fixed at the edge of the upper surface of the partition 23, wherein the first connecting strip 232 extends along the sliding direction of the intermediate transfer shell 2, and the second connecting strip 233 is perpendicular to the first connecting strip 232, and the first connecting strip 232 and the second connecting strip 233 both have a slot 2331 extending along their own length direction; two first elastic sheets 235 and two second elastic sheets 236 are fixed to the inner wall of the intermediate transfer shell 2, the first elastic sheet 235 is arranged corresponding to the first connecting strip 232, and the second elastic sheet 236 is arranged corresponding to the second connecting strip 233, and the first elastic sheet 235 and the second elastic sheet 236 both have a wave section 2361 and a bending section 2362, the end of the wave section 2361 is fixed to the inner wall of the intermediate transfer shell 2, and the end of the bending section 2362 is slidably matched with the slot 2331 along the length direction of the slot 2331.

[0068] The wave section 2361 has the characteristic of easy elastic deformation to improve the elasticity of the first spring piece 235 and the second spring piece 236 along their own length direction. The partition 23 is elastically connected to the transfer shell 2. After the partition 23 is displaced, it can be reset through the elastic connection, and the bending section 2362 plays a connecting role to ensure that the partition 23 has a larger displacement freedom in the horizontal plane.

[0069] A rubber tube 237 is fixed to the upper surface of the partition 23, the upper end of the rubber tube 237 is fixed to the inner top wall of the intermediate shell 2, the upper pipe mouth of the rubber tube 237 is connected to the backwash hole 211, and a flow channel hole 2371 is opened at the lower part of the rubber tube 237. When the partition 23 is in the center position of the intermediate shell 2, the rubber tube 237 is in a vertical state.

[0070] The transfer backwashing assembly further includes a displacement driving structure, such as Figure 9 , Figure 11 As shown, the displacement driving structure includes a sliding rod 31, a driving block 32 and a driven block 33. The sliding rod 31 is in horizontal sliding fit with the transfer housing 2. Specifically, a through hole 27 is formed in the side wall of the transfer housing 2 corresponding to the return water chamber 22, and the sliding rod 31 is in sliding fit with the through hole 27. And, in order to improve the linearity of the sliding of the sliding rod 31, in other embodiments, a sliding tube may be fixed to the transfer housing 2, the sliding tube is coaxial with the through hole 27, and the sliding rod 31 passes through the sliding tube; the driving source of the sliding rod 31 may be manual pushing or an electric push rod is installed on the outer wall of the transfer housing 2 to push in an electric manner.

[0071] The driving block 32 is a round block, the driving block 32 is fixed to the end of the sliding rod 31, and a plurality of driven blocks 33 are provided. The driven blocks 33 are fixed to the lower surface of the partition plate 23. In this embodiment, the driven block 33 is an isosceles triangle, and the driven blocks 33 are arranged in a staggered manner along the sliding direction of the sliding rod 31. The two inclined surfaces of the driven block 33 are respectively set as a first inclined surface 331 and a second inclined surface 332.

[0072] During the backwashing process, backwashing water is introduced into the discharge pipe 25. The backwashing water enters the backwashing chamber 21, then enters the rubber tube 237 through the flow passage hole 2371 of the rubber tube 237, and then sprays upward through the backwashing hole 211. During this process, the sliding rod 31 is pushed forward, and the outer peripheral surface of the driving block 32 sequentially abuts against the first inclined surfaces 331 of the driven blocks 33. During the abutment against a single first inclined surface 331, the driving block 32 forces the driven block 33 and the partition plate 23 to make an arc displacement in the horizontal plane (specifically, the partition plate 23 displaces along the length directions of the first connecting strip 232 and the second connecting strip 233 respectively, and the two displacements are superimposed to form an arc displacement). After the abutment, the partition plate 23 and the driven block 33 are elastically reset. Due to the staggered arrangement of the driven blocks 33, the arc displacement direction of the next driven block 33 is opposite to that of the previous driven block 33, that is, the partition plate 23 makes a reciprocating arc displacement. Similarly, when the sliding rod 31 retracts, the outer peripheral surface of the driving block 32 sequentially abuts against the second inclined surfaces 332 of the driven blocks 33, and the partition plate 23 also makes a reciprocating arc displacement and the direction is opposite.

[0073] During the reciprocating arc displacement of the partition plate 23, the partition plate 23 will drive the lower end of the rubber tube 237 to make a reciprocating arc displacement relative to the upper end of the rubber tube 237, and the state of the rubber tube 237 continuously changes in inclination, so as to change the backwashing water spraying angle, improve the backwashing range and improve the backwashing effect.

