An air flotation device and a sewage treatment system

Abstract

The present application discloses a flotation device and a sewage treatment system, relating to the technical field of sewage treatment. The flotation device includes a bubble generation unit, a three-phase vortex mixing unit, a contact tank and a flotation tank that are connected in sequence; the three-phase vortex mixing unit is connected to a sewage water source and a compressed air source, and the three-phase vortex mixing unit is used for performing three-phase vortex mixing on sewage to generate flocculants; the output end of the bubble generation unit is communicated with the contact tank and is also communicated with the output end of the three-phase vortex mixing unit; the bubble generation unit is used for conveying a water body with bubbles to the output end of the three-phase vortex mixing unit. The sewage treatment system includes the above-mentioned flotation device. The flotation device provided by the present application can achieve the rapid floating of flocculants and improve the purification efficiency.

Description

Technical Field

[0001] This application relates to the technical field of sewage treatment, and particularly to a flotation device and a sewage treatment system. Background Art

[0002] In the flotation treatment of sewage purification, solid or liquid pollutants in the sewage are attached to bubbles, and under the action of buoyancy, they float to the surface of the sewage, thereby removing the pollutants in the sewage.

[0003] However, in the existing flotation devices, when treating sewage, the rising speed of the bubbles is slow, which affects the working efficiency of sewage purification and results in a low sewage purification efficiency. Summary of the Invention

[0004] This application provides a flotation device and a sewage treatment system to increase the rising speed of flocs and thus improve the sewage purification speed.

[0005] To solve the above problems, this application provides:

[0006] A flotation device, comprising a three-phase eddy current mixing unit, a contact tank, a flotation tank, and a bubble generating unit, wherein the three-phase eddy current mixing unit, the contact tank, and the flotation tank are connected in sequence;

[0007] The three-phase eddy current mixing unit is connected to a sewage water source and a compressed air source, and is used for performing three-phase eddy current mixing on the sewage to generate flocs;

[0008] The output end of the bubble generating unit is communicated with the contact tank and is also communicated with the output end of the three-phase eddy current mixing unit; the bubble generating unit is used for conveying a water body with bubbles to the output end of the three-phase eddy current mixing unit.

[0009] In a possible implementation manner, the bubble generating unit includes a gas-liquid mixing device and a gas-liquid separator;

[0010] The input end of the gas-liquid mixing device is used for communicating with a water source and compressed air, and the output end of the gas-liquid mixing device is communicated with the input end of the gas-liquid separator; the gas-liquid mixing device is used for dissolving compressed air in the water source;

[0011] The output end of the gas-liquid separator is communicated with the output end of the three-phase eddy current mixing unit; the gas-liquid separator is used for generating bubbles in the water source from the air dissolved in the water source.

[0012] In a possible implementation manner, the input end of the gas-liquid mixing device is communicated with the output end of the flotation tank, and the flotation tank supplies the water source to the gas-liquid mixing device, and the water source is the purified water body in the flotation tank.

[0013] In a possible implementation manner, the three-phase eddy current mixing unit includes at least one eddy current mixing device for eddy current mixing of sewage and compressed air.

[0014] In a possible implementation manner, the three-phase eddy current mixing unit includes two to five groups of eddy current mixing devices that are connected in series.

[0015] In a possible implementation manner, the eddy current mixing device includes an inner cylinder and an outer cylinder. The inner cylinder is hermetically nested in the outer cylinder. A first chamber is provided between the inner cylinder and the outer cylinder, and a second chamber is provided in the inner cylinder;

[0016] A water inlet pipe is provided on the outer cylinder, and the water inlet pipe communicates with the first chamber;

[0017] One end of the inner cylinder is provided with an air inlet pipe for communicating compressed air, and the other end is provided with a drain port; A diversion hole communicating the first chamber and the second chamber is also provided on the inner cylinder, and in the radial direction of the inner cylinder, the diversion hole is inclined.

[0018] In a possible implementation manner, in the direction perpendicular to the axial direction of the inner cylinder, the diversion hole is inclined; The perpendicular distance between the end of the diversion hole close to the first chamber and the air inlet pipe is less than the perpendicular distance between the end of the diversion hole close to the second chamber and the air inlet pipe.

[0019] In a possible implementation manner, the diversion hole includes a first through hole and a second through hole that are connected in communication. The first through hole is provided close to the first chamber, and the second through hole is provided close to the second chamber; An adjusting member is connected in the second through hole to adjust the opening size of the end of the second through hole close to the second chamber.

[0020] In a possible implementation manner, the flotation device further includes a slag scraping unit provided above the flotation tank; The slag scraping unit is used to scrape off the pollutants floating on the flotation tank.

