A V-type filter for sewage treatment
By using a sliding frame structure driven by heating wires and electromagnets in a V-shaped filter, the problem of reduced activity of denitrifying bacteria at low temperatures was solved, thereby improving wastewater treatment efficiency and reducing equipment costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JIANGSU YUANSHENGLIN ENVIRONMENTAL EQUIPMENT CO LTD
- Filing Date
- 2026-06-23
- Publication Date
- 2026-07-24
AI Technical Summary
In denitrifying V-type filters, the metabolic activity of denitrifying bacteria is significantly reduced under low temperature conditions, resulting in reduced nitrogen removal efficiency, excessive nitrogen content in effluent, and affecting wastewater treatment performance.
By installing heating wires and an electromagnet-driven sliding frame structure in the filter, the wastewater temperature can be rapidly increased and the flow channel can be regulated, enhancing the metabolic activity of denitrifying bacteria. Intermittent shaking prevents nitrogen adhesion, and combined with air-water backwashing technology, efficient denitrification is ensured.
Enhancing the metabolic activity of denitrifying bacteria under low-temperature conditions ensures wastewater treatment efficiency, reduces nitrogen adhesion and channel blockage, extends the working cycle of the filter, and reduces energy consumption and equipment costs.
Smart Images
Figure CN122444337A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of water pollution control technology, specifically to a V-type filter for wastewater treatment. Background Technology
[0002] V-type filters are a common type of rapid sand filter, named for their V-shaped inlet tank, and are also known as uniform particle filter tanks. V-type filters utilize a uniform quartz sand filter layer, combined with a backwashing technology that simultaneously uses air and water to backwash the surface of the water to be filtered. Air is distributed using an air cushion and a dedicated long-handled filter head for air and water distribution. This results in advantages such as high dirt-holding capacity of the filter layer, equal head filtration, good backwashing effect, and low filter media loss rate. Adding a biological filter layer to the V-type filter allows it to possess biological treatment capabilities alongside physical filtration, making it widely used in advanced wastewater treatment and reclaimed water reuse, and playing a significant role in water pollution control and treatment.
[0003] Currently, in denitrifying V-type filters, denitrifying bacteria attached to the biological packing material convert nitrates into nitrogen gas in an anaerobic environment, which is a common method for achieving wastewater denitrification.
[0004] However, the metabolic activity of denitrifying bacteria is significantly affected by water temperature. In winter or cold regions, the temperature of the living environment of denitrifying bacteria decreases when low-temperature wastewater is introduced into the filter, which in turn leads to a significant reduction in the metabolic activity of denitrifying bacteria and a marked slowdown in the reaction rate. This results in a significant reduction in denitrification efficiency, which can easily cause the nitrogen content in the effluent to exceed the standard, seriously affecting the water pollution control and treatment effect of wastewater. Summary of the Invention
[0005] The purpose of this invention is to provide a V-type filter for wastewater treatment to solve the problems mentioned above.
[0006] To achieve the above objectives, the present invention provides the following technical solution: A V-shaped filter for wastewater treatment includes multiple filter bodies. Each filter body is provided with an inlet tank, a biological filter layer, a quartz sand filter media layer, a support layer, a filter plate, and an outlet tank from top to bottom. Multiple long-handled filter heads are fixed on the filter plate. The biological filter layer includes an installation frame fixed in the filter body and a multi-layer sliding frame that is slidably disposed in the installation frame in the horizontal direction. Each layer of the sliding frame is divided into multiple channels by multiple partitions, and multiple biological packing materials are fixed in each channel. An iron block is fixedly installed on each layer of the sliding frame, and an electromagnet and a spring are installed on the mounting frame corresponding to each layer of the sliding frame; The partition is made of thermally conductive material and has a heating wire coil inside; The filter body is equipped with an inlet water temperature monitoring device; When the inlet water temperature monitoring device detects that the inlet water temperature is lower than the set threshold, it energizes the heating wire and simultaneously energizes the electromagnet, causing the multi-layered sliding frames to be misaligned, thus changing the water flow channel from a vertical straight path to a tortuous path.
