A vortex street type high-efficiency energy-saving aeration tank

Abstract

The application discloses a vortex high-efficiency energy-saving aeration tank, which comprises an aeration wall and a flow guide wall inside the aeration wall, an aeration tank gallery is formed between the aeration wall and the flow guide wall, and at least one of the aeration wall and the flow guide wall is provided with a wave-shaped flow guide structure located in the aeration tank gallery. The application has the beneficial effects that the air bubble movement path is changed from the traditional vertical upward movement to three-dimensional spiral movement, the residence time of air in seawater after desulfurization is greatly prolonged, the air-liquid contact area is increased, and the oxygen mass transfer efficiency and the CO2 stripping efficiency can be increased by more than 25% compared with the traditional aeration mode; the aeration branch pipes are arranged in the concave surface of the wave trough, the number is reduced by about 40% compared with the traditional full coverage arrangement, the pipe network structure and the aeration tank area are effectively simplified (more than 20% is saved compared with the traditional rectangular aeration tank), and the installation and maintenance costs are reduced.

Description

Technical Field

[0001] This application belongs to the field of water treatment technology, specifically relating to a vortex-type high-efficiency energy-saving aeration tank. Background Technology

[0002] Seawater-based flue gas desulfurization (FGD) technology has become the preferred desulfurization process for coastal power plants due to its readily available resources, low operating costs, and lack of solid waste generation. However, the pH of the desulfurized seawater is significantly reduced, and it contains a large amount of unstable sulfite (SO32-). 2- Direct discharge of pollutants poses a threat to marine ecosystems. Therefore, it is essential to equip the marine environment with a seawater quality restoration system, the core of which is aeration treatment, designed to restore the water quality to discharge standards.

[0003] However, in acidic environments, SO3 2- It easily decomposes and releases SO2 gas (Equation 1), causing secondary pollution and seriously affecting the environmental benefits of this process. By aeration and oxygenation, SO3 can be... 2- Oxidized to the stable sulfate ion (SO4). 2- (Equation 2) thus completely prevents SO2 from escaping. Furthermore, aeration can remove excess dissolved CO2 produced by neutralization reactions in seawater, promote pH recovery, and increase dissolved oxygen (DO) concentration, comprehensively restoring seawater quality indicators. The formula is as follows: (Equation 1); (Equation 2).

[0004] Currently, the aeration tanks widely used in water quality restoration are generally rectangular in structure, which suffer from problems such as short bubble rise paths, insufficient residence time, low gas-liquid mass transfer efficiency, high energy consumption, and easy clogging of aeration pipes. Based on this, patent CN203461875U uses a combination of vortex fans and jet aerators to reduce the energy consumption of the aeration system; however, it is only suitable for low back pressure conditions with small water storage, limiting its treatment scale. Patent CN113429025B uses a multi-layer aeration pipe network along the depth of the aeration tank to adapt to tidal changes, ensuring treatment effectiveness at high tide, but the system structure is complex and installation and maintenance costs are high.

[0005] Therefore, there is an urgent need to develop a new type of aeration tank with a reasonable structure and high operating efficiency, which can improve gas-liquid contact efficiency and oxidation effect, reduce aeration energy consumption and simplify maintenance, thereby enhancing the overall performance and economy of seawater desulfurization process. Summary of the Invention

[0006] The purpose of this application is to provide a vortex-type high-efficiency and energy-saving aeration tank, which aims to effectively improve mass transfer efficiency, reduce system energy consumption, simplify aeration structure, and achieve efficient and reliable aeration treatment by actively controlling the fluid morphology in the tank and optimizing the movement path and residence time of aeration bubbles in the water. This solves the problems of low gas-liquid mass transfer efficiency, high energy consumption, and complex aeration pipe network structure that are common in existing aeration technologies.

