Air floatation equipment and control method

Abstract

The invention discloses air flotation equipment and a control method, and belongs to the technical field of produced water treatment equipment.The air flotation equipment comprises a tank body and a drainage structure, the tank body is provided with a carrier gas inlet, a liquid inlet, a water phase outlet and an organic phase overflow port, the drainage structure is provided with a guide channel, and the upper side and the lower side of the guide channel are each of an open structure; one end of the guide channel is adjacent to the liquid inlet, the other end of the guide channel extends towards the central area of the tank body along the spiral path so as to guide liquid entering the containing cavity to form a swirling flow field, an organic phase in the liquid floats upwards and is separated under the action of the swirling flow field and is discharged through the organic phase overflow port, and part of the organic phase is attached to the inner wall of the guide channel; and the separated water phase is discharged through a water phase outlet. The invention provides air floatation equipment and a control method, and aims to solve the technical problems of low equipment separation efficiency, large equipment size and limited treatment capacity caused by insufficient coalescence capacity on fine oil drops due to the fact that existing air floatation equipment realizes oil-water separation by depending on bubble floating.

Description

Technical Field

[0001] This application belongs to the technical field of produced water treatment equipment, specifically relating to an air flotation device and its control method. Background Technology

[0002] Produced water typically contains a large number of dispersed oil droplets and bubbles, requiring deoiling treatment to meet discharge or reinjection requirements. In traditional air flotation (AF) equipment, circulating water and carrier gas are mixed and dispersed in an ejector or mixer to form an air-water mixture. This mixture is then mixed with the produced water and enters the AF chamber. Once inside the AF chamber, the rising bubbles adsorb and bind with the dispersed fine oil droplets, significantly increasing the buoyancy of the oil droplets, thereby promoting oil phase flotation and achieving oil-water separation.

[0003] However, existing air flotation devices focus on the coupling mechanism between bubbles and oil droplets, which limits separation efficiency when treating produced water containing a high proportion of fine oil droplets or with high viscosity and strong emulsification. The equipment requires a large volume to ensure sufficient guidance time and bubble contact opportunities, thus limiting the device's processing capacity and making it difficult to meet the needs of high-flux produced water scenarios. Furthermore, the low coalescence rate of fine oil droplets easily leads to fluctuations in effluent oil concentration and unstable treatment. Long-term operation may also cause maintenance problems such as floc clogging, further increasing operating and maintenance costs. Summary of the Invention

[0004] This application provides an air flotation device and control method to solve the technical problems of existing air flotation devices relying on the rise of air bubbles to achieve oil-water separation, resulting in insufficient ability to coalesce fine oil droplets, thus causing low separation efficiency, large device size and limited processing capacity.

[0005] The primary objective of this application is to provide an air flotation device, the technical solution of which is as follows: An air flotation device includes a tank and a flow guiding structure. The tank has a receiving cavity, and the flow guiding structure is disposed in the receiving cavity. The tank has a carrier gas inlet, a liquid inlet, a water phase outlet, and an organic phase overflow outlet. The carrier gas inlet is located at the top of the tank, the water phase outlet is located below the flow guiding structure, and the organic phase overflow outlet is located above the flow guiding structure. The flow guiding structure has a guiding channel, the upper and lower sides of which are open structures. One end of the guiding channel is adjacent to the liquid inlet, and the other end extends along a spiral path toward the central area of ​​the tank to guide the liquid entering the receiving cavity to form a swirling flow field. Under the action of the swirling flow field, the organic phase in the liquid floats and separates and is discharged through the organic phase overflow outlet. Some of the organic phase adheres to the inner wall of the guiding channel, and the separated water phase is discharged through the water phase outlet.

[0006] The air flotation device according to the first objective of this application also includes the following additional technical features: The flow-guiding structure is spirally arranged to form a guiding channel. The inlet is located on the side wall of the tank. The starting end of the guiding channel is located on the outlet path of the inlet. The flow-guiding structure has a connecting end that connects to the inner wall of the tank. The outer side of the flow-guiding structure at the connecting end is tangential to the inner wall of the tank so that the liquid entering the receiving cavity flows spirally along the flow-guiding structure.

[0007] The flotation equipment also includes a cleaning device. The flow-guiding structure extends along the axial direction of the tank. The cleaning device includes a cleaning scraper, which is disposed on the inner wall of the guide channel near the center of the swirl. The cleaning scraper is movable relative to the flow-guiding structure to clean the organic phase adhering to the guide channel.

[0008] The cleaning device also includes a drive unit, a cleaning scraper is arranged along the axial direction of the guide channel, the output shaft of the drive unit is connected to the cleaning scraper, and the drive unit drives the cleaning scraper to move along the axial direction of the tank.

[0009] The cleaning device also includes a mounting component located at the bottom of the cleaning scraper, the cleaning scraper being fixed to the mounting component, and the cleaning scraper having a fitting wall that conforms to the inner wall of the guide channel.

[0010] The cleaning scraper includes a fixed wall connected to the mounting component and a guide wall connecting the fixed wall and the fitting wall. The mounting component has a storage cavity and a guide port communicating with the storage cavity. The guide wall is inclined to guide the organic phase attached to the guide channel to the guide port.

[0011] The organic phase overflow port is located at the top of the tank, and the aqueous phase outlet is located at the bottom of the tank. An overflow baffle is provided above the drainage structure. One end of the overflow baffle is fixedly connected to the inner wall of the receiving cavity, and the other end extends upward in an arc towards the axis of the tank. The connection end between the overflow baffle and the inner wall of the receiving cavity is located below the organic phase overflow port.

