A filter material layered support device for sewage treatment multi-stage filtration

Abstract

The utility model provides a kind of filter material layered support device of sewage treatment multistage filtration belongs to support device technical field, the filter material layered support device of sewage treatment multistage filtration includes filter cylinder body and support frame body, support frame body is arranged in the inside of filter cylinder body, wherein, support frame body includes central support column and multilayer distribution plate, central support column extends along vertical direction, distribution plate is spaced distribution along the axial direction of central support column, each layer distribution plate is annular structure and is around the geometric center of central support column setting, the inner edge of distribution plate is fixedly connected with the outer peripheral surface of central support column, the outer edge of distribution plate and the inner wall surface of filter cylinder body keep pre-set gap, multiple water-permeable holes are set up on distribution plate, water-permeable hole is array distribution along radial direction, independent filter material containing cavity is formed between two adjacent layers distribution plate, solve the uneven water flow, the structural defect problem of poor drainage caused by split stacking or complex baffle of existing multistage filtration device.

Description

Technical Field

[0001] This utility model belongs to the field of support device technology, specifically, it relates to a layered support device for filter media in multi-stage filtration for sewage treatment. Background Technology

[0002] Wastewater treatment is a crucial aspect of environmental protection. Multistage filtration technology is a widely used method in wastewater treatment. It involves layering filter media of different particle sizes to progressively remove suspended solids and impurities of varying sizes from wastewater. Existing multistage filtration systems typically employ multiple independent filter cylinders connected in series, each filled with a single particle size of filter media. Wastewater flows through each cylinder sequentially to complete the multistage filtration. This series-cascade structure suffers from drawbacks such as large footprint, complex piping connections, high installation costs, and high system resistance. Another common approach is to use multiple partitions within a single cylinder to divide it into multiple independent filter chambers, each filled with a different particle size of filter media. However, this partition-type structure presents challenges such as difficult partition installation, poor sealing, easy mixing of filter media layers under water flow impact, and a complex drainage system. In addition to these issues, some technical solutions use perforated plates as filter media supports. However, perforated plates often lack sufficient strength and are prone to deformation or even breakage when bearing the weight of the filter media. Furthermore, unreasonable pore size design of perforated plates leads to uneven water flow distribution, with some areas experiencing excessive filtration load while others are insufficiently filtered. Moreover, existing drainage systems typically employ side wall openings or multi-point drainage at the bottom, which can easily cause inconsistent filtration effects across different filter media layers. The complex layout of drainage pipes also increases the difficulty of system maintenance. In terms of filter media replacement and cleaning, existing technologies often require disassembling a large number of connectors or lifting the entire cylinder, which is cumbersome and time-consuming. These shortcomings of existing technologies restrict the widespread application of multi-stage filtration systems for wastewater treatment. There is an urgent need for a filter media layer support device that is simple in structure, easy to install, highly efficient, and easy to maintain. Utility Model Content

[0003] In view of this, the present invention provides a layered support device for filter media in multi-stage filtration for sewage treatment, which solves the structural defects of existing multi-stage filtration devices caused by separate stacking or complex partitions, resulting in uneven water flow and poor drainage.

[0004] This utility model is implemented as follows:

[0005] This utility model provides a layered support device for multi-stage filtration in wastewater treatment, comprising a filter cylinder and a support frame. The support frame is disposed inside the filter cylinder, and includes a central support column and multiple distribution plates. The central support column extends vertically, and the distribution plates are spaced apart along the axial direction of the central support column. Each layer of distribution plate has a ring structure and is arranged around the geometric center of the central support column. The inner edge of the distribution plate is fixedly connected to the outer circumferential surface of the central support column, and a preset gap is maintained between the outer edge of the distribution plate and the inner wall surface of the filter cylinder. Multiple water-permeable holes are provided on the distribution plates, and the water-permeable holes are arranged in an array along the radial direction. An independent filter media receiving cavity is formed between two adjacent layers of distribution plates. The central support column is a hollow structure, and multiple drainage holes are provided on the side wall of the central support column, and the drainage holes are connected to the receiving cavities of each layer of filter media.

