Uniform water and air distribution device for filter backwash

Abstract

The utility model discloses a filter tank backwash even water distribution air distribution device belongs to water treatment equipment technical field, including filter tank, and the filter tank is equipped with filter material, the bottom of filter tank is provided with gas water main pipe, and the both sides of gas water main pipe lower part are provided with water passing hole, and a plurality of water passing holes are arranged at intervals, the top of gas water main pipe is provided with air distribution branch pipe, and the upper portion of air distribution branch pipe is in the outside of gas water main pipe, and the lower part of air distribution branch pipe is in the inside of gas water main pipe, the upper end of air distribution branch pipe is provided with filter plate, and the filter head is set up on filter plate. When the gas water combined backwash, the gas water is layered in the main pipe because of the density difference, realizes even air distribution and water distribution through twice air cushion layer effect, avoids the uneven problem of regional intensity of traditional mode, and improves backwash effect. The overall structure is compatible with separate water washing, gas washing and combined washing, ensures that water distribution and air distribution are even under all kinds of working conditions. Air distribution branch pipe adopts threaded insertion type fixation, can be disassembled single, and maintenance is convenient, and the aperture combination is flexible, adapts to various filter tank structures and parameters, and the versatility is strong.

Description

Technical Field

[0001] This utility model belongs to the technical field of water treatment equipment, specifically relating to a filter backwashing device for uniform water and air distribution. Background Technology

[0002] The statements in this section are merely background information related to this utility model and do not necessarily constitute prior art.

[0003] Backwashing of filters is a crucial operation for removing contaminants trapped in the filter media and restoring filtration capacity. Its principle involves using reverse water flow or a combination of water and air to cause friction and collision among the filter media particles, stripping away impurities and discharging them. Filter backwashing can be performed using air washing, water washing, or a combined air-water backwash. Typically, air and water inlet pipes are connected to the space below the filter plates, and water and air are distributed through the filter heads on the plates. However, this method results in poor uniformity of air and water distribution, easily leading to high pressure in the air and water inlet areas. Most of the air and water enters the filter heads from the pipe outlet, causing excessively high backwash intensity in some areas and low backwash intensity in others, creating dead zones that fail to achieve the desired backwashing effect, resulting in low backwashing efficiency.

[0004] Even worse, excessive pressure on the filter heads on the filter plate can cause them to detach, leading to filter media falling below the filter plate and causing material leakage, which can also clog the pipes. To overcome this problem, multiple branch pipes are sometimes distributed evenly under the filter plate. Although this results in a more uniform air-water distribution, the problem of excessively high local pressure at the pipe outlet still exists, and the backwashing intensity varies greatly. Moreover, the space below the filter plate is usually small, and the construction and maintenance difficulty of installing multiple branch pipes is further increased. Utility Model Content

[0005] To address the aforementioned problems, this invention provides a filter backwashing device for uniform water and air distribution. During combined air and water backwashing, the air and water separate into layers within the main pipe due to density differences. Uniform air and water distribution is achieved through two air cushion layers, avoiding the uneven intensity issues of traditional methods and improving the backwashing effect. The overall structure is compatible with individual water washing, air washing, and combined washing, ensuring uniform water and air distribution under various operating conditions. The air distribution branch pipes are fixed using a threaded insertion method, allowing for individual disassembly and convenient maintenance. Furthermore, the flexible combination of holes and slots adapts to various filter structures and parameters, demonstrating strong versatility.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A filter backwashing uniform water and air distribution device includes a filter tank containing filter media; a main air-water pipe is provided at the bottom of the filter tank, with water passage holes on both sides of the lower part of the main air-water pipe, the water passage holes being spaced out; an air distribution branch pipe is provided at the top of the main air-water pipe, the upper end of the air distribution branch pipe being outside the main air-water pipe, and the lower end of the air distribution branch pipe being inside the main air-water pipe; a filter plate is provided at the upper end of the air distribution branch pipe, and filter heads are provided on the filter plate.

[0007] As a further technical solution, the upper end of the filter plate is a support layer, and the upper end of the support layer is the filter material; the upper end of the filter head is located within the support layer, and several filter heads are arranged at intervals.