[0012] An auxiliary separation mechanism is provided below the diversion structure. The auxiliary separation mechanism includes a vibrator and a separation net. The separation net is located between the water phase outlet and the diversion structure. The vibrator drives the separation net to vibrate so that the organic phase attached to the separation net aggregates and floats to the surface.

[0013] The liquid inlet includes at least a first liquid inlet and a second liquid inlet, with the first liquid inlet located at a height corresponding to the top of the drainage structure and the second liquid inlet located at a height corresponding to the middle of the drainage structure.

[0014] The second objective of this application is to provide a control method applied to the air flotation device for the first objective, the control method comprising: Obtain the concentration of the organic phase of the liquid to be treated entering the air flotation device; The target guiding time of the drainage structure is determined based on the organic phase concentration. The required vortex intensity to be formed by the drainage structure is determined based on the target guidance time, and the parameters of the drainage structure are matched according to the vortex intensity. The target liquid flow rate entering the flotation device is determined based on the diversion structure and the target guidance time.

[0015] Due to the adoption of the above technical solution, the beneficial effects achieved by this application are as follows: 1. This application incorporates a flow-guiding structure within the container cavity of the tank, with one end of the guiding channel adjacent to the inlet and the other end extending along a spiral path towards the center of the tank. When liquid enters the container cavity from the inlet, it flows along the spiral path under the guidance of the guiding channel, thus forming a swirling flow field within the container cavity. Under the influence of this swirling flow field, different phases in the liquid exhibit a radial separation tendency due to density differences, causing the less dense organic phase to gradually move towards the center of the swirling flow and float upwards. Simultaneously, during this movement towards the center, it coalesces through mutual collisions, thereby improving the aggregation efficiency of the organic phase. Furthermore, since the upper and lower sides of the guiding channel are open structures, the liquid can interact with air bubbles within the container cavity from the vertical direction of the guiding channel during the swirling flow. Sufficient contact allows bubbles to adhere to the organic phase and increase its buoyancy, further promoting the separation of the organic phase. In addition, some organic phase can adhere to the inner wall of the guide channel during the swirling flow, and gradually gather to form larger organic phase droplets or liquid films. Under the action of fluid shear force and buoyancy, these droplets detach from the inner wall and move upward, thus further agglomerating the organic phase that was originally dispersed in the liquid and accelerating its rise. Because the synergistic effect of swirling flow and flotation can accelerate the agglomeration and separation process of the organic phase, the guiding time required for effective separation of the liquid in the equipment is shortened. This allows the equipment to adopt a more compact structural design while meeting the same processing capacity, which is beneficial to reducing the overall size of the equipment and the space occupied by the equipment.

[0016] 2. In a preferred embodiment of this application, by setting the flow guide structure in a spiral shape to form a guide channel, and placing the starting end of the guide channel on the liquid outlet path of the inlet, when the liquid enters the receiving cavity through the inlet located on the side wall of the tank, the liquid can directly enter the guide channel and flow along the spiral path of the flow guide structure, thereby being guided to form a swirling flow in the initial stage of entering the receiving cavity; furthermore, since the flow guide structure has a connection end connected to the inner wall of the tank, and the outer side of the flow guide structure at the connection end is tangential to the inner wall of the tank, the liquid can flow along the tangential direction of the inner wall of the tank after entering the receiving cavity, thereby making it easier to form a stable swirling flow field and avoiding the liquid directly impacting the inside of the tank and causing turbulent flow; during this swirling flow process, it is beneficial to improve the rotational stability of the liquid in the receiving cavity, thereby enhancing the swirling separation effect and promoting the stratification separation of different phases in the liquid, and improving the separation efficiency of the organic phase.

[0017] 3. As a preferred embodiment of this application, since the diversion structure extends axially along the tank body, the guiding channel has a large extension length in the axial direction, thereby increasing the guiding area for the liquid entering the receiving cavity. This allows more liquid to flow along the guiding channel after entering the receiving cavity, which is beneficial for forming a stable swirling flow field. During the process of liquid forming swirling flow, some organic phase can adhere to the inner wall of the guiding channel near the swirling center. By setting a cleaning device and placing a cleaning scraper on the inner wall of the guiding channel near the swirling center, and the cleaning scraper being movable relative to the diversion structure, the organic phase adhering to the inner wall of the guiding channel can be scraped off during the movement, reducing the adhesion residue of organic phase on the inner wall. This allows for cleaning of the inner wall during equipment operation, which is beneficial for shortening the cleaning and maintenance time interval between equipment processing cycles.

[0018] 4. In a preferred embodiment of this application, a driving component is provided, the output shaft of which is connected to the cleaning scraper. Under the driving action of the driving component, the cleaning scraper can be moved along the axial direction of the tank, thereby enabling the cleaning scraper to scrape and clean the inner wall of the guide channel along the axial direction of the drainage structure, so that the organic phase adhering to different positions on the inner wall can be effectively cleaned, thereby improving the cleaning range and cleaning effect of the cleaning scraper on the inner wall of the guide channel.

[0019] Furthermore, by setting a mounting bracket at the bottom of the cleaning scraper and fixing the cleaning scraper to the mounting bracket, the cleaning scraper can be stably installed on the cleaning device, which helps to ensure the structural stability of the cleaning scraper during movement. At the same time, the cleaning scraper has a contact wall that fits with the drainage structure, so that the cleaning scraper can maintain contact with the inner wall of the guide channel during movement, thereby more thoroughly scraping off the organic phase attached to the inner wall of the guide channel and improving the cleaning effect.