[0021] In another aspect, the present application also provides a sewage treatment system including the flotation device.

[0022] The beneficial effect of the present application is that the present application proposes a flotation device, including a three-phase eddy current mixing unit, a contact tank, a flotation tank and a bubble generating unit, wherein the three-phase eddy current mixing unit, the contact tank and the flotation tank are connected in sequence; It can be understood that the output end of the three-phase eddy current mixing unit is connected to the contact tank. The output end of the bubble generating unit is connected into the contact tank and communicates with the output end of the three-phase eddy current mixing unit.

[0023] During operation, the three-phase eddy current mixing unit fully mixes sewage and compressed air to form flocculants; the bubble generating unit can deliver a water body with bubbles to the output end of the three-phase eddy current mixing unit. Thus, under the action of the bubbles generated by the bubble generating unit, the flocculants generated in the three-phase eddy current mixing unit can be boosted to rise in the contact tank, that is, the bubbles attached with solid or liquid pollutants are pushed to float, thereby increasing the speed of separating pollutants from the water body, that is, improving the sewage purification efficiency. Brief Description of the Drawings

[0024] To more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0025] Figure 1 Shows a schematic diagram of the principle of a partial structure of a flotation device;

[0026] Figure 2 Shows a schematic diagram of the principle of another partial structure of a flotation device;

[0027] Figure 3 Shows a top view structural schematic diagram of a flotation device;

[0028] Figure 4 Shows a side view structural schematic diagram of a flotation device;

[0029] Figure 5 Shows a longitudinal sectional structural schematic diagram of a vortex mixing device;

[0030] Figure 6 Shows Figure 5 A partial enlarged structural schematic diagram of part A therein;

[0031] Figure 7 Shows a transverse sectional structural schematic diagram of a vortex mixing device;

[0032] Figure 8 Shows another longitudinal sectional structural schematic diagram of a vortex mixing device;

[0033] Figure 9 Shows another transverse sectional structural schematic diagram of a vortex mixing device;

[0034] Figure 10 Shows a partial structural schematic diagram of the adjusting member and the diversion hole in cooperation connection in a state;

[0035] Figure 11Shows a partial structural schematic diagram of the adjusting member and the diversion hole in cooperation and connection in another state.

[0036] Description of main component symbols:

[0037] 1 - Feed water pump;

[0038] 2 - Three - phase eddy current mixing unit; 21 - Eddy current mixing device; 211 - Outer cylinder; 212 - Inner cylinder; 2121 - Diversion hole; 21211 - First through - hole; 21212 - Second through - hole; 213 - First chamber; 214 - Second chamber; 215 - Air inlet pipe; 216 - Drain port; 217 - Water inlet pipe; 218 - Adjusting member; 201 - First eddy current mixing device; 202 - Second eddy current mixing device; 203 - Input end; 204 - Output end;

[0039] 3 - Contact tank;

[0040] 4 - Scum scraping unit; 401 - Scum scraper; 402 - Scum scraping trough; 402a - Slag discharge port;

[0041] 5 - Flotation tank;

[0042] 6 - Drain pipe;

[0043] 7 - Bubble generating unit; 701 - Gas - liquid mixing device; 702 - Gas - liquid separator;

[0044] 8 - Air compression unit;

[0045] 9 - Control unit;

[0046] 10 - Support platform;

[0047] 11 - Ladder;

[0048] 1201 - First partition; 1202 - Second partition. Detailed implementation manners

[0049] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application, and should not be construed as a limitation to the present application.

[0050] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present application.

[0051] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality of" means two or more unless otherwise specifically defined.

[0052] In the present application, unless otherwise clearly defined and limited, the terms "mounted", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and may be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0053] In the present application, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "under" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0054] In the process of sewage purification, physical, chemical and biological methods are usually used to filter, decompose, separate and other operations on the pollutants in the sewage to achieve the purification treatment of the sewage. In the process of sewage purification, the air flotation method is also a commonly used sewage purification treatment method. Among them, the air flotation method is to generate highly dispersed microbubbles in water, and the bubbles carry pollutants such as solids and liquids in the sewage to float to the surface of the water body, so as to achieve the effect of separating pollutants from the water body, that is, to achieve the purification treatment of the sewage.

[0055] In the embodiment, an air flotation device is provided, which can separate solid or liquid pollutants in sewage from the water body under the action of bubbles, so as to realize the purification of sewage. Specifically, pollutants such as suspended solids, oils and fats, animal fats, emulsified oil colloid particles, and other insoluble particles in the water body can float to the surface of the water body to realize the purification treatment of sewage.