[0008] As a further technical solution, the filter pool has a square structure, and an air and water inlet mechanism is provided on the side of the filter pool.

[0009] As a further technical solution, the air intake and water intake mechanism includes an air intake pipe, a water intake pipe, an air intake valve, and a water intake valve, wherein an air intake valve is provided on the air intake pipe and a water intake valve is provided on the water intake pipe.

[0010] As a further technical solution, the air inlet pipe and the water inlet pipe are connected, and the water inlet pipe is connected to the main air and water pipe.

[0011] As a further technical solution, several gas distribution branch pipes are arranged at intervals, and the gas distribution branch pipes are connected to the gas and water main pipes; the top surface of the gas distribution branch pipe is sealed, the bottom surface is sealed, or it is open.

[0012] As a further technical solution, the upper part of the air distribution branch pipe is provided with a side opening, which is a hole, a horizontal air gap, or a vertical air gap.

[0013] As a further technical solution, a fixing thread is provided in the middle of the gas distribution branch pipe.

[0014] As a further technical solution, the lower part of the air distribution branch pipe is provided with a lower first side opening, which is a side air hole or a vertical air slit.

[0015] As a further technical solution, the lower part of the air distribution branch pipe is also provided with a lower second bottom opening, and the lower second side opening is a side air hole or a vertical air slit.

[0016] Compared with the prior art, the advantages and positive effects of this utility model are: In this invention, during combined air-water backwashing, air and water enter the main pipe simultaneously. Due to the density difference, the air and water automatically form stratification. Affected by the air outlet resistance, the gas forms a first air cushion layer in the upper part of the main pipe and then enters the bottom space of the filter plate evenly through the air distribution branch pipe. The water enters the bottom space of the filter plate through the water passage. After passing through the device, the air and water achieve the initial air-water pre-distribution purpose. The air and water form a second air cushion layer in the lower space of the filter plate. Then, the air and water enter the filter media layer evenly through the filter head on the filter plate for backwashing. After the action of the two air cushion layers, the air distribution in the whole pool is more uniform, and the backwashing intensity distribution in the whole pool is more uniform. This avoids the situation in the traditional method where the intensity is too high in the area near the water inlet and air inlet, causing the filter media and support layer to tumble violently, while the intensity is low in the far end and the filter media cannot be loosened. This can significantly improve the backwashing effect.

[0017] The overall structure of this utility model can be adapted to separate water washing or separate air washing, and can also be applied to combined air and water backwashing. In separate water washing, water passes through both the water passage and the air distribution branch pipe, achieving uniform water distribution throughout the tank. In separate air washing, gas passes evenly through the air distribution branch pipe, achieving uniform air washing intensity throughout the tank. In combined air and water backwashing, air and water automatically separate into layers in the main pipe. Gas passes through the air distribution branch pipe, and water passes through the water passage, achieving initial pre-distribution. Then, through the filter head on the filter plate, and through the action of two air cushion layers, uniform air and water distribution throughout the tank is achieved.

[0018] The air distribution branch pipe of this utility model is fixed by threaded insertion and can be disassembled individually, making maintenance and repair convenient; moreover, the combination of holes and slots in the upper and lower sections of the air distribution branch pipe is flexible and diverse, and can be freely selected according to the filter tank structure and filter media type, and can also be designed according to the backwashing intensity, filter media type and water pump / fan parameters, making it highly versatile. Attached Figure Description

[0019] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments of this utility model and their descriptions are used to explain this utility model and do not constitute an improper limitation of this utility model.