[0007] The objective of this application is achieved through the following technical solution: A vortex-type high-efficiency energy-saving aeration tank includes an aeration wall and a flow guide wall inside the aeration wall. An aeration tank corridor is formed between the aeration wall and the flow guide wall. At least one of the aeration wall and the flow guide wall is provided with a wave-shaped flow guide structure located in the aeration tank corridor.

[0008] Furthermore, the aeration wall is rectangular, and the guide walls are arranged alternately along both sides.

[0009] Furthermore, the aeration tank corridor forms a continuous S-shaped corridor.

[0010] Furthermore, the aeration wall is a straight flow guide structure, while the flow guide wall is a wave-shaped flow guide structure.

[0011] Furthermore, the aeration wall and / or guide wall are provided with a flow promoter, which is arranged along the flow direction of the aeration tank corridor.

[0012] Furthermore, the aeration wall and / or guide wall are provided with aeration components, and the aeration holes of the aeration components are located in the troughs of the wave-shaped guide structure.

[0013] Furthermore, the aeration assembly includes aeration branch pipes, aeration blowers, air-gathering pipes, and aeration main pipes. Several aeration blowers are connected to air-gathering pipes, air-gathering pipes are connected to several aeration main pipes, and aeration main pipes are connected to several aeration branch pipes. Aeration holes are provided on the aeration branch pipes.

[0014] Furthermore, the wave shape of the wave-shaped flow guide structure is an involute or a sine curve.

[0015] Furthermore, when the water flow in the aeration tank corridor encounters the trough of the wave-shaped guide structure, the streamlines bend, and a stable, horizontal vortex flow field is naturally formed behind each trough. The vortex flow field captures the bubbles released by the aeration components, causing the bubbles to move in a three-dimensional spiral upward motion.

[0016] Furthermore, the trajectory of the bubble's three-dimensional spiral upward motion satisfies the following equation: ; in, For the bubble movement path, Where is the vortex radius. The vortex angular velocity, This represents the rising speed of the bubble.

[0017] This application utilizes the synergistic effect of a wave-shaped flow guide structure and directional water flow to create a stable vortex flow field within the aeration tank, resulting in the following significant beneficial effects: (1) Mass transfer efficiency is significantly improved. The bubble movement path changes from the traditional vertical upward movement to a three-dimensional spiral movement, which greatly prolongs the residence time of air in the desulfurized seawater and increases the gas-liquid contact area. The oxygen mass transfer efficiency and CO2 stripping efficiency can be improved by more than 25% compared with the traditional aeration method.

[0018] (2) System structure and energy consumption optimization. The aeration branch pipes are centrally arranged on the concave surface of the wave trough, reducing the number by about 40% compared to the traditional full-coverage arrangement, effectively simplifying the pipe network structure and the floor space of the aeration tank (saving more than 20% compared to the traditional rectangular aeration tank), and reducing installation and maintenance costs. Combined with conventional centrifugal fans and non-frequency conversion motors, energy-saving operation is achieved while ensuring performance.

[0019] (3) Enhanced operational reliability and adaptability. The vortex flow field enables spontaneous retention and uniform diffusion of bubbles, effectively avoiding local accumulation and aeration pipe blockage. The system operates stably and is especially suitable for ships and coastal power plants.

[0020] The aforementioned main solution and its various further alternatives can be freely combined to form multiple solutions, all of which are solutions that can be adopted and are claimed in this application; furthermore, the (non-conflicting alternatives) can also be freely combined with each other and with other alternatives. Those skilled in the art, after understanding the solution of this application, will realize from the prior art and common general knowledge that there are many combinations, all of which are technical solutions to be protected by this application, and will not be exhaustively listed here. Attached Figure Description

[0021] Figure 1 This is a structural diagram of this application.

[0022] Figure 2 This is a top view of the structure of this application.

[0023] In the diagram: 1-Aeration wall, 2-Flow booster, 3-Flow guide wall, 4-Aeration branch pipe, 5-Aeration blower, 6-Air gathering pipe, 7-Aeration main pipe. Detailed Implementation

[0024] The following non-limiting embodiments are used to illustrate this application.

