Air floatation apparatus of a motorless stirring system

Abstract

The utility model discloses a kind of air flotation equipment of motorless stirring system, it is related to sewage treatment technology, including flocculator, air flotation tank, the inclined stirring paddle of flocculator bottom is equipped, there is guide vane in pool;Air flotation tank has partition, collection tank, overflow and slag scraper, sewage and reagent are guided to impact stirring paddle by guide vane, realize motorless stirring by water flow power, the flocculation body formed is combined with air bubble and floats up in air flotation tank, dross is scraped to collection tank by slag scraper, clean water is discharged from overflow.The equipment utilizes sewage self kinetic energy to drive stirring, without motor, reduce energy consumption and maintenance cost;Stirring paddle is inclined and partly exposed to liquid surface, cooperate with spiral guide channel, strengthen bottom mixing and prevent flocculation body from breaking, improve flocculation and air flotation effect, while rely on liquid level difference gravity flow, save additional conveying power, with energy-saving and efficient purification advantage.

Description

Technical Field

[0001] This utility model belongs to the field of wastewater treatment technology, and in particular relates to an air flotation device without a motor-driven stirring system. Background Technology

[0002] The flocculation and mixing zone of an air flotation (AF) system is a crucial step in achieving the coagulation of suspended particles in water. Its core function is to ensure that tiny suspended particles and colloidal particles in the water come into full contact with the added flocculant (such as PAC, PAM, etc.), forming larger flocs (flocs) through chemical adsorption and charge neutralization. This creates conditions for subsequent air flotation separation (where flocs float to the surface carried by air bubbles). The specific working process consists of three steps: First, the flocculant is initially mixed with the raw water in the initial rapid mixing zone, ensuring uniform dispersion of the agent and initiating the initial coagulation of particles. Next, after entering the flocculation and mixing zone, a slow and orderly water flow is formed by the mixing device (such as impellers and guide vanes), and the mixing intensity must be precisely controlled—too strong a mixing intensity will break up the already formed flocs, while too weak a mixing intensity will not provide sufficient opportunities for particle collision. Finally, under appropriate mixing intensity, tiny particles continuously collide and adsorb, gradually forming densely structured flocs with larger particle sizes (usually tens to hundreds of micrometers in diameter), allowing them to more effectively adhere to the air bubbles generated by the air flotation system and ultimately float to the surface to be scraped off.

[0003] Existing air flotation equipment has significant shortcomings in the coagulation and flocculation stages. Most agitators rely on motor drives, which not only increases energy consumption but also raises the failure rate and subsequent maintenance costs. More importantly, the agitators in traditional equipment are often installed in the upper middle part of the tank, resulting in poor mixing of the wastewater at the bottom. This leads to uneven mixing of the reagents and wastewater at the bottom, making it difficult for some suspended solids deposited at the bottom to fully contact the reagents, directly affecting the flocculation reaction efficiency and thus reducing the effectiveness of subsequent air flotation separation.

[0004] Existing electric mixing devices still have their agitators positioned too high in the middle, resulting in blind spots at the bottom of the tank. This fails to meet the requirements for efficient mixing, especially when treating oily wastewater or other wastewater containing heavy bottom pollutants. The inadequate mixing at the bottom is particularly pronounced, wasting reagents and failing to achieve the desired wastewater purification effect. Therefore, there is an urgent need for a flotation device with an agitator positioned at the bottom and without power drive, to solve the problems of insufficient bottom mixing, high energy consumption, and difficult maintenance. Utility Model Content

[0005] This utility model provides an air flotation device without a motor-driven stirring system, aiming to solve the problems of existing air flotation devices relying on motors for stirring, resulting in high energy consumption, difficult maintenance, and the fact that the stirring device is mostly located in the middle and upper part of the tank, leading to uneven mixing of sewage and chemicals at the bottom of the tank, which affects the flocculation and air flotation effect.