[0006] The technical advantages of the multi-stage filtration filter media layered support device for sewage treatment provided by this utility model are as follows: By setting a support frame composed of a central support column and multiple distribution plates, effective layered support for filter media of different particle sizes is achieved. The annular structure of the distribution plates ensures uniform distribution of the filter media. The preset gap between the outer edge of the distribution plate and the inner wall of the filter cylinder avoids the accumulation of filter media at the edge of the cylinder. The array distribution of permeable holes ensures uniform infiltration of sewage. The hollow structure of the central support column, together with the drainage holes, forms a centralized drainage channel, which improves the filtration efficiency. The independent filter media receiving cavity formed by two adjacent layers of distribution plates realizes the layered arrangement of multi-stage filtration. The overall structure is simple and reasonable and easy to install and maintain.

[0007] Based on the above technical solution, the filter media layer support device for multi-stage filtration in wastewater treatment of this utility model can be further improved as follows:

[0008] The distribution plate has an annular protrusion structure on its upper surface, which protrudes upward from the upper surface of the distribution plate. The height of the annular protrusion structure is 2 to 4 times the thickness of the distribution plate.

[0009] The beneficial effects of adopting the above-mentioned improved scheme are as follows: the annular protrusion structure on the upper surface of the distribution plate plays a limiting role, preventing the upper filter media from flowing into the lower filter media receiving cavity under the impact of water flow. The height of the annular protrusion structure is set to 2 to 4 times the thickness of the distribution plate, which not only ensures sufficient limiting effect, but also does not excessively occupy the effective volume of the filter media receiving cavity. The annular protrusion structure also enhances the overall rigidity of the distribution plate, making the distribution plate less prone to deformation when bearing the weight of the filter media.

[0010] Furthermore, the permeable holes are circular or elliptical, and the diameter of the permeable holes gradually increases from the inside to the outside along the radial direction of the distribution plate. The ratio of the diameter of the innermost permeable hole to the diameter of the outermost permeable hole is 1:2 to 1:3.

[0011] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the circular or elliptical shape of the permeable holes reduces the resistance when water flows through; the design of the permeable hole diameter gradually increasing from the inside to the outside in the radial direction conforms to the flow law of water on the distribution plate; the smaller diameter of the inner ring improves the interception capacity of fine particles; the larger diameter of the outer ring increases the overall water permeability; and the setting of the ratio of the innermost and outermost permeable hole diameters of 1:2 to 1:3 optimizes the water flow distribution and avoids uneven filtration caused by excessive or insufficient local water flow.

[0012] Furthermore, the outer circumferential surface of the central support column is provided with multiple longitudinal reinforcing ribs, which extend along the axial direction of the central support column. The cross-section of the longitudinal reinforcing ribs is triangular or trapezoidal, and the bottom edge of the longitudinal reinforcing ribs is fixedly connected to the outer circumferential surface of the central support column.

[0013] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the longitudinal stiffeners on the outer periphery of the central support column significantly improve the bending strength and torsional strength of the central support column, so that the central support column remains stable when bearing the total weight of the multi-layer distribution plate and filter media. The arrangement of the longitudinal stiffeners extending along the axial direction is consistent with the main load direction borne by the central support column. The triangular or trapezoidal cross-section of the stiffeners reduces the amount of material used while ensuring strength. The fixed connection between the stiffeners and the outer periphery of the central support column ensures the reliability of the overall structure.

[0014] Furthermore, the outer edge of the distribution plate is provided with a downwardly extending annular baffle. The distance between the lower end face of the annular baffle and the upper surface of the next layer of distribution plate is 1 / 3 to 1 / 2 of the height of the filter material receiving cavity. The thickness of the annular baffle is less than the thickness of the distribution plate.