[0007] As a preferred embodiment of the V-shaped filter for wastewater treatment described in this invention, the inlet trough has a V-shaped structure, and its side wall has water distribution holes located above the biological filter layer. The filter body has inlet holes located at the end of the inlet trough.
[0008] As a preferred embodiment of the V-shaped filter for sewage treatment described in this invention, each filter body is further provided with an inlet main channel, an inlet overflow weir, an inlet weir, and an inlet valve. An inlet valve is provided between the inlet main channel and the inlet overflow weir. Sewage enters the inlet overflow weir and the inlet weir in sequence through the inlet valve and then flows into the inlet tank through the inlet hole.
[0009] In a preferred embodiment of the V-shaped filter for wastewater treatment described in this invention, the inlet water temperature monitoring device is a temperature sensor installed inside the inlet hole.
[0010] As a preferred embodiment of the V-shaped filter for wastewater treatment according to the present invention, the biological packing includes a shell and a flexible fiber cloth fixedly connected inside the shell, and the shell has through holes.
[0011] As a preferred embodiment of the V-type filter for wastewater treatment described in this invention, the microorganisms attached to the biological packing are denitrifying bacteria, which are used to convert nitrates into nitrogen gas in an anaerobic environment to reduce the nitrogen content in wastewater.
[0012] As a preferred embodiment of the V-shaped filter for wastewater treatment described in this invention, the electromagnet is intermittently switched on and off. When the electromagnet is energized, it attracts the iron block and causes the sliding frame to shift. When the power is off, the spring drives the sliding frame to reset, thereby realizing the reciprocating swaying of the sliding frame to reduce the adhesion of nitrogen gas produced by denitrifying bacteria.
[0013] As a preferred embodiment of the V-shaped filter for wastewater treatment described in this invention, a water storage tank is provided on one side of the filter body, and a backwashing component is provided between the water storage tank and the effluent tank. The backwashing component is used to introduce backwashing water or backwashing air into the filter body.
[0014] As a preferred embodiment of the V-type filter for wastewater treatment according to the present invention, the backwashing assembly includes a backwashing air pipe, a backwashing water pipe, and corresponding first valve, second valve, and third valve. The backwashing air pipe is used to introduce backwashing air into the effluent tank, and the backwashing water pipe is used to introduce backwashing water into the effluent tank. The first valve is disposed on the backwashing air pipe, and the second and third valves are disposed on the backwashing water pipe.
[0015] As a preferred embodiment of the V-shaped filter for wastewater treatment described in this invention, the filter body is provided with a backwashing trough with an inclined bottom surface, and a main drainage channel for discharging backwashing wastewater is provided at the bottom end of the backwashing trough inside the filter body, and a drainage valve is provided between the backwashing trough and the main drainage channel.
[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. When the influent temperature is lower than a set threshold, the present invention energizes the heating wire to heat the wastewater, and simultaneously energizes the electromagnet to cause the multi-layer sliding frames to stagger, changing the water flow channel from a vertical straight path to a tortuous path. On the one hand, the heating wire directly heats the wastewater flowing through the baffle, which can quickly raise the water temperature. This helps to raise the water temperature of the subsequent denitrifying bacteria, thereby helping to improve the metabolic activity of the denitrifying bacteria. On the other hand, the staggered arrangement of the multi-layer sliding frames creates a tortuous flow channel between the baffles, increasing the contact time between the wastewater and the heating baffle, ensuring that the wastewater temperature is fully raised to a suitable range. At the same time, it prolongs the contact time between the wastewater and the denitrifying bacteria on the biological packing after the water temperature rises, compensating for the problem of reduced nitrogen removal efficiency caused by insufficient microbial activity under low temperature conditions. This ensures that the filter can still stably and efficiently remove nitrogen from the wastewater when the influent temperature is low, significantly improving the adaptability and operational stability of the filter in cold regions, and ensuring the effectiveness of water pollution control and treatment for wastewater.
[0017] 2. During the process of heating wastewater to enhance the metabolic activity of denitrifying bacteria, the electromagnet is intermittently switched on and off. When the electromagnet is energized, it attracts iron blocks and causes the sliding frame to shift. When the power is off, the spring drives the sliding frame to reset, realizing the reciprocating swaying of the sliding frame. This effectively shakes off nitrogen bubbles attached to the biological packing material, reduces the accumulation of nitrogen on the surface of the biological packing material, avoids the reduction of effective biological contact area and blockage of water passage caused by nitrogen adhesion, thereby reducing the nitrogen removal frequency, extending the working cycle of the filter, and improving the overall operating efficiency of the filter.