[0020] 5. As a preferred embodiment of this application, by providing a fixed wall connected to the mounting component on the cleaning scraper, and providing a guide wall between the fixed wall and the fitting wall, the organic phase adhering to the inner wall of the guide channel can be detached from the inner wall under the scraping action of the fitting wall when the cleaning scraper scrapes the inner wall, and move in an inclined direction under the guidance of the guide wall; at the same time, by providing a storage cavity in the mounting component and providing a guide port communicating with the storage cavity, the organic phase moving under the guidance of the guide wall can enter the storage cavity for temporary collection, thereby facilitating the centralized introduction and storage of the scraped organic phase and preventing the organic phase from re-adhering to the inner wall of the guide channel during the cleaning process.

[0021] 6. In a preferred embodiment of this application, by placing the organic phase overflow port at the upper part of the tank and the aqueous phase outlet at the bottom of the tank, the organic phase floating under the swirling action can gather at the upper part of the tank and be discharged through the organic phase overflow port, while the denser aqueous phase moves to the lower part of the tank and is discharged through the aqueous phase outlet, thereby facilitating the stratified discharge of the organic and aqueous phases. Simultaneously, an overflow baffle is provided above the drainage structure, with one end fixedly connected to the inner wall of the receiving cavity, and the other end extending upwards in an arc shape towards the tank axis. This allows the organic phase floating to the area above the drainage structure to gather under the guidance of the arc-shaped overflow baffle. Furthermore, the connection end between the overflow baffle and the inner wall of the receiving cavity is located below the organic phase overflow port, allowing the floating organic phase to be guided by the overflow baffle during flow and move towards the organic phase overflow port, thereby promoting the discharge of the organic phase through the organic phase overflow port.

[0022] 7. As a preferred embodiment of this application, by setting an auxiliary separation mechanism below the diversion structure and placing the separation net between the water phase outlet and the diversion structure, the liquid flowing from below the diversion structure to the water phase outlet area can pass through the separation net, thereby allowing the organic phase in the liquid to adhere to the separation net when passing through it. At the same time, by setting a vibrator and driving the separation net to vibrate, the organic phase attached to the separation net collides and gradually aggregates into larger organic phase droplets under the vibration. The aggregated organic phase moves upward under the action of buoyancy and re-enters the separation area above, which is conducive to promoting further aggregation and floating separation of the organic phase and improving the oil-water separation effect of the air flotation equipment.

[0023] 8. In a preferred embodiment of this application, the liquid enters the drainage structure through a first inlet located at the top or a second inlet located in the middle. Users can select inlets of different heights according to separation requirements, so that the liquid forms a corresponding initial liquid level in the drainage structure and flows along the spirally extended guide channel to form a swirling flow field. By selecting the position of the inlet, not only can the radial distribution and component force of the liquid in the swirling flow be controlled, but the swirling flow intensity can also be changed to make the swirling flow state more uniform or more intense, so as to adapt to different liquid properties and separation requirements.

[0024] 9. This application obtains the organic phase concentration of the liquid to be treated entering the air flotation equipment and determines the corresponding target guidance time based on the organic phase concentration, enabling the air flotation equipment to select appropriate separation time conditions for liquids with different organic phase concentrations. Furthermore, it determines the required swirling intensity of the guiding structure based on the target guidance time and matches the parameters of the guiding structure according to the swirling intensity, so that the liquid forms a swirling flow state adapted to the target guidance time within the guiding channel of the guiding structure, thereby enhancing the radial migration and upward separation process of the organic phase in the swirling field. Simultaneously, it determines the target liquid flow rate entering the air flotation equipment based on the guiding structure and the target guidance time, matching the actual guidance time of the liquid in the guiding channel with the target guidance time. This ensures separation efficiency while achieving coordinated matching of equipment operating parameters and structural parameters, improving the separation stability and processing efficiency of the air flotation equipment under different organic phase concentration conditions. Attached Figure Description

[0025] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the tank body according to a preferred embodiment of this application; Figure 2 This is a schematic diagram of the installation of the drainage structure, overflow baffle, and auxiliary separation mechanism in the receiving cavity according to a preferred embodiment of this application; Figure 3 This is a schematic diagram of the installation of the drainage structure and the liquid inlet according to a preferred embodiment of this application; Figure 4 This is a schematic diagram of the structure of a cleaning scraper according to a preferred embodiment of this application; Figure 5 This is a flowchart illustrating a preferred embodiment of the control method of this application.

[0026] List of components and reference numerals: 1. Tank body; 11. Carrier gas inlet; 12. Liquid inlet; 121. First liquid inlet; 122. Second liquid inlet; 13. Aqueous phase outlet; 14. Organic phase overflow outlet; 15. Receiving cavity; 2. Drainage structure; 21. Guiding channel; 3. Cleaning device; 31. Cleaning scraper; 311. Adhesive wall; 312. Fixing wall; 313. Guide wall; 32. Drive component; 321. Output shaft; 33. Mounting component; 331. Guide port; 332. Storage cavity; 4. Overflow baffle; 5. Auxiliary separation mechanism; 51. Vibrator; 511. Power component; 512. Vibration spring; 52. Separation net. Detailed Implementation

[0027] To more clearly illustrate the overall concept of this application, a detailed explanation is provided below with reference to the accompanying drawings.

[0028] Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below. It should be noted that, unless otherwise specified, the embodiments of this application and the features thereof can be combined with each other.

[0029] Furthermore, it should be understood in the description of this application that the terms "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0030] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0031] In this application, unless otherwise expressly specified and limited, the "above" or "below" of the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. In the description of this specification, references to terms such as "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples.