[0015] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the annular baffle on the outer edge of the distribution plate forms a circumferential constraint on the filter media, preventing the filter media from being lost from the gap between the distribution plate and the inner wall of the cylinder under the action of water flow. The distance between the lower end face of the annular baffle and the upper surface of the lower distribution plate is set to one-third to one-half of the height of the filter media receiving cavity, which not only ensures the effective interception of the filter media, but also leaves enough space for the water to flow downward from the gap. The design that the thickness of the annular baffle is less than the thickness of the distribution plate reduces material consumption and lightens the overall weight.

[0016] Furthermore, a flow guide cone is provided inside the central support column, with the cone apex facing the bottom of the central support column. An annular flow channel is formed between the sidewall of the flow guide cone and the inner wall of the central support column, and the drain hole is connected to the annular flow channel.

[0017] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the guide cone inside the central support column guides the filtered water flow to converge downwards along the cone surface, avoiding turbulent flow of water inside the hollow support column. The setting of the guide cone apex facing the bottom ensures a smooth transition of water flow, reducing water flow impact and energy loss. The annular flow channel between the side wall of the guide cone and the inner wall of the central support column provides a smooth downward channel for water flow. The connection between the drain hole and the annular flow channel ensures that the filtered water from each layer can smoothly enter the interior of the central support column for centralized discharge.

[0018] Furthermore, the distribution plate and the central support column are connected by welding or bolt assembly. When bolt assembly is used, the inner edge of the distribution plate is provided with mounting holes, and the corresponding position on the outer circumferential surface of the central support column is provided with threaded holes. The bolt passes through the mounting holes and is screwed into the threaded holes.

[0019] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the distribution plate and the central support column are provided with two connection methods: welding or bolt assembly. Welded connection has the advantages of high connection strength and compact structure, while bolt assembly connection is convenient for on-site installation and subsequent maintenance and replacement. The mounting holes on the inner edge of the distribution plate match the threaded holes on the outer circumference of the central support column. The connection method of bolts passing through the mounting holes and being screwed into the threaded holes ensures the reliability of the connection. This selectable connection method improves the adaptability and maintenance convenience of the device.

[0020] Furthermore, the support frame is made of stainless steel or polypropylene, and the filter cylinder is made of fiberglass or carbon steel.

[0021] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: when the support frame is made of stainless steel, it has excellent corrosion resistance and mechanical strength, making it suitable for highly corrosive wastewater treatment environments; when it is made of polypropylene, it has the advantages of light weight and low cost, making it suitable for general wastewater treatment applications; when the filter cylinder is made of fiberglass, it has both strength and corrosion resistance; when it is made of carbon steel, it has low cost and high strength. Different material combinations meet different working conditions and economic requirements, and all materials are well-known materials that are easy to purchase and process.

[0022] Furthermore, the lower surface of the distribution plate is provided with a plurality of reinforcing ribs, which are arranged along the radial direction of the distribution plate, and the two ends of the reinforcing ribs are respectively connected to the outer peripheral surface of the central support column and the inner side of the outer edge of the distribution plate.

[0023] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the multiple reinforcing ribs on the lower surface of the distribution plate further enhance the load-bearing capacity of the distribution plate. The reinforcing ribs are arranged in the radial direction in the same direction as the radial bending moment that the distribution plate mainly bears. The two ends of the reinforcing ribs are connected to the outer periphery of the central support column and the inner side of the outer edge of the distribution plate, respectively, forming a stable support structure. This allows the distribution plate to remain flat when bearing the weight of the upper filter media and the water flow pressure. The setting of the reinforcing ribs also increases the contact area at the connection between the distribution plate and the central support column, improving the connection strength and overall stability.

[0024] Furthermore, a conical base is provided at the bottom of the filter cylinder, with the cone apex facing downwards. The bottom end of the central support column is fixedly connected to the cone apex of the conical base. A drain outlet is provided at the lowest point of the conical base, and the diameter of the drain outlet is 1 / 10 to 1 / 5 of the inner diameter of the filter cylinder.