[0018] 3. When the wastewater temperature is higher than the set threshold, the wastewater temperature is at the suitable temperature required for the formation and metabolism of denitrifying bacteria. At this time, the electromagnet is de-energized, the multi-layer sliding frame remains vertically aligned, the water flow channel is a short vertical path, and the wastewater can quickly pass through the biological filter layer, making full use of the high metabolic activity of denitrifying bacteria at the suitable temperature to achieve efficient denitrification, ensuring the water pollution control and treatment effect of wastewater, and ensuring the treatment flux and wastewater treatment efficiency of the filter.
[0019] 4. Driven by electromagnets and springs, the sliding frame can achieve both misalignment maintenance under low-temperature conditions and intermittent dynamic reciprocating oscillation. One set of drive mechanism simultaneously realizes the dual functions of flow channel adjustment and nitrogen adsorption prevention. It has a compact structure, simple control, and no need to add an additional shaking device, which reduces equipment cost and failure rate.
[0020] 5. During backwashing, the electromagnet is de-energized, causing the sliding frame to return to its vertical alignment. The through groove is open from top to bottom, which facilitates the uniform flow of backwash water and backwash air through the biological filter layer from bottom to top. At the same time, it facilitates the floating of intercepted materials and detached biofilm with the backwash wastewater and their discharge through the backwash tank and the main drainage channel, thereby improving backwashing efficiency and reducing backwash water consumption and energy consumption.
[0021] 6. By placing the heating wire disc inside the heat-conducting partition, this invention increases the direct contact area between the heating element and the sewage, resulting in a shorter heat transfer path and less heat loss. Compared with external heating methods, it consumes less energy and provides more uniform heating. At the same time, the shell of the biological packing is made of heat-insulating material, which can effectively prevent the heat from the partition from being directly conducted to the inside of the biological packing, thereby achieving the purpose of heat insulation protection for the microorganisms attached to the inside of the biological packing. This ensures both the heating efficiency of the sewage and the protection of the living environment of the microorganisms. Attached Figure Description
[0022] Figure 1 This is a three-dimensional structural diagram of the present invention.
[0023] Figure 2 This is a schematic diagram of the three-dimensional structure of the filter body assembly of the present invention.
[0024] Figure 3 This is a schematic diagram of the first cross-sectional structure of the filter body assembly of the present invention.
[0025] Figure 4 This is a schematic diagram of the second cross-sectional structure of the filter body assembly of the present invention.
[0026] Figure 5 This is a schematic diagram of the three-dimensional structure of the biofilter layer assembly of the present invention.
[0027] Figure 6 This is a schematic diagram of the first cross-sectional structure of the biofilter layer assembly of the present invention.
[0028] Figure 7 for Figure 6 A magnified structural diagram at point A.
[0029] Figure 8 This is a schematic diagram of the second cross-sectional structure of the biofilter layer assembly of the present invention.
[0030] Figure 9 for Figure 8 A magnified structural diagram at point B.
[0031] Figure 10 This is a schematic diagram of the three-dimensional structure of the biological packing material of the present invention.
[0032] Figure 11 This is a schematic cross-sectional view of the biological packing material of the present invention.
[0033] Figure 12 This is a schematic diagram of the three-dimensional structure of the water storage tank assembly of the present invention.
[0034] In the diagram: 1. Filter body; 101. Main inlet channel; 102. Inlet overflow weir; 103. Inlet weir; 104. Inlet valve; 105. Drain valve; 106. Main drainage channel; 11. Inlet trough; 111. Water distribution hole; 112. Inlet hole; 12. Biological filter layer; 121. Mounting frame; 122. Sliding frame; 123. Biological packing material; 1231. Shell; 1232. Through hole; 12 33. Fiber cloth; 124. Partition plate; 125. Electromagnet; 126. Spring; 127. Iron block; 13. Backwash tank; 14. Quartz sand filter media layer; 15. Support layer; 16. Filter plate; 17. Long-handled filter head; 18. Water outlet tank; 2. Water storage tank; 3. Backwash assembly; 31. Backwash air pipe; 32. First valve; 33. Backwash water pipe; 34. Second valve; 35. Third valve. Detailed Implementation
[0035] The features and exemplary embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific configurations and algorithms presented below, but covers any modifications, substitutions, and improvements to elements, components, and algorithms without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description in order to avoid unnecessarily obscuring the invention.
