Multistage upflow-downflow reoxygenation sewage treatment tank
By designing a multi-stage upstream and downstream reoxygenation wastewater treatment tank, the system utilizes the gravity difference of the wastewater itself to achieve three-dimensional exchange, solving the problems of high aeration energy consumption and poor deep water reoxygenation effect, thus achieving efficient and energy-saving wastewater treatment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- KUNMING ENG & RES INST OF NONFERROUS METALLURGY
- Filing Date
- 2025-09-02
- Publication Date
- 2026-07-31
AI Technical Summary
Existing wastewater treatment plants use high-energy-consuming aeration methods and have poor deep water reoxygenation effects. Current technologies struggle to achieve efficient water exchange and reoxygenation while conserving energy.
The wastewater treatment system employs multi-stage upflow and downflow reoxygenation tanks, which are stacked in a tower-like structure to form a multi-layer reoxygenation combination tank. It utilizes the gravity difference of the wastewater itself to form a three-dimensional exchange process. Combined with diversion pipes and overflow facilities, it achieves vertical exchange between the surface high-oxygen water and the deep low-oxygen water. The packing layer increases the contact area and simplifies the equipment structure.
It significantly reduces energy consumption, improves reoxygenation mass transfer efficiency, shortens the mixing cycle, is suitable for industrial wastewater treatment, has a simple structure, and is easy to expand and maintain.
Smart Images
Figure CN224578136U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of water treatment technology, specifically relating to a multi-stage upstream and downstream reoxygenation sewage treatment tank with simple structure, high reoxygenation mass transfer rate, energy saving and consumption reduction, and small footprint. Background Technology
[0002] Aeration is a core component of wastewater treatment. Its purpose is to oxygenate the wastewater and agitate the mixed liquor, providing conditions for aerobic microorganisms to survive and degrade pollutants. Aeration equipment is the most energy-intensive facility in a wastewater treatment plant, accounting for more than 50% of the plant's total energy consumption. Therefore, aeration and reoxygenation are key areas for energy conservation and cost reduction in wastewater treatment plants.
[0003] Currently, the common aeration methods in wastewater treatment plants are mainly divided into blower aeration and surface aeration. Blower aeration delivers air to the water surface to increase dissolved oxygen, while surface aeration disperses water into the air to increase dissolved oxygen. However, both blower aeration and surface aeration involve the transport of gas and liquid phases, resulting in high energy consumption.
[0004] Oxygen deficiency in aquatic bodies is often due to the low temperature and high density of deep water, which is isolated from the air, causing a continuous decrease in dissolved oxygen and even leading to an anaerobic state. Surface water, on the other hand, has a high temperature, low density, and is in contact with the air, resulting in abundant dissolved oxygen. Therefore, through artificial intervention or natural means, surface water can be injected into deeper layers, or deep water can be transported to the surface to absorb oxygen. The high oxygen content of surface water or the reoxygenation capacity of the atmosphere can be used to increase the dissolved oxygen (DO) concentration in the water, thus comprehensively improving the aquatic ecological environment. Furthermore, the reoxygenation exchange between surface and deep water involves only internal liquid-phase exchange. According to Bernoulli's equation, its energy consumption can theoretically be infinitesimally small, making it an extremely energy-efficient aeration method.
[0005] In existing technologies, there are numerous solutions for the exchange and reoxygenation of surface water and deep water. One approach utilizes high-speed rotation of impellers, brushes, or underwater propellers installed on the water surface to generate strong horizontal or vertical water flows, agitating the surface water and penetrating deeper layers, breaking the thermocline and promoting the mixing of high-oxygen surface water with low-oxygen deep water. While this method is simple in structure, highly efficient in mixing, relatively flexible in equipment installation, and technologically mature, it is energy-intensive due to its surface aeration nature. Another approach uses blowers to deliver air through pipes to the bottom of the water and release it, creating a "lifting" effect through rising bubbles, which drives the bottom water flow vertically upwards to achieve exchange and reoxygenation. This bubble lifting technology offers very high reoxygenation efficiency, does not violently agitate the bottom sediment, and is applicable to different water depths. However, it also suffers from high operating energy consumption, and the structure, construction, and maintenance are relatively complex due to the need to lay underwater aeration pipelines. To address this, some technologies utilize the water level differences of multi-level reservoirs (or ponds) to create a "cascade-wave" effect by periodically opening and closing gates to release or divert water. This propels surface water downstream, while low-oxygen water from downstream reservoirs replenishes upstream, forming a cascade reservoir / pond joint scheduling technology that facilitates vertical and horizontal exchange across levels. While this approach is low-cost and offers comprehensive benefits such as flood control and irrigation, it is difficult to apply to the reoxygenation of industrial wastewater, and the mixing cycle is relatively long (requiring several days to weeks). Additionally, there are bio-physical synergistic enhancement technologies that combine root disturbance of aquatic plants (such as submerged and floating-leaved plants) with artificial aeration, or utilize the adsorption-degradation effect of microbial carriers to reduce the oxygen consumption rate of deep water, indirectly enhancing reoxygenation efficiency. While these technologies have lower energy consumption and can improve the microenvironment of bottom sediments, they have lower wastewater treatment efficiency and poor adaptability to highly polluted water bodies, making them difficult to apply to the reoxygenation of industrial wastewater. Utility Model Content
[0006] In order to solve the problems mentioned in the background art, the present invention provides a multi-stage upflow and downflow reoxygenation sewage treatment tank with simple structure, high reoxygenation mass transfer rate, energy saving and consumption reduction, and small footprint.