[0025] The beneficial effects of adopting the above-mentioned improved scheme are as follows: the conical base at the bottom of the filter cylinder allows the deposited sludge and impurities to naturally collect towards the top of the cone. The downward-facing design of the cone top, combined with gravity, enables the automatic accumulation of sludge. The bottom end of the central support column is fixed at the top of the conical base, which ensures a reliable connection between the support frame and the cylinder. The drain port at the lowest point of the conical base facilitates the periodic discharge of deposited sludge. The diameter of the drain port is set to one-tenth to one-fifth of the inner diameter of the filter cylinder, which ensures smooth drainage and avoids the opening being too large, thus affecting the strength of the bottom of the cylinder. The overall structure is easy to maintain and clean.

[0026] Compared with existing technologies, the beneficial effects of the multi-stage filter media layered support device for sewage treatment provided by this utility model are as follows: This utility model effectively solves the technical problem of layered support of filter media in existing technologies by setting a support frame structure that combines a central support column with multiple layers of distribution plates. The central support column, as the main load-bearing component of the entire support frame, works in conjunction with the multiple layers of annular distribution plates to achieve precise layering of filter media with different particle sizes. The annular structure of each layer of distribution plates ensures the uniform distribution of filter media within the filter cylinder. The array arrangement and pore size gradient design of the permeable holes on the distribution plates allow sewage to permeate evenly through each layer of filter media, achieving a sufficient filtration effect. The hollow structure of the central support column, combined with the drainage holes, forms a centralized drainage system. This system avoids the complex piping problems caused by independent drainage of each layer in traditional multi-cylinder structures. The independent filter media receiving cavities formed between adjacent distribution plates effectively prevent the mixing of filter media of different particle sizes, ensuring the grading effect of multi-stage filtration. The combination design of the preset gap and annular baffle on the outer edge of the distribution plate ensures smooth water flow and prevents filter media loss. The setting of the guide cone optimizes the water flow state inside the central support column, reducing water flow resistance and energy loss. The overall structure is simple and reasonable, easy to install and maintain, and occupies little space. Compared with existing technologies, it has significant advantages such as compact structure, high filtration efficiency, stable operation, simple maintenance, and long service life. It is suitable for multi-stage filtration processes in various sewage treatment systems. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is an example diagram of a layered support device for multi-stage filtration in wastewater treatment.

[0029] Figure 2 A top view of a multi-stage filter media layer support device for wastewater treatment;

[0030] The attached diagram lists the components represented by each number as follows:

[0031] 10. Filter cylinder; 20. Support frame; 21. Central support column; 21. Drainage hole; 22. Distribution plate. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0033] like Figure 1 , Figure 2 The diagram shown is an example of a multi-stage filter media layered support device for wastewater treatment provided by this utility model. It includes a filter cylinder 10 and a support frame 20. The support frame 20 is disposed inside the filter cylinder 10. The support frame 20 includes a central support column 21 and multiple distribution plates 22. The central support column 21 extends vertically, and the distribution plates 22 are spaced apart along the axial direction of the central support column 21. Each layer of distribution plate 22 has a ring structure and is arranged around the geometric center of the central support column 21. The inner edge of the distribution plate 22 is fixedly connected to the outer peripheral surface of the central support column 21. A preset gap is maintained between the outer edge of the distribution plate 22 and the inner wall surface of the filter cylinder 10. Multiple water-permeable holes are opened on the distribution plate 22. The water-permeable holes are arranged in an array along the radial direction. An independent filter media receiving cavity is formed between two adjacent layers of distribution plates 22. The central support column 21 has a hollow structure, and multiple drainage holes 211 are opened on the side wall of the central support column 21. The drainage holes 211 are connected to the receiving cavities of each layer of filter media.