[0056] Embodiment 1

[0057] As Figure 1 and Figure 2 shown, in the embodiment, the air flotation device includes a three-phase eddy current mixing unit 2, a contact tank 3, an air flotation tank 5, and a bubble generating unit 7. The three-phase eddy current mixing unit 2 is connected to the sewage water source and the compressed air source; the output end 204 of the three-phase eddy current mixing unit 2 is connected to the contact tank 3; the contact tank 3 is connected to the air flotation tank 5.

[0058] In use, when the sewage is sent into the three-phase eddy current mixing unit 2, the medicament can be first injected into the sewage, that is, the sewage added with the medicament is sent into the three-phase eddy current mixing unit 2; and compressed air is injected into the three-phase eddy current mixing unit 2. The three-phase eddy current mixing unit 2 can fully mix the sewage and the compressed air, and at the same time make the medicament fully mixed in the sewage. The sewage treated by the three-phase eddy current mixing unit 2 generates a flocculant of solid-liquid-gas three-phase mixture, and then the mixed and treated sewage is sent to the contact tank 3. When the flocculant enters the contact tank 3, due to the sudden increase in space, the pressure received by the flocculant will decrease, so that the dissolved gas in the flocculant is slowly released and grows, causing the flocculant to float; the water body carries the flocculant into the air flotation tank 5, and in the air flotation tank 5, the flocculant floats to the surface of the water body. It can be understood that the flocculant can refer to bubbles attached with solid or liquid pollutants, and gradually float to the surface of the water body under the action of the buoyancy of the bubbles, so as to realize the separation of pollutants from the water body, that is, to realize the purification of sewage.

[0059] In the embodiment, the output end of the bubble generating unit 7 is connected to the contact tank 3 and is connected to the output end of the three-phase eddy current mixing unit 2. The bubble generating unit 7 is used to dissolve compressed gas in the water body and generate bubbles. The bubble generating unit 7 can supply the water body carrying bubbles to the output end 204 of the three-phase eddy current mixing unit 2 and release it in the contact tank 3. Under the boosting action of this part of the bubbles, the flocculant can be pushed to quickly rise to the surface of the water body, so as to accelerate the separation rate of pollutants from the water body, that is, to improve the sewage purification rate.

[0060] Embodiment 2

[0061] In the embodiment, an air flotation device is provided. It can be understood that this embodiment is a further improvement based on Embodiment 1.

[0062] AsFigure 1 As shown in the figure, the air flotation device further includes a feed water pump 1. The input end of the feed water pump 1 is used to connect to the sewage water source; the output end of the feed water pump 1 is connected to the input end 203 of the three-phase eddy current mixing unit 2, so that the sewage is sent into the three-phase eddy current mixing unit 2 by the feed water pump 1. And the feed water pump 1 serves as a power source, which can promote the flow of sewage and continuously send the sewage into the three-phase eddy current mixing unit 2. During use, the input end of the feed water pump 1 can be connected to the regulating tank of the sewage treatment system, so as to continuously send the sewage in the regulating tank to the three-phase eddy current mixing unit 2.

[0063] In some specific embodiments, the feed water pump 1 can be selected as a high-pressure water pump, so that the sewage entering the three-phase eddy current mixing unit 2 is a high-pressure water flow. Exemplarily, the feed water pump 1 can be selected as a high-pressure water pump with a lift of 65m.

[0064] As Figure 3 shown in the figure, two feed water pumps 1 can be provided. One of them is in normal use, and the other feed water pump 1 can be used as a standby. When one of the feed water pumps 1 fails, the standby feed water pump 1 can be started to make the air flotation device continue to work to ensure the working efficiency of the air flotation device; subsequently, the operator can repair or replace the faulty feed water pump 1.

[0065] As Figure 1 、 Figure 3 and Figure 4 shown in the figure, the three-phase eddy current mixing unit 2 includes at least one set of eddy current mixing devices 21, and the sewage, chemicals and compressed air are mixed by the eddy current mixing devices 21. When multiple sets of eddy current mixing devices 21 are provided, the multiple sets of eddy current mixing devices 21 are connected in series. It can be understood that the input end of the eddy current mixing device 21 at the head end can be connected to the feed water pump 1 through a pipeline; the output end of the eddy current mixing device 21 at the tail end can be connected to the contact tank 3 through a water pipe.

[0066] In some embodiments, the three-phase eddy current mixing unit 2 can be provided with two to five sets of eddy current mixing devices 21.

