Deep bed denitrification filter tank

Abstract

The utility model discloses a deep bed denitrification filter which comprises a filter body, a filter bed filled in the filter body and a backwashing pipeline, the filter bed comprises a lower supporting layer, a microbial filler layer positioned above the lower supporting layer, an upper supporting layer positioned above the microbial filler layer and a filter material filling layer positioned above the upper supporting layer; the backwash pipeline comprises a lower-layer backwash pipe laid below the lower supporting layer, an upper-layer backwash pipe laid below the upper supporting layer and a water supply pipe used for conveying backwash water, the water supply pipe is divided into two paths, one path is connected with the lower-layer backwash pipe, and the other path is connected with the upper-layer backwash pipe; and switch valves are mounted on the two water supply pipes. According to the utility model, the backwashing effect can be effectively improved, the backwashing frequency of an area where microorganisms are located is reduced, and the influence of backwashing on microbial populations is reduced.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, and in particular to a deep bed denitrification filter. Background Technology

[0002] The denitrification deep bed filter is a downflow packed bed post-anoxic denitrification filter, consisting of the filter body, filter media, and backwashing system. Water enters from the top and is distributed through channels. During operation, the filter allows suspended solids in the water to penetrate to the surface of the filter bed and into the interior of the filter media, achieving effective retention of solids throughout the entire filter depth. Because the denitrification filter retains a large amount of suspended solids and impurities during operation, these impurities gradually accumulate in the filter layer, leading to a decrease in filter porosity and filtration efficiency. Therefore, regular backwashing is necessary.

[0003] Existing backwashing methods involve spraying high-pressure water or air upwards from the bottom of the filter bed. However, due to the considerable depth of the filter bed, and the fact that impurities are mainly concentrated in the upper layers, high water or air pressure is required during backwashing, and a considerable amount of time is needed to achieve a satisfactory backwashing effect. This method is ineffective at cleaning the upper layers of the filter bed, and the frequent, prolonged high-pressure washing can negatively impact the microbial community within the filter bed. Utility Model Content

[0004] To address the problem that existing backwashing technologies in deep bed denitrification filters are ineffective at removing impurities from the filter media sand layer and have low backwashing efficiency, this invention proposes a backwashing denitrification deep bed filter.

[0005] This utility model proposes a backwashing denitrification deep bed filter, comprising: a filter body, a filter bed filled within the filter body, and backwashing pipelines, wherein:

[0006] The filter bed includes a lower support layer, a microbial packing layer above the lower support layer, an upper support layer above the microbial packing layer, and a filter media packing layer above the upper support layer.

[0007] The backwash pipeline includes a lower backwash pipe laid below the lower support layer, an upper backwash pipe laid below the upper support layer, and a water supply pipe for conveying backwash water. The water supply pipe is divided into two lines, one of which is connected to the lower backwash pipe and the other is connected to the upper backwash pipe. Both water supply pipes are equipped with switch valves.

[0008] Preferably, a first guide rail is installed on one side of the top of the filter body, and a second guide rail parallel to the first guide rail is installed on the opposite side of the filter body; a crossbeam spanning the filter body and slidably assembled with the first and second guide rails at both ends is provided above the filter body, and a drive mechanism for driving the crossbeam to move on the first and second guide rails is provided; the crossbeam is provided with a plurality of rods spaced apart along its length, all of which are vertically arranged and their lower ends are inserted into the filter media filling layer.

[0009] Preferably, the first guide rail is provided with a first rack on the side near the second guide rail, and the second guide rail is provided with a second rack opposite to the first rack on the side near the first guide rail; the drive mechanism includes a first motor, a second motor, a first gear mounted on the output shaft of the first motor, and a first rack mounted on the second motor. The first motor and the second motor are respectively mounted at both ends of the crossbeam, and the first gear meshes with the first rack, and the second gear meshes with the second rack.

[0010] Preferably, the member includes a lower segment and an upper segment. The lower segment has a rhomboid cross-sectional shape, and the length of its longest diagonal is in the same direction as the movement direction of the crossbeam.

[0011] Preferably, the rod is a cylindrical rod, and a third motor is connected to the top of the rod. The third motor is mounted on the crossbeam.

[0012] Preferably, the filler in the microbial packing layer is a porous biological packing ball.