[0020] Figure 1 This is a schematic diagram of the filter backwashing uniform water and air distribution device of this utility model. Figure 2 This is a schematic diagram of the water and air distribution structure system of this utility model. Figure 1 ; Figure 3 This is a schematic diagram of the water and air distribution structure system of this utility model. Figure 2 ; Figure 4 This is a schematic diagram of the air inlet and outlet arrangement of the air distribution branch pipe of this utility model. Figure 1 ; Figure 5 This is a schematic diagram of the air inlet and outlet arrangement of the air distribution branch pipe of this utility model. Figure 2 ; Figure 6 This is a schematic diagram illustrating the working principle of this utility model; In the diagram: 1. Filter media; 2. Air inlet pipe; 3. Water inlet valve; 4. Main air and water pipe; 5. Water passage hole; 6. Air distribution branch pipe; 61. Upper side opening; 62. Fixing thread; 63. Lower first side opening; 64. Lower second side opening; 7. Filter head; 8. Air inlet valve; 9. Water inlet pipe; 10. Filter tank; 11. Filter plate. Detailed Implementation

[0021] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0022] Filter backwashing can be done by air washing, water washing, or combined air and water backwashing. Usually, air inlet pipes and water inlet pipes are connected to the space under the filter plate, and water and air are distributed through the filter head on the filter plate. However, this method of water and air distribution has poor uniformity of air and water distribution, which can easily lead to high pressure in the air and water inlet areas. Most of the air and water enter the filter head from the pipe outlet, resulting in excessively high backwashing intensity in some areas and low backwashing intensity in others. This creates dead zones that cannot achieve the backwashing effect, resulting in low backwashing efficiency. Even worse, excessive pressure on the filter heads on the filter plate can cause them to detach, leading to filter media falling below the filter plate and causing material leakage, which can also clog the pipes. To overcome this problem, multiple branch pipes are sometimes distributed evenly under the filter plate. Although this results in a more uniform air-water distribution, the problem of excessively high local pressure at the pipe outlet still exists, and the backwashing intensity varies greatly. Moreover, the space below the filter plate is usually small, and the construction and maintenance difficulty of installing multiple branch pipes is further increased.

[0023] The present invention will now be described in detail with reference to the accompanying drawings. This embodiment discloses a filter backwashing uniform water and air distribution device, such as... Figure 1 , Figure 2 as well as Figure 3 As shown, the system includes a filter tank containing filter media; a main air-water pipe is located at the bottom of the filter tank, with water passage holes on both sides of the lower part of the main air-water pipe, spaced at intervals; an air distribution branch pipe is located at the top of the main air-water pipe, with the upper end of the branch pipe outside the main air-water pipe and the lower end inside the main air-water pipe; a filter plate is located at the upper end of the branch pipe, and filter heads are installed on the filter plate.

[0024] Specifically, during combined air-water backwashing, air and water enter the main pipe simultaneously. Due to the density difference, the air and water automatically form stratification. Affected by the air outlet resistance, the gas forms a first air cushion layer in the upper part of the main pipe and then enters the bottom space of the filter plate evenly through the air distribution branch pipe. The water enters the bottom space of the filter plate through the water passage. After passing through this device, the air and water achieve the initial air and water pre-distribution purpose. The air and water form a second air cushion layer in the lower space of the filter plate. Then, the air and water enter the filter media layer evenly through the filter head on the filter plate for backwashing. After the action of the two air cushion layers, the air distribution in the whole pool is more uniform, and the backwashing intensity distribution in the whole pool is more uniform. This avoids the situation in the traditional method where the intensity is too high in the area near the water inlet and air inlet, causing the filter media and support layer to churn violently, while the intensity is low in the far end and the filter media cannot be loosened. This can significantly improve the backwashing effect.

[0025] The overall structure of this utility model can be adapted to separate water washing or separate air washing, and can also be applied to combined air and water backwashing. In separate water washing, water passes through both the water passage and the air distribution branch pipe, achieving uniform water distribution throughout the tank. In separate air washing, gas is evenly distributed through the air distribution branch pipe, achieving consistent air washing intensity throughout the tank. In combined air and water backwashing, air and water automatically separate into layers in the main pipe. Gas passes through the air distribution branch pipe, and water passes through the water passage, achieving initial pre-distribution. Then, through the filter head on the filter plate, and through the action of two air cushion layers, uniform air and water distribution throughout the tank is achieved.