[0074] Moreover, the backwashing water spraying angle continuously changes, and its flushing angle for the filter material continuously changes, so that impurities can be flushed more completely, reducing the situation of impurity residue caused by backwashing dead angles. And, adjacent two backwashing waters are relatively easy to cross each other, and the filter material at the same position can be backwashed at different angles, thereby improving the flushing effect.

[0075] Finally, the upward movement path of the backwashing water in the filter media layer 10 is more diverse, and the penetration conditions at different positions of the filter media layer 10 are better, further improving the entrainment completeness of the backwashing water for impurities.

[0076] Embodiment 3. The difference between Embodiment 3 and Embodiment 2 lies in defining the shape and position of the driven block 33. As Figure 12 shown, along the advancing direction of the sliding rod 31, the included angle between each first inclined surface 331 and the straight line segment of the driven block 33 gradually increases; along the retracting direction of the sliding rod 31, the included angle between each second inclined surface 332 and the straight line segment of the driven block 33 gradually increases; along the advancing direction of the sliding rod 31, the shortest distance between each driven block 33 and the virtual path line of the sliding rod 31 gradually decreases.

[0077] When the driving block 32 abuts against the driven block 33, due to the different included angles of the first inclined surfaces 331 and the second inclined surfaces 332 at each position, and the different shortest distances between each driven block 33 and the virtual path line of the sliding rod 31, the displacement amounts of the partition plate 23 along the length directions of the first connecting strip 232 and the second connecting strip 233 will be changed, thereby changing the arc displacement path. And different arc displacement paths will cause the arc displacement path of the rubber tube 237 to be different each time, resulting in different variation ranges and variation frequencies of the injection angle of the backwashing water each time, thereby further increasing the backwashing range and improving the backwashing effect.

[0078] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A water circulation treatment system for a hydroentangling production line, characterized in that: It successively includes a rotary drum filter, a flocculation device, a multi-media filter, an MBR membrane bioreactor, an ultrafiltration device and a pH adjustment tank. The multi-media filter includes a housing (1), a plurality of filter media layers (10), an upper separation net (16), a lower separation net (15), a backwash water cap plate (14) and a transfer backwash assembly. The upper end of the housing (1) is provided with a water inlet pipe (11) and a sewage discharge pipe (12), and the lower end of the housing (1) is provided with a drain pipe (13). The filter media layers (10) are arranged at intervals vertically. The upper separation net (16) is attached to the upper surface of the filter media layer (10), and the lower separation net (15) supports the lower surface of the filter media layer (10). The vertical gap between the adjacent lower separation net (15) and the upper separation net (16) is set as a transfer space (100). A through hole (101) communicating with the transfer space (100) penetrates through the side wall of the housing (1). The transfer backwash assembly enters the transfer space (100) through the through hole (101). The housing (1) is movably connected with a sealing cover (17) for blocking the through hole (101). The backwash water cap plate (14) is located at the bottom of the housing (1). The transfer backwash assembly has an independent backwash chamber (21) and a return water chamber (22). The backwash chamber (21) communicates with the upper half part of the transfer space (100), and the return water chamber (22) communicates with the lower half part of the transfer space (100). The backwash chamber (21) is communicated with a discharge pipe (25), and the return water chamber (22) is communicated with a drain pipe (24).

2. The water circulation treatment system for a hydroentangling production line according to claim 1, wherein: The transfer backwash assembly includes a transfer housing (2). The transfer housing (2) is horizontally arranged. The transfer housing (2) is horizontally slidably arranged with the housing (1) through the through hole (101). A horizontally arranged partition board (23) is arranged in the transfer housing (2). The partition board (23) divides the inner cavity of the transfer housing (2) into the upper and lower arranged backwash chamber (21) and the return water chamber (22). The discharge pipe (25) and the drain pipe (24) are respectively connected to the upper half part and the lower half part of the side wall of the transfer housing (2). A plurality of backwash holes (211) penetrate through the upper surface of the transfer housing (2), and a plurality of return water holes (221) penetrate through the lower surface of the transfer housing (2).

3. The water circulation treatment system for a hydroentangling production line according to claim 2, characterized in that: Both the upper separation net (16) and the lower separation net (15) are inclined. The lowest point of the lower separation net (15) and the highest point of the upper separation net (16) are both arranged away from the through hole (101). A supporting edge strip (19) is welded and fixed on the inner wall of the housing (1). The supporting edge strip (19) supports the lowest point and the highest point of the lower separation net (15).

4. The water circulation treatment system for a hydroentangling production line according to claim 2, characterized in that: The inner wall cross-section of the housing (1) is trapezoidal, the outer shape of the transfer housing (2) is adapted to the inner wall cross-section of the housing (1), and a sealing strip (182) is fixed to the inner wall of the housing (1) for fitting against three sides of the transfer housing (2); a first sealing and embedding strip (26) is fixed to the side wall of the transfer housing (2) located outside the transfer space (100), and a mating chamfer (1011) for cooperating with the first sealing and embedding strip (26) is provided at the edge of the hole opening of the through hole (101) remote from the transfer space (100).