[0034] The outer edge gap of the distribution plate: a 2mm×45° chamfer is machined on the outer edge of each distribution plate, and a corresponding annular bevel at the same angle is machined on the inner wall of the filter cylinder; during assembly, an annular gap with a width of 3mm±0.2mm and a height of 2mm is formed between the chamfer and the bevel, and it is filled with φ3mm PTFE round wire to ensure thermal expansion and contraction allowance and prevent filter media leakage.

[0035] Connection between the distribution plate and the central support column: Eight countersunk through holes are evenly distributed on the inner edge of the distribution plate, and eight M10 stainless steel threaded seats are welded at the corresponding height positions of the central support column; after the distribution plate is fitted, the countersunk bolts are coated with thread adhesive, passed through the through holes and screwed into the threaded seats with a torque of 15 N·m. The bolt heads are recessed 1 mm below the plate surface. After welding the sealing ring, the surface is ground flat to form a detachable rigid fixation.

[0036] In the above technical solution, the upper surface of the distribution plate is provided with an annular protrusion structure, which protrudes upward from the upper surface of the distribution plate, and the height of the annular protrusion structure is 2 to 4 times the thickness of the distribution plate.

[0037] Furthermore, in the above technical solution, the permeable holes are circular or elliptical, and the diameter of the permeable holes gradually increases from the inside to the outside along the radial direction of the distribution plate. The ratio of the diameter of the innermost permeable hole to the diameter of the outermost permeable hole is 1:2 to 1:3.

[0038] Furthermore, in the above technical solution, multiple longitudinal reinforcing ribs are provided on the outer peripheral surface of the central support column 21. The longitudinal reinforcing ribs extend along the axial direction of the central support column 21, and the cross-section of the longitudinal reinforcing ribs is triangular or trapezoidal. The bottom edge of the longitudinal reinforcing ribs is fixedly connected to the outer peripheral surface of the central support column 21.

[0039] Furthermore, in the above technical solution, the outer edge of the distribution plate 22 is provided with a downwardly extending annular baffle. The distance between the lower end face of the annular baffle and the upper surface of the next layer of distribution plate 22 is 1 / 3 to 1 / 2 of the height of the filter material receiving cavity. The thickness of the annular baffle is less than the thickness of the distribution plate 22.

[0040] Furthermore, in the above technical solution, a flow guide cone is provided inside the central support column 21, with the cone tip facing the bottom of the central support column 21. An annular flow channel is formed between the side wall of the flow guide cone and the inner wall of the central support column 21, and the drain hole 211 is connected to the annular flow channel.

[0041] Furthermore, in the above technical solution, the distribution plate 22 and the central support column 21 are connected by welding or bolt assembly. When bolt assembly is used, the inner edge of the distribution plate 22 is provided with mounting holes, and the corresponding position of the outer peripheral surface of the central support column 21 is provided with threaded holes. The bolt passes through the mounting holes and is screwed into the threaded holes.

[0042] Furthermore, in the above technical solution, the support frame 20 is made of stainless steel or polypropylene, and the filter cylinder 10 is made of fiberglass or carbon steel.

[0043] Furthermore, in the above technical solution, the lower surface of the distribution plate 22 is provided with a plurality of reinforcing ribs, which are arranged along the radial direction of the distribution plate 22, and the two ends of the reinforcing ribs are respectively connected to the outer peripheral surface of the central support column 21 and the inner side of the outer edge of the distribution plate 22.

[0044] Furthermore, in the above technical solution, a conical base is provided at the bottom of the filter cylinder 10, with the cone apex facing downwards. The bottom end of the central support column 21 is fixedly connected to the cone apex of the conical base. A drain outlet is provided at the lowest point of the conical base, and the diameter of the drain outlet is 1 / 10 to 1 / 5 of the inner diameter of the filter cylinder 10.

[0045] The central support column is connected to the conical base: a φ120mm×25mm deep blind hole is opened at the center of the cone top, and an M16×2.0 thread is machined at the bottom of the hole; a positioning section of the same diameter 25mm and an M16 screw are machined at the bottom of the central support column. After being inserted into the blind hole, the thread engagement length is ≥20mm and the tightening torque is 80N·m. Then, 6 8mm fillet welds are evenly distributed along the circumference and continuously welded. After welding, the surface is ground smooth to achieve triple fixation of positioning, thread, and weld.