[0006] This utility model is implemented as follows: A flotation device without a motor-driven stirring system, 1. comprising a flocculation tank and a flotation tank, wherein the bottom of the flocculation tank is at the middle height of the flotation tank, and the bottom of the right side of the flocculation tank is connected to the flotation tank; an inlet and a chemical inlet are provided at the upper part of the flocculation tank; an inclined stirring paddle is provided at the bottom of the flocculation tank; and a guide plate is provided in the flocculation tank between the blade of the stirring paddle and the inlet and the chemical inlet to guide wastewater and chemical solution to drive the blade of the stirring paddle to rotate. A partition plate is vertically installed on the upper right side of the inner cavity of the flotation tank. A flow channel is formed between the bottom of the partition plate and the bottom of the inner wall of the flotation tank. A collection trough with an open top is installed on the left side of the partition plate. An overflow port is installed on the right side of the flotation tank. A scum scraper is installed at the top of the flotation tank, to the left of the collection trough, to scrape scum into the collection trough.

[0007] Preferably, the height of the collection tank opening is higher than the height of the overflow port.

[0008] Preferably, it also includes a booster pump, the outlet of which is connected to the inlet via a pipe.

[0009] Preferably, the collection tank is connected to a slag discharge pipe that extends to the outside of the flotation tank.

[0010] Beneficial effects Compared with the prior art, the beneficial effects of this utility model are as follows: This utility model provides an air flotation device with a motorless stirring system. The stirring paddle is inclinedly positioned at the bottom of the flocculation tank and equipped with a spiral guide channel adapted to the inlet water direction and pressure. The stirring paddle is driven to rotate by the impact force and kinetic energy of the wastewater itself. This not only specifically enhances the mixing effect at the bottom of the tank, avoiding the problem of bottom reagent sedimentation caused by traditional upper and middle stirring, but also ensures that the heavy oil or suspended solids at the bottom of the oily wastewater are in full contact with the reagent, improving flocculation efficiency. Furthermore, the 30°-60° tilt angle and the fact that half of the paddle blades are above the liquid surface further enhance the flocculation efficiency. The design creates a low-shear mixing environment, preventing flocs from being broken up and oil droplets from being over-emulsified, thus creating favorable conditions for subsequent air flotation separation and eliminating the need for additional processing steps due to uneven mixing or over-mixing. On the other hand, the mixing process does not require motor drive, and the sewage flows by gravity without power by relying on the liquid level difference between the flocculation tank and the air flotation tank. There is no need to set up an additional sewage transfer pump, which greatly reduces equipment energy consumption and reduces the daily maintenance requirements of power components such as motors and transfer pumps. This avoids downtime losses and maintenance costs caused by power equipment failure, achieving the dual goals of energy saving and consumption reduction and operating cost control. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of this utility model.

[0012] In the diagram: 1-flocculation tank, 2-air flotation tank, 3-, 4-inlet, 5-chemical inlet, 6-guide plate, 7-stirring paddle, 8-partition plate, 9-overflow outlet, 10-collection tank, 11-slag discharge pipe. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0014] Please see Figure 1 This utility model provides a technical solution: an air flotation device without a motor stirring system, including a flocculation tank 1 and an air flotation tank 2. The bottom of the flocculation tank 1 is at the middle height of the air flotation tank 2, and the bottom of the right side of the flocculation tank 1 is connected to the air flotation tank 2.

[0015] This height design ensures that the liquid level in flocculation tank 1 is always higher than that in flotation tank 2 (the liquid level difference is recommended to be controlled at 10-15mm). On the one hand, it prevents the backflow of wastewater containing microbubbles in flotation tank 2 into flocculation tank 1, preventing bubbles from interfering with the stable formation of flocs. On the other hand, it enables wastewater to flow by gravity without power by relying on the liquid level difference, eliminating the need for an additional transfer pump and reducing energy consumption. The guide plate 6 can prevent wastewater and chemical solution from directly impacting the inner wall of flocculation tank 1 and causing splashing, while ensuring that the fluid energy is concentrated on the agitator 7 to guarantee driving efficiency.

[0016] The upper part of the flocculation tank 1 is provided with an inlet 4 and a chemical inlet 5. The bottom of the flocculation tank 1 is provided with an inclined stirring paddle 7. Inside the flocculation tank 1, between the blades of the stirring paddle 7 and the inlet 4 and the chemical inlet 5, there is a guide plate 6 that guides the wastewater and chemical solution to the blades of the stirring paddle 7.

[0017] The stirring shaft of the stirring paddle 7 is connected to the bottom of the flocculation tank 1 via a bearing, which reduces frictional resistance and improves hydraulic drive efficiency. The stirring paddle 7 is made of 316 stainless steel. The stirring shaft of the stirring paddle 7 is inclined at a 30°-60° angle to the bottom of the flocculation tank 1, and half of the stirring paddle 7 is above the liquid surface.

[0018] The bearings are corrosion-resistant deep groove ball bearings; the 316 stainless steel material can withstand acidic and alkaline wastewater environments with pH values ​​of 3-11, avoiding corrosion of the blades by oily wastewater and chemical wastewater, and extending the service life of the equipment to 3-5 years; if the tilt angle is less than 30°, the contact area between the blades and the water flow is too small, and the kinetic energy of the water flow cannot drive the blades to rotate stably (it is easy for the speed to be lower than 5 r / min); if it is greater than 60°, most of the blades are submerged in the wastewater, and turbulence (turbulence intensity greater than 0.5 m / s) is easily generated during rotation, breaking up the already formed flocs; the design with half of the blades above the liquid surface can balance the driving force and stirring intensity, so that the blade speed is stabilized at 10-20 r / min, which not only meets the mixing requirements, but also protects the integrity of the flocs.

[0019] The agitator 7 has 2-4 blades, and the blade surface is provided with arc-shaped protrusions to enhance the propulsion of water flow.

[0020] The guide plate 6 is set at an angle, forming a guide channel above. The medicine inlet 5 and the water inlet 4 are set side by side, and the medicine outlet of the medicine inlet 5 faces the guide channel, so that the medicine enters the guide channel with the sewage and impacts the blades.

[0021] The distance between the drug inlet 5 and the water inlet 4 is 30-50mm. This design can realize the instant premixing of "drug-water" with a premixing uniformity of over 90%, avoiding the drug liquid from flowing into the bottom of the flocculation tank 1 alone and causing sedimentation (the amount of sedimentation can be reduced by 80%). At the same time, the synchronous impact of the impeller blades allows the premixed liquid to form a preliminary mixing system before stirring, shortening the flocculation reaction time.

[0022] Inlet 4 receives wastewater with a pressure of 0.1-0.3 MPa, and the inlet direction is consistent with the tangential direction of the guide channel in the flocculation tank 1. The guide channel formed by the guide plate 6 is spiral-shaped, and the spiral angle matches the 0.1-0.3 MPa pressure of inlet 4 to avoid excessive turbulence in the water flow.

[0023] A partition plate 8 is vertically installed on the upper right side of the inner cavity of the flotation tank 2. A flow channel is formed between the bottom of the partition plate 8 and the bottom of the inner wall of the flotation tank 2. A collection tank 10 with an open top is installed on the left side of the partition plate 8. An overflow port 9 is installed on the right side of the flotation tank 9. A scum scraper 12 is installed on the top of the flotation tank 2, to the left of the collection tank 10, to scrape the scum into the collection tank 10.

[0024] In this embodiment, the width of the scraper blade of the scum scraper 12 is adapted to the width of the flotation tank 2, and the operating speed is 0.5-1m / min. The scraping speed can be adjusted according to the thickness of the scum. When the thickness of the scum is >50mm, the speed is adjusted to 1m / min to avoid scum accumulation. When the thickness of the scum is <20mm, the speed is adjusted to 0.5m / min to reduce the amount of clean water carried.

