Fabricated biological filter adopting filter box

Abstract

The utility model discloses an assembled biological filter adopting a filter box and belongs to the field of biological filters. Comprising a biological filter peripheral wall body, a bottom plate, a water inlet pipe, a backwashing gas inlet pipe, a backwashing water inlet pipe, a filter head, a filter plate, a bracket, a filter box, a filter box top box, a water inlet and outlet weir, a water inlet channel, a backwashing gas branch pipe and a backwashing water branch pipe, the filter plate is placed on the bracket and is provided with a filter head; a plurality of filter boxes are placed on the filter plate assembly and are arranged in a one-layer or multi-layer array, the filter plates are densely distributed on the bottommost layer, and a filter box top box is adopted on the uppermost layer; a water inlet pipe, a backwashing air inlet pipe and a backwashing water inlet pipe are arranged on the side surface of the lower part of the tank body; a backwashing gas branch pipe and a backwashing water branch pipe are arranged below the filter plate in the tank body; the water inlet pipe is correspondingly positioned below the filter plate; the bottom of the water inlet channel is communicated with the lower part of the filter plate of the tank body through a water inlet pipe. Filter materials are independently packed, head loss during backwashing is reduced, and operation and maintenance are convenient and simple.

Description

Technical Field

[0001] The utility model belongs to the field of biological filter tanks, and in particular relates to an assembled biological filter tank. Background Art

[0002] Biological Aerated Filter (BAF) is a water purification technology that has been widely used in China since the 1990s. It belongs to the category of biofilm and is used in sewage biological treatment and micro-polluted water source pretreatment. Its basic principle is that during the water purification process, pollutants undergo complex biochemical processes such as adsorption, filtration, mineralization, transformation and oxidation with the microbial film on the filler in the BAF, so as to separate pollutants from the water body and achieve the purpose of water purification. It has been widely used in various sewage treatment projects such as sewage treatment, micro-polluted source water pretreatment, sewage deep treatment and reuse treatment.

[0003] The structure of the biofilter is divided into: buffer water distribution area, filter plate, support layer, filter material layer, outlet area, etc. The supporting system also includes the aeration system in the pool, water inlet system, water outlet system, air blowing system, compressed air system, air-water backwash system, backwash drainage system, power distribution and automatic control system.

[0004] However, existing biological aerated filters have the following defects:

[0005] The pool uses a complex civil engineering structure, and the pool structure needs to be poured twice, which has a long maintenance cycle, thus increasing the construction period. The construction quality requirements are relatively high, the quality is uneven, and quality accidents occur frequently.

[0006] It is inconvenient to inspect and repair the equipment in the pool after operation. When maintenance is required in the pool, some filter tanks do not have manholes and cannot be repaired. The filter tanks with manholes have a narrow lower environment during maintenance, which is a confined space and poses a safety hazard. There is a lot of sludge at the bottom of the pool and the working environment is poor. The content of harmful gases is high, and ventilation and oxygen supplementation are required in advance during maintenance work.

[0007] The water and air distribution on the pool bottom is uneven and cannot be flexibly adjusted according to working conditions.

[0008] The filter media is not level during operation, and local filter media spraying occurs during backwashing, which results in partial compaction or short-circuiting of the filter tank, thereby reducing the treatment effect of the filter tank and increasing operating costs.

[0009] Existing filter tanks cannot accommodate the superposition or combined use of multiple filter media.

[0010] The existing filter tank structure has a heavy backwash load and frequent backwashing, resulting in reduced water production and increased operating costs.

[0011] In the discussion on the analysis and treatment of uneven aeration causes in aerated biological filters in article number 2096-3548(2023)02-0028-03, as the operating time of aerated biological filters increases, problems such as serious blockage of filter media, serious damage to aerator branch pipes, uneven aeration, and increased load on aeration fans will gradually emerge.

[0012] Limited by existing technical conditions, there are filter beams and filter columns in the bottom structure of the pool, which are used as the support system for pouring the filter plate layer. In order to ensure the accurate position in the pool, secondary pouring is required. The construction quality requirements are high and the difficulty is great. Limited by the existing pool structure, the bottom space of the biological filter is 600-1000mm, and it is difficult for maintenance workers to enter the bottom of the pool for maintenance. The content of harmful gases in the pool is high, the working environment is poor, and there are great safety hazards. In the existing pool structure, the water and air distribution system at the bottom of the pool is uneven, resulting in uneven filter material layer above the filter plate during operation or backwashing, and large pits will appear in places with large gas volume. In severe cases, the pebble layer will return. In the existing biofilter structure, the thickness of the filter material layer is 3-4 meters, and the head loss of the filter material layer is large. The backwash load is large, and the backwash cost is large during operation. Limited by the existing pool structure, there is no physical separation in the filter material layer, and it is difficult to achieve a multi-layer combination of the filter material layer. Utility Model Content