[0046] Specific Embodiment 1: The multi-stage filtration media layered support device for sewage treatment in this embodiment is applied to the pretreatment section of an urban sewage treatment plant. The filter cylinder is made of carbon steel with a diameter of 1200mm and a height of 2500mm. The cylinder wall thickness is 8mm, and the inner wall is coated with an epoxy resin anti-corrosion layer. The central support column is made of stainless steel 304 pipe with an outer diameter of 200mm and a wall thickness of 5mm. The total height is 2300mm. Six longitudinal reinforcing ribs are evenly welded along the circumference of the outer circumference of the support column. The reinforcing ribs have a trapezoidal cross-section with a bottom width of 30mm, a top width of 10mm, and a height of 40mm. They are continuously welded along the axial direction. The support frame is equipped with four layers of distribution plates, which are numbered from top to bottom as the first to the fourth layer. The axial spacing between the plates is 500mm. Each layer of distribution plates is made of 6mm thick 304 stainless steel, in the shape of a ring, with an inner diameter of 210mm, fitted around the outer perimeter of the central support column, and an outer diameter of 1150mm. The inner edge of the distribution plate is welded to the outer perimeter of the central support column by continuous fillet welds, with a weld height of 4mm. The first layer of distribution plates has a total of 120 permeable holes, with the hole diameter gradually increasing from 15mm in the inner circle to 40mm in the outer circle, distributed in a concentric array of 6 rings. The permeable hole arrangement of the second to fourth layers of distribution plates is the same as that of the first layer. On the upper surface of each layer of distribution plates, a ring-shaped protrusion structure is welded 80mm inward from the outer edge. The protrusion is 15mm high, 20mm wide, and has a semi-circular cross-section. The outer edge of the distribution plate is welded downward. The ring-shaped baffle is 180mm high and 4mm thick. Twelve reinforcing ribs, made of equilateral angle steel with sides of 25mm and a thickness of 3mm, are welded radially to the lower surface of each distribution plate. One end of each rib is welded to the outer circumference of the central support column, and the other end to the inner edge of the distribution plate. Drainage holes, 8 in total, are evenly distributed around the circumference of each layer, located 50mm below the corresponding position on each layer's distribution plate. The holes have a diameter of 25mm. A guide cone, made of rolled and welded 304 stainless steel, is installed inside the central support column. The cone has a 60-degree apex angle, located 100mm above the bottom of the support column, and a 180mm diameter base, located 200mm below the fourth layer's distribution plate. The cone's sidewall... The annular flow channel between the filter cylinder and the inner wall of the support column is 10mm wide. A conical base with a 45-degree angle and a height of 300mm is welded to the bottom of the filter cylinder. A 120mm diameter drain outlet with a valve is located at the top of the cone. After installation, the first layer of filter media is filled with 30mm-35mm ceramsite filter media to a height of 420mm. The second layer is filled with 10mm-12mm quartz sand filter media to a height of 400mm. The third layer is filled with 5mm-7mm quartz sand filter media to a height of 380mm. The fourth layer is filled with 2mm-3mm fine sand filter media to a height of 350mm. The system is designed to process 15 cubic meters of wastewater per hour.The influent suspended solids concentration is 200 mg / L to 500 mg / L. After filtration by this device, the effluent suspended solids concentration is reduced. The filter media backwashing cycle is once every 72 hours of operation, with a backwashing intensity of 15 liters per square meter per second and a backwashing time of 15 minutes. The entire device has a compact structure, occupies only 1.5 m², is easy to install, operates stably, and is simple to maintain.