[0007] The multi-stage upflow and downflow reoxygenation wastewater treatment tank of this utility model is implemented as follows: it includes a tower-shaped support, a reoxygenation combination tank, a guide pipe, an inlet pipe, and an outlet pipe. The tower-shaped support is stacked and fixed with multiple layers of reoxygenation combination tanks from top to bottom. Each reoxygenation combination tank includes a wastewater tank and a guide plate. The wastewater tank is vertically arranged in the guide plate. The outlet of the inlet pipe extends to the wastewater tank of the top reoxygenation combination tank of the tower-shaped support. The inlet of the outlet pipe is connected to the bottom end of the guide plate of the bottom reoxygenation combination tank of the tower-shaped support. The inlet of the guide pipe is connected to the bottom end of the upper guide plate of the adjacent reoxygenation combination tank. The outlet of the guide pipe extends to the lower wastewater tank of the adjacent reoxygenation combination tank.
[0008] Furthermore, the outlets of the inlet pipe and the guide pipe extend to the bottom central area of the corresponding sewage tank, and the sewage in the reoxygenation combination tank overflows from the overflow facility at the top of the sewage tank into the guide plate.
[0009] Furthermore, both the wastewater tank and the guide plate in the reoxygenation combined tank are horizontally arranged. The planar dimensions of the guide plate in the reoxygenation combined tank are larger than the planar dimensions of the wastewater tank, and the height of the guide plate in the reoxygenation combined tank is smaller than the height of the wastewater tank.
[0010] Furthermore, the overflow facility is a thin-walled overflow weir, a triangular overflow weir, or an overflow hole, and the bottom of the sewage tank is also provided with a sewage pipe and a sewage valve that penetrate the corresponding guide plate.
[0011] Furthermore, the wastewater tank is filled with a packing layer composed of ceramsite, activated carbon, and / or volcanic rock, and the outlets of the inlet pipe and the guide pipe extend to the bottom or the central area below the packing layer.
[0012] Furthermore, a number of guide wires are fixedly installed circumferentially on the outer edge of the overflow facility of the sewage tank, or a guide cloth is fixedly laid there, and the sewage in the sewage tank flows down along the guide wires or the guide cloth to the corresponding guide plate.
[0013] Furthermore, the non-connected parts of the guide wires or guide cloth on the sewage tank are not attached to the outer wall of the sewage tank, and both the guide wires and guide cloth are made of flexible hydrophilic materials.
[0014] Furthermore, the overflow facility edge of the sewage tank protrudes outward, and the guide wire or guide cloth is fixedly connected to the outwardly protruding overflow facility edge of the sewage tank and extends downward.
[0015] Furthermore, the portion of the guide cloth outside the sewage tank is inclined or arc-shaped to extend downwards.
[0016] Furthermore, at least two independent guide pipes are installed between the bottom of the upper guide plate of the adjacent reoxygenation combination tank and the lower sewage tank.
[0017] This utility model has the following beneficial effects: 1. This utility model adopts an innovative structure of multi-layer reoxygenation combination tanks with tower-shaped support stacking. Through the coordinated design of multi-stage diversion pipes and sewage tanks, the traditional horizontal layout of aeration tanks is transformed into a vertically stacked modular design. This not only significantly reduces the footprint, but also utilizes the gravity difference of the sewage itself to form a "upstream + downstream" circulating three-dimensional reoxygenation exchange process. There is no need to set up additional high-power power equipment such as blowers and high-speed impellers. The theoretical energy consumption is close to the "liquid phase transport limit", which is far lower than traditional aeration technology. At the same time, only an inlet pipe, diversion pipe and simple diversion facilities (such as overflow weir and diversion cloth) are needed to realize upstream and downstream exchange. There is no need for complex underwater aeration pipelines (such as bubble lifting technology) or multi-stage reservoir scheduling systems (such as cascade reservoir technology), which significantly reduces the difficulty of equipment installation, construction and subsequent maintenance.