[0036] Example 1, referring to Figures 1-12In the first embodiment of the present invention, a V-shaped filter for sewage treatment is provided. The V-shaped filter for sewage treatment includes multiple filter bodies 1. Each filter body 1 is provided with an inlet tank 11, a biological filter layer 12, a quartz sand filter media layer 14, a support layer 15, a filter plate 16 and an outlet tank 18 arranged from top to bottom. Multiple long-handled filter heads 17 are fixed on the filter plate 16. The biological filter layer 12 includes an installation frame 121 fixed in the filter body 1 and a multi-layer sliding frame 122 that is slidably disposed in the installation frame 121 in the horizontal direction. Each sliding frame 122 is divided into multiple channels by multiple partitions 124, and multiple biological packing materials 123 are fixed in each channel. An iron block 127 is fixedly installed on each sliding frame 122. An electromagnet 125 and a spring 126 are installed on the mounting frame 121 corresponding to each sliding frame 122. The spring 126 is a return spring, with one end fixed to the mounting frame 121 and the other end abutting against the side of the sliding frame 122. The spring 126 is sleeved on the outside of the electromagnet 125 or arranged parallel to the sliding direction of the sliding frame 122. When the electromagnet 125 is energized and attracts the iron block 127, causing the sliding frame 122 to be misaligned, the spring 126 is compressed. When the electromagnet 125 is de-energized, the elastic force of the spring 126 drives the sliding frame 122 to return to the aligned position.
[0037] The partition 124 is made of thermally conductive material and has a heating wire coil inside it; The filter body 1 is equipped with an inlet water temperature monitoring device; When the inlet water temperature monitoring device detects that the inlet water temperature is lower than the set threshold, it energizes the heating wire to heat it, and at the same time, the electromagnet 125 is energized, causing the multi-layer sliding frame 122 to be misaligned, so that the water flow channel changes from a vertical straight path to a tortuous path.
[0038] The inlet tank 11 has a V-shaped structure, and its side wall has a water distribution hole 111 located above the biological filter layer 12. The filter body 1 has an inlet hole 112 located at the end of the inlet tank 11.
[0039] Each filter body 1 is also equipped with an inlet main channel 101, an inlet overflow weir 102, an inlet weir 103 and an inlet valve 104. An inlet valve 104 is provided between the inlet main channel 101 and the inlet overflow weir 102. Sewage enters the inlet overflow weir 102 and the inlet weir 103 in sequence through the inlet valve 104 and then flows into the inlet trough 11 through the inlet hole 112.
[0040] The inlet water temperature monitoring device is a temperature sensor installed inside the inlet hole 112.
[0041] The quartz sand filter media layer 14 uses uniformly sized quartz sand to intercept impurities in the wastewater; the support layer 15 uses graded gravel to reduce the probability of impurities clogging the long-handled filter head 17; the long-handled filter head 17 is made of ABS engineering plastic and is arranged in a uniform matrix.
[0042] The main controller is electrically connected to the inlet water temperature monitoring device, the heating wire and the electromagnet 125. The main controller can be a conventional known device such as a computer for control, which will not be described in detail here.
[0043] During use, sewage enters through the main inlet channel 101, passes through the inlet valve 104 and then sequentially enters the inlet overflow weir 102 and the inlet weir 103. It then flows into the V-shaped inlet trough 11 through the inlet hole 112 and is evenly distributed above the biological filter layer 12 through the water distribution holes 111 on the side wall of the inlet trough 11. During normal operation, the sewage submerges the top of the inlet trough 11 to reduce the disturbance caused by the sewage falling. The sewage passes through the biological filter layer 12, the quartz sand filter media layer 14, the support layer 15 and the long-handled filter head 17 on the filter plate 16 from top to bottom, and flows out through the bottom outlet trough 18.