[0032] like Figure 1 , Figure 2 , Figure 3As shown, this application discloses an air flotation device, including a tank 1 and a flow guiding structure 2. The tank 1 is provided with a receiving cavity 15, and the flow guiding structure 2 is disposed in the receiving cavity 15. The tank 1 is provided with a carrier gas inlet 11, a liquid inlet 12, a water phase outlet 13, and an organic phase overflow outlet 14. The carrier gas inlet 11 is disposed at the top of the tank 1, the water phase outlet 13 is disposed below the flow guiding structure 2, and the organic phase overflow outlet 14 is disposed above the flow guiding structure 2. The flow guiding structure 2 is provided with a guiding channel 21, the upper and lower sides of which are open structures. One end of the guiding channel 21 is adjacent to the liquid inlet 12, and the other end extends along a spiral path toward the central area of ​​the tank 1 to guide the liquid entering the receiving cavity 15 to form a swirling flow field. The organic phase in the liquid floats and separates under the action of the swirling flow field and is discharged through the organic phase overflow outlet 14. Some of the organic phase adheres to the inner wall of the guiding channel 21, and the separated water phase is discharged through the water phase outlet 13.

[0033] This application provides a flow guiding structure 2 within the receiving cavity 15 of the tank 1, with one end of the guiding channel 21 adjacent to the liquid inlet 12 and the other end extending along a spiral path towards the central region of the tank 1. When liquid enters the receiving cavity 15 from the liquid inlet 12, it flows along the spiral path under the guidance of the guiding channel 21, thereby forming a swirling flow field within the receiving cavity 15. Under the action of this swirling flow field, different phases in the liquid exhibit a radial separation tendency due to density differences, causing the less dense organic phase to gradually move towards the center of the swirling flow and float upwards. Simultaneously, during this movement towards the center, it coalesces through mutual collisions, thereby improving the aggregation efficiency of the organic phase. Furthermore, since the upper and lower sides of the guiding channel 21 are both open structures, the liquid can interact with the liquid from the vertical direction of the guiding channel 21 during the swirling flow. The bubbles in the containment cavity 15 are in full contact, allowing them to adhere to the organic phase and increase its buoyancy, thereby further promoting the separation of the organic phase. In addition, some organic phase can adhere to the inner wall of the guide channel 21 during the swirling flow, and gradually gather at the inner wall to form larger organic phase droplets or liquid films. Under the action of fluid shear force and buoyancy, they detach from the inner wall and move upward, thereby further agglomerating the organic phase that was originally dispersed in the liquid and accelerating its upward movement. Since the synergistic effect of swirling flow and air flotation can accelerate the agglomeration and upward separation process of the organic phase, the guiding time required for the liquid to achieve effective separation in the equipment is shortened. This allows the equipment to adopt a more compact structural design while meeting the same processing capacity, which is beneficial to reduce the overall size of the equipment and reduce the space occupied by the equipment.

[0034] In this application, the drainage structure 2 can be configured in any of the following embodiments: Implementation method one: such as Figure 1 , Figure 2 , Figure 3As shown, the flow guiding structure 2 is spirally arranged to form a guiding channel 21. The liquid inlet 12 is located on the side wall of the tank 1. The starting end of the guiding channel 21 is located on the liquid outlet path of the liquid inlet 12. The flow guiding structure 2 has a connecting end that connects to the inner wall of the tank 1. The outer side of the flow guiding structure 2 at the connecting end is tangential to the inner wall of the tank 1, so that the liquid entering the receiving cavity 15 flows spirally along the flow guiding structure 2. Figure 3 In the middle, along the vertical direction, the connecting end of the drainage structure 2 is located below the liquid inlet 12, corresponding to... Figure 1 In the middle, the connecting end of the drainage structure 2 is located in front of the liquid inlet 12, and the liquid inlet 12 is inclined tangentially along the inner wall of the receiving cavity 15.

[0035] Those skilled in the art will understand that, in this application, as Figure 3 As shown, liquid continuously enters the receiving cavity 15 through the inlet 12. The liquid generates a counterclockwise dynamic flow field through the drainage structure 2. Simultaneously, some liquid fills the space between the drainage structure 2 and the receiving cavity 15, forming a static flow field between the inner wall of the receiving cavity 15 and the drainage structure 2. The magnitude of the static flow field is adjusted by changing the gap between the inner wall of the receiving cavity 15 and the drainage structure 2. Furthermore, through the action of the dynamic flow field, counterclockwise dynamic flow fields are formed both above and below the drainage structure 2.

[0036] By setting the flow guide structure 2 in a spiral shape to form a guide channel 21, and placing the starting end of the guide channel 21 on the liquid outlet path of the liquid inlet 12, when the liquid enters the receiving cavity 15 from the liquid inlet 12 located on the side wall of the tank body 1, the liquid can directly enter the guide channel 21 and flow along the spiral path of the flow guide structure 2, thereby being guided to form a swirling flow in the early stage of entering the receiving cavity 15. Furthermore, since the flow guide structure 2 has a connection end connected to the inner wall of the tank body 1, and the outer side of the flow guide structure 2 at the connection end is tangentially set to the inner wall of the tank body 1, the liquid can flow along the tangential direction of the inner wall of the tank body 1 after entering the receiving cavity 15, thereby making it easier to form a stable swirling flow field and avoiding the liquid directly impacting the inside of the tank body 1 and causing turbulent flow. In this swirling flow process, it is beneficial to improve the rotational stability of the liquid in the receiving cavity 15, thereby enhancing the swirling separation effect and promoting the stratification separation of different phases in the liquid, and improving the separation efficiency of the organic phase.

