A mixing apparatus for preparing supramolecular oil-free drag-reducing agents

Abstract

This invention relates to the field of fluid drag-reducing material preparation technology, specifically to a mixing device for preparing supramolecular oil-free drag-reducing agents. The device includes a main mixing tank equipped with a stirring rack, a feed port, and a discharge port. It also includes a submerged premixing feeding mechanism connected to the main mixing tank. The submerged premixing feeding mechanism includes: a sealed mixing shell with a central mixing cylinder and a conical collecting hopper located below the central mixing cylinder; and a liquid centrifugal disc disposed within the central mixing cylinder. A liquid feed pipe is connected to a liquid feeder located at the center of the liquid centrifugal disc. This invention uses the liquid centrifugal disc and the powder centrifugal disc to form opposing liquid and powder curtains, respectively, allowing the powder to be pre-wetted and initially dispersed before entering the main mixing tank. The resulting wet material is then transported below the liquid surface in the main mixing tank. Compared to directly pouring powder from above the liquid surface, this reduces dust dispersion, liquid surface floating, and agglomeration problems during feeding.

Description

Technical Field

[0001] This invention relates to the field of fluid drag-reducing material preparation technology, and in particular to a mixing apparatus for preparing supramolecular oil-free drag-reducing agents. Background Technology

[0002] Supramolecular oil-free drag reducers are a class of water-based treatment agents used to reduce fluid transport resistance. They are usually made from base liquid, functional powders and other additives through processes such as feeding, mixing and dispersion. During the production process, it is necessary to uniformly disperse the powdered components with drag-reducing effect in the liquid phase material, and to promote full contact of each component through continuous stirring, so as to form a drag reducer product with suitable flowability and dispersion.

[0003] Currently, powders are usually poured directly from above the liquid surface in the mixing tank. Due to the small particle size and low bulk density of some powders, dust is easily generated during feeding and floats on the liquid surface or adheres to the tank wall. Some powders absorb liquid quickly on the surface after contact with the liquid, while the inside remains dry, which easily forms clumps that are wet on the outside and dry on the inside, increasing the difficulty of subsequent stirring and dispersion. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a mixing device for preparing supramolecular oil-free drag-reducing agents, so as to solve the problems of dust generation, floating and clumping caused by direct addition of powder during the preparation and mixing process of drag-reducing agents.

[0005] To achieve the above objectives, the present invention provides a mixing apparatus for preparing supramolecular oil-free drag-reducing agents, comprising a main mixing tank equipped with a stirring rack, a feeding port, and a discharging port, and further comprising a submersible premixing feeding mechanism connected to the main mixing tank, the submersible premixing feeding mechanism comprising: A sealed mixing shell, with a central mixing cylinder inside and a conical collecting hopper located below the central mixing cylinder; A liquid centrifuge disc is disposed inside the central mixing cylinder. A liquid feed pipe is connected to a liquid feeder disposed at the center of the liquid centrifuge disc. The outer edge of the liquid centrifuge disc is provided with a downward guide lip. A powder centrifugal disc is coaxially positioned below the liquid centrifugal disc. A sealed powder silo supplies material to the center of the powder centrifugal disc through a powder conveying pipe. The outer edge of the powder centrifugal disc is provided with an upward throwing lip. A dual-axis drive assembly includes an outer hollow shaft connected to the liquid centrifugal disc, an inner drive shaft connected to the powder centrifugal disc, and a liquid disc drive motor and a powder disc drive motor that drive the outer hollow shaft and the inner drive shaft to rotate respectively. The outer hollow shaft is coaxially sleeved on the outer periphery of the inner drive shaft. An annular powder-liquid confluence chamber is formed around the two centrifuge discs; The reflux assembly includes a wet material collection chamber formed in a conical hopper and a wet material outlet, a reflux conveying pipe, a reflux conveying pump and a submerged reflux pipe connected in sequence. The submerged reflux pipe extends into the main mixing tank and is provided with a reflux distribution port located below the liquid surface.