[0044] In winter or cold regions, the influent temperature of wastewater is low. When the temperature sensor located inside the inlet 112 detects that the influent temperature is below a set threshold, the main controller energizes the heating wire to heat the wastewater. Simultaneously, it energizes the electromagnet 125 to cause the multi-layer sliding frame 122 to shift out of alignment, and the partitions 124 within the multi-layer sliding frame 122 to shift out of alignment. Figure 8 As shown, the water flow channel changes from a vertical straight path to a tortuous path. On the one hand, the heating wire directly heats the sewage flowing through the baffle 124, rapidly raising the water temperature. This helps to raise the water temperature of the subsequent denitrifying bacteria, thereby improving the metabolic activity of the denitrifying bacteria. On the other hand, the tortuous flow channel formed by the staggered sliding frame 122 increases the contact time between the sewage and the heating baffle 124, ensuring that the sewage temperature is fully raised to a suitable range. At the same time, it prolongs the contact time between the sewage after the water temperature rises and the denitrifying bacteria on the biological packing 123, making up for the problem of reduced nitrogen removal efficiency caused by insufficient microbial activity under low temperature conditions. This ensures that the filter can still stably and efficiently remove nitrogen from the sewage when the influent is at low temperature.
[0045] The heating wire disc is placed inside the heat-conducting partition 124, increasing the direct contact area between the heating element and the sewage. This results in a shorter heat transfer path and less heat loss, leading to lower energy consumption and more uniform heating compared to external heating methods. Meanwhile, the biological packing material 123 includes a shell 1231 and a flexible fiber cloth 1233 fixedly connected inside the shell 1231. The shell 1231 has through holes 1232. The shell 1231 of the biological packing material 123 is made of heat-insulating material, which can effectively prevent the heat from the partition 124 from being directly conducted to the inside of the biological packing material 123. This achieves the purpose of heat insulation protection for the microorganisms attached to the flexible fiber cloth 1233 inside the biological packing material 123, ensuring both heating efficiency and protecting the living environment of the microorganisms.
[0046] Example 2, refer to Figures 3-11 This is the second embodiment of the present invention, which differs from the first embodiment in that: The biological packing material 123 includes a shell 1231 and a flexible fiber cloth 1233 fixedly connected inside the shell 1231. The shell 1231 has through holes 1232. The shell 1231 is a spherical or cylindrical hollow structure, specifically made of foamed polypropylene material. Foamed polypropylene has a closed-cell structure and is filled with air. Air is an excellent heat insulation medium, which can effectively prevent the heat from the partition 124 from being conducted into the biological packing material 123, avoiding thermal shock to the denitrifying bacteria inside the packing material during the heating process. The flexible fiber cloth 1233 is made of polyester fiber or nylon material, providing sufficient attachment surface area for denitrifying bacteria.
[0047] The microorganisms attached to the biological packing 123 are denitrifying bacteria, which convert nitrates into nitrogen gas in an anaerobic environment to reduce the nitrogen content in wastewater. The suitable survival temperature for denitrifying bacteria is 15℃-35℃, and the optimal metabolic activity temperature is 20℃-30℃. Their metabolic activity decreases significantly when the temperature is below 10℃. The set threshold is set according to the survival temperature of denitrifying bacteria, and the set threshold is 15℃. When the temperature sensor detects that the influent temperature is below 15℃, the main controller starts the low-temperature regulation mode; when the influent temperature rises back to above 25℃, the main controller controls the electromagnet 125 to de-energize, so that the sliding frame 122 returns to the vertical alignment state, restoring the straight flow channel.
[0048] The electromagnet 125 is intermittently switched on and off. When the electromagnet 125 is switched on, it attracts the iron block 127, causing the slide frame 122 to shift. When the power is switched off, the spring 126 drives the slide frame 122 to reset, thereby realizing the reciprocating swaying of the slide frame 122, which is used to reduce the adhesion of nitrogen gas produced by denitrifying bacteria.
