Device for reducing filter material loss for filter tank
By installing a sand interception trough device on the side wall of the filter bed drainage channel, the filter media particles are made to sink to the bottom of the trough and flow back by gravity, which solves the problem of filter media loss, achieves effective retention of filter media and stability of filtration effect, and reduces operating costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- BEIJING GENERAL MUNICIPAL ENG DESIGN & RES INST
- Filing Date
- 2025-05-21
- Publication Date
- 2026-04-28
AI Technical Summary
During the backwashing process of the V-type filter in the water supply plant, fine filter media particles are easily carried into the drainage ditch by the backwash water, resulting in filter media loss, which is difficult to control effectively with existing technology.
Design a sand interception trough device, which is installed on the side wall of the H-shaped drainage ditch of the filter pool. The sand interception trough is wider at the top and narrower at the bottom. The filter media particles sink to the bottom of the trough and flow back to the sand layer by gravity, thus preventing them from flowing into the drainage ditch.
It effectively reduces filter media loss, ensures the stability of filter bed filtration effect, reduces the need for filter media replenishment, simplifies installation and operation, and reduces operating costs.
Smart Images
Figure CN224166975U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a device that can be applied to reduce the loss of filter media during the backwashing and drainage process of filter beds in the field of municipal water supply treatment. Background Technology
[0002] Water treatment plant filtration processes often employ V-shaped filters, where water flows from top to bottom through the filter bed to remove impurities. To ensure the filter's effectiveness, after a period of operation, a combination of water and air is used to backwash the filter media from bottom to top. The backwash wastewater is discharged through an H-shaped drainage channel. During this process, due to the impact of the backwash water (air-water), finely worn filter media particles are often carried into the drainage channel, causing filter media loss.
[0003] Currently, backwash drainage in V-type filters is discharged from the drainage channel in the middle of each filter compartment. The drainage channel is generally made of reinforced concrete with a slanted triangular structure at the top. To control filter media loss, the backwash intensity is usually controlled, but it is still unavoidable that some fine filter media particles that have been worn over time are lost with the backwash water flow. Utility Model Content
[0004] This invention provides a device for reducing filter media loss in filter beds.
[0005] The present invention relates to a device for reducing filter media loss in a filter bed, characterized in that the device includes a sand-cutting trough and a fixing device. The sand-cutting trough is wider at the top and narrower at the bottom, and is shaped like a funnel with a sand discharge hole at the bottom. The sand-cutting trough is installed on the side wall of the H-shaped drainage channel of the filter bed near the filter media via the fixing device.
[0006] Preferably, the fixing device includes a fixing bolt and a fixing nut.
[0007] Preferably, the sand-cutting trough is made of stainless steel with a wall thickness of 1-3 mm.
[0008] Preferably, the distance 'a' between the lower end of the sand interception trough and the side wall of the drainage ditch is 5-8 cm.
[0009] Preferably, the distance b between the upper end of the sand interception trough and the side wall of the drainage ditch is 15-20cm.
[0010] Preferably, the distance c between the upper edge of the sand interception trough and the upper edge of the drainage ditch is 5-8cm.
[0011] Preferably, the sand interception trough is divided into three sections: an upper section, a middle section, and a lower section. The height d of the upper section is 15-20cm, the height e of the middle section is 15-20cm, and the height f of the lower section is 5-10cm.
[0012] Preferably, the angle x at the bend between the middle and lower half of the sand-cutting groove is 30°-60°.
[0013] Preferably, the sand interception groove is fixed to the side wall of the H-shaped drainage ditch using stainless steel fixing bolts and nuts, with the bolt plane spacing L being 30-60cm.
[0014] This utility model relates to a filter bed device that reduces filter media loss. The sand interception trough is inexpensive, simple in structure, and easy to install. It can be directly fixed to the drainage ditch with bolts without affecting the existing structure of the filter bed or the backwashing effect. The sand interception trough designed in this utility model can be used in V-type filters as well as other types of filters; it can be used in new water supply plant structures as well as in the renovation of existing structures. It can be installed manually at any time and has broad application value in practical engineering. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the installation of the device for reducing filter media loss in the filter bed according to this utility model.
[0016] Figure 2-4 This is a schematic diagram of three directions of the device for reducing filter media loss in the filter bed according to this utility model.