[0026] The upper end of the filter plate is a support layer, and the upper end of the support layer is the filter media; the upper end of the filter head is located within the support layer, and several filter heads are spaced apart. Several air distribution branch pipes are spaced apart, and the air distribution branch pipes are connected to the main air-water pipes; the top surface of the air distribution branch pipes is sealed, the bottom surface is sealed, or it is open.

[0027] Specifically, the main system of the filter tank is a conventional filter tank structure. The tank body is square or rectangular, with water inlet at the top and water outlet at the bottom. The interior of the tank body consists of filter media, support layer, and filter plate from top to bottom. Conventional filter heads are installed on the filter plate, and backwash water inlet and air inlet pipes are installed on the tank wall below the filter plate.

[0028] Specifically, the raw water to be treated enters from the top of the filter bed, flows sequentially through the filter media layer, support layer, filter plate, and filter head, and is finally discharged from the effluent system at the bottom of the filter bed. During this process, pollutants in the water are trapped by the filter media layer, achieving water purification.

[0029] The support layer is a layer of granular material located below the filter media layer and above the filter plate. It is usually made of quartz sand, pebbles, etc. Its main function is to support the filter media layer, prevent filter media particles from leaking out from the gaps in the filter head of the filter plate, and evenly distribute the water flow and air flow during backwashing to avoid excessive local impact force that could cause the filter media layer to loosen or be lost.

[0030] The main air-water pipe and the branch air distribution pipe are made of stainless steel. The main air-water pipe connects to the backwash water and air inlet pipe of the pool wall. There can be one or multiple main air-water pipes, depending on the filtration area. The main air-water pipe is a round pipe. Several water passage holes are set at 45° intervals on both sides of the lower part of the main air-water pipe for backwash water outlet. The diameter of the water passage holes is 20mm~40mm. The total area of ​​the water passage holes on the main air-water pipe is 0.8~1.2 times the cross-sectional area of ​​the main air-water pipe.

[0031] Several air distribution branch pipes are vertically installed at the top of the air-water main pipe. The number of air distribution branch pipes is related to the filtration area. Each air distribution branch pipe corresponds to 20 to 30 filter heads on the filter plate and is located in the middle of the corresponding filter heads. The air distribution branch pipes are fastened to the top of the air-water main pipe by threads. External threads are provided at 1 / 2 height of the air distribution branch pipes. Internal threaded holes are provided at intervals at the top of the air-water main pipe.

[0032] The diameter of the air distribution branch pipe is 15~32mm, and it is divided into upper and lower parts. The area above the external thread is the air outlet area, and the area below the external thread is the air inlet area. The top surface of the air outlet area is sealed, and the side is provided with air outlet holes or air outlet slits. The air outlet slits can be horizontal or vertical. The total area of ​​the air outlet holes or air outlet slits of each air distribution branch pipe is 1.0~1.5 times the cross-sectional area of ​​the air distribution branch pipe, which can ensure low air outlet resistance and large air outlet volume.

[0033] Specifically, the bottom surface of the air intake area can be sealed or open. When the bottom surface is sealed, air intake holes or slits are provided on the sides. The diameter of the air holes is 2-3 mm, and the air intake slits are vertical slits with a width of 2-3 mm. The number of air holes or slits gradually increases from top to bottom. The total area of ​​the air holes or slits is 0.8-1.0 times the cross-sectional area of ​​the air distribution branch pipe, forming air intake resistance. The resistance is greater at the top and smaller at the bottom, which facilitates the formation of a stable air cushion layer in the upper space inside the air-water main pipe; bottom surface When open, a small number of air inlets or air slits are provided on the side. The diameter of the air inlets is 2-3 mm, and the air slits are vertical air slits with a width of 2-3 mm. The air inlets or air slits are evenly arranged in the height direction. The total area of ​​the air inlets or air slits is 0.2-0.3 times the cross-sectional area of ​​the air distribution branch pipe, which forms air intake resistance and facilitates the formation of a stable air cushion layer in the upper space inside the air and water main pipe. When the lower surface of the air cushion layer reaches the bottom of the air distribution area, the gas enters the air distribution branch pipe from the bottom opening.