[0037] Furthermore, the cavity 15 is provided with a support member for supporting the drainage structure 2. There are multiple support members, which are arranged sequentially along the circumference of the cavity 15. One end of the support member is connected to the cavity wall of the cavity 15, and the other end is connected to the drainage structure 2.

[0038] As a preferred embodiment, the drainage structure 2 is configured as follows: Figure 3As shown, the inner diameter of the connecting end of the drainage structure 2 is r1, the inner diameter of the receiving cavity 15 is R, r1=k*R, and the value range of k is: 0.14≤k≤0.25; the inner diameter of the end of the drainage structure 2 is r2, r2=m*R, and the value range of m is: 0.8≤m≤0.9; the rotation pitch of the drainage structure 2 is a constant pitch l, l=n*R, and the value range of n is: 0.07≤n≤0.12; the number of turns of the drainage structure 2 is 3-5 turns.

[0039] Those skilled in the art will understand that different numbers of turns of the drainage structure 2 are selected based on the guiding time of the liquid within the guiding channel 21. Meanwhile, the inner diameter r1 refers to the distance from the connecting end of the drainage structure 2 to the center of the vortex, and the inner diameter r2 refers to the distance from the end of the drainage structure 2 to the center of the vortex.

[0040] Implementation Method Two: This implementation method is not illustrated. The drainage structure consists of a spirally arranged guide plate. The guiding channel includes a first channel and a second channel. The first channel is formed by the guide plate and the cavity wall of the receiving chamber. The second channel is formed by adjacent guide plates. Liquid enters the second channel from the first channel. For ease of understanding... Figure 3 To illustrate the structure, in Embodiment 2, the connecting end of the drainage structure is located above the inlet in the vertical direction.

[0041] In Embodiment 1, the cleaning setup for the guide channel 21 can be any of the following embodiments: Example 1: As Figure 1 , Figure 2 , Figure 3 As shown, the air flotation equipment also includes a cleaning device 3. The flow guiding structure 2 extends along the axial direction of the tank body 1. The cleaning device 3 includes a cleaning scraper 31, which is disposed on the inner wall of the guide channel 21 near the vortex center. The cleaning scraper 31 is movable relative to the flow guiding structure 2 to clean the organic phase attached to the guide channel 21. Since the diversion structure 2 extends axially along the tank body 1, the guide channel 21 has a large extension length in the axial direction, thereby increasing the guiding area for the liquid entering the receiving cavity 15. This allows more liquid to flow along the guide channel 21 after entering the receiving cavity 15, which is beneficial for forming a stable swirling flow field. During the process of liquid forming a swirling flow, some organic phase can adhere to the inner wall of the guide channel 21 near the swirling center. By setting up the cleaning device 3 and placing the cleaning scraper 31 on the inner wall of the guide channel 21 near the swirling center, and the cleaning scraper 31 being movable relative to the diversion structure 2, the organic phase adhering to the inner wall of the guide channel 21 can be scraped off during the movement, reducing the adhesion residue of organic phase on the inner wall. This allows for cleaning of the inner wall during equipment operation, which helps to shorten the cleaning and maintenance time interval between equipment processing cycles.

[0042] Preferably, the height of the drainage structure 2 is h1, and the height of the receiving cavity 15 is H, where h1 = e * H, and the value of e ranges from 0.5 to e ≤ 0.6. Combined with the arrangement of the drainage structure 2 in Embodiment 1, this allows the air flotation equipment to process 120-420 tons of air. / h, when the processing volume is greater than 420 At a rate of / h, multiple air flotation devices are connected in series to improve processing efficiency.

[0043] Example 2: This Example 2 is not illustrated. The difference from Example 1 is that multiple cleaning scrapers are provided. The multiple cleaning scrapers are spaced apart along the extension direction of the guide channel and move relative to the drainage structure to clean the organic phase attached to the inner wall of the guide channel.

[0044] In Embodiment 1, the cleaning scraper 31 can be configured in any of the following specific examples: Specific example 1: if Figure 1 , Figure 2 , Figure 3 As shown, the cleaning device 3 also includes a drive unit 32, a cleaning scraper 31 arranged along the axial direction of the guide channel 21, and an output shaft 321 of the drive unit 32 connected to the cleaning scraper 31. The drive unit 32 drives the cleaning scraper 31 to move along the axial direction of the tank 1.

[0045] By setting a drive component 32, the output shaft 321 of the drive component 32 is connected to the cleaning scraper 31. Under the driving action of the drive component 32, the cleaning scraper 31 can be moved along the axial direction of the tank body 1, so that the cleaning scraper 31 can scrape and clean the inner wall of the guide channel 21 along the axial direction of the drainage structure 2, so that the organic phase attached to different positions on the inner wall can be effectively cleaned, thereby improving the cleaning range and cleaning effect of the cleaning scraper 31 on the inner wall of the guide channel 21.

[0046] Furthermore, the drive unit 32 is disposed outside the tank body 1, and the tank body 1 is provided with a guide hole that connects to the receiving cavity 15. The output shaft 321 passes through the guide hole and enters the receiving cavity 15 to connect with the cleaning scraper 31.