[0006] Furthermore, the liquid feed pipe is equipped with a feed pump, and the liquid feeder includes a central liquid inlet connector, a liquid buffer chamber, an annular liquid equalization chamber, and a liquid guide shroud; The liquid feed pipe is connected to the liquid buffer chamber through the central liquid inlet connector. The liquid buffer chamber is connected to the annular liquid equalization chamber arranged around its outer periphery. The bottom of the annular liquid equalization chamber is provided with a number of liquid equalization holes spaced circumferentially towards the liquid centrifuge plate. The liquid guide cover is provided above the central area of ​​the annular liquid equalization chamber and the liquid centrifuge plate to guide the liquid discharged through the liquid equalization holes to the plate surface of the liquid centrifuge plate.

[0007] Furthermore, the liquid centrifuge disc includes a liquid-bearing disc surface, a film-forming ring, an anti-drip ring, and a liquid-separating plate at the bottom of the disc. The liquid-bearing disc surface is a shallow cone that gradually slopes downward from the center to the outer edge. The downward guide lip is arranged around the outer edge of the liquid-bearing disc surface and extends downward. The film-forming ring is circumferentially disposed on the outer periphery of the liquid-bearing disk surface to form an annular liquid film; the anti-drip ring is disposed at the lower end of the downward guide lip to prevent the liquid from flowing back to the bottom of the liquid centrifuge disk. The bottom baffle plate is located below the liquid-bearing plate and surrounds the outer hollow shaft to isolate the liquid centrifugal disc from the powder centrifugal disc.

[0008] Furthermore, the top of the sealed powder silo is provided with a sealed feeding port, and the bottom is provided with a conical conveying hopper, the discharge end of which is connected to the powder conveying pipe; The lower end of the powder conveying pipe extends to the central area of ​​the powder centrifugal disc, and the annular powder distribution cover is installed on the outside of the lower end of the powder conveying pipe and forms an annular powder distribution channel with the powder centrifugal disc. The annular powder distribution channel is equipped with a powder distribution scraper that rotates synchronously with the powder centrifugal disc, which is used to spread the powder discharged from the powder conveying pipe along the circumference of the powder centrifugal disc.

[0009] Furthermore, the powder centrifugal disc includes a powder bearing disc surface, radial powder-dispensing blades, and a throwing ring. The powder bearing disc surface is a shallow cone shape that extends inclinedly from the center to the outer edge. Several radial powder-dispensing blades are arranged at intervals along the circumference of the powder bearing disc surface and extend from its central area to the outer edge. The upward throwing lip is arranged around the outer edge of the powder carrying plate and tilted upward, and the throwing ring is arranged on the upper edge of the upward throwing lip so that the powder forms an upward throwing annular powder curtain.

[0010] Furthermore, an annular guide tube is provided on the outside of the annular powder-liquid confluence cavity. The annular guide tube is arranged around the outside of the liquid centrifugal disc and the powder centrifugal disc, and defines the annular powder-liquid confluence cavity between the outer edges of the two centrifugal discs. The inner wall of the annular guide tube is provided with an arc-shaped guide surface that extends inclined toward the conical hopper. The arc-shaped guide surface is provided with an anti-rebound ring to prevent the powder-liquid mixture from rebounding and flowing back.

[0011] Furthermore, the annular powder-liquid confluence cavity is also provided with an annular compensation pipe. The annular compensation pipe has several spray holes along its circumference facing the powder-liquid confluence area for supplementing the annular powder-liquid confluence cavity with sprayed liquid. The annular compensation pipe is connected to the liquid feed pipe.

[0012] Furthermore, the wet material collecting chamber is located below the annular powder-liquid confluence chamber, and the inner wall of the wet material collecting chamber forms a conical guide wall that gradually narrows towards the wet material outlet; The wet material outlet is located at the bottom of the wet material collection chamber and is connected to the return conveying pipe. The return conveying pipe is equipped with a return conveying pump for returning the wet material discharged from the wet material collection chamber.