[0025] Example 1 refer to Figure 1 and Figure 2As shown, a vortex-type high-efficiency energy-saving aeration tank includes an aeration wall 1, a flow promoter 2, a flow guide wall 3, an aeration branch pipe 4, an aeration blower 5, an air-gathering pipe 6, and an aeration main pipe 7.

[0026] Aeration wall 1 is the enclosure structure outside the aeration tank, and flow guide wall 3 is the horizontal barrier structure inside the aeration tank. Flow guide wall 3 is located inside aeration wall 1, and an aeration tank corridor is formed between aeration wall 1 and flow guide wall 3. Water flows into the aeration tank corridor and undergoes aeration treatment in the aeration tank corridor.

[0027] The aeration wall 1 is rectangular, meaning the overall outline of the aeration tank is rectangular. Several guide walls 3 are arranged alternately along both sides. That is, one guide wall 3 is arranged on one side of the aeration wall 1, and a corridor space is reserved between the end of the guide wall 3 and the aeration wall 1 on the opposite side. Another adjacent guide wall 3 is arranged on the aeration wall 1 on the opposite side, and a corridor space is reserved between the end of the guide wall 3 and the aeration wall 1 on one side.

[0028] The aeration tank corridor forms a continuous S-shaped channel, increasing the flow path of the water and ensuring sufficient aeration within the tank. Preferably, the direction of the guide wall 3 is parallel to the inflow and outflow directions of the water to ensure smooth flow and avoid excessive water resistance that could affect the aeration effect. Similarly, the shape of the aeration wall 1 and the arrangement of the guide wall 3 can also be adapted to form other types of corridor structures.

[0029] At least one of the aeration wall 1 and the guide wall 3 is provided with a wave-shaped guide structure located in the aeration tank corridor. That is, the wave-shaped guide structure can be arranged alone on the aeration wall 1, alone on the guide wall 3, or together on both the aeration wall 1 and the guide wall 3. Preferably, the aeration wall 1 is a straight guide structure and the guide wall 3 is a wave-shaped guide structure.

[0030] When the water flows forward under the drive of the propeller, it bends when it encounters the trough of the wave-shaped guide structure. A stable, horizontal vortex flow field is naturally formed behind each trough. This vortex can effectively capture the air bubbles released by the aeration components (aeration branch pipes) and make them move upward in a three-dimensional spiral.

[0031] A flow promoter 2 is installed on the aeration wall 1 and / or the guide wall 3. Multiple low-speed, large-blade flow promoters are installed in the aeration tank corridor to provide stable and continuous unidirectional power to the water in the aeration tank corridor, so that the water flows stably along the channel at a certain speed.

[0032] The flow booster 2 is arranged along the flow direction of the aeration tank corridor. That is, in the straight section of the aeration tank corridor, the flow booster 2 is arranged at the inlet of the straight section and parallel to the flow direction to accelerate the water flow. At the corner of the aeration tank corridor, the flow booster 2 is arranged at the inlet of the corner and tangent to the flow direction to achieve a smooth transition of the water flow.

[0033] Aeration components are provided on the aeration wall 1 and / or the guide wall 3. The aeration holes of the aeration components are located within the troughs of the corrugated guide structure. That is, the aeration branch pipes of the aeration components are concentrated at the concave surface of the trough of the corrugated guide structure, and several aeration holes are opened on the part of the aeration branch pipe perpendicular to the bottom of the aeration tank. Arranging the aeration holes within the troughs of the corrugated guide structure ensures that bubbles are effectively captured by the eddies.

[0034] The aeration assembly includes aeration branch pipes 4, aeration blowers 5, air-gathering pipes 6, and aeration main pipes 7. Several aeration blowers 5 are connected to the air-gathering pipes 6, and the air-gathering pipes 6 are supplied with air through the blowers. The air-gathering pipes 6 are connected to several aeration main pipes 7, and the air-gathering pipes 6 distribute the air to the aeration main pipes 7. The aeration main pipes 7 are connected to several aeration branch pipes 4. Aeration holes are opened on the aeration branch pipes 4, and the aeration branch pipes 4 perform secondary dispersion of the air to the aeration main pipes 7. Finally, the gas is discharged through the aeration holes.

[0035] Air from the aeration blower is collected in the air-gathering duct and then transported to the aeration branch pipes via the main aeration pipe. The portion of the aeration branch pipe located in the trough is perpendicular to the bottom of the pool, and this portion of the branch pipe has several aeration holes to achieve aeration at the trough. The air-gathering duct is preferably made of carbon steel or FRP, and its diameter should not be smaller than that of the main aeration pipe. The main aeration pipe is preferably made of FRP, PP, or PE, and its diameter should be larger than that of the aeration branch pipes.

[0036] The wave shape of the wave-shaped guide structure is an involute or sine curve, which is conducive to the formation of vortices. When the water flow in the aeration tank corridor encounters the trough of the wave-shaped guide structure, the streamlines bend, and a stable, horizontal vortex flow field is naturally formed behind each trough. The vortex flow field captures the bubbles released by the aeration components (aeration branch pipes), causing the bubbles to move in a three-dimensional spiral upward motion.

[0037] The trajectory of the bubble's three-dimensional spiral upward motion satisfies the following equation: ; in, For the bubble movement path, Where is the vortex radius. The vortex angular velocity, S represents the bubble rising velocity. Compared to the simple vertical upward path of bubbles in a traditional aeration tank (denoted as H), S... H, thus significantly prolonging the bubble residence time, thereby improving mass transfer efficiency and aeration effect.

[0038] This embodiment can improve oxygen mass transfer efficiency and CO2 stripping efficiency by more than 25% compared with traditional aeration methods, reduce the number of aeration branch pipes by about 40% compared with traditional full-coverage layout, and save more than 20% of the floor space compared with traditional rectangular aeration tank.

[0039] Implementation Case 1 Taking a 2×300MW coal-fired unit as an example, the seawater restoration system adopts a vortex-type high-efficiency energy-saving aeration tank (25m wide × 30m long) as described in Example 1, for reference. Figure 1 and Figure 2 As shown, the structure mainly consists of two interconnected U-shaped aeration tank corridors forming an S-shape, with either a guide wall 3 or an aeration wall 1 on either side. The guide wall 3 has a wave-shaped guide structure. The aeration tank corridors are equipped with four sets of low-speed, large-blade propellers 2, each with a power of 1.5kW, an impeller diameter of 1000mm, and a rotational speed of 50rpm, used to drive the water to flow steadily forward at a speed of approximately 0.3m / s.

[0040] The aeration system consists of two aeration blowers (centrifugal blowers, each with an air volume of 25,000 Nm³). 3 The system consists of a duct (6, DN1000, carbon steel), three main aeration pipes (7, DN600, FRP), and 54 branch aeration pipes (4, DN200, PP). The branch aeration pipes are centrally located on the concave surface of the corrugated guide wall, and the pipe walls have several aeration holes with a diameter of 3 mm.

[0041] Acidic seawater from the desulfurization absorption tower flows by gravity into the aeration tank, completing water quality restoration. During this process, air blown in by the aeration blower is collected through the air-gathering pipe, transported through the main aeration pipe, and finally released as uniform microbubbles through the aeration branch pipes and aeration holes at the troughs. Simultaneously, the directional water flow driven by the thruster forms a controllable vortex street as it passes through the corrugated wall, entraining these bubbles into a three-dimensional spiral motion trajectory. This greatly enhances the gas-liquid mass transfer process and prolongs the residence time of the bubbles in the desulfurized seawater, reducing residual sulfite (SO32-) in the water. 2- It is efficiently oxidized to stable sulfate (SO4). 2- Simultaneously, excess dissolved CO2 is stripped away, restoring the seawater's pH and dissolved oxygen concentrations, allowing it to be discharged after meeting treatment standards. SO3 2- Both oxidation efficiency and CO2 stripping efficiency reached over 98%, and no short-circuiting or dead zone phenomena were found.

[0042] Comparison Case 1 A traditional rectangular aeration tank (30m wide × 40m long) was used to treat the seawater after desulfurization from the aforementioned coal-fired power unit for water quality restoration. The water flow rate was the same as above. An aeration pipe network (90 branch pipes) was evenly laid on the bottom of the tank. The air bubbles rose vertically in the water, with a short rising path (approximately equal to the effective water depth) and a residence time of approximately 90 seconds. SO3... 2- The oxidation efficiency is less than 92%. To achieve emission standards, a higher air-to-water ratio and a longer tank volume are required, resulting in energy consumption and construction costs increasing by more than 30% compared to vortex-type high-efficiency energy-saving aeration tanks. At the same time, its dense pipe network layout increases the risk of blockage and maintenance difficulty.

[0043] The foregoing basic examples and their further alternative examples can be freely combined to form multiple embodiments, all of which are embodiments that can be adopted and claimed in this application. In the scheme of this application, each alternative example can be arbitrarily combined with any other basic example and alternative example.

[0044] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A vortex-type high-efficiency energy-saving aeration tank, comprising an aeration wall (1) and a flow guide wall (3) inside the aeration wall (1), characterized in that: An aeration tank corridor is formed between the aeration wall (1) and the guide wall (3), and at least one of the aeration wall (1) and the guide wall (3) is provided with a wave-shaped guide structure located in the aeration tank corridor.

2. The vortex-type high-efficiency energy-saving aeration tank according to claim 1, characterized in that: The aeration wall (1) is rectangular, and the guide wall (3) is arranged in a crisscross pattern along both sides.

3. The vortex-type high-efficiency energy-saving aeration tank according to claim 1 or 2, characterized in that: The aeration tank corridor forms a continuous S-shaped corridor.

4. The vortex-type high-efficiency energy-saving aeration tank according to claim 1, characterized in that: The aeration wall (1) is a straight flow guide structure, and the flow guide wall (3) is a wave-shaped flow guide structure.

5. The vortex-type high-efficiency energy-saving aeration tank according to claim 1, characterized in that: The aeration wall (1) and / or the guide wall (3) are provided with a flow promoter (2), which is arranged along the flow direction of the aeration tank corridor.

6. The vortex-type high-efficiency energy-saving aeration tank according to claim 1, characterized in that: The aeration wall (1) and / or the guide wall (3) are provided with aeration components, and the aeration holes of the aeration components are located in the trough of the wave-shaped guide structure.

7. The vortex-type high-efficiency energy-saving aeration tank according to claim 6, characterized in that: The aeration assembly includes aeration branch pipes (4), aeration blowers (5), air-gathering pipes (6) and aeration main pipes (7). Several aeration blowers (5) are connected to air-gathering pipes (6), air-gathering pipes (6) are connected to several aeration main pipes (7), and aeration main pipes (7) are connected to several aeration branch pipes (4). Aeration holes are provided on the aeration branch pipes (4).

8. The vortex-type high-efficiency energy-saving aeration tank according to claim 1, characterized in that: The wave shape of the wave-shaped flow guide structure is an involute or a sine curve.

9. The vortex-type high-efficiency energy-saving aeration tank according to claim 1 or 8, characterized in that: When the water flow in the aeration tank corridor encounters the trough of the wave-shaped guide structure, the streamlines bend, and a stable, horizontal vortex flow field is naturally formed behind each trough. The vortex flow field captures the bubbles released by the aeration components, causing the bubbles to move in a three-dimensional spiral upward motion.

10. The vortex-type high-efficiency energy-saving aeration tank according to claim 9, characterized in that: The trajectory of the bubble's three-dimensional spiral upward motion satisfies the following equation: ； in, For the bubble movement path, Where is the vortex radius. The vortex angular velocity, This represents the rising speed of the bubble.

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