5. The water circulation treatment system for a hydroentangling production line according to claim 4, characterized in that: It further includes a sealing strengthening structure. A second sealing and embedding strip (172) is provided at the edge of the sealing cover (17), and the shape of the second sealing and embedding strip (172) is the same as that of the first sealing and embedding strip (26); the sealing strengthening structure includes a pressing block (181) and a bolt (18). The bolt (18) is horizontally arranged and is threadedly connected to the outer wall of the housing (1). One end of the pressing block (181) is connected to the bolt (18), and the other end of the pressing block (181) abuts against the sealing cover (17) or the side wall of the transfer housing (2) remote from the transfer space (100).

6. The water circulation treatment system for a hydroentangling production line according to claim 2, characterized in that: It further includes a displacement driving structure. There is an active gap between the outer edge of the partition plate (23) and the inner wall of the transfer shell (2). The outer edge of the partition plate (23) and the inner wall of the transfer shell (2) are connected through a rubber corrugated ring (231). The closed-loop contour of the rubber corrugated ring (231) is trapezoidal. The partition plate (23) and the rubber corrugated ring (231) together divide the inner cavity of the transfer shell (2) into the backwashing cavity (21) and the return water cavity (22). At the edge of the upper surface of the partition plate (23), two first connecting bars (232) and two second connecting bars (233) are fixed. Among them, the first connecting bar (232) extends along the sliding direction of the transfer shell (2), the second connecting bar (233) is perpendicular to the first connecting bar (232), and both the first connecting bar (232) and the second connecting bar (233) have a card slot (2331) extending along their own length directions. Two first elastic pieces (235) and a second elastic piece (236) are fixed on the inner wall of the transfer shell (2). Both the first elastic piece (235) and the second elastic piece (236) have a wave segment (2361) and a bending segment (2362). The end of the bending segment (2362) is in sliding fit with the card slot (2331) along the length direction of the card slot (2331). A rubber tube (237) is fixed on the upper surface of the partition plate (23). The upper end of the rubber tube (237) is fixed to the inner top wall of the transfer shell (2). The upper pipe orifice of the rubber tube (237) is communicated with the backwashing hole (211). A flow passage hole (2371) is opened in the lower part of the rubber tube (237). The displacement driving structure includes a sliding rod (31), a driving block (32), and a driven block (33). The sliding rod (31) is in horizontal sliding fit with the transfer shell (2). The driving block (32) is a round block, and the driving block (32) is fixed to the end of the sliding rod (31). A plurality of driven blocks (33) are provided. The driven blocks (33) are fixed to the lower surface of the partition plate (23). The driven blocks (33) are triangular. The driven blocks (33) are arranged in a staggered manner along the sliding direction of the sliding rod (31). The two inclined surfaces of the driven block (33) are respectively set as a first inclined surface (331) and a second inclined surface (332). When the sliding rod (31) advances, the outer peripheral surface of the driving block (32) sequentially abuts against the first inclined surfaces (331) of the driven blocks (33). When the sliding rod (31) retreats, the outer peripheral surface of the driving block (32) sequentially abuts against the second inclined surfaces (332) of the driven blocks (33).

7. The water circulation treatment system for a hydroentangling production line according to claim 6, characterized in that: Along the advancing direction of the sliding rod (31), the included angle between each of the first inclined surfaces (331) and the straight line segment of the driven block (33) gradually increases; along the retreating direction of the sliding rod (31), the included angle between each of the second inclined surfaces (332) and the straight line segment of the driven block (33) gradually increases; along the advancing direction of the sliding rod (31), the shortest distance between each driven block (33) and the virtual path line of the sliding rod (31) gradually decreases.

8. The water circulation treatment system for a hydroentangling production line according to claim 1, characterized in that: There are two transfer backwashing components, and the filter media layer (10) is divided into three layers. The filter media of the first layer of the filter media layer (10) from top to bottom are anthracite and coarse quartz in sequence, where the particle size of the anthracite is 1 - 2 mm, and the particle size of the coarse quartz is 0.8 - 1.2 mm. The filter media of the second layer of the filter media layer (10) is medium quartz, and the particle size of the medium quartz is 0.5 - 0.8 mm; the filter media of the third layer of the filter media layer (10) is fine quartz, and the particle size of the fine quartz is 0.3 - 0.5 mm.

9. The water circulation treatment system for a hydroentangling production line according to claim 1, characterized in that: The surface of the filter media of the filter media layer (10) is coated with nano - SiO₂.

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