[0013] Preferably, the fillers in both the upper and lower support layers are pebbles and / or gravel.

[0014] Preferably, a filter plate is provided above the microbial packing layer, and an upper backwash pipe is laid on the filter plate.

[0015] In this invention, the microbial packing layer serves as the biofilm medium for the microbial community to inhabit, while the filter media layer acts as the filtration medium to trap suspended solids. During operation, when excessive impurities trapped by the filter media layer reduce its porosity and filtration efficiency, the upper backwash pipe backwashes the filter media layer. This reverse water flow causes the filter layer to expand, and the filter media particles collide and rub against each other, removing trapped impurities and restoring the filter media to a clean state, ensuring the normal operation of the deep-bed denitrification filter. When the biofilm in the microbial packing layer ages, the lower backwash pipe flushes the entire filter bed to promote biofilm renewal. This structural design effectively improves the backwashing effect while reducing the number of backwashing cycles in the microbial area, thus minimizing the impact of backwashing on the microbial population. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a deep bed denitrification filter proposed in this utility model. Detailed Implementation

[0017] The specific embodiments of this utility model are described in detail below with reference to the accompanying drawings.

[0018] Reference Figure 1 The present invention proposes a backwashing denitrification deep bed filter, comprising: a filter body 1, a filter bed 2 filled within the filter body 1, and a backwashing pipeline 3, wherein:

[0019] The filter bed 2 comprises a lower support layer 21, a microbial packing layer 22 above the lower support layer 21, an upper support layer 23 above the microbial packing layer 22, and a filter media packing layer 24 above the upper support layer 23. Specifically: the packing material in the microbial packing layer 22 is porous biological packing balls, which utilize the high specific surface area and porosity of the porous biological packing balls to provide sufficient surface for microbial attachment and growth, promoting the formation and stability of the biofilm; the packing material in the filter media packing layer 24 is one or more of anthracite, quartz sand, and garnet; the packing material in both the upper support layer 23 and the lower support layer 21 is pebbles and / or gravel. This ensures that backwash water or air rises evenly, avoiding excessive local pressure that could cause filter media layer disorder, and also preventing the loss of fine particulate filter media during backwashing.

[0020] The backwash pipeline 3 includes a lower backwash pipe 31 laid below the lower support layer 21, an upper backwash pipe 32 laid below the upper support layer 23, and a water supply pipe for conveying backwash water. The water supply pipe is divided into two lines, one of which is connected to the lower backwash pipe 31 and the other is connected to the upper backwash pipe 32. Both water supply pipes are equipped with switch valves.

[0021] During operation, when excessive impurities are trapped in the filter media filling layer 24, leading to a decrease in filter layer porosity and a drop in filtration efficiency, the upper backwash pipe 32 backwashes the filter media filling layer 24. This backwashes the filter layer by causing it to expand through reverse water flow, and the filter media particles collide and rub against each other, removing trapped impurities and restoring the filter media to a clean state, thus ensuring the normal operation of the deep bed denitrification filter. When the biofilm in the microbial packing layer 22 ages, the lower backwash pipe 31 flushes the entire filter bed 2 to promote biofilm renewal.

[0022] In a further embodiment, a first guide rail is installed on one side of the filter body 1, and a second guide rail parallel to the first guide rail is installed on the opposite side of the filter body 1. A first rack is provided on the side of the first guide rail closest to the second guide rail, and a second rack is provided on the side of the second guide rail closest to the first guide rail, opposite to the first rack. Above the filter body 1, a crossbeam 4 spans the filter body 1 and is slidably fitted at both ends to the first and second guide rails, respectively. A drive mechanism 5 is mounted on the crossbeam 4. The drive mechanism 5 includes a first motor, a second motor, a first gear mounted on the output shaft of the first motor, and a first rack mounted on the second motor. The first motor and the second motor are respectively mounted at both ends of the crossbeam 4, and the first gear meshes with the first rack, and the second gear meshes with the second rack. The crossbeam 4 has multiple rods 6 spaced along its length, all of which are vertically arranged and their lower ends are inserted into the filter media filling layer 24. During the backwashing process of the filter media filling layer 24 by the upper backwash pipe 32, if the filter media filling layer 24 becomes compacted and the backwashing effect is not obvious, the drive mechanism 5 drives the crossbeam 4 to move the rod 6 from one end of the filter tank to the other end, so as to use the rod 6 to break up the compacted filter media and increase the backwashing effect.