[0067] In some specific embodiments, the three-phase eddy current mixing unit 2 may include two groups, three groups, five groups or other numbers of eddy current mixing devices 21. Specifically, the number of eddy current mixing devices 21 can be set according to the needs of the sewage quality. Exemplarily, when the content of pollutants in the sewage is low, a flocculant and polyacrylamide can be added to the sewage respectively; correspondingly, two groups of eddy current mixing devices 21 can be set. Among them, the flocculant can be mixed with the sewage and compressed air in the first group of eddy current mixing devices 21; polyacrylamide can be added to the sewage in the second group of eddy current mixing devices 21 and mixed with the sewage and compressed air. When the content of pollutants in the sewage is high, for example, when the content of suspended solids and oil reaches 2000 mg / L, more kinds of medicaments need to be added to the sewage to fully purify the water body; exemplarily, a flocculant, polyacrylamide, demulsifier and pH adjuster can be added to the sewage respectively, and four groups of eddy current mixing devices 21 can be set correspondingly, so that the four medicaments are added to the sewage through one group of eddy current mixing devices 21 respectively and fully mixed.

[0068] Exemplarily, such as Figure 1 As shown, in this embodiment, the three-phase eddy current mixing unit 2 includes two groups of eddy current mixing devices 21, namely the first eddy current mixing device 201 and the second eddy current mixing device 202. The output end of the first eddy current mixing device 201 is connected to the output end of the feed water pump 1 through a pipeline. The output end of the first eddy current mixing device 201 is connected to the input end of the second eddy current mixing device 202 through a pipeline. The output end of the second eddy current mixing device 202 is connected to the contact tank 3 through a pipeline; one end of the pipeline far from the second eddy current mixing device 202 can be used as the output end 204 of the three-phase eddy current mixing unit 2.

[0069] In the embodiment, the structures of multiple groups of eddy current mixing devices 21 are the same, and the eddy current mixing device 21 at the head end is taken as an example for introduction.

[0070] Such as Figures 5 to 9 As shown, the eddy current mixing device 21 includes an outer cylinder 211 and an inner cylinder 212. The inner cylinder 212 is hermetically nested in the outer cylinder 211. At the same time, a first chamber 213 is formed between the outer cylinder 211 and the inner cylinder 212; a second chamber 214 is provided inside the inner cylinder 212.

[0071] In some specific embodiments, both the outer cylinder 211 and the inner cylinder 212 are cylindrical. A water inlet pipe 217 is provided on one side of the outer cylinder 211, and the water inlet pipe 217 is communicated with the first chamber 213. One end of the water inlet pipe 217 far from the first chamber 213 is used to communicate with the feed water pump 1, so as to introduce the sewage into the first chamber 213, that is, to introduce the sewage into the eddy current mixing device 21.

[0072] In the axial direction of the inner cylinder 212, an air inlet pipe 215 is provided at one end of the inner cylinder 212. The air inlet pipe 215 is communicated with the second chamber 214. The air inlet pipe 215 is used to communicate with the air source of compressed air to inject compressed air into the second chamber 214, that is, to inject compressed air into the eddy current mixing device 21. At the end of the inner cylinder 212 away from the air inlet pipe 215, a drain port 216 is provided. The drain port 216 can be used as the output end of the eddy current mixing device 21 to discharge the three-phase mixed sewage from the eddy current mixing device 21. It can be understood that during normal use, the air inlet pipe 215 is provided at the top of the inner cylinder 212, and the drain port 216 is provided at the bottom of the inner cylinder 212.

[0073] A plurality of diversion holes 2121 communicating the first chamber 213 and the second chamber 214 are provided on the inner cylinder 212, so that the sewage located in the first chamber 213 enters the second chamber 214 and then is discharged from the drain port 216.

[0074] As Figures 5 to 7 shown, specifically, in the radial direction of the inner cylinder 212, the diversion holes 2121 are provided in multiple layers, and the multiple layers of diversion holes 2121 can be evenly spaced. A plurality of diversion holes 2121 are circumferentially arranged around the inner cylinder 212, that is, a plurality of diversion holes 2121 are provided in the same layer. Among them, the number of diversion holes 2121 in the same layer can be set to three, five, six, seven, eight, etc. according to needs, and no specific limitation is made here.

[0075] In the radial direction of the inner cylinder 212, the diversion holes 2121 are inclined, that is, the extending direction of the diversion holes 2121 intersects with the corresponding radial direction of the inner cylinder 212; and the plurality of diversion holes 2121 in the same layer are all inclined in the same direction. When introducing the sewage from the first chamber 213 into the second chamber 214, at the same time, due to the action of the water inlet pump 1, the sewage has a relatively high pressure. Therefore, when the sewage enters the second chamber 214 through the diversion holes 2121, a shear force can be generated, causing the sewage to form an eddy current in the second chamber 214, so that the sewage, the chemical agent and the air are mixed by eddy current to generate a flocculant of solid-liquid-gas three-phase mixture.