[0013] Furthermore, the conical guide wall is provided with an anti-snagging scraper that can move along its surface. The anti-snagging scraper is set close to the conical guide wall and can move circumferentially along the surface of the conical guide wall to scrape off the wet material adhering to the conical guide wall. The anti-clogging scraper is connected to the inner drive shaft via a speed reducer located at the center of the wet material collection cavity, so that the inner drive shaft drives the anti-clogging scraper to rotate at a low speed.

[0014] Furthermore, the wet material collection chamber is provided with an annular flushing pipe, which has several flushing holes spaced around the circumference and facing the conical guide wall. The annular flushing pipe is connected to the liquid feed pipe.

[0015] The beneficial effects of the present invention are as follows: As can be seen from the above description, the present invention provides a mixing device for preparing supramolecular oil-free drag-reducing agents. By forming a liquid curtain and a powder curtain moving in opposite directions through a liquid centrifugal disc and a powder centrifugal disc, the powder is pre-wetted and initially dispersed before entering the main mixing tank. The formed wet material is then transported to below the liquid surface of the main mixing tank. Compared with directly pouring the powder from above the liquid surface, this reduces dust dispersion, liquid surface floating, and material splashing during feeding. It also reduces the probability of the powder forming externally wet and internally dry clumps due to rapid surface liquid absorption. Submerged input also allows the premixed wet material to directly enter the flow field inside the tank and continue to disperse under the stirring action, reducing air entrainment and tank wall adhesion, making the powder addition and subsequent mixing process more stable. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the internal structure of the sealed hybrid shell according to an embodiment of the present invention; Figure 2 This is a front view of an embodiment of the present invention. Figure 3 This is a schematic diagram of the main mixing tank according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the submersible premixing feeding mechanism according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the sealed mixing shell according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the annular powder-liquid confluence cavity according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of the liquid centrifuge disc according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the liquid supply device according to an embodiment of the present invention; Figure 9 This is a schematic diagram of the structure of the powder centrifuge disc according to an embodiment of the present invention; Figure 10 This is a schematic diagram of the structure of the wet material collection cavity in an embodiment of the present invention.