[0017] Reference numerals: 1-Gateway, 2, 3-Fixing nuts, 4, 5-Fixing bolts, 6, 7-Fixing nuts. Detailed Implementation
[0018] See Figure 1 The water treatment plant employs a V-type filter process. A device to reduce filter media loss is installed on the H-shaped drainage channel of the filter. This device is mounted on the side wall of the H-shaped drainage channel, on the side closest to the filter media. When the filter is backwashed, the fine filter media particles carried by the backwash water flowing into the drainage channel from above the sand layer first enter the upper part of the sand interception trough, then sink to the bottom of the sand interception trough, and flow back to the sand layer through the lower gaps, thus preventing the loss of sand filter media.
[0019] The sand-cutting groove is as follows Figure 2-4 The structure consists of the following parts: trough 1, fixing nuts 2 and 3, fixing bolts 4 and 5, and fixing nuts 6 and 7. The trough 1 is made of stainless steel with a wall thickness of 1-3 mm. The distance 'a' between the lower end of the sand-cutting trough and the side wall of the drainage ditch is 5 cm; the distance 'b' between the upper end of the sand-cutting trough and the side wall of the drainage ditch is 15-20 cm; the distance 'c' between the upper edge of the sand-cutting trough and the upper edge of the drainage ditch is 5 cm; the height 'd' of the upper half of the sand-cutting trough is 15-20 cm; the height 'e' of the middle half is 15-20 cm; and the height 'f' of the lower half is 5-10 cm. The angle 'x' at the bend of the sand-cutting trough is 30°-60°.
[0020] To ensure the structural stability of the sand interception trough, stainless steel fixing bolts and nuts are used to fix the sand interception trough to the side wall of the H-shaped drainage ditch, with the bolt plane spacing L being 30-60cm.
[0021] During the backwashing and drainage process, the filter media in the filter tank flows with the water flow and first passes through the sand interception trough. The sand filter media in the water flow enters the sand interception trough from above and sinks to the bottom of the sand interception trough under the action of gravity. It then returns to the filter tank through the sand discharge hole, thus avoiding being washed into the drainage ditch by the water flow.
[0022] This invention relates to a device for reducing filter media loss in filter beds. It primarily relies on a sand-catching trough to intercept sand. This trough is wider at the top and narrower at the bottom. During backwashing and drainage, fine filter media particles flow with the water and enter the upper part of the trough. The flow velocity decreases thereafter, causing the particles to settle to the bottom and flow back into the sand layer through the lower gaps. This device ensures that filter media is not lost with the backwash water into the drainage ditch, reducing the need for replenishing filter media during long-term operation, ensuring stable filtration performance, and reducing the operating costs of the water plant's filter system. The device is installed on the side wall of the drainage ditch using stainless steel bolts, allowing for manual installation at any time. The equipment is simple, easy to operate, and reliably effective.
[0023] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the concept and principles of this utility model should be included within the scope of protection of this utility model.
Claims
1. A device for reducing filter media loss in a filter bed, characterized in that, The device includes a sand-cutting trough and a fixing device. The sand-cutting trough is wider at the top and narrower at the bottom, and is shaped like a funnel with a sand discharge hole at the bottom. The sand-cutting trough is installed on the side wall of the H-shaped drainage channel of the filter pool near the filter media via the fixing device.
2. The device for reducing filter media loss in a filter bed according to claim 1, characterized in that, The fixing device includes fixing bolts and fixing nuts.
3. The device for reducing filter media loss in a filter bed according to claim 1, characterized in that, The sand-cutting trough is made of stainless steel with a wall thickness of 1-3 mm.
4. The device for reducing filter media loss in a filter bed according to claim 1, characterized in that, The distance 'a' between the lower end of the sand interception trough and the side wall of the drainage ditch is 5-8 cm.
5. The apparatus for reducing filter media loss in a filter bed according to claim 1, characterized in that, The distance b between the upper end of the sand interception trough and the side wall of the drainage ditch is 15-20cm.
6. The apparatus for reducing filter media loss in a filter bed according to claim 1, characterized in that, The distance c between the upper edge of the sand interception trough and the upper edge of the drainage ditch is 5-8cm.
7. The apparatus for reducing filter media loss in a filter bed according to claim 1, characterized in that, The sand interception trough is divided into three sections: upper, middle and lower. The height d of the upper section is 15-20cm, the height e of the middle section is 15-20cm, and the height f of the lower section is 5-10cm.
8. The apparatus for reducing filter media loss in a filter bed according to claim 1, characterized in that, The angle x at the bend between the middle and lower half of the sand interception groove is 30°-60°.
9. The apparatus for reducing filter media loss in a filter bed according to claim 1, characterized in that, The sand interception trough is fixed to the side wall of the H-shaped drainage ditch using stainless steel fixing bolts and nuts, with the bolt plane spacing L being 30-60cm.