[0013] The purpose of the utility model is to overcome the shortcomings of the prior art and provide a new assembled biofilter. The assembled biofilter eliminates the need for secondary civil construction in the biofilter. It is constructed using assembled technology. The construction period is shortened. A filter layer in the form of a filter box is adopted, and different combinations of filter layers can be arranged in layers in the filter box. Two or more filter layers are arranged in the biofilter, such as quartz sand in the lower layer and volcanic rock biofilter in the upper layer, or volcanic rock biofilter in the lower layer and polymer filler in the upper layer; a combination of multiple filter materials can be achieved, so that the biofilter can play different functions of biofilm removal of pollutants and deep filtration. Constrained by the filter box, the filter materials are layered and flat. The filter materials are packed independently to reduce the head loss during backwashing. Reduce the backwashing intensity and save energy. After the equipment in the biofilter is assembled, the operation and maintenance are convenient and simple. When repairing the equipment in the pool, the corresponding filter box that needs to be repaired can be lifted out of the biofilter for separate repair, which is convenient and quick.

[0014] In order to achieve the above-mentioned purpose, the utility model discloses an assembled biofilter, which is an integrated multifunctional biofilter, comprising walls around the biofilter, a bottom plate, an inlet pipe (1), a manhole (2), a backwash air inlet pipe (3), a backwash water inlet pipe (4), a filter head (5), a filter plate (6), a bracket (7), a filter box (8), a filter box top box (9), a water outlet weir (10), a water inlet weir (11), an inlet channel (12), a backwash air branch pipe (13), and a backwash water branch pipe (14); the surrounding walls and the bottom plate constitute a tank body, which can be made of a concrete structure or a carbon steel anti-corrosion box;

[0015] The support (7) is placed on the bottom plate of the tank body, and the filter plate (6) is placed on the support (7) so that there is a certain distance between the filter plate (6) and the bottom plate; the filter plate (6) is provided with holes, and the filter head (5) is matched and installed on the corresponding holes; the filter plate (6) is equipped with a plurality of filter boxes (8), and the filter material is laid flat in the filter box (8). The plurality of filter boxes (8) are arranged in a single layer or multiple layers, and the bottom layer is closely arranged and covered with filter plates (6), and multiple layers of filter boxes (8) are arranged upward according to the size of the tank body space; the top layer adopts a filter box top box (9);

[0016] A water outlet weir (10) is provided on one side of the upper part of the pool body; a water inlet pipe (1), a manhole (2), a backwash air inlet pipe (3), and a backwash water inlet pipe (4) are provided on the side of the lower part of the pool body; a backwash air branch pipe (13) and a backwash water branch pipe (14) are provided below the filter plate (6) in the pool body, the backwash air branch pipe (13) is connected to the backwash air inlet pipe (3), and the backwash water branch pipe (14) is connected to the backwash water inlet pipe (4). The water inlet pipe (1) is correspondingly located below the filter plate (6). The water inlet channel (12) is located outside the pool body, and the bottom of the water inlet channel (12) is connected to the bottom of the filter plate (6) of the pool body through the water inlet pipe (1).

[0017] A water inlet weir (12) is arranged in the water inlet channel (12).

[0018] This utility model technology adopts assembled equipment technology, and the facilities in the biological filter tank are all assembled and installed, further:

[0019] The water inlet pipe (1) is installed below the water inlet channel (12), and sewage enters the biological filter tank through the water inlet pipe (1).

[0020] The manhole (2) is installed at the lower part of the bottom of the pool wall and is used as an inspection hole.

[0021] The backwash air inlet pipe (3) is installed at the bottom of the filter tank and connected to the backwash air branch pipe (13) in the tank. When the biofilter tank is backwashed, air is blown into the pipe to scrub the filter material in the filter box and renew the biofilm to achieve the purpose of backwashing.

[0022] The backwash water inlet pipe (4) is installed at the bottom of the filter tank and connected to the backwash water branch pipe (14) in the tank. When the biofilter tank is backwashed, clean water is introduced through this pipe to clean the filter material in the filter box and renew the biofilm to achieve the purpose of backwashing.