[0047] Furthermore, such as Figure 1 , Figure 2 , Figure 3 , Figure 4As shown, the cleaning device 3 also includes a mounting member 33 disposed at the bottom of the cleaning scraper 31. The cleaning scraper 31 is fixed to the mounting member 33, and the cleaning scraper 31 has a contact wall 311 that fits against the inner wall of the guide channel 21. By providing the mounting member 33 at the bottom of the cleaning scraper 31 and fixing the cleaning scraper 31 to the mounting member 33, the cleaning scraper 31 can be stably installed on the cleaning device 3, thereby helping to ensure the structural stability of the cleaning scraper 31 during movement. At the same time, the cleaning scraper 31 has a contact wall 311 that fits against the drainage structure 2, so that the cleaning scraper 31 can maintain contact with the inner wall of the guide channel 21 during movement, thereby more thoroughly scraping away the organic phase attached to the inner wall of the guide channel 21 and improving the cleaning effect.

[0048] As a preferred option, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown, the cleaning scraper 31 includes a fixed wall 312 connected to the mounting member 33 and a guide wall 313 connecting the fixed wall 312 and the fitting wall 311. The mounting member 33 has a storage cavity 332 and a guide opening 331 communicating with the storage cavity 332. The guide wall 313 is inclined to guide the organic phase attached to the guide channel 21 to the guide opening 331. Preferably, the guide wall 313 extends obliquely downward, and the angle between the guide wall 313 and the inner wall of the guide channel 21 is α, where α ranges from 30° to 45°. The mounting member 33 has a positioning groove for mounting the fixed wall 312. By providing a fixed wall 312 connected to the mounting component 33 on the cleaning scraper 31, and a guide wall 313 between the fixed wall 312 and the fitting wall 311, the organic phase adhering to the inner wall of the guide channel 21 can be detached from the inner wall under the scraping action of the fitting wall 311 when the cleaning scraper 31 scrapes the inner wall of the guide channel 21, and move in an inclined direction under the guidance of the guide wall 313. At the same time, by providing a storage cavity 332 in the mounting component 33 and a guide port 331 communicating with the storage cavity 332, the organic phase moving under the guidance of the guide wall 313 can enter the storage cavity 332 for temporary collection, which is conducive to the centralized introduction and storage of the scraped organic phase, and avoids the organic phase from adhering to the inner wall of the guide channel 21 again during the cleaning process.

[0049] Specific Example 2: This specific example 2 is not illustrated. The difference from specific example 1 is that the cleaning scraper is arranged along the axial direction of the tank and can move along the axial direction of the guide channel.

[0050] In this application, the organic phase overflow port 14 can be configured in any of the following embodiments: Implementation Method 3: For example Figure 1 , Figure 2As shown, the organic phase overflow port 14 is located at the upper part of the tank 1, and the aqueous phase outlet 13 is located at the bottom of the tank 1. An overflow baffle 4 is provided above the drainage structure 2. One end of the overflow baffle 4 is fixedly connected to the inner wall of the receiving cavity 15, and the other end extends upward in an arc shape towards the axis of the tank 1. The connection end between the overflow baffle 4 and the inner wall of the receiving cavity 15 is located below the organic phase overflow port 14. By setting the organic phase overflow port 14 at the upper part of the tank 1 and setting the aqueous phase outlet 13 at the bottom of the tank 1, the organic phase that floats upward under the action of swirling flow can gather at the upper part of the tank 1 and be discharged through the organic phase overflow port 14, while the denser aqueous phase moves to the lower part of the tank 1 and is discharged through the aqueous phase outlet 13, which is conducive to achieving the stratified discharge of the organic phase and the aqueous phase. Meanwhile, an overflow baffle 4 is set above the drainage structure 2, with one end of the overflow baffle 4 fixedly connected to the inner wall of the receiving cavity 15, and the other end extending upward in an arc shape toward the axis of the tank 1, so that the organic phase floating to the area above the drainage structure 2 is gathered under the guidance of the arc-shaped overflow baffle 4; furthermore, the connection end of the overflow baffle 4 to the inner wall of the receiving cavity 15 is located below the organic phase overflow port 14, so that the floating organic phase can be guided by the overflow baffle 4 during the flow process and move toward the organic phase overflow port 14, thereby facilitating the discharge of the organic phase through the organic phase overflow port 14.

[0051] Implementation Method 4: This implementation method 4 is not illustrated. The difference from implementation method 3 is that there are multiple organic phase overflow ports, which are arranged sequentially at intervals along the circumference of the receiving cavity.

[0052] In this application, the auxiliary filtration setup of the air flotation device can be any of the following embodiments: Implementation Method 5: (e.g.) Figure 1 , Figure 2 As shown, an auxiliary separation mechanism 5 is provided below the flow-guiding structure 2. The auxiliary separation mechanism 5 includes a vibrator 51 and a separation net 52. The separation net 52 is located between the water phase outlet 13 and the flow-guiding structure 2. The vibrator 51 drives the separation net 52 to vibrate, causing the organic phase attached to the separation net 52 to coalesce and float upward. By setting the auxiliary separation mechanism 5 below the flow-guiding structure 2 and placing the separation net 52 between the water phase outlet 13 and the flow-guiding structure 2, the liquid flowing from below the flow-guiding structure 2 to the water phase outlet 13 area can pass through the separation net 52, so that the organic phase in the liquid adheres to the separation net 52 when passing through it. At the same time, by setting the vibrator 51 and driving the separation net 52 to vibrate, the organic phase attached to the separation net 52 collides and gradually coalesces into larger organic phase droplets under the vibration. The coalesced organic phase moves upward under the action of buoyancy and re-enters the separation area above, which is conducive to promoting further aggregation and floating separation of the organic phase and improving the oil-water separation effect of the air flotation equipment.