[0018] 2. This invention utilizes a multi-layer reoxygenation combined tank with a vertical exchange mechanism between the upper and lower layers. It employs an internal liquid-phase circulation of high-oxygen surface water and low-oxygen deep water (based on Bernoulli's low-energy theory) to break down the "surface-deep water exchange" into a "multi-stage vertical exchange." Wastewater in each layer of the reoxygenation combined tank circulates through a cycle of "upstream flow → downstream guide plate → stagnation on the guide plate → transport to the lower layer via the guide pipe." This extends the contact time and area between wastewater and air, avoiding the high-energy consumption of traditional blower aeration (gas-phase transport) or surface aeration (mechanical stirring). Simultaneously, filling the wastewater tank with filler layers such as ceramsite and activated carbon increases the water-air-microorganism contact area, effectively improving reoxygenation mass transfer efficiency. In particular, the overflow facility of the wastewater tank, combined with flexible hydrophilic guide wires / cloths at the edges, can evenly guide the upper layer of wastewater to overflow onto the guide plate, preventing short-circuiting of the water flow and effectively extending the contact time and area between wastewater and air, further enhancing reoxygenation mass transfer efficiency.
[0019] 3. This invention uses a guide pipe to directionally transport oxygen-enriched water from the upper reoxygenation tank to the bottom central area of the lower wastewater tank, forming a vertical flow path from top to bottom. This directly breaks down the thermocline and other stratified structures, promoting thorough mixing of deep water and surface high-oxygen water, thus specifically addressing the problem of oxygen deficiency in deep water. Compared to cascade reservoir technology and biological-physical synergistic enhancement technology (which require mixing cycles of several days to weeks), this invention, through forced upstream and downstream exchange, can complete deep water reoxygenation in a short time (several hours to one day). In particular, the installation of a drain pipe and drain valve at the bottom of the wastewater tank allows for the periodic discharge of deposited sludge (such as suspended solids or particulate pollutants in industrial wastewater). The packing layer not only enhances mass transfer but also adsorbs and degrades organic matter, achieving an integrated function of "reoxygenation-degradation-sludge discharge." This is more efficient than biological-physical synergistic technology (which relies solely on indirect action by plants or microorganisms), making it especially suitable for applications with high requirements, such as industrial wastewater treatment.
[0020] 4. The modular combination structure of the multi-layer reoxygenation combined tank and the tower-shaped support of this utility model not only allows for flexible expansion of the number of layers of the reoxygenation combined tank through the tower-shaped support (such as increasing or decreasing the number of layers according to the treatment scale) to adapt to the needs of different scales of sewage treatment; moreover, each layer of the reoxygenation combined tank is independently set on the tower-shaped support to form a structure, which can avoid the excessive strength requirements of the guide plate and sewage treatment tank of the traditional layer-by-layer stacking, and also reduces the difficulty of leveling during installation; in addition, the modular combination structure is also easy to maintain, and the tower-shaped support can reduce the number of ventilation holes compared with the traditional closed reoxygenation tower, thereby simplifying the structure; at the same time, the guide pipes are set up independently in multiple places to avoid the system failure problem caused by the blockage of a single pipe, thus improving the stability of operation.
[0021] In summary, this utility model has made significant progress in simplifying the structure, reducing energy consumption, improving mass transfer efficiency, and adapting to industrial wastewater through a vertical upflow and downflow exchange mechanism and modular structural design. It effectively solves the problems of high aeration energy consumption, complex structure, and poor deep water reoxygenation effect in the prior art. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is an enlarged view of the reoxygenation combined tank structure of this utility model; Figure 3 for Figure 2 Top view; In the diagram: 1-tower-shaped support, 2-sewage tank, 3-guide plate, 4-guide pipe, 5-inlet pipe, 6-outlet pipe, 7-guide cloth. Detailed Implementation
[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this does not limit the present invention in any way. Any changes or improvements made based on the teachings of the present invention shall fall within the protection scope of the present invention.
[0024] like Figure 1 , 2 As shown in Figure 3, the multi-stage upflow and downflow reoxygenation wastewater treatment tank of this utility model includes a tower-shaped support 1, a reoxygenation combination tank, a guide pipe 4, an inlet pipe 5, and an outlet pipe 6. The tower-shaped support 1 is stacked and fixed with multiple layers of reoxygenation combination tanks from top to bottom. The reoxygenation combination tank includes a wastewater tank 2 and a guide plate 3. The wastewater tank 2 is vertically arranged in the guide plate 3. The outlet of the inlet pipe 5 extends to the wastewater tank 2 of the top layer of the reoxygenation combination tank of the tower-shaped support 1. The inlet of the outlet pipe 6 is connected to the bottom end of the guide plate 3 of the bottom layer of the reoxygenation combination tank of the tower-shaped support 1. The inlet of the guide pipe 4 is connected to the bottom end of the upper layer guide plate 3 of the adjacent reoxygenation combination tank. The outlet of the guide pipe 4 extends to the lower layer wastewater tank 2 of the adjacent reoxygenation combination tank.
[0025] The outlets of the inlet pipe 5 and the guide pipe 4 extend to the bottom central area of the corresponding sewage tank 2. The sewage in the sewage tank 2 of the reoxygenation combination tank overflows from the overflow facility (not shown in the figure) at the top of the sewage tank 2 into the guide plate 3.
[0026] The wastewater tank 2 and the guide plate 3 of the reoxygenation combination tank are both set horizontally. The planar dimension of the guide plate 3 of the reoxygenation combination tank is larger than the planar dimension of the wastewater tank 2, and the height of the guide plate 3 of the reoxygenation combination tank is smaller than the height of the wastewater tank 2.
[0027] The overflow facility is a thin-walled overflow weir, a triangular overflow weir, or an overflow hole. The bottom of the sewage tank 2 is also provided with a sewage pipe and a sewage valve (not shown in the figure) that penetrate the corresponding guide plate 3.
[0028] The sewage tank 2 is filled with a packing layer composed of ceramsite, activated carbon and / or volcanic rock (not shown in the figure), and the outlets of the inlet pipe 5 and the guide pipe 4 extend to the bottom or the central area below the packing layer.
[0029] The overflow facility of the sewage tank 2 is fixedly provided with several guide wires (not shown in the figure) or a guide cloth 7 is fixedly laid on the outer edge of the overflow facility. The sewage in the sewage tank 2 flows down along the guide wires or the guide cloth 7 into the corresponding guide plate 3.
[0030] The non-connected parts of the guide wires or guide cloth 7 on the sewage tank 2 are not attached to the outer wall of the sewage tank 2, and the guide wires and guide cloth 7 are both made of flexible hydrophilic materials.
[0031] The overflow facility edge of the sewage tank 2 protrudes outward, and the guide wire or guide cloth 7 is fixedly connected to the outwardly protruding overflow facility edge of the sewage tank 2 and extends downward.
[0032] The portion of the guide cloth 7 outside the sewage tank 2 is inclined or arc-shaped, forming a downward hanging extension.
[0033] In this invention, at least two independent guide pipes 4 are provided between the bottom end of the upper guide plate 3 of the adjacent reoxygenation combined tank and the lower sewage tank 2.
[0034] The tower-shaped support 1 contains at least three layers of reoxygenation combination tanks stacked and fixed from top to bottom.
[0035] The working principle and process of this utility model: like Figure 1 , 2As shown in Figure 3, during operation, firstly, wastewater is introduced through the inlet pipe 5 into the bottom or lower central area of the packing layer (not shown in the figure) of the wastewater tank 2 in the top layer of the reoxygenation combination tank of the tower-shaped support 1. Subsequently, the wastewater rises from the bottom of the wastewater tank 2, increasing dissolved oxygen by contacting air horizontally when it reaches the surface. Then, the wastewater overflows from the overflow facility (not shown in the figure) at the top of the wastewater tank 2 under its own gravity and flows down along the guide wire (not shown in the figure) or guide cloth 7 into the guide plate 3. During the fall, the wastewater also increases dissolved oxygen by contacting air vertically. Subsequently, the wastewater falling into the guide plate 3 further increases dissolved oxygen by contacting air horizontally, thus realizing a three-dimensional reoxygenation process of vertical flow. Next, the wastewater enters from the inlet of the guide pipe 4 at the bottom of the guide plate 3 and is guided to the bottom or lower central area of the packing layer in the wastewater tank 2 of the lower reoxygenation combination tank, repeating the three-dimensional reoxygenation process of the upper reoxygenation combination tank. The above process is repeated multiple times to achieve a three-dimensional reoxygenation cycle, significantly improving the reoxygenation and mass transfer efficiency of the wastewater. Finally, the wastewater is discharged from the bottom of the guide plate 3 of the bottom reoxygenation combination tank through the outlet pipe 6, completing the reoxygenation process of the wastewater in the multi-stage up-and-down reoxygenation wastewater treatment tank of this invention. After the multi-stage up-and-down reoxygenation wastewater treatment tank has been working for a certain period of time, the drain valve at the bottom of the wastewater tank 2 can be opened to discharge the accumulated sediment in the wastewater tank 2 through the drain pipe. This restores the effective volume of the wastewater tank 2 and prevents the sediment in the wastewater tank 2 from overflowing into the guide plate 3 and affecting the reoxygenation effect.
[0036] The above description is merely a preferred embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.
Claims
1. A multi-stage upflow and downflow reoxygenation wastewater treatment tank, characterized in that: The system includes a tower-shaped support (1), a reoxygenation combination tank, a guide pipe (4), an inlet pipe (5), and an outlet pipe (6). The tower-shaped support (1) is stacked and fixed with multiple layers of reoxygenation combination tanks from top to bottom. The reoxygenation combination tank includes a sewage tank (2) and a guide plate (3). The sewage tank (2) is vertically set in the guide plate (3). The outlet of the inlet pipe (5) extends to the sewage tank (2) of the top reoxygenation combination tank of the tower-shaped support (1). The inlet of the outlet pipe (6) is connected to the bottom end of the guide plate (3) of the bottom reoxygenation combination tank of the tower-shaped support (1). The inlet of the guide pipe (4) is connected to the bottom end of the upper guide plate (3) of the adjacent reoxygenation combination tank. The outlet of the guide pipe (4) extends to the lower sewage tank (2) of the adjacent reoxygenation combination tank.
2. The multi-stage upflow-downflow reoxygenation sewage treatment tank according to claim 1, wherein: The outlets of the inlet pipe (5) and the guide pipe (4) extend to the bottom central area of the corresponding sewage tank (2). The sewage in the sewage tank (2) of the reoxygenation combination tank overflows from the overflow facility at the top of the sewage tank (2) into the guide plate (3).
3. The multi-stage upflow-downflow reoxygenation sewage treatment tank according to claim 2, wherein: The wastewater tank (2) and the guide plate (3) of the reoxygenation combination tank are both set horizontally. The planar dimension of the guide plate (3) of the reoxygenation combination tank is larger than that of the wastewater tank (2), and the height of the guide plate (3) of the reoxygenation combination tank is smaller than that of the wastewater tank (2).
4. The multi-stage upflow-downflow reoxygenation sewage treatment tank according to claim 2, wherein: The overflow facility is a thin-walled overflow weir, a triangular overflow weir, or an overflow hole. The bottom of the sewage tank (2) is also provided with a sewage pipe and a sewage valve that penetrate the corresponding guide plate (3).
5. The multi-stage upflow-downflow oxygenated sewage treatment tank according to claim 2, wherein: The sewage tank (2) is filled with a packing layer composed of ceramsite, activated carbon and / or volcanic rock, and the outlets of the inlet pipe (5) and the guide pipe (4) extend to the bottom or the central area below the packing layer.
6. The multi-stage upflow-downflow oxygenated sewage treatment tank according to claim 2, 3, 4 or 5, wherein: The overflow facility of the sewage tank (2) is fixedly provided with several guide wires or fixedly laid with guide cloth (7) along the circumferential direction on the outer edge of the overflow facility. The sewage in the sewage tank (2) flows down along the guide wires or guide cloth (7) to the corresponding guide plate (3).
7. The multi-stage upflow-downflow oxygenated sewage treatment tank according to claim 6, wherein: The non-connecting parts of the guide wires or guide cloth (7) on the sewage tank (2) are not attached to the outer wall of the sewage tank (2), and the guide wires and guide cloth (7) are both made of flexible hydrophilic materials.
8. The multi-stage upflow-downflow oxygenated sewage treatment tank according to claim 7, wherein: The overflow facility edge of the sewage tank (2) protrudes outward, and the guide wire or guide cloth (7) is fixedly connected to the outwardly protruding overflow facility edge of the sewage tank (2) and extends downward.
9. The multi-stage upflow-downflow oxygenation sewage treatment tank according to claim 7, wherein: The portion of the guide cloth (7) outside the sewage tank (2) is inclined or arc-shaped to form a downward hanging extension.
10. The multi-stage upflow-downflow oxygenation sewage treatment tank according to claim 6, wherein: At least two independent guide pipes (4) are provided between the bottom of the upper guide plate (3) of the adjacent reoxygenation combination tank and the lower sewage tank (2).