[0023] The filter head (5) is installed on the filter plate (6) and fixed by a threaded pipe (S3) and a nut sleeve (S4). The number of filter heads installed is adjusted according to the water inflow of the biofilter. The filter head has the function of evenly distributing water and air. The filter head mainly includes a filter rod. The upper part of the filter rod is provided with an aeration hole and an annular gap, and the lower part is provided with a water inlet and air inlet hole and a water inlet and air inlet slit.

[0024] In an aerated biological filter tank that requires an aeration function, the filter head can be aerated through an aeration slit (S1). When water is inlet, water is distributed upward through the annular slit (S2) on the filter head. When backwashing, water and air are evenly distributed through the water inlet and air inlet holes (S6) and the water inlet and air inlet slits (S7) on the filter rod (S2).

[0025] The filter plate (6) is mounted on the bracket (7), and the filter plate and the bracket are connected by full welding or riveting, especially riveting, which is convenient for replacement and adjustment of the number of filter heads. The filter plate structure adopts the form of corrugated plate to increase the bearing capacity of the filter plate.

[0026] The support (7) is installed at the bottom of the biofilter and is composed of upright posts and vertical and horizontal frames. The filter plates are embedded in the spaces formed by the vertical and horizontal frames.

[0027] The filter box (8) is installed in the biofilter tank, installed above the filter plate (6), and supported by the filter plate (6) and the bracket (7). The filter box (8) is a grid-shaped box with an upper opening, which is composed of a rectangular frame and a corrugated board with holes, and the corrugated board is fixed to the inner sides and bottom of the frame. Holes or fine gaps are opened in the corrugated board, and sewage can only flow out through the holes or fine gaps to prevent the loss of biological filter materials; biological filter materials (commonly volcanic rocks, quartz sand, activated carbon, etc.) can be filled in the filter box, and the biological filter materials are laid in the same or different layers.

[0028] The filter box top box (9) is installed on the uppermost layer of the filter box (8) and is a box body with a cover. The remaining structure of the filter box top box (9) is the same as that of the filter box (8).

[0029] The outlet channel (10) is located on the right side of the biological filter tank, and sewage is discharged from the outlet channel (10) after being treated by the filter box (8) and the filter box top box (9).

[0030] The water inlet channel 12 is located on the right side of the biological filter outlet channel (10), and sewage flows into the water inlet channel (12) from the upstream and flows into the biological filter through the water inlet pipe (1).

[0031] Workflow: Sewage enters the bottom of the biofilter from the upstream through the water inlet channel (12) and the water inlet pipe (1), and enters the upper filter box through the filter head (5) installed on the filter plate (6). The sewage is fully in contact with the filter material in the filter box. Different biological filter materials are selected according to the characteristics of the treated water. For example, when encountering difficult-to-treat industrial water, activated carbon and volcanic rock materials are preferred. The high porosity and high specific surface area are used to increase the biomass of the biofilm. The impact resistance of the biofilter is improved. The filter material forms a stable and highly active biofilm on its surface. It is suitable for the growth and reproduction of various microorganisms, especially nitrifying bacteria and denitrifying bacteria, thereby achieving sewage purification.

[0032] The utility model provides a device for an assembled biofilter, which reduces the tediousness of civil construction. The assembled structure in the pool makes installation faster and the construction precision is high. It is convenient to repair and maintain during operation, which reduces the safety risk. Compared with the prior art, the beneficial effect of the utility model is that the biofilter is constructed in an assembled form, which reduces the civil structure in the pool. Modular equipment is used in the pool, which is convenient for construction. The installation speed is fast. The modular design of the filter box allows the filter material to be installed in combination. One or more biological filter materials can be selected. There will be no fault or mixed layer phenomenon. Through the assembled design of each device in the pool, the biofilter is easy to maintain after operation. The difficulty of maintenance is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the assembled biological structure of the utility model.

[0034] A water inlet pipe (1), a manhole (2), a backwash air inlet pipe (3), a backwash water inlet pipe (4), a filter head (5), a filter plate (6), a bracket (7), a filter box (8), a filter box top box (9), a water outlet weir (10), a water inlet weir (11), a water inlet channel (12), a backwash air branch pipe (13), and a backwash tank washing water branch pipe (14).

[0035] Figure 2 This is another side view of the filter tank;

[0036] Figure 3 Schematic diagram of the filter head structure.

[0037] Figure 4 Schematic diagram of filter plate structure.

[0038] Figure 5 A schematic diagram of the support structure.

[0039] Figure 6 Schematic diagram of filter box structure.