[0034] The filter has a square structure, with an air and water inlet mechanism installed on its side. This mechanism includes an air inlet pipe, a water inlet pipe, an air inlet valve, and a water inlet valve. An air inlet valve is installed on the air inlet pipe, and a water inlet valve is installed on the water inlet pipe. The air inlet pipe and the water inlet pipe are connected, and the water inlet pipe is connected to the main air and water pipe.

[0035] The air and water inlet mechanism is used to transport water and air. Water is transported to the air-water main pipe through the water inlet pipe. When water needs to be transported, the corresponding delivery pump is started and the water inlet valve is opened to transport water. Air is transported to the air-water main pipe through the air inlet pipe. When air needs to be transported, the corresponding air delivery pump is started and the air inlet valve is opened to transport air.

[0036] A fixing thread is provided in the middle of the gas distribution branch pipe.

[0037] Specifically, the air distribution branch pipe is fixed by threaded insertion and can be disassembled individually, making maintenance and repair convenient; moreover, the combination of holes and slots in the upper and lower sections of the air distribution branch pipe is flexible and diverse, and can be freely selected according to the filter tank structure and filter media type, and can also be designed according to the backwashing intensity, filter media type and water pump / fan parameters, making it highly versatile.

[0038] The upper part of the air distribution branch pipe is provided with a side opening, which can be a hole, a horizontal air slit, or a vertical air slit.

[0039] The lower part of the air distribution branch pipe is provided with a first side opening, which is either a side vent or a vertical air slit. The lower part of the air distribution branch pipe is also provided with a second side opening, which is either a side vent or a vertical air slit.

[0040] Specifically, gas distribution branch pipes can be selected according to actual needs. They can be divided into gas distribution branch pipe A and gas distribution branch pipe B. The bottom surface of gas distribution branch pipe A is sealed, while the bottom surface of gas distribution branch pipe B is open.

[0041] like Figure 4 As shown, when using air distribution branch pipe A, it can be used for separate water washing or air washing, or for combined air and water backwashing. When combined air and water backwashing is running, air and water enter the main air and water pipe simultaneously. Due to factors such as density and pressure, the air and water automatically separate into layers, with air on top and water at the bottom. Due to the air inlet slits in the air distribution branch pipe, the gas pressure further increases, forming a stable air cushion layer. Gas enters the air distribution branch pipe through the upper air inlet slits. As the gas further enters, the gas pressure in the main pipe increases, and the air cushion layer moves downward until it reaches the bottom of the air inlet area. All the gas enters the air distribution branch pipe through the air inlet slits, and then escapes through the air outlet slits into the space under the filter plate. Water enters the space under the filter plate through the water passage holes, completing the initial air and water pre-distribution. Then, after passing through the filter head on the filter plate, it evenly enters the support layer and filter media layer.

[0042] like Figure 5As shown, when using the air distribution branch pipe B, it can be used for separate water washing or air washing, or for combined air and water backwashing. When the combined air and water backwashing is running, air and water enter the main air and water pipe simultaneously. Due to factors such as density and pressure, the air and water automatically separate into layers, with air on top and water at the bottom. Due to the air inlet slit of the air distribution branch pipe, the gas pressure further increases, forming a stable air cushion layer. The gas enters the air distribution branch pipe through the upper air inlet slit. As the gas further enters, the gas pressure in the main pipe increases rapidly, and the air cushion layer quickly moves down to the bottom of the air inlet area. Then, the gas enters the air distribution branch pipe through the bottom open air inlet pipe, and then escapes through the air outlet slit into the space under the filter plate. Water enters the space under the filter plate through the water passage, completing the initial air and water pre-distribution. Then, after passing through the filter head on the filter plate, it evenly enters the support layer and filter media layer.

[0043] Working principle of the filter backwash uniform water and air distribution device: like Figure 6 As shown, air-water combined backwashing: air and water are automatically stratified and initially pre-distributed. After the backwashing gas and water enter the air-water main pipe through the air inlet pipe and water inlet pipe, they are automatically stratified due to density differences, with gas on top and water at the bottom.