[0023] Furthermore, the rod 6 includes a lower rod section and an upper rod section. The lower rod section has a rhomboid cross-sectional shape, and the length of its longest diagonal is aligned with the moving direction of the crossbeam 4. This reduces forward resistance and allows the broken filter media to quickly converge at the rear end of the rod 6. Alternatively, the rod 6 can be configured as a cylindrical rod, with a third motor 7 connected to its top. The third motor 7 is mounted on the crossbeam 4. As the crossbeam 4 moves the rod 6 forward, the third motor 7 drives the rod 6 to rotate. This reduces forward resistance and utilizes the friction between the rod 6 and the filter media to enhance the cleaning effect on the filter media surface.

[0024] In a further embodiment, a filter plate 8 is provided above the microbial packing layer 22, and an upper backwash pipe 32 is laid on the filter plate 8. This way, on the one hand, the filter plate 8 can provide support for the upper backwash pipe, and on the other hand, it can prevent cross-layering between the microbial packing layer 22 and the filter media packing layer 24 during backwashing.

[0025] As can be seen from the above, this utility model can effectively improve the backwashing effect, while reducing the number of backwashings in the area where microorganisms are located, and reducing the impact of backwashing on the microbial population.

[0026] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A deep-bed denitrification filter, characterized in that, include: The filter body (1), the filter bed (2) filled inside the filter body (1), and the backwashing pipeline (3) are as follows: The filter bed (2) includes a lower support layer (21), a microbial packing layer (22) above the lower support layer (21), an upper support layer (23) above the microbial packing layer (22), and a filter media packing layer (24) above the upper support layer (23). The backwash pipeline (3) includes a lower backwash pipe (31) laid below the lower support layer (21), an upper backwash pipe (32) laid below the upper support layer (23), and a water supply pipe for conveying backwash water. The water supply pipe is divided into two lines, one of which is connected to the lower backwash pipe (31) and the other is connected to the upper backwash pipe (32). Both water supply pipes are equipped with switch valves.

2. The deep-bed denitrification filter according to claim 1, characterized in that, A first guide rail is installed on one side of the top of the filter body (1), and a second guide rail parallel to the first guide rail is installed on the opposite side of the filter body (1). A crossbeam (4) spanning the filter body (1) and slidably assembled with the first guide rail and the second guide rail at both ends is provided above the filter body (1), and a drive mechanism (5) for driving the crossbeam (4) to move on the first guide rail and the second guide rail is provided. Multiple rods (6) are provided on the crossbeam (4) at intervals along its length direction. All rods (6) are vertically arranged and their lower ends are inserted into the filter media filling layer (24).

3. The deep-bed denitrification filter according to claim 2, characterized in that, The first guide rail is provided with a first rack on the side near the second guide rail, and the second guide rail is provided with a second rack opposite to the first rack on the side near the first guide rail; the drive mechanism (5) includes a first motor, a second motor, a first gear mounted on the output shaft of the first motor, and a first rack mounted on the second motor. The first motor and the second motor are respectively mounted at both ends of the crossbeam (4), and the first gear meshes with the first rack, and the second gear meshes with the second rack.

4. The deep-bed denitrification filter according to claim 2, characterized in that, The member (6) includes a lower section and an upper section. The cross-sectional shape of the lower section is rhomboid, and the length of its longest diagonal is in the same direction as the movement direction of the crossbeam (4).

5. The deep-bed denitrification filter according to claim 2, characterized in that, The rod (6) is a cylindrical rod, and the top of the rod (6) is connected to a third motor (7), which is installed on the crossbeam (4).

6. The deep-bed denitrification filter according to claim 1, characterized in that, The packing material in the microbial packing layer (22) is a porous biological packing ball.

7. The deep-bed denitrification filter according to claim 1, characterized in that, The fillers in the upper support layer (23) and the lower support layer (21) are pebbles and / or gravel.

8. The deep-bed denitrification filter according to any one of claims 1-7, characterized in that, A filter plate (8) is provided above the microbial packing layer (22), and an upper backwash pipe (32) is laid on the filter plate (8).

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