[0040] Figure 7 Schematic diagram of the filter box top box structure.

[0041] Inlet pipe (1), manhole (2), backwash air inlet pipe (3), backwash water inlet pipe (4), filter head (5), filter plate (6), bracket (7), filter box (8), filter box top box (9), outlet weir (10), inlet weir (11), inlet channel (12), backwash air branch pipe (13), backwash tank washing water branch pipe (14);

[0042] S1- aeration slit, S2- annular slit, S4- nut sleeve, S3- threaded pipe, S5- filter rod, S6- water inlet and air inlet hole, S7- water inlet and air inlet strip slit. DETAILED DESCRIPTION

[0043] The present invention is further described below in conjunction with specific embodiments, but the present invention is not limited to the following embodiments.

[0044] The schematic diagram of the assembled biological structure of the utility model is shown in Figure 1 .

[0045] The sewage enters the inlet channel, enters the bottom of the filter tank through the inlet channel 11 and the inlet pipe 1, and enters the filter box through the filter plate and filter head at the bottom of the tank. The filter box contains biological filter material. During operation, the biological filter material is pre-filmed with sludge to form a biofilm with nitrification or denitrification functions. After the sewage is treated by the filter box with biological filter material and biofilm, it flows out of the tank through the outlet channel 10.

[0046] The biological filter needs to be backwashed within the operating cycle of 12-72 hours (the blower and backwash water pump required for backwashing are auxiliary supporting facilities and are not within the scope of the present invention).

[0047] The backwash procedure is as follows:

[0048] (S1) Air washing

[0049] Close the filter tank water inlet pipe 1 → blow air through the filter tank backwash air inlet pipe 3 and the blower → perform air washing for 3-5 minutes.

[0050] (S2) Simultaneous backwashing with air and water

[0051] While performing air washing, open the filter tank backwash water inlet pipe 4 → start the water pump in the clean water tank → perform air-water combined backwash for 8-10 minutes.

[0052] (S3) Water rinsing

[0053] Stop aeration → close the filter backwash inlet pipe 3 → stop air washing, and rinse with water alone for 5-10 minutes before stopping.

[0054] After backwashing is completed, the system can return to the water production stage.

[0055] Example 2

[0056] Three groups of biological filter media are set in the biological filter experimental device. According to the direction of water flow, they are quartz sand group, volcanic rock filter media group and activated carbon group. They can be increased or decreased according to needs. The ratio of filter materials is volcanic rock 3-5mm, quartz sand particle size 2-4mm, activated carbon 2-4mm, and the order of filter media is volcanic rock-quartz sand-activated carbon. The filter media thickness is 100-150mm, and the filter layer is placed in a direction perpendicular to the water flow direction. Each biological filter media is installed separately in the filter box. The structural dimensions of the biological filter (length × width × height) = 2.0m × 0.5m × 1.0m, the effective liquid level height is 0.5m, and the effluent is discharged externally;

[0057] Among them, the experimental temperature was room temperature, and the inoculated sludge of the biological filter unit was collected from aerobic sludge with similar water quality in the sewage treatment plant. After about 30 days of debugging, the filter film was well formed, the treatment facilities operated basically stably, the average COD removal rate of the effluent reached 30.84%, the average removal rate was 25%-30%, and the average ammonia nitrogen removal rate was 15%-18%.

[0058] Based on the above experimental results, this combination of filter materials has a better effect than a single component. This experiment can be used as a reference when applied to actual cases.