[0076] In some specific embodiments, the included angle α between the diversion hole 2121 and the radial direction can be set to 45° to 60°. Exemplarily, the included angle α between the diversion hole 2121 and the radial direction can be set to 45°, 48°, 50°, 55°, 58°, 60°, etc. The included angle α between the diversion hole 2121 and the radial direction can refer to a point on the opening of the diversion hole 2121 near the first chamber 213, and the included angle between the radius of the inner cylinder 212 where the point is located and the section plane of the diversion hole 2121 where the point is located.

[0077] In some specific embodiments, the aperture diameter n of the diversion holes 2121 may be set to 6 mm to 8 mm; for example, the aperture diameter n of the diversion holes 2121 may be set to sizes such as 6 mm, 6.5 mm, 8 mm, etc. Specifically, the aperture diameter n of the diversion holes 2121 can be selected according to the water quality of the sewage. When the water quality is poor, the aperture diameter n of the diversion holes 2121 can be set relatively larger to avoid clogging problems.

[0078] In some specific embodiments, in a direction perpendicular to the axial direction of the inner cylinder 212, the diversion holes 2121 are inclined; it can be understood that the diversion holes 2121 have a span in the height direction of the inner cylinder 212. Among them, one end of the diversion hole 2121 close to the second chamber 214 is arranged close to the drain port 216, and the other end of the diversion hole 2121 is arranged close to the air inlet pipe 215. Thus, when the sewage enters the second chamber 214 through the diversion holes 2121, a downward spiral vortex can be formed, which plays a guiding role in the flow direction of the sewage, that is, guiding the sewage in the direction of the drain port 216. Relative to the horizontal direction, the inclination angle γ of the diversion holes 2121 can be set to 5° to 10°; for example, the inclination angle γ of the diversion holes 2121 can be set to angles such as 5°, 8°, 8.5°, 10°, etc. Specifically, the inclination angle γ of the diversion holes 2121 can be determined according to the head and flow rate of the water inlet pump 1; the greater the head and flow rate of the water inlet pump 1, the smaller the inclination angle γ of the diversion holes 2121 can be set; the smaller the head and flow rate of the water inlet pump 1, the relatively larger the inclination angle of the diversion holes 2121 can be set.

[0079] As Figure 8 shown, in some other embodiments, the diversion holes 2121 can also be arranged parallel to the horizontal direction.

[0080] As Figure 9 shown, in some other embodiments, in the axial extension direction of the diversion holes 2121, the diversion holes 2121 may include a first through hole 21211 and a second through hole 21212 that are connected; among them, the first through hole 21211 is arranged close to the first chamber 213, and the second through hole 21212 is arranged close to the second chamber 214. Of course, in some other embodiments, the diversion holes 2121 can also be set in other shapes, as long as they are inclined relative to the radial direction.

[0081] As Figure 10 and Figure 11As shown, in some other embodiments, an adjusting member 218 is connected inside the diversion hole 2121. The adjusting member 218 is in threaded fit connection with the second through hole 21212, and a gap for sewage to pass through is formed between the threaded connections. One end of the adjusting member 218 close to the second chamber 214 is conical. Thus, by screwing in / screwing out the adjusting member 218, the size of the opening at one end of the second through hole 21212 close to the second chamber 214 can be adjusted, and then the pressure of the sewage flow passing through can be adjusted, that is, the water pressure of the sewage entering the second chamber 214 is adjusted, so that the size of the bubbles in the generated flocs can be adjusted.

[0082] In some embodiments, a chemical adding pipe (not shown in the figure) is further provided at one end of the water inlet pipe 217 for connecting to the water inlet pump 1. The chemical adding pipe is communicated with the water inlet pipe 217. Thus, chemicals can be added to the sewage passing through the water inlet pipe 217 through the chemical adding pipe.

[0083] In use, the sewage is sent into the eddy current mixing device 21 after passing through the water inlet pump 1; during this period, chemicals can be added to the sewage through the chemical adding pipe. The sewage enters the first chamber 213 through the water inlet pipe 217; subsequently, it enters the second chamber 214 from the first chamber 213 through the diversion hole 2121. At the same time, compressed air is delivered into the second chamber 214 through the air inlet pipe 215. Under the high pressure of the sewage and the action of the diversion hole 2121, the sewage forms an eddy current in the second chamber 214, so that the chemicals, sewage and compressed air are fully mixed to form a floc of solid-liquid-gas three-phase mixture. The floc then discharges from the drainage port 216 with the water body from the eddy current mixing device 21. Among them, the size of the bubbles in the floc can reach 20μm - 60μm, which is smaller than the bubbles generated by traditional air flotation equipment. Thus, in the air flotation equipment provided by the present application, the floc can float up faster; at the same time, the number of generated bubbles will also be more, carrying more pollutants to float up, improving the sewage purification effect.