[0047] Specific Embodiment 2: This Embodiment 2 is based on Embodiment 1, but the material of the central support column is changed to polypropylene. A polypropylene pipe with an outer diameter of 220mm and a wall thickness of 8mm is used. The longitudinal reinforcing ribs are made of the same polypropylene profiles and are fixed to the outer circumference of the support column by hot-melt welding. The reinforcing ribs have a triangular cross-section with a base width of 35mm and a height of 45mm. The distribution plate is also made of polypropylene sheet, but the thickness is increased to 10mm to compensate for insufficient material strength. The distribution plate is connected to the central support column using a bolt assembly. A bolt with a diameter of [missing information] is cut every 60 degrees along the inner edge of the distribution plate. The mounting holes are 12mm in diameter, and M10 threaded holes are tapped at the corresponding positions on the outer circumference of the central support column. Stainless steel bolts are passed through the mounting holes and screwed into the threaded holes. The bolt tightening torque is 20 Nm to 25 Nm. This connection method facilitates on-site assembly and subsequent maintenance. The filter cylinder is made of fiberglass with a thickness of 6mm, which reduces the weight by about 40% compared to the carbon steel cylinder. The guide cone is also made of polypropylene sheet rolled and formed by hot melt welding. The weight of the entire device is further reduced, making it more convenient to handle and install. It is suitable for occasions with strict requirements on equipment weight. The remaining structural parameters and usage methods are the same as in Example 1.

[0048] Specifically, the principle of this utility model is as follows: This utility model adopts an integrated support frame composed of a central support column and multiple distribution plates, fundamentally changing the structural form of traditional multi-stage filtration devices. The central support column serves as the main vertical load-bearing component, and its hollow structure not only reduces its own weight but also serves as a drainage channel. Multiple distribution plates are arranged around the central support column, with the inner edge of each distribution plate fixed to the outer circumference of the central support column, and a preset gap maintained between the outer edge and the inner wall of the filter cylinder. This structural design allows each distribution plate to reliably bear the weight of the upper filter media and transfer the load to the central support column. The array distribution of permeable holes on the distribution plates ensures that water can pass through evenly. The design of the permeable hole diameter increasing radially conforms to the natural law of water flow gradually dispersing from the center to the periphery. The smaller diameter of the inner ring improves the interception capacity of fine particles, while the larger diameter of the outer ring increases the overall water permeability. The filter media receiving cavity formed between two adjacent distribution plates provides independent receiving space for filter media of different particle sizes. The upper layer is filled with coarse particle filter media to intercept large-diameter suspended solids, and the lower layer is filled with fine particle filter media to further remove small-diameter particles. Impurities are filtered in stages from coarse to fine. The annular raised structure on the upper surface of the distribution plate and the annular baffle on the outer edge form a double constraint, preventing the filter media from mixing between layers or leaking out through gaps under the action of water flow. After the sewage enters from the top of the filter cylinder, it first comes into contact with the uppermost layer of coarse filter media. Under the action of gravity, it permeates downward. After being filtered through each layer of filter media, the clean water enters the lower space of the filter media receiving cavity through the water permeable holes on the distribution plate, and then enters the hollow support column through the drainage holes on the side wall of the central support column. The guide cone inside the central support column guides the water flow to flow smoothly downward and finally discharges from the bottom of the support column. This centralized drainage method avoids the problems of uneven pressure and unreasonable flow distribution caused by multi-point drainage. The conical base at the bottom of the filter cylinder causes the deposited sludge to accumulate at the lowest point and is discharged periodically through the sewage outlet. The setting of longitudinal and radial reinforcing ribs significantly improves the overall rigidity of the support frame, enabling the device to withstand the weight of the filter media and the water flow pressure. The technical principle of this utility model is scientific and reasonable, and the various components work together to form a highly efficient and stable multi-stage filtration system.