[0053] Furthermore, such as Figure 1 , Figure 2 As shown, the vibrator 51 includes a power component 511 and a vibration spring 512. One end of the vibration spring 512 is connected to the drive shaft of the power component 511, and the other end is connected to the separation net 52. The power component 511 is located on the outside of the tank body 1, and the drive shaft passes through a metal tube and is connected to the vibration spring 512.

[0054] Implementation Method Six: This implementation method six is ​​not illustrated. The auxiliary separation mechanism includes a vibrator and multiple separation nets. The multiple separation nets are spaced apart along the axial direction of the tank between the water phase outlet and the diversion structure. The vibrator drives the multiple separation nets to vibrate, thereby increasing the probability of collision and aggregation of the organic phase, and thus promoting the floating of the organic phase.

[0055] Implementation Method 7: This implementation method 7 is not illustrated. The auxiliary separation mechanism includes a rotating support and a separation net. The separation net is rotatably disposed between the aqueous phase outlet and the diversion structure. The rotational motion causes the organic phase attached to the separation net to be disturbed and aggregated, thereby promoting the floating and separation of the organic phase.

[0056] In this application, the liquid inlet 12 can be configured in any of the following embodiments: Implementation method eight: such as Figure 1 , Figure 2 As shown, the liquid inlet 12 includes at least a first liquid inlet 121 and a second liquid inlet 122. The first liquid inlet 121 is located at a height corresponding to the top of the drainage structure 2, and the second liquid inlet 122 is located at a height corresponding to the middle of the drainage structure 2. The first liquid inlet 121 can be positioned to correspond to the top of the drainage structure 2 by having its upper edge aligned with the top of the drainage structure 2, or by having the top of the drainage structure 2 located in the middle or lower part of the first liquid inlet 121. Liquid enters the flow-guiding structure 2 through the first inlet 121 at the top or the second inlet 122 in the middle. Users can select inlets 12 at different heights according to separation requirements, so that the liquid forms a corresponding initial liquid level in the flow-guiding structure 2 and flows along the spirally extended guide channel 21 to form a swirling flow field. By selecting the position of the inlet 12, not only can the radial distribution and component force of the liquid in the swirling flow be controlled, but the swirling flow intensity can also be changed to make the swirling flow state more uniform or more intense, so as to adapt to different liquid properties and separation requirements.

[0057] Furthermore, a third liquid inlet and a fourth liquid inlet can be provided. The lower edge of the fourth liquid inlet is aligned with the lower edge of the drainage structure 2, and the third liquid inlet is located between the second liquid inlet 122 and the fourth liquid inlet.

[0058] Embodiment Nine: This embodiment nine is not illustrated. The air flotation device further includes a sliding plate movably disposed at the liquid inlet. The sliding plate moves along the liquid inlet to change the size and height of the liquid inlet. Two sliding plates are provided, and the two sliding plates are spaced apart to form the liquid inlet.

[0059] By setting a movable slide plate at the liquid inlet and moving the slide plate along the liquid inlet, the opening size of the liquid inlet can be adjusted by changing the position of the slide plate, so that the liquid flow rate entering the containment cavity can be adjusted. This is beneficial for controlling the liquid flow rate entering the air flotation equipment according to the actual processing conditions and for maintaining the stability of the swirling flow state in the containment cavity.

[0060] Implementation Method 10: This implementation method is not illustrated. The air flotation equipment is provided with multiple liquid inlets. Along the axial direction of the tank, the multiple liquid inlets are arranged at intervals, and the diameters of the liquid inlets are different.

[0061] In this application, the liquid entering tank 1 can be configured in any of the following embodiments: Implementation method 11: The liquid is a mixture of gas-water mixture and produced water. Before the liquid inlet 12, the gas-water mixture and produced water are premixed in the delivery pipeline or storage tank.

[0062] Implementation method 12: There are at least two inlets 12, namely a gas-water mixture inlet and a produced water inlet, with the gas-water mixture inlet being lower than the produced water inlet.

[0063] This application also discloses a control method applied to the air flotation device disclosed in this application, such as... Figure 5 As shown, the control methods include: Obtain the concentration of the organic phase of the liquid to be treated entering the air flotation device; The target guiding time of the drainage structure is determined based on the organic phase concentration. The required vortex intensity to be formed by the drainage structure is determined based on the target guidance time, and the parameters of the drainage structure are matched according to the vortex intensity. The target liquid flow rate entering the flotation device is determined based on the diversion structure and the target guidance time.

[0064] This application obtains the organic phase concentration of the liquid to be treated entering the air flotation device and determines the corresponding target guidance time based on the organic phase concentration, enabling the air flotation device to select appropriate separation time conditions for liquids with different organic phase concentrations. Furthermore, it determines the required swirling intensity of the guiding structure based on the target guidance time and matches the parameters of the guiding structure according to the swirling intensity, so that the liquid forms a swirling flow state adapted to the target guidance time within the guiding channel of the guiding structure, thereby enhancing the radial migration and upward separation process of the organic phase in the swirling field. Simultaneously, it determines the target liquid flow rate entering the air flotation device based on the guiding structure and the target guidance time, matching the actual guidance time of the liquid in the guiding channel with the target guidance time. This ensures separation efficiency while achieving coordinated matching of equipment operating parameters and structural parameters, improving the separation stability and processing efficiency of the air flotation device under different organic phase concentration conditions.

[0065] Determining the corresponding target guidance time based on organic phase concentration includes: When C≥300mg / L, the target guiding time of the liquid in the drainage structure is controlled to be 9-10s; When 180 mg / L ≤ C < 300 mg / L, the target guiding time of the liquid in the drainage structure is controlled to be 5-7 seconds. When C < 180 mg / L, the target guiding time of the liquid in the drainage structure is controlled to be 4-5 seconds.

[0066] The required vortex intensity to be formed by the drainage structure is determined based on the target guidance time, and the drainage structure parameters are matched according to the vortex intensity, including: The required vortex enhancement level to be formed by the diversion structure is determined based on the target guidance time. The target guidance time is 9-10 seconds, and the vortex level is high. The target guidance time is 5-7 seconds, and the vortex level is medium. The target guidance time is 4-5 seconds, and the vortex level is low. Based on the parameters of the flow guidance structure matched with the swirl enhancement level, the swirl intensity is improved by reducing the helical pitch, increasing the number of helical turns, and reducing the initial inner diameter, so that the actual guidance time of the mixed liquid in the helical guidance channel formed by the flow guidance structure approaches the target guidance time.

[0067] The target liquid flow rate entering the flotation device is determined based on the drainage structure and the target induction time, including: The effective volume of the guide channel is V, where V = A * L, and A is the effective flow cross-sectional area of ​​the guide channel, and L is the length of the spiral guide path.

[0068] The target liquid flow rate is Q, Q= ; Where T represents the target guidance time.

[0069] For any parts not mentioned in this application, existing technologies may be used or referenced.

[0070] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0071] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. An air flotation device, characterized in that, The device includes a tank and a flow guiding structure. The tank has a receiving cavity, and the flow guiding structure is disposed in the receiving cavity. The tank has a carrier gas inlet, a liquid inlet, a water phase outlet, and an organic phase overflow outlet. The carrier gas inlet is located at the top of the tank, the water phase outlet is located below the flow guiding structure, and the organic phase overflow outlet is located above the flow guiding structure. The flow guiding structure has a guiding channel, the upper and lower sides of which are open. One end of the guiding channel is adjacent to the liquid inlet, and the other end extends along a spiral path toward the central region of the tank to guide the liquid entering the receiving cavity to form a swirling flow field. Under the action of the swirling flow field, the organic phase in the liquid floats and separates and is discharged through the organic phase overflow outlet. Some of the organic phase adheres to the inner wall of the guiding channel, and the separated water phase is discharged through the water phase outlet.

2. The air flotation device according to claim 1, characterized in that, The drainage structure is spirally arranged to form the guiding channel. The liquid inlet is located on the side wall of the tank. The starting end of the guiding channel is located on the liquid outlet path of the liquid inlet. The drainage structure has a connecting end that connects to the inner wall of the tank. The outer side of the drainage structure at the connecting end is tangential to the inner wall of the tank, so that the liquid entering the receiving cavity flows spirally along the drainage structure.

3. The air flotation device according to claim 2, characterized in that, The flotation device also includes a cleaning device. The flow-guiding structure extends axially along the tank body. The cleaning device includes a cleaning scraper, which is disposed on the inner wall of the guide channel near the vortex center. The cleaning scraper is movable relative to the flow-guiding structure to clean the organic phase adhering to the guide channel.

4. The air flotation device according to claim 3, characterized in that, The cleaning device further includes a drive unit, the cleaning scraper is arranged along the axial direction of the guide channel, the output shaft of the drive unit is connected to the cleaning scraper, and the drive unit drives the cleaning scraper to move along the axial direction of the tank.

5. The air flotation device according to claim 4, characterized in that, The cleaning device further includes a mounting component disposed at the bottom of the cleaning scraper, the cleaning scraper being fixed to the mounting component, and the cleaning scraper having a fitting wall that fits against the inner wall of the guide channel.

6. The air flotation device according to claim 5, characterized in that, The cleaning scraper includes a fixed wall connected to the mounting member and a guide wall connecting the fixed wall and the fitting wall. The mounting member has a storage cavity and a guide port communicating with the storage cavity. The guide wall is inclined to guide the organic phase attached to the guide channel to the guide port.

7. The air flotation device according to claim 1, characterized in that, The organic phase overflow port is located at the upper part of the tank, and the aqueous phase outlet is located at the bottom of the tank. An overflow baffle is provided above the drainage structure. One end of the overflow baffle is fixedly connected to the inner wall of the receiving cavity, and the other end extends upward in an arc towards the axis of the tank. The connection end of the overflow baffle and the inner wall of the receiving cavity is located below the organic phase overflow port.

8. The air flotation device according to claim 1, characterized in that, An auxiliary separation mechanism is provided below the flow-guiding structure. The auxiliary separation mechanism includes a vibrator and a separation net. The separation net is located between the aqueous phase outlet and the flow-guiding structure. The vibrator drives the separation net to vibrate, causing the organic phase attached to the separation net to aggregate and float.

9. The air flotation device according to claim 1, characterized in that, The liquid inlet includes at least a first liquid inlet and a second liquid inlet, the first liquid inlet being located at a height corresponding to the top of the drainage structure, and the second liquid inlet being located at a height corresponding to the middle of the drainage structure.

10. A control method applied to the air flotation device according to any one of claims 1 to 9, characterized in that, The control method includes: Obtain the organic phase concentration of the liquid to be treated entering the air flotation device; The target guiding time of the drainage structure is determined based on the organic phase concentration. The required vortex intensity to be formed by the drainage structure is determined based on the target guidance time, and the parameters of the drainage structure are matched according to the vortex intensity. The target liquid flow rate entering the air flotation device is determined based on the described flow structure and the target flow time.

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