[0084] When multiple chemicals need to be added to the sewage according to the water quality of the sewage, the sewage can pass through the corresponding number of eddy current mixing devices 21 in sequence, so that the chemicals are mixed into the sewage one by one. Subsequently, the water body after eddy current mixing is discharged from the output end 204 of the three-phase eddy current mixing unit 2 into the contact tank 3 and gradually flows into the air flotation tank 5.

[0085] As Figures 1 to 4 shown, the contact tank 3 and the air flotation tank 5 can be located in the same box body; the corresponding box body can be divided into two chambers, namely the contact tank 3 and the air flotation tank 5, by the first partition plate 1201. The first partition plate 1201 extends upward from the bottom of the box body, so that the upper ends of the contact tank 3 and the air flotation tank 5 are communicated, that is, the sewage overflows from the contact tank 3 into the air flotation tank 5.

[0086] The three-phase eddy current mixing unit 2 can be arranged on one side of the contact tank 3; it can be understood that the three-phase eddy current mixing unit 2 is arranged outside the box body. The output end 204 of the three-phase eddy current mixing unit 2 extends into the bottom of the contact tank 3 through a pipeline. Thus, after the sewage enters the contact tank 3 through the output end 204, it can enter the flotation tank 5 after a floating-up journey, so as to provide sufficient floating-up time for the flocs in the sewage.

[0087] Since the contact tank 3 and the flotation tank 5 have a relatively large space relative to the three-phase eddy current mixing unit 2, when the sewage enters the contact tank 3 through the output end 204 and gradually flows into the flotation tank 5, the pressure of the sewage decreases, so that the dissolved gas in the flocs is gradually released and grows. At the same time, the water in the flocs is gradually thrown out. While the water content of the flocs decreases significantly, its own specific gravity becomes lighter and lighter, and it can float to the surface of the water body without external force in a few seconds.

[0088] During use, the sewage carrying flocs enters the contact tank 3 through the output end 204 of the three-phase eddy current mixing unit 2, and the dissolved gas in the flocs begins to be gradually released and grow, causing the flocs to gradually float upward in the water body. At the same time, the sewage gradually overflows from the contact tank 3 into the flotation tank 5, and the flocs can complete floating in the flotation tank 5, so that the pollutants float on the surface of the water body, separating the pollutants from the water body.

[0089] Traditional flotation equipment generates bubbles directly in the flotation tank, and then makes the pollutants attach to the bubbles and float. As the use time prolongs, the bubble generation port is prone to be blocked by pollutants, thus affecting the sewage purification effect.

[0090] In this application, a three-phase eddy current mixing unit 2 is used to generate flocs of solid-liquid-gas three-phase mixture, that is, pollutants are attached to bubbles to form flocs in the three-phase eddy current mixing unit 2. After the sewage enters the contact tank 3, the dissolved gas in the flocs is released and grows, driving the pollutants to float, thus avoiding the accumulation of pollutants at the output end 204, and further avoiding the problem of blockage of the output end 204, realizing long-term stable operation; at the same time, the problem of bubble churning can also be avoided, ensuring the purification quality. The floating flocs are firm and have a low water content, achieving a removal effect that cannot be achieved by traditional air flotation equipment on the premise of reducing sludge production, ensuring the purification quality. Since the three-phase eddy current mixing unit 2 can achieve efficient mixing, it can, to a certain extent, improve the efficiency of removing total suspended particles, oils and animal fats, other insoluble particles, oil droplets in an emulsified state, colloidal particles, etc. in water, and at the same time reduce the biochemical oxygen demand (BOD) and chemical oxygen demand (COD) of sewage caused by the above pollutants. At the same time, compared with traditional air flotation equipment, components such as a pressure pump, a large container tank, and a release head can be omitted, reducing power consumption and achieving the effect of energy conservation and emission reduction; at the same time, the noise during the operation of the air flotation equipment can also be reduced accordingly.

[0091] In the embodiment, a second partition 1202 is further provided in the box body. The second partition 1202 is arranged in the air flotation tank 5 and extends downward from the top of the box body, so that the spaces on both sides of the second partition 1202 communicate at a position close to the bottom of the box body. It can be understood that the second partition 1202 is arranged away from the contact tank 3. The water body after air flotation treatment can flow into the space on the side of the second partition 1202 away from the contact tank 3 through the communication position below the second partition 1202. Correspondingly, a drain pipe 6 is connected to the top of the space on the side of the second partition 1202 away from the contact tank 3, so that the water body after air flotation treatment can be discharged outward for subsequent treatment or use.