[0044] Due to the resistance from the air inlet or slit of the air distribution branch pipe, the gas forms a first air cushion layer at the top of the main air-water pipe. It then enters the branch pipe through side air holes, vertical air slits, or bottom openings, and escapes from the upper side openings (side holes or air slits) to the bottom space of the filter plate. Water flows directly into the bottom space of the filter plate through the water passages on both sides of the lower part of the main air-water pipe.

[0045] Secondary air cushion layer and uniform water and air distribution: The gas and water entering the space at the bottom of the filter plate form a second air cushion layer, making the pressure distribution under the filter plate more uniform. Finally, the gas and water enter the filter media layer evenly through the filter heads on the filter plate, achieving backwashing. The effect of the two air cushion layers can avoid the problems of excessively high pressure near the air inlet and water inlet and insufficient pressure at the far end in the traditional method, ensuring consistent backwashing intensity throughout the entire tank.

[0046] Individual water washing mode: When only backwash water enters the air-water main pipe, water simultaneously flows into the bottom space of the filter plate through the water passage and the air distribution branch pipe, and enters the filter media layer evenly through the filter head to achieve uniform water washing.

[0047] Standalone air washing mode: When only backwash gas enters the main air-water pipe, the gas forms an air cushion layer at the top of the main air-water pipe, and then enters the bottom space of the filter plate evenly through the air distribution branch pipe, and then enters the filter media layer evenly through the filter head to achieve uniform air washing.

[0048] Although the specific embodiments of the present utility model have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present utility model. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solution of the present utility model are still within the scope of protection of the present utility model.

Claims

1. A filter backwashing device for uniform water and air distribution, characterized in that, The system includes a filter tank containing filter media; a main air-water pipe is located at the bottom of the filter tank, with water passage holes on both sides of the lower part of the main air-water pipe, the water passage holes being spaced out in a plurality of places; an air distribution branch pipe is located at the top of the main air-water pipe, the upper end of the air distribution branch pipe being outside the main air-water pipe, and the lower end of the air distribution branch pipe being inside the main air-water pipe; a filter plate is located at the upper end of the air distribution branch pipe, and a filter head is located on the filter plate.

2. The filter backwashing uniform water and air distribution device as described in claim 1, characterized in that, The upper end of the filter plate is a support layer, and the upper end of the support layer is the filter material; the upper end of the filter head is located within the support layer, and several filter heads are arranged at intervals.

3. The filter backwashing uniform water and air distribution device as described in claim 1, characterized in that, The filter tank has a square structure, and an air and water inlet mechanism is provided on the side of the filter tank.

4. The filter backwashing uniform water and air distribution device as described in claim 3, characterized in that, The air and water intake mechanism includes an air intake pipe, a water intake pipe, an air intake valve, and a water intake valve. An air intake valve is installed on the air intake pipe, and a water intake valve is installed on the water intake pipe.

5. A filter backwashing uniform water and air distribution device as described in claim 4, characterized in that, The air intake pipe is connected to the water intake pipe, and the water intake pipe is connected to the main air and water pipe.

6. The filter backwashing uniform water and air distribution device as described in claim 1, characterized in that, Several gas distribution branch pipes are arranged at intervals, and the gas distribution branch pipes are connected to the gas and water main pipes; the top surface of the gas distribution branch pipe is sealed, the bottom surface is sealed or open.

7. A filter backwashing uniform water and air distribution device as described in claim 1, characterized in that, The upper part of the air distribution branch pipe is provided with a side opening, which can be a side hole, a horizontal air slit, or a vertical air slit.

8. The filter backwashing uniform water and air distribution device as described in claim 1, characterized in that, The gas distribution branch pipe is provided with a fixing thread in the middle.

9. A filter backwashing uniform water and air distribution device as described in claim 1, characterized in that, The lower part of the air distribution branch pipe is provided with a first side opening, which is a side air hole or a vertical air slit.

10. A filter backwashing uniform water and air distribution device as described in claim 1, characterized in that, The lower part of the air distribution branch pipe is also provided with a second side opening, which is a side air hole or a vertical air slit.

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