Claims

1. A layered support device for multi-stage filtration in wastewater treatment, comprising a filter cylinder and a support frame, wherein the support frame is disposed inside the filter cylinder, characterized in that, The support frame includes a central support column and multiple distribution plates. The central support column extends vertically, and the distribution plates are spaced apart along the axial direction of the central support column. Each layer of distribution plates has a ring structure and is arranged around the geometric center of the central support column. The inner edge of the distribution plate is fixedly connected to the outer circumferential surface of the central support column, and a preset gap is maintained between the outer edge of the distribution plate and the inner wall surface of the filter cylinder. Multiple water-permeable holes are provided on the distribution plates, and the water-permeable holes are arranged in an array along the radial direction. An independent filter media receiving cavity is formed between two adjacent layers of distribution plates. The central support column has a hollow structure, and multiple drainage holes are provided on the side wall of the central support column. The drainage holes are connected to the receiving cavities of each layer of filter media.

2. The filter media layering support device for multi-stage filtration in wastewater treatment according to claim 1, characterized in that, The upper surface of the distribution plate is provided with an annular protrusion structure, which protrudes upward from the upper surface of the distribution plate, and the height of the annular protrusion structure is 2 to 4 times the thickness of the distribution plate.

3. The filter media layering support device for multi-stage filtration in wastewater treatment according to claim 2, characterized in that, The permeable holes are circular or elliptical, and the diameter of the permeable holes gradually increases from the inside to the outside along the radial direction of the distribution plate. The ratio of the diameter of the innermost permeable hole to the diameter of the outermost permeable hole is 1:2 to 1:

3.

4. The filter media layering support device for multi-stage filtration in wastewater treatment according to claim 3, characterized in that, The outer circumferential surface of the central support column is provided with multiple longitudinal reinforcing ribs. The longitudinal reinforcing ribs extend along the axial direction of the central support column. The cross-section of the longitudinal reinforcing ribs is triangular or trapezoidal. The bottom edge of the longitudinal reinforcing ribs is fixedly connected to the outer circumferential surface of the central support column.

5. The filter media layering support device for multi-stage filtration in wastewater treatment according to claim 4, characterized in that, The outer edge of the distribution plate is provided with a downwardly extending annular baffle. The distance between the lower end face of the annular baffle and the upper surface of the next layer of distribution plate is 1 / 3 to 1 / 2 of the height of the filter material receiving cavity. The thickness of the annular baffle is less than the thickness of the distribution plate.

6. The filter media layering support device for multi-stage filtration in wastewater treatment according to claim 5, characterized in that, The central support column has a flow guide cone inside, with the cone tip facing the bottom of the central support column. The side wall of the flow guide cone and the inner wall of the central support column form an annular flow channel, and the drain hole is connected to the annular flow channel.

7. The filter media layering support device for multi-stage filtration in wastewater treatment according to claim 6, characterized in that, The distribution plate and the central support column are connected by welding or bolt assembly. When bolt assembly is used, the inner edge of the distribution plate is provided with mounting holes, and the corresponding position of the outer circumferential surface of the central support column is provided with threaded holes. The bolt passes through the mounting holes and is screwed into the threaded holes.

8. The filter media layering support device for multi-stage filtration in wastewater treatment according to claim 7, characterized in that, The support frame is made of stainless steel or polypropylene, and the filter cylinder is made of fiberglass or carbon steel.

9. A filter media layering support device for multi-stage filtration in wastewater treatment according to claim 8, characterized in that, The lower surface of the distribution plate is provided with a plurality of reinforcing ribs, which are arranged along the radial direction of the distribution plate. The two ends of the reinforcing ribs are respectively connected to the outer peripheral surface of the central support column and the inner side of the outer edge of the distribution plate.

10. A filter media layering support device for multi-stage filtration in wastewater treatment according to claim 9, characterized in that, The bottom of the filter cylinder is provided with a conical base, with the cone apex facing downwards. The bottom end of the central support column is fixedly connected to the cone apex of the conical base. A drain outlet is provided at the lowest point of the conical base, and the diameter of the drain outlet is 1 / 10 to 1 / 5 of the inner diameter of the filter cylinder.

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