[0092] As Figures 1 to 4 shown, a slag scraping unit 4 is further provided at the top of the air flotation tank 5 for cleaning the pollutants floating on the water surface in the air flotation tank 5 out of the air flotation tank 5. Specifically, the slag scraping unit 4 includes a slag scraper 401 and a slag scraping trough 402. The slag scraper 401 is installed at the top of the air flotation tank 5; the slag scraping trough 402 is arranged close to the upper end of the air flotation tank 5, and the opening end of the slag scraping trough 402 is arranged higher than the water surface. The slag scraper 401 is used to scrape the pollutants floating in the air flotation tank 5 into the slag scraping trough 402. A slag discharge port 402a is arranged at the bottom of the slag scraping trough 402, and the slag discharge port 402a can be connected to a device for treating sludge outside. During use, the pollutants entering the slag scraping trough 402 can flow out by themselves and enter the sludge treatment device for subsequent treatment.

[0093] As Figures 2 to 4As shown in the figure, further, the bubble generation unit 7 is connected to the contact tank 3 and communicates with the output end of the three-phase eddy current mixing unit 2. The bubble generation unit 7 is used to dissolve bubbles in the water flow, and then supply the water body with dissolved bubbles to the output end of the three-phase eddy current mixing unit 2, so as to boost the flocs in the sewage to float, thereby increasing the floating speed of the flocs, that is, increasing the separation speed of pollutants from the water body, and further improving the treatment rate of the air flotation device.

[0094] Specifically, the bubble generation unit 7 includes a gas-liquid mixing device 701 and a gas-liquid separator 702. Among them, the input end of the gas-liquid mixing device 701 is connected to the water body chamber in the air flotation tank 5 through a pipeline, that is, the space on the side of the second partition 1202 away from the contact tank 3. Thus, the air flotation tank 5 directly supplies water source to the gas-liquid mixing device 701. The input end of the gas-liquid mixing device 701 is also connected to a compressed air source to supply compressed air to the gas-liquid mixing device 701.

[0095] In some other embodiments, the input end of the gas-liquid mixing device 701 can also be connected to an external water source.

[0096] In some specific embodiments, the gas-liquid mixing device 701 can be a gas-liquid mixing pump with a lift of 58m, so as to pump the treated water body from the air flotation tank 5. The gas-liquid mixing pump includes an impeller (not shown in the figure), a pump body and a pump cover (not shown in the figure); when the impeller rotates, under the action of centrifugal force, the circumferential speed of the liquid in the impeller is greater than the circumferential speed of the liquid in the flow channel, thus forming a circular flow of the liquid. At the same time, since the liquid follows the impeller and flows from the input end to the output end of the gas-liquid mixing pump, under the combined action of these two movement modes, a longitudinal vortex in the same direction as the impeller rotation is generated in the liquid. The liquid flows repeatedly in the flow channel of the gas-liquid mixing pump and between the blades, and is pressurized by multiple eddy currents, while being fully stirred and mixed in contact, so that the air insoluble in water can be mixed into the water body, that is, the mixing of compressed air and water body is realized.

[0097] In some other embodiments, the gas-liquid mixing device 701 can also be the eddy current mixing device 21 provided in this application in cooperation with the water inlet pump 1 to realize dissolving compressed air in the water body.

[0098] Further, the output end of the gas-liquid mixing device 701 is connected to the input end of the gas-liquid separator 702; the output end of the gas-liquid separator 702 is connected to the output end 204 of the three-phase eddy current mixing unit 2. The gas-liquid separator 702 is used to separate the air dissolved in the water body to form bubbles in the water body.

[0099] In use, the gas-liquid mixing device 701 fully mixes the water source and compressed air, first dissolving the air in the water body. Then, the gas-liquid separator 702 separates the air from the water body, forming air bubbles in the water body. Subsequently, the water body carrying the bubbles is supplied to the output end 204 of the three-phase vortex mixing unit 2; the bubbles in this part boost the flocculants to float in the water body, thereby increasing the floating rate of the flocculants, that is, increasing the floating rate of pollutants, and further improving the efficiency of sewage air flotation treatment.

[0100] Further, in the embodiment, the air flotation device further includes an air compression unit 8. The input end of the gas-liquid mixing device 701 is communicated with the air compression unit 8, and the air compression unit 8 supplies compressed air to the gas-liquid mixing device 701. In some specific embodiments, the air compression unit 8 may include equipment such as an air compressor for compressing air.