[0049] During operation, when the inlet water temperature is below 15℃, the main controller activates the low-temperature regulation mode, the heating wire is energized, and the electromagnet 125 is energized to cause the sliding frame 122 to be misaligned, forming a tortuous flow channel. At the same time, the electromagnet 125 is intermittently energized to achieve the reciprocating shaking of the sliding frame 122. This shaking can effectively shake off nitrogen bubbles attached to the biological packing 123, reduce the accumulation of nitrogen on the surface of the biological packing 123, and avoid the reduction of effective biological contact area and blockage of water passage caused by nitrogen attachment. This reduces the nitrogen removal frequency. The nitrogen removal operation only requires the introduction of backwash water to carry away the shaken nitrogen bubbles, reducing the water volume, energy consumption and time required for conventional nitrogen removal, extending the working cycle of the V-type filter, and improving the overall operating efficiency of the V-type filter.
[0050] When the wastewater temperature exceeds a set threshold, it reaches the optimal temperature for denitrifying bacteria to form and metabolize. Specifically, when the influent temperature is above 25°C, the denitrifying bacteria are in their optimal metabolic activity range. At this time, the main controller de-energizes the electromagnet 125, and the multi-layer sliding frame 122 remains vertically aligned under the action of the spring 126. The water flow channel is a short, vertical path, allowing wastewater to quickly pass through the biological filter layer 12, fully utilizing the high metabolic activity of the denitrifying bacteria to achieve efficient nitrogen removal while ensuring the filter's treatment throughput. When the influent temperature is between 15°C and 25°C, a low-temperature adjustment mode can be maintained or switched to normal mode as needed.
[0051] Driven by electromagnet 125 and spring 126, slide frame 122 can achieve both misalignment holding under low temperature conditions and intermittent dynamic reciprocating swaying. One drive mechanism simultaneously realizes the dual functions of flow channel adjustment and nitrogen adsorption prevention. It has a compact structure, simple control, and no need to add an additional shaking device, thus reducing equipment cost and failure rate.
[0052] The flexibility of the flexible fiber cloth 1233 can absorb some of the mechanical energy generated when the sliding frame 122 shakes, preventing the biofilm from detaching over a large area due to shaking. At the same time, the slight deformation of the flexible fiber cloth 1233 can break the adhesion between nitrogen bubbles and the surface of the fiber cloth, promoting the separation and floating of nitrogen bubbles, thereby achieving the dual effect of protecting the integrity of the biofilm and effectively desorbing nitrogen.
[0053] The remaining structure is the same as that in Example 1.
[0054] Example 3, referring to Figures 1-4 and Figure 12 This is the third embodiment of the present invention, which differs from the second embodiment in that: A water storage tank 2 is provided on one side of the filter body 1. A backwashing component 3 is provided between the water storage tank 2 and the outlet tank 18. The backwashing component 3 is used to introduce backwashing water or backwashing air into the filter body 1.
[0055] The backwash assembly 3 includes a backwash air pipe 31, a backwash water pipe 33, and corresponding first valve 32, second valve 34, and third valve 35. The backwash air pipe 31 is used to introduce backwash air into the outlet tank 18, and the backwash water pipe 33 is used to introduce backwash water into the outlet tank 18. The first valve 32 is installed on the backwash air pipe 31, and the second valve 34 and the third valve 35 are installed on the backwash water pipe 33.
[0056] The filter body 1 is provided with a backwashing trough 13 with an inclined bottom surface. Inside the filter body 1, at the bottom end of the backwashing trough 13, there is a drainage main channel 106 for discharging backwashing wastewater. A drain valve 105 is provided between the backwashing trough 13 and the drainage main channel 106.
[0057] During use, in the process of sewage filtration, the second valve 34 is opened, and the water in the outlet tank 18 flows into the storage tank for storage or discharge through the second valve 34.