[0025] Furthermore, the height of the opening of the collection tank 10 is higher than the height of the overflow port 9. A slag discharge pipe 11 that extends through the collection tank 10 to the outside of the flotation tank 2 is connected to the collection tank 10.

[0026] In this embodiment, the height difference between the opening of the collection tank 10 and the overflow port 9 is 5-10mm. This height difference ensures that the scum scraped by the scum scraper 12 completely enters the collection tank 10, preventing the scum from overflowing from the edge due to the low opening (the overflow flow can be reduced by 95%), and is discharged from the overflow port 9 with the clean water; the scum discharge pipe 11 has a diameter of 80-120mm and is made of 316 stainless steel.

[0027] Furthermore, it also includes a booster pump 3, whose outlet is connected to the inlet 4 via a pipeline, pressurizing the sewage to 0.1-0.3 MPa before sending it into the flocculation tank 1.

[0028] The working principle and usage process of this utility model are as follows: After the utility model is installed, the booster pump 3 is started to pressurize the sewage to 0.1-0.3 MPa. The sewage flows into the flocculation tank 1 from the inlet 4. At the same time, flocculant is added into the guide channel through the inlet 5. After the sewage and the chemical solution are initially mixed in the guide channel, they impact the blades of the stirring paddle 7 tangentially along the spiral channel, causing the stirring paddle 7 to rotate around the bearing. The rotating blades create an upward vortex on the sewage and chemical solution at the bottom of the flocculation tank 1, causing the sediment at the bottom to settle. Suspended solids come into full contact with the chemical solution to form flocs. Wastewater that has completed the flocculation reaction flows into flotation tank 2 from the bottom right side of flocculation tank 1 due to the liquid level difference between flocculation tank 1 and flotation tank 2. The flocs in the wastewater combine with the microbubbles generated in flotation tank 2 and float to the surface with the bubbles to form scum. The scum scraper 12 is started to scrape the scum on the surface of the liquid into the collection tank 10 and discharge it through the scum discharge pipe 11. The clean water after removing the scum flows to the right side along the flow channel at the bottom of flotation tank 2 and is finally discharged from the overflow port 9, completing the wastewater purification process.

[0029] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A flotation device without an electric stirring system, comprising a flocculation tank (1) and a flotation tank (2), characterized in that: The bottom of the flocculation tank (1) is at the middle height of the flotation tank (2), and the bottom right side of the flocculation tank (1) is connected to the flotation tank (2). The upper part of the flocculation tank (1) is provided with an inlet (4) and a chemical inlet (5). The bottom of the flocculation tank (1) is provided with an inclined stirring paddle (7). Inside the flocculation tank (1), between the blade of the stirring paddle (7) and the inlet (4) and the chemical inlet (5), there is a guide plate (6) that guides the wastewater and chemical solution to the blade of the stirring paddle (7) to drive the blade to rotate. A partition plate (8) is vertically installed on the upper right side of the inner cavity of the flotation tank (2). A flow channel is formed between the bottom of the partition plate (8) and the bottom of the inner wall of the flotation tank (2). A collection tank (10) with an open top is installed on the left side of the partition plate (8). An overflow port (9) is installed on the right side of the flotation tank (2). A scum scraper (12) is installed on the top of the flotation tank (2) on the left side of the collection tank (10) to scrape scum into the collection tank (10).

2. The air flotation device with a motorless stirring system as described in claim 1, characterized in that: The height of the collection trough (10) opening is higher than the height of the overflow port (9).

3. The air flotation device with a motorless stirring system as described in claim 1, characterized in that: It also includes a booster pump (3), the outlet of which is connected to the inlet (4) via a pipe.

4. The air flotation device with a motorless stirring system as described in claim 1, characterized in that: The collection tank (10) is connected to a slag discharge pipe (11) that extends to the outside of the flotation tank (2).

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