[0101] In some embodiments, the intake pipe 215 of the three-phase vortex mixing unit 2 may also be directly connected to the air compression unit 8, and the air compression unit 8 supplies compressed air to the three-phase vortex mixing unit 2.

[0102] As Figure 3 and Figure 4 shown, the air flotation device further includes a control unit 9. The water inlet pump 1, the slag scraping unit 4, and the bubble generating unit 7 are all electrically connected to the control unit 9, so that the control unit 9 coordinates the work of each part to realize the automatic control of air flotation treatment.

[0103] A support platform 10 is also provided at the top of the air flotation tank 5; correspondingly, a ladder 11 is provided on one side of the air flotation tank 5. This facilitates the operator to climb to the top of the air flotation tank 5 to check the situation inside the air flotation tank 5; at the same time, it also facilitates the operator to repair the equipment located at the top of the air flotation tank 5.

[0104] In the embodiment, the provided air flotation device can quickly float the flocculants in the water body to the water surface, thereby improving the sewage purification efficiency.

[0105] Embodiment Three

[0106] The embodiment also provides a sewage treatment system, including the air flotation device provided in Embodiment One or Embodiment Two.

[0107] Of course, the sewage treatment system may also include a grille area, a sedimentation tank, an adjustment tank, a microbial purification tank, and a filtration adsorption tank. The grille area, the sedimentation tank, the adjustment tank, the air flotation device, the microbial purification tank, and the adsorption filtration tank are connected in sequence. Thus, the sewage can be purified step by step to filter out the soluble, insoluble pollutants and microorganisms in the sewage, etc., so that the water body is purified.

[0108] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0109] Although the embodiments of this application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting this application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. An air flotation device, characterized in that, It includes a three-phase eddy current mixing unit, a contact tank, a flotation tank, and a bubble generation unit. The three-phase eddy current mixing unit, the contact tank, and the flotation tank are connected in sequence; The three-phase eddy current mixing unit is connected to a sewage water source and a compressed air source. The three-phase eddy current mixing unit is used for performing three-phase eddy current mixing on sewage to generate flocs. The three-phase eddy current mixing unit includes at least one eddy current mixing device. The eddy current mixing device includes an inner cylinder and an outer cylinder. The inner cylinder is hermetically nested in the outer cylinder. A first chamber is provided between the inner cylinder and the outer cylinder. A second chamber is provided in the inner cylinder. An inlet pipe is provided on the outer cylinder, and the inlet pipe is communicated with the first chamber. One end of the inner cylinder is provided with an inlet pipe for communicating compressed air, and the other end is provided with a drain port. A diversion hole for communicating the first chamber and the second chamber is further provided on the inner cylinder. In the radial direction of the inner cylinder, the diversion hole is inclined. The vertical distance between the end of the diversion hole close to the first chamber and the inlet pipe is less than the vertical distance between the end of the diversion hole close to the second chamber and the inlet pipe. The diversion hole includes a first through hole and a second through hole which are connected in communication. The first through hole is close to the first chamber, and the second through hole is close to the second chamber. An adjusting member is connected in the second through hole to adjust the opening size of the end of the second through hole close to the second chamber. The end of the adjusting member close to the second chamber is conical; The output end of the bubble generation unit is communicated to the contact tank and is communicated with the output end of the three-phase eddy current mixing unit. The bubble generation unit is used for conveying a water body with bubbles to the output end of the three-phase eddy current mixing unit.

2. The air flotation device according to claim 1, wherein, The bubble generation unit includes a gas-liquid mixing device and a gas-liquid separator; The input end of the gas-liquid mixing device is used for communicating with a water source and compressed air. The output end of the gas-liquid mixing device is communicated with the input end of the gas-liquid separator. The gas-liquid mixing device is used for dissolving compressed air in the water source; The output end of the gas-liquid separator is communicated with the output end of the three-phase eddy current mixing unit. The gas-liquid separator is used for generating bubbles in the water source by the air dissolved in the water source.

3. The air flotation device according to claim 2, wherein The input end of the gas-liquid mixing device is communicated with the output end of the flotation tank. The flotation tank supplies a water source to the gas-liquid mixing device. The water source is the purified water body in the flotation tank.

4. The air flotation device according to claim 1, wherein, The three-phase eddy current mixing unit includes two to five groups of eddy current mixing devices, and the two to five groups of eddy current mixing devices are connected in series.

5. The air flotation device according to claim 1, wherein The flotation equipment further includes a slag scraping unit. The slag scraping unit is arranged above the flotation tank. The slag scraping unit is used for scraping the pollutants floating on the flotation tank.

6. A sewage treatment system, characterized in that, It includes the flotation equipment according to any one of claims 1 to 5.

Images