Claims

1. An assembled biological filter using a filter box, characterized in that: The filter material is filled in a filter box, the filter material is laid flat in the filter box (8), and a plurality of filter boxes (8) are arranged in a single layer or multiple layers in an array in a corresponding biological filter tank; The invention discloses an integrated multifunctional biological filter, comprising walls surrounding the biological filter, a bottom plate, an inlet pipe (1), a manhole (2), a backwash air inlet pipe (3), a backwash water inlet pipe (4), a filter head (5), a filter plate (6), a bracket (7), a filter box (8), a filter box top box (9), a water outlet weir (10), a water inlet weir (11), an inlet channel (12), a backwash air branch pipe (13), and a backwash water branch pipe (14); the surrounding walls and the bottom plate constitute a tank body, which adopts a concrete structure or a carbon steel anti-corrosion box body; The support (7) is placed on the bottom plate of the tank body, and the filter plate (6) is placed on the support (7) so that there is a distance between the filter plate (6) and the bottom plate; the filter plate (6) is provided with a hole, and a filter head (5) is matched and installed on the corresponding hole; the filter plate (6) is equipped with a plurality of filter boxes (8), and filter materials are laid flat in the filter boxes (8). The plurality of filter boxes (8) are arranged in a single layer or multiple layers, and the bottom layer is closely arranged and covered with filter plates (6), and multiple layers of filter boxes (8) are arranged upward according to the size of the tank body space; the top layer adopts a filter box top box (9); A water outlet weir (10) is provided on one side of the upper part of the pool body; a water inlet pipe (1), a manhole (2), a backwash air inlet pipe (3), and a backwash water inlet pipe (4) are provided on the side of the lower part of the pool body; a backwash air branch pipe (13) and a backwash water branch pipe (14) are provided below the filter plate (6) in the pool body, the backwash air branch pipe (13) is connected to the backwash air inlet pipe (3), and the backwash water branch pipe (14) is connected to the backwash water inlet pipe (4); the water inlet pipe (1) is correspondingly located below the filter plate (6); the water inlet channel (12) is located outside the pool body, and the bottom of the water inlet channel (12) is connected to the bottom of the filter plate (6) of the pool body through the water inlet pipe (1); A water inlet weir (11) is provided in the water inlet channel (12); The filter head (5) is installed on the filter plate (6) and fixed by a threaded pipe (S3) and a nut sleeve (S4). The number of filter heads installed is adjusted according to the water inflow of the biofilter. The filter head has the function of evenly distributing water and air. The filter head mainly comprises a filter rod. The upper part of the filter rod is provided with an aeration hole and an annular gap, and the lower part is provided with a water inlet and air inlet hole and a water inlet and air inlet slit. In an aerated biological filter tank that requires an aeration function, the filter head can be aerated through an aeration slit (S1), and water is distributed upward through the annular slit (S2) on the filter head during water intake. During backwashing, water and air are evenly distributed through the water inlet and air inlet holes (S6) and the water inlet and air inlet slits (S7) on the filter rod.

2. The assembled biofilter using a filter box according to claim 1, characterized in that: The water inlet pipe (1) is installed below the water inlet channel (12), and sewage enters the biofilter through the water inlet pipe (1); the manhole (2) is installed at the lower part of the bottom of the pool wall and is used as an inspection hole.

3. The assembled biofilter using a filter box according to claim 1, characterized in that: The backwash air inlet pipe (3) is installed at the bottom of the filter tank and connected to the backwash air branch pipe (13) in the tank. When the biological filter tank is backwashed, air is blown into the pipe to scrub the filter material in the filter box and renew the biofilm to achieve the purpose of backwashing. The backwash water inlet pipe (4) is installed at the bottom of the filter tank and connected to the backwash water branch pipe (14) in the tank. When the biological filter tank is backwashed, clean water is blown into the pipe to clean the filter material in the filter box and renew the biofilm to achieve the purpose of backwashing.

4. The assembled biofilter using a filter box according to claim 1, characterized in that: The filter plate (6) is mounted on a bracket (7), and the filter plate and the bracket are connected by full welding on all sides; the filter plate structure adopts a corrugated plate form to increase the bearing capacity of the filter plate; the bracket (7) is installed at the bottom of the biological filter tank, and is composed of columns and vertical and horizontal frames, and the filter plate is embedded in the space formed by the vertical and horizontal frames.

5. An assembled biofilter using a filter box according to any one of claims 1 to 4, characterized in that: The filter box (8) is installed in the biological filter tank, installed above the filter plate (6), and supported by the filter plate (6) and the bracket (7). The filter box (8) is a grid-shaped box with an upper opening, and is composed of a rectangular frame and a corrugated plate with holes. The corrugated plate is fixed to the inner sides and bottom of the frame. The corrugated plate is provided with holes or fine gaps, and sewage can only flow out through the holes or fine gaps, thereby preventing the loss of biological filter material. The filter box can be filled with biological filter material, and the biological filter material is laid flat in the same or different layers. The filter box top box (9) is installed on the uppermost layer of the filter box (8) and is a box body with a cover. The remaining structure of the filter box top box (9) is the same as that of the filter box (8).

6. The assembled biofilter using a filter box according to claim 1, characterized in that: The outlet weir (10) is located on the right side of the biological filter tank, and the sewage is discharged from the outlet weir (10) after being treated by the filter box (8) and the filter box top box (9); The water inlet channel (12) is located on the right side of the biological filter tank outlet weir (10), and sewage flows into the water inlet channel (12) from the upstream and flows into the biological filter tank through the water inlet pipe (1).

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