[0058] When the filter needs to undergo nitrogen removal, nitrogen bubbles are generated during the metabolism of denitrifying bacteria and adhere to the biological packing 123. With the reciprocating swaying of the sliding frame 122, the slight deformation of the flexible fiber cloth 1233 causes most of the nitrogen bubbles to detach from the biofilm surface. However, the remaining bubbles still need to be carried out of the filter layer to avoid air blockage and affecting the wastewater treatment efficiency. At this time, the third valve 35 on the backwash water pipe 33 is opened, and clean water is drawn from the water storage tank 2 through the external water pump and introduced into the filter body 1 from bottom to top through the outlet trough 18 for two minutes. The upward flow of backwash water carries the nitrogen bubbles that have been shaken off and suspended in the water upward. After passing through the biological filter layer 12, the nitrogen bubbles rise to the water surface and burst naturally. The nitrogen removal operation only requires the introduction of backwash water and does not require the introduction of backwash air, avoiding the impact of high-frequency backwashing on the biofilm. The reciprocating swaying of the sliding frame 122 reduces the nitrogen removal frequency and reduces the water volume and energy consumption required for conventional nitrogen removal, thereby improving the wastewater treatment efficiency.
[0059] When the filter needs backwashing, the backwashing is triggered by either timed triggering or differential pressure triggering. Timed triggering occurs every 24 to 48 hours, while differential pressure triggering automatically starts backwashing when the pressure difference across the filter bed reaches 0.10 MPa. The backwashing process employs a combined air-water backwashing technology, and the procedure is as follows: First, separate air washing is performed: close the second valve 34, open the drain valve 105 to lower the sewage level, open the first valve 32 on the backwash air pipe 31, and introduce air through an external blower for separate air washing for three minutes. At the same time, the inlet valve 104 is kept slightly open, and the sewage flows through the water distribution holes 111 on the inlet tank 11 to achieve surface cleaning, so that the floating intercepted matter and pollutants are flushed into the middle backwash tank 13. The airflow forms strong disturbance in the filter layer, and the filter media is in a slightly expanded state. The shearing force and rubbing action generated by the high-speed rise of the bubbles make the filter media particles fully rubbed, effectively peeling off the pollutants and intercepted matter attached to the surface of the filter media. The second is simultaneous air and water backwashing: while continuing to supply air, open the third valve 35 on the backwash water pipe 33 to introduce clean water for simultaneous air and water backwashing for five minutes. The water flows upward, quickly carrying the dirt that has been scrubbed off out of the filter layer, and at the same time, it achieves surface cleaning through the water distribution hole 111 on the water inlet tank 11, so that the floating intercepted matter and pollutants are flushed into the middle backwash tank 13 and enter the main drainage channel 106 through the drain valve 105. The third stage is separate water flushing: close the first valve 32 to stop the air supply, and continue to introduce backwash water for separate water flushing for three minutes. The purpose is to thoroughly remove the suspended solids remaining in the filter layer and the gas in the filter tank, while creating an anaerobic environment for denitrifying bacteria and allowing the filter media to settle and return to its position quickly to prevent sand from escaping.
[0060] During the backwashing process described above, the electromagnet 125 is de-energized, and the sliding frame 122 returns to its vertical alignment under the action of the spring 126. The through channel is open from top to bottom, resulting in low flow resistance and uniform distribution of the backwash fluid, effectively removing trapped suspended solids and aged, detached biofilm. The trapped solids and detached biofilm float to the surface with the backwash wastewater and are discharged through the backwashing trough 13, which is inclined at the bottom, and the main drainage channel 106. The drainage valve 105 controls the drainage process. After backwashing is completed, the first valve 32 and the third valve 35 are closed, and the second valve 34 is opened, restoring the filter to normal filtration operation.
[0061] The remaining structure is the same as that in Example 2.
[0062] Different technical features appearing in different embodiments can be combined to achieve beneficial effects. Those skilled in the art, based on a study of the drawings, specification, and claims, should be able to understand and implement other variations of the disclosed embodiments. In the claims, the term "comprising" does not exclude other means or steps; the indefinite article "a" does not exclude a plurality; the terms "first" and "second" are used to identify names rather than to indicate any particular order. No reference numerals in the claims should be construed as limiting the scope of protection. The functionality of multiple parts appearing in the claims can be implemented by a single hardware or software module. The appearance of certain technical features in different dependent claims does not mean that these technical features cannot be combined to achieve beneficial effects.