[0018] The diagram is marked as follows: 1. Main mixing tank; 11. Stirring rack; 12. Feed port; 13. Discharge port; 2. Submersible premixing feeding mechanism; 21. Sealed mixing shell; 22. Central mixing cylinder; 23. Conical collecting hopper; 24. Submersible reflux pipe; 25. Reflux distribution port; 3. Liquid feed pipe; 31. Feeding pump; 32. Liquid feeder; 33. Central liquid inlet connector; 34. Liquid buffer chamber; 35. Annular equalization chamber; 36. Equalization hole; 37. Liquid guide hood; 4. Liquid centrifugal disc; 41. Liquid bearing disc surface; 42. Downward guide lip; 43. Film forming ring; 44. Anti-drip ring; 45. Bottom liquid baffle; 5. Sealed powder silo; 51. Conical conveying hopper; 52. Sealed feed port; 53. 54. Powder conveying pipe; 55. Annular powder distribution hood; 6. Powder distribution scraper; 7. Powder centrifugal disc; 8. Powder bearing disc surface; 9. Radial powder-dispensing blades; 10. Upward throwing lip; 11. Throwing ring; 12. Outer hollow shaft; 13. Inner drive shaft; 14. Liquid disc drive motor; 15. Powder disc drive motor; 16. Annular powder-liquid junction chamber; 17. Annular guide tube; 18. Arc-shaped guide surface; 19. Anti-rebound retaining ring; 10. Annular compensation pipe; 11. Spray hole; 12. Wet material collection chamber; 13. Conical guide wall; 14. Wet material outlet; 15. Reducer; 16. Anti-stick scraper; 17. Annular flushing pipe; 18. Flushing hole; 19. Return conveying pipe; 10. Return conveying pump. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0020] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0021] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 , Figure 10 As shown, a mixing apparatus for preparing a supramolecular oil-free drag reducer includes a main mixing tank 1 equipped with a stirring rack 11, a feeding port 12, and a discharging port 13, and also includes a submersible premixing feeding mechanism 2 connected to the main mixing tank 1. The submersible premixing feeding mechanism 2 includes: The sealed mixing shell 21 has a central mixing cylinder 22 and a conical hopper 23 located below the central mixing cylinder 22 inside; The liquid centrifuge disc 4 is set inside the central mixing cylinder 22. The liquid feed pipe 3 is connected to the liquid feeder 32 set at the center of the liquid centrifuge disc 4. The outer edge of the liquid centrifuge disc 4 is provided with a downward guide lip 42. The powder centrifugal disc 6 is coaxially arranged below the liquid centrifugal disc 4. The sealed powder silo 5 supplies material to the center of the powder centrifugal disc 6 through the powder conveying pipe 53. The outer edge of the powder centrifugal disc 6 is provided with an upward throwing lip 63. The dual-axis drive assembly includes an outer hollow shaft 7 connected to the liquid centrifugal disc 4, an inner drive shaft 71 connected to the powder centrifugal disc 6, and a liquid disc drive motor 72 and a powder disc drive motor 73 that drive the outer hollow shaft 7 and the inner drive shaft 71 to rotate respectively. The outer hollow shaft 7 is coaxially sleeved on the outer periphery of the inner drive shaft 71. The annular powder-liquid confluence chamber 8 is formed around the two centrifuge discs; The reflux assembly includes a wet material collection chamber 9 formed in a conical hopper 23 and a wet material outlet 92, a reflux conveying pipe 97, a reflux conveying pump 98 and a submerged reflux pipe 24 connected in sequence. The submerged reflux pipe 24 extends into the main mixing tank 1 and is provided with a reflux distribution port 25 located below the liquid surface.

[0022] In this embodiment, the main mixing tank 1 of the device is used to contain the liquid phase material of the supramolecular oil-free drag reducing agent. The stirring rack 11 is set inside the main mixing tank 1 and continuously stirs the material in the tank under the drive of the stirring mechanism. The feeding port 12 is used to add the base liquid or other components. The mixed material is discharged through the discharge port 13. The submerged premixing feeding mechanism 2 is connected to the main mixing tank 1 and is used to complete the pre-contact and pre-dispersion of the powder and liquid before the powder enters the main mixing tank 1, thereby reducing the dust and floating phenomenon generated when the powder is directly put into the liquid surface. The sealed mixing shell 21 forms a relatively closed premixing space. The middle mixing cylinder 22 is located inside the sealed mixing shell 21, and the conical collection hopper 23 is located below the middle mixing cylinder 22. The centrifugal dispersion, cross-wetting and wet material collection processes of powder and liquid are all carried out inside the sealed mixing shell 21, which helps to limit the outward diffusion of dust and allows the wet material formed during the premixing process to be concentrated into the conical collection hopper 23 along a predetermined path. The liquid centrifugal disc 4 is installed inside the central mixing cylinder 22. The liquid feed pipe 3 is connected to the liquid feeder 32 located at the center of the liquid centrifugal disc 4. The liquid is transported to the liquid feeder 32 through the liquid feed pipe 3, and then sent to the central area of ​​the liquid centrifugal disc 4 by the liquid feeder 32. When the liquid centrifugal disc 4 rotates, the liquid spreads from the center to the outer edge under the centrifugal action, forming a thin and continuous liquid layer. After the liquid reaches the outer edge of the liquid centrifugal disc 4, it changes its direction of movement through the downward guide lip 42 and forms a downward-moving annular liquid curtain towards the annular powder-liquid confluence cavity 8. The powder centrifugal disc 6 is coaxially positioned below the liquid centrifugal disc 4. The sealed powder hopper 5, located above the outer side of the sealed mixing shell 21, is used to store the drag-reducing agent powder to be added. The powder enters the powder conveying pipe 53 from the sealed powder hopper 5 and falls to the central area of ​​the powder centrifugal disc 6 through the powder conveying pipe 53. After the powder centrifugal disc 6 rotates, the powder moves towards the outer edge of the disc under centrifugal action. The powder that reaches the outer edge is guided upward by the upward throwing lip 63 and thrown upward, forming an upward-moving annular powder curtain around the powder centrifugal disc 6. The upward throwing lip 63 makes the direction of powder movement intersect with the downward-moving liquid curtain, thereby shortening the time when the powder is in an unwetted state. The liquid centrifugal disc 4 and the powder centrifugal disc 6 are driven by a dual-shaft drive assembly. The outer hollow shaft 7 is connected to the liquid centrifugal disc 4, and the inner drive shaft 71 is connected to the powder centrifugal disc 6. The outer hollow shaft 7 is coaxially sleeved on the outer circumference of the inner drive shaft 71. The liquid disc drive motor 72 drives the outer hollow shaft 7 to rotate through a speed changer, and the powder disc drive motor 73 drives the inner drive shaft 71 to rotate through another speed changer, so that the two centrifugal discs can obtain corresponding speeds. When the two drive motors run independently, the speeds of the two centrifugal discs can be adjusted according to the liquid flow rate, powder addition amount, and powder flow characteristics, so that the liquid curtain and powder curtain maintain a relatively stable confluence state. The annular powder-liquid confluence chamber 8 is formed around the liquid centrifugal disc 4 and the powder centrifugal disc 6. The downward liquid curtain generated by the liquid centrifugal disc 4 and the upward powder curtain generated by the powder centrifugal disc 6 meet in the annular powder-liquid confluence chamber 8. During the movement, the powder particles come into contact with the droplets or liquid film and are wetted, forming a preliminarily dispersed wet material. The powder and liquid adopt a counter-current confluence method, which can make the powder more fully wetted before entering the main mixing tank 1, reducing the possibility of dry powder falling into the liquid and forming a wet outside and dry inside agglomerate. An annular guide tube 81 is set outside the annular powder-liquid confluence chamber 8 to limit the radial movement range of the liquid curtain, powder curtain and wet material after confluence. The wet material formed by confluence gathers downward along the annular guide tube 81 under the action of gravity and guidance and enters the conical collection hopper 23. A wet material collection chamber 9 is formed inside the conical collection hopper 23. The wet material flows downward along the inclined wall of the conical collection hopper 23 and gathers to the wet material outlet 92. The wet material outlet 92 is connected in sequence to the return conveying pipe 97, the return conveying pump 98 and the submerged return pipe 24. When the return conveying pump 98 is running, the wet material enters the return conveying pipe 97 from the wet material collection chamber 9 through the wet material outlet 92, and then is transported to the main mixing tank 1 through the submerged return pipe 24. The submerged reflux pipe 24 extends into the main mixing tank 1, and the reflux distribution port 25 is located below the liquid surface of the main mixing tank 1. The premixed wet material enters the liquid phase in the tank directly through the reflux distribution port 25 and continues to disperse under the action of the flow field formed by the stirring rack 11. The submerged reflux method can reduce splashing and air entrainment caused by the wet material falling from above the liquid surface, and at the same time, it allows the pre-wetted material to enter the main liquid phase more quickly, which is beneficial to improving the stability of the subsequent mixing process. Through a continuous treatment process of closed premixing, counter-current wetting, centralized collection, and submerged reflux, the addition state of powder can be improved, and the probability of powder dispersion, floating, and agglomeration can be reduced.

[0023] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 and Figure 10 As shown, preferably, the liquid feed pipe 3 of the device is connected to the main mixing tank 1, and the feed pump 31 is installed on the liquid feed pipe 3 for continuously feeