Multistage upflow and downflow reoxygenation bucket-shaped biological filter

Abstract

The invention belongs to the technical field of water treatment, and particularly discloses a multi-stage up-down flow reoxygenation bucket-shaped biological filter. An up-flow funnel and a down-flow funnel of the funnel-shaped biological filter are both big-end-up funnels, a plurality of flow guide holes are evenly distributed in the position, close to the edge, of an upper opening of the up-flow funnel in the circumferential direction, flow guide silk threads are hung on the flow guide holes of the up-flow funnel, and a sealing plug is arranged at a lower opening of the up-flow funnel. The up-flow funnels and the down-flow funnels are connected in series at intervals up and down to form funnel groups; and a plurality of funnel groups are arranged above the funnel bracket in series at intervals. The up-flow funnels and the down-flow funnels are connected in series to form the funnel groups, and then a plurality of funnel groups are arranged above the funnel bracket at intervals in series, so that the contact area and time of surface water and air are effectively improved, multiple exchanges between the surface water and deep water are realized by utilizing a limited height difference, a multi-stage A / O reaction is formed, and a multiple-reoxygenation effect is achieved; the device has the characteristics of simple structure, high reoxygenation mass transfer rate, good denitrification effect, energy conservation and consumption reduction.

Description

Technical Field

[0001] The invention belongs to the technical field of water treatment, and in particular relates to a multi-stage up-and-down-flow reoxygenation bucket-shaped biofilter with simple structure, high reoxygenation mass transfer rate, good denitrification effect, energy saving and consumption reduction. Background Art

[0002] Aeration equipment is the most energy-intensive facility in a sewage treatment plant, accounting for over 50% of its energy consumption. Therefore, aeration and reoxygenation are key targets for energy conservation and consumption reduction in sewage treatment plants. Currently, common aeration methods in sewage treatment plants are divided into forced aeration and surface aeration. Forced aeration involves pumping air below the water surface to increase dissolved oxygen, while surface aeration disperses water into the air to increase dissolved oxygen. However, both methods involve the transfer of gas and liquid phases, resulting in higher energy consumption.

[0003] Because hypoxia often occurs in deep water layers, while surface water has a higher dissolved oxygen content, even reaching saturation, surface water with a higher dissolved oxygen content can be injected into the deeper layers, or water with a lower dissolved oxygen content from the deep layers can be transported to the surface for oxygen absorption. The key to both approaches is to enhance vertical mixing of the water through physical means, leveraging the high oxygen content of the surface water or the atmospheric reoxygenation capacity to increase the overall DO concentration in the water. The exchange and reoxygenation of surface and deep waters only involves exchange within the liquid phase. According to the Bernoulli equation, theoretically, its energy consumption can be infinitely low, making it an extremely energy-efficient aeration method. Therefore, it is expected to become the third most important aeration method after forced aeration and surface aeration.

[0004] In the prior art, the exchange and reoxygenation of surface water and deep water can be divided into different schemes according to the implementation method, such as mechanical power drive type, non-powered structure type and solar power drive type.

[0005] The mechanically powered type utilizes a water pump as the primary power source to achieve directional water transport, and uses aeration plates to exchange and reoxygenate surface water with deep water. While the reoxygenation efficiency is high, water quality improvement is immediate, and it can be applied to water depths greater than 5m, making it more flexible in application, it also has drawbacks such as the need for a stable power supply for continuous operation, resulting in high energy consumption, and a high maintenance workload due to the need for regular maintenance to prevent clogging of underwater components (pumps and pipelines).

[0006] The non-powered structure is designed for water bodies that do not require rapid reoxygenation or have limited power supply (such as mountain ponds and natural rivers). For example, a ditch baffle system consisting of a lower baffle, a surface water baffle, and an upper baffle is installed within the ditch. This system causes the water to undergo a cycle of "upwelling → surface aeration → sinking" as it flows through, improving reoxygenation efficiency through multiple exchanges. Because it relies entirely on hydraulic potential energy, it has no operating costs. Moreover, the lack of mechanical disturbance avoids interference with aquatic life (especially fish spawning areas) and facilitates daily maintenance. However, because its reoxygenation rate depends on water velocity, baffle spacing, and the number of units, the single-stage DO increase capacity is relatively low, making it unsuitable for polluted water bodies that urgently need oxygenation. Furthermore, the ditch system requires sufficient length (usually >50m) and a drop (>30cm), which limits its use in flat or narrow areas.

[0007] The solar-driven type is a mechanical power-driven type that integrates solar photovoltaic panels. Although it solves the energy consumption problem and can often achieve "oxygenation + algae control + sediment remediation" simultaneously, it also has the problem of high initial investment costs for solar panels, batteries and monitoring systems, and difficult maintenance. In addition, it is necessary to switch to a backup power source (such as wind power) or reduce the frequency of operation on rainy days, which affects the continuity of reoxygenation. Summary of the Invention

[0008] In order to solve the problems mentioned in the above background technology, the present invention provides a multi-stage upstream and downstream reoxygenation bucket-shaped biofilter with simple structure, high reoxygenation mass transfer rate, good denitrification effect, energy saving and consumption reduction.

[0009] The multi-stage up-and-down flow reoxygenation bucket-shaped biological filter of the present invention is realized as follows: it includes a funnel bracket, an up-flow funnel, and a down-flow funnel. The up-flow funnel and the down-flow funnel are both funnels with a larger top and a smaller bottom. The up-flow funnel has a plurality of diversion holes evenly distributed circumferentially near the edge of the upper opening of the funnel. The up-flow funnel has a diversion thread extending downwardly suspended from the diversion holes. The lower opening of the up-flow funnel is provided with a sealing plug. The up-flow funnel and the down-flow funnel are arranged in series at intervals above and below to form a funnel group. A plurality of funnel groups are arranged in series at intervals above the funnel bracket.

[0010] Furthermore, the upstream funnel of the funnel group is arranged at the top and the downstream funnel is arranged at the bottom, and the minimum circumscribed circle diameter of the funnel upper opening of the downstream funnel is larger than the maximum circumscribed circle diameter of the several guide wires of the upstream funnel.

[0011] Furthermore, fillers are filled between the upstream funnel and the downstream funnel of the funnel group, and fillers are also filled in the upstream funnel of the topmost funnel group above the funnel support.

[0012] Furthermore, the length of the guide wire hanging on the guide hole is not greater than the vertical distance between the adjacent upstream funnel and downstream funnel, and the guide wire is made of a flexible hydrophilic material.

[0013] Furthermore, the vertical spacing between the upstream funnel and the downstream funnel in the funnel group is not less than the vertical spacing between adjacent funnel groups.

[0014] Furthermore, an emptying pipe with one end extending to the outside of the upper opening of the funnel is provided in the upstream funnel, and the opening of one end of the emptying pipe outside the upper opening of the funnel is located outside the upper opening of the downstream funnel of each funnel group.

[0015] Furthermore, one end of the emptying pipe outside the upper opening of the funnel is connected to an extension pipe to form a siphon pipe, or is connected to an extension pipe connected to a mechanical mud discharge device.

[0016] Furthermore, the angles formed by the connecting surface of the lowest opening end of each guide hole of the upstream funnel on the inner side of the funnel and the upper surface of the funnel upper opening of the downstream funnel and the horizontal plane are no more than 5%.

[0017] Furthermore, the downstream funnels of the bottom-most funnel group are directly fixed on the funnel bracket, and the relative positions of adjacent funnel groups and / or the upstream funnels and downstream funnels of the funnel groups are fixed by an annular bracket.

[0018] Furthermore, the upper opening of the upstream funnel of the topmost funnel group above the funnel bracket is provided with a water inlet pipe, and the lower opening of the downstream funnel of the bottommost funnel group of the funnel bracket is connected with a drain pipe.

[0019] The present invention has the following beneficial effects: 1. The present invention is mainly composed of core components such as a funnel bracket, an upstream funnel, and a downstream funnel. The structure of each component is simple and the connection method is clear, and there is no need for complex mechanical devices or precision control systems. Moreover, the upstream funnel and the downstream funnel are connected in series through upper and lower intervals to form a funnel group, and then a number of funnel groups are arranged in series above the funnel bracket. Not only is the overall assembly process simple, but the number of funnel groups can be flexibly adjusted according to actual needs to adapt to water treatment scenarios of different scales. At the same time, since there are no vulnerable mechanical power components, daily maintenance only requires regular inspection of the funnel connection stability, cleaning of excess biofilm attached to the filler surface, etc., which greatly reduces the maintenance difficulty and cost, and solves the problem of large maintenance workload of mechanical power-driven equipment.

[0020] 2. The present invention benefits from a unique multi-stage up-and-down flow design. The water forms a circulating flow pattern of "upstream → diversion → downstream → upstream again" in the filter tank, thereby utilizing a limited height difference to achieve multiple exchanges between surface water and deep water, forming a multi-stage A / O reaction and achieving multiple reoxygenation effects. The liquid surface at the top of the funnel can be in contact with the air for reoxygenation on the plane, and the diversion holes and diversion wires of the upstream funnel can also allow the water to be in contact with the air for reoxygenation in the vertical direction, thus completing the upgrade from two-dimensional plane reoxygenation to three-dimensional reoxygenation. This not only increases the contact area between the water and the air, but also prolongs the contact time. In addition, the mass transfer efficiency formed by the diversion wire far exceeds the vertical liquid film of the traditional aeration plate, thereby enhancing the gas-liquid mass transfer efficiency, overcoming the defect of low DO lifting capacity of the unpowered structure type single-stage, and can quickly increase the dissolved oxygen concentration in the water.

[0021] 3. The space between the upstream funnel and the downstream funnel of the present invention is filled with fillers, and the top upstream funnel is also filled with fillers. These fillers provide sufficient attachment carriers for microorganisms and can form dense biofilms. When the water flows through the filler layer, due to the difference in dissolved oxygen distribution during the upstream and downstream flow, different microenvironments such as aerobic zones and anoxic zones will be formed: in the aerobic zone, nitrifying bacteria convert ammonia nitrogen into nitrate nitrogen; in the anoxic zone, denitrifying bacteria reduce nitrate nitrogen to nitrogen gas, thereby achieving efficient denitrification. At the same time, the biofilm on the surface of the guide wire and the filler can also adsorb and degrade organic matter in the water, further improving the water purification effect, and solving the problem that traditional aeration technology only focuses on oxygenation and has limited denitrification effect.

[0022] 4. The present invention completely relies on the gravitational potential energy of the water body itself to achieve upstream and downstream circulation. It does not require mechanical power drive (such as water pumps, aerators, etc.) nor does it require auxiliary energy equipment such as solar photovoltaic panels, which fundamentally reduces energy consumption. Compared with solar-driven technology, it avoids the high initial equipment investment and energy instability caused by weather influences, and is particularly suitable for long-term large-scale applications.

[0023] 5. Unlike unpowered canal-type baffle systems, this bucket-shaped biofilter does not rely on specific terrain differences or long canal lengths. Instead, it achieves efficient reoxygenation through the vertical connection of funnel groups, making it suitable for installation and use in both flat areas and confined spaces. Furthermore, the reoxygenation rate can be flexibly adjusted by adjusting the number of funnel groups, filler type, and guide wire density. This system can meet both routine purification needs of generally contaminated water bodies and those requiring urgent oxygenation, offering a wide range of applications far beyond those of traditional unpowered technologies.

[0024] In summary, the present invention combines physical structure innovation (guide wire + multi-stage funnel group) with biological enhancement (filler) to achieve efficient reoxygenation and denitrification under the premise of zero energy consumption. This disruptive design simultaneously overcomes the four major industry pain points of low reoxygenation mass transfer rate, high energy consumption, difficult denitrification, and narrow adaptability, becoming the third high-efficiency and energy-saving aeration method after blast / surface aeration. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic structural diagram of the bucket-shaped biofilter of the present invention; Figure 2 This is an enlarged view of the upstream funnel structure of the present invention; Figure 3 It is an enlarged cross-sectional view of the downflow funnel of the present invention; Figure 4 This is an enlarged view of the annular support structure of the present invention; In the figure: 1-funnel bracket, 2-upflow funnel, 3-downflow funnel, 4-upper opening of funnel, 5-lower opening of funnel, 6-diversion hole, 7-diversion wire, 8-sealing plug, 9-filler, 10-drain pipe, 11-annular bracket. DETAILED DESCRIPTION

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments, but the present invention is not limited in any way. Any changes or improvements made based on the teachings of the present invention fall within the scope of protection of the present invention.

[0027] like Figure 1 、 2 As shown in Figure 3, the multi-stage up-and-down flow reoxygenation bucket-shaped biological filter of the present invention includes a funnel bracket 1, an up-flow funnel 2, and a down-flow funnel 3. The up-flow funnel 2 and the down-flow funnel 3 are both funnels with a larger top and a smaller bottom. The up-flow funnel 2 has a plurality of guide holes 6 uniformly distributed circumferentially near the edge of the funnel upper opening 4. The up-flow funnel 2 has a guide wire 7 extending downwardly suspended on the guide hole 6. The funnel lower opening 5 of the up-flow funnel 2 is provided with a sealing plug 8. The up-flow funnel 2 and the down-flow funnel 3 are arranged in series at intervals above and below to form a funnel group, and a plurality of funnel groups are arranged in series at intervals above the funnel bracket 1.

[0028] The upstream funnel 2 of the funnel group is arranged at the top and the downstream funnel 3 is arranged at the bottom. The minimum circumscribed circle diameter of the funnel upper opening 4 of the downstream funnel 3 is larger than the maximum circumscribed circle diameter of the guide wires 7 of the upstream funnel 2.

[0029] A filler 9 is filled between the upstream funnel 2 and the downstream funnel 3 of the funnel group, and a filler 9 is also filled in the upstream funnel 2 of the topmost funnel group above the funnel support 1 .

[0030] The filler 9 includes quartz sand, ceramsite or other existing flexible fillers or rigid fillers available in sewage treatment.

[0031] The length of the guide wire 7 hanging on the guide hole 6 is not greater than the vertical distance between the adjacent upstream funnel 2 and downstream funnel 3, and the guide wire 7 is made of flexible hydrophilic material.

[0032] The vertical spacing between the upstream funnel 2 and the downstream funnel 3 in the funnel group is not less than the vertical spacing between adjacent funnel groups.

[0033] An emptying pipe 10 with one end extending to the outside of the funnel upper opening 4 is provided in the upstream funnel 2. The opening of one end of the emptying pipe 10 outside the funnel upper opening 4 is located outside the funnel upper opening 4 of the downstream funnel 3 of each funnel group.

[0034] The drain pipe 10 is an empty pipe arranged along the inner wall of the upstream funnel 2 and one end of the drain pipe extends to the lower funnel opening 5 of the upstream funnel 2 .

[0035] One end of the emptying pipe 10 outside the upper opening 4 of the funnel is connected to an extension pipe to form a siphon pipe, or is connected to an extension pipe connected to a mechanical mud discharge device.

[0036] The angle formed between the connecting surface of the lowest opening of each guide hole 6 of the upstream funnel 2 on the inner side of the funnel and the upper surface of the funnel top opening 4 of the downstream funnel 3 and the horizontal plane is no more than 5%. The purpose is to ensure that the guide holes 6 of the upstream funnel 2 are basically on the same horizontal plane and the upper surface of the funnel top opening 4 of the downstream funnel 3 is as straight as possible. Otherwise, the outflow water may be concentrated on one side, thereby reducing the contact time with air and resulting in poor reoxygenation effect.

[0037] like Figure 4 As shown, the downstream funnel 3 of the bottom funnel group of the present invention is directly fixed on the funnel bracket 1, and the relative positions between adjacent funnel groups and / or between the upstream funnel 2 and the downstream funnel 3 of the funnel group are fixed by the annular bracket 11.

[0038] The upper funnel opening 4 of the upstream funnel 2 of the topmost funnel group above the funnel bracket 1 is provided with a water inlet pipe, and the lower funnel opening 5 of the downstream funnel 3 of the bottommost funnel group of the funnel bracket 1 is connected with a drain pipe.

[0039] The working principle and working process of the present invention: like Figure 1 、 2As shown in Figures 3 and 4, when working, sewage is introduced into the top upstream funnel 2 from the water inlet pipe. Under the action of its own gravity, the water flows out from the diversion hole 6 of the top upstream funnel 2 and drips along the diversion wire 7 to realize the exchange of water and air. In this way, it passes through the upstream funnel 2 and the downstream funnel 3 of each funnel group from top to bottom, forming a circular flow pattern of "upstream → diversion → downstream → upstream again", realizing multiple exchanges between surface water and deep water, and finally forming a multi-stage A / O reaction and achieving multiple reoxygenation effects, and flows out from the funnel bottom port 5 of the downstream funnel 3 of the bottom funnel group to the drain pipe to complete sewage filtration.

[0040] During the filtration of sewage in the bucket-shaped biofilter of the present invention, the filler 9 between the upstream funnel 2 and the downstream funnel 3 provides ample attachment carriers for microorganisms, allowing for the formation of a dense biofilm. As water flows through the filler 9 layer, differences in dissolved oxygen distribution between upstream and downstream flow create distinct microenvironments, such as aerobic and anoxic zones. In the aerobic zone, nitrifying bacteria convert ammonia nitrogen into nitrate nitrogen; in the anoxic zone, denitrifying bacteria reduce nitrate nitrogen to nitrogen gas, thereby achieving efficient denitrification. Simultaneously, the biofilm on the surfaces of the guide wires 7 and the filler 9 can also adsorb and degrade organic matter in the water, further enhancing water purification effectiveness and resolving the problem of traditional aeration technology focusing solely on oxygenation and having limited denitrification effects. Furthermore, the guide wires 7 not only increase the contact area between the water and air, but also extend the contact time. Furthermore, the mass transfer efficiency of the guide wires 7 far exceeds that of the vertical liquid film of a traditional aeration plate, thereby enhancing gas-liquid mass transfer efficiency.

[0041] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A multi-stage upstream and downstream reoxygenation bucket-shaped biofilter, characterized by: The invention comprises a funnel bracket (1), an upstream funnel (2), and a downstream funnel (3), wherein the upstream funnel (2) and the downstream funnel (3) are both funnels with a larger upper portion and a smaller lower portion, the upstream funnel (2) is provided with a plurality of guide holes (6) uniformly distributed circumferentially near the edge of the upper opening (4) of the funnel, the upstream funnel (2) is provided with a guide wire (7) extending downwardly suspended from the guide hole (6), the lower opening (5) of the upstream funnel (2) is provided with a sealing plug (8), the upstream funnel (2) and the downstream funnel (3) are arranged in series at intervals above and below to form a funnel group, and a plurality of funnel groups are arranged in series at intervals above the funnel bracket (1).

2. The multi-stage upstream and downstream reoxygenation bucket-shaped biofilter according to claim 1, characterized in that: The upflow funnel (2) of the funnel group is arranged at the top and the downflow funnel (3) is arranged at the bottom, and the minimum circumscribed circle diameter of the funnel upper opening (4) of the downflow funnel (3) is larger than the maximum circumscribed circle diameter of the plurality of guide wires (7) of the upflow funnel (2).

3. The multi-stage upstream and downstream reoxygenation bucket-shaped biofilter according to claim 2, characterized in that: A filler (9) is filled between the upstream funnel (2) and the downstream funnel (3) of the funnel group, and a filler (9) is also filled in the upstream funnel (2) of the topmost funnel group above the funnel support (1).

4. The multi-stage upstream and downstream reoxygenation bucket-shaped biofilter according to claim 2, characterized in that: The length of the guide wire (7) suspended on the guide hole (6) is no greater than the vertical distance between the adjacent upstream funnel (2) and downstream funnel (3), and the guide wire (7) is made of a flexible hydrophilic material.

5. The multi-stage upstream and downstream reoxygenation bucket-shaped biofilter according to any one of claims 1 to 4, characterized in that: The vertical spacing between the upstream funnel (2) and the downstream funnel (3) in the funnel group is not less than the vertical spacing between adjacent funnel groups.

6. The multi-stage upstream and downstream reoxygenation bucket-shaped biofilter according to claim 5, characterized in that: An exhaust pipe (10) having one end extending outside the upper opening (4) of the funnel is provided in the upstream funnel (2). The exhaust pipe (10) has one end opening outside the upper opening (4) of the funnel and is located outside the upper opening (4) of the downstream funnel (3) of each funnel group.

7. The multi-stage upstream and downstream reoxygenation bucket-shaped biofilter according to claim 6, characterized in that: One end of the drain pipe (10) outside the upper opening (4) of the funnel is connected to an extension pipe to form a siphon pipe, or is connected to an extension pipe connected to a mechanical mud discharge device.

8. The multi-stage upstream and downstream reoxygenation bucket-shaped biofilter according to claim 5, characterized in that: The angles formed by the connecting surface of the lowest opening of each guide hole (6) of the upstream funnel (2) on the inner side of the funnel and the upper surface of the funnel upper opening (4) of the downstream funnel (3) and the horizontal plane are no greater than 5%.

9. The multi-stage upstream and downstream reoxygenation bucket-shaped biofilter according to claim 5, characterized in that: The downflow funnel (3) of the bottom funnel group is directly fixed on the funnel bracket (1), and the relative positions between adjacent funnel groups and / or between the upflow funnel (2) and the downflow funnel (3) of the funnel group are fixed by the annular bracket (11).

10. The multi-stage upstream and downstream reoxygenation bucket-shaped biofilter according to claim 5, characterized in that: The upper funnel opening (4) of the upstream funnel (2) of the topmost funnel group above the funnel bracket (1) is provided with a water inlet pipe, and the lower funnel opening (5) of the downstream funnel (3) of the bottommost funnel group of the funnel bracket (1) is connected to a drainage pipe.

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