Claims
1. A V-type filter for wastewater treatment, characterized in that: It includes multiple filter bodies (1), and each filter body (1) is provided with an inlet tank (11), a biological filter layer (12), a quartz sand filter media layer (14), a support layer (15), a filter plate (16) and an outlet tank (18) from top to bottom. Multiple long-handled filter heads (17) are fixed on the filter plate (16). The biological filter layer (12) includes an installation frame (121) fixed in the filter body (1) and a multi-layer sliding frame (122) slidably disposed in the installation frame (121) in the horizontal direction. Each layer of the sliding frame (122) is divided into multiple channels by multiple partitions (124), and multiple biological packing materials (123) are fixed in each channel. An iron block (127) is fixedly installed on each layer of the sliding frame (122), and an electromagnet (125) and a spring (126) are provided on the mounting frame (121) corresponding to each layer of the sliding frame (122). The partition (124) is made of thermally conductive material and has a heating wire coil inside; The filter body (1) is equipped with an inlet water temperature monitoring device; When the inlet water temperature monitoring device detects that the inlet water temperature is lower than the set threshold, it energizes the heating wire and heats it. At the same time, the electromagnet (125) is energized, causing the multi-layered sliding frames (122) to be misaligned, so that the water flow channel changes from a vertical straight path to a tortuous path.
2. The V-type filter for wastewater treatment according to claim 1, characterized in that: The inlet tank (11) has a V-shaped structure, and a water distribution hole (111) is provided on its side wall above the biological filter layer (12). The filter body (1) has an inlet hole (112) at the end of the inlet tank (11).
3. A V-type filter for wastewater treatment according to claim 2, characterized in that: Each filter body (1) is also provided with an inlet main channel (101), an inlet overflow weir (102), an inlet weir (103) and an inlet valve (104). An inlet valve (104) is provided between the inlet main channel (101) and the inlet overflow weir (102). Sewage enters the inlet overflow weir (102) and the inlet weir (103) in sequence through the inlet valve (104) and then flows into the inlet tank (11) through the inlet hole (112).
4. A V-type filter for wastewater treatment according to claim 2, characterized in that: The inlet water temperature monitoring device is a temperature sensor installed inside the inlet hole (112).
5. A V-type filter for wastewater treatment according to claim 1, characterized in that: The biological filler (123) includes a shell (1231) and a flexible fiber cloth (1233) fixedly connected inside the shell (1231), and the shell (1231) has through holes (1232).
6. A V-type filter for wastewater treatment according to claim 1, characterized in that: The microorganisms attached to the biological packing material (123) are denitrifying bacteria, which are used to convert nitrates into nitrogen gas in an anaerobic environment to reduce the nitrogen content in wastewater.
7. A V-type filter for wastewater treatment according to claim 6, characterized in that: The electromagnet (125) is intermittently switched on and off. When the electromagnet (125) is switched on, it attracts the iron block (127) and causes the sliding frame (122) to shift. When the power is switched off, the spring (126) drives the sliding frame (122) to reset, thereby realizing the reciprocating swaying of the sliding frame (122) to reduce the adhesion of nitrogen gas produced by denitrifying bacteria.
8. A V-type filter for wastewater treatment according to claim 1, characterized in that: A water storage tank (2) is provided on one side of the filter body (1), and a backwashing component (3) is provided between the water storage tank (2) and the outlet tank (18). The backwashing component (3) is used to introduce backwashing water or backwashing air into the filter body (1).
9. A V-type filter for wastewater treatment according to claim 8, characterized in that: The backwash assembly (3) includes a backwash air pipe (31), a backwash water pipe (33), and corresponding first valve (32), second valve (34), and third valve (35). The backwash air pipe (31) is used to introduce backwash air into the outlet tank (18), and the backwash water pipe (33) is used to introduce backwash water into the outlet tank (18). The first valve (32) is installed on the backwash air pipe (31), and the second valve (34) and third valve (35) are installed on the backwash water pipe (33).
10. A V-type filter for wastewater treatment according to claim 8, characterized in that: The filter body (1) is provided with a backwashing tank (13) with an inclined bottom surface. The filter body (1) is provided with a drainage main channel (106) for discharging backwashing wastewater at the bottom end of the backwashing tank (13). A drainage valve (105) is provided between the backwashing tank (13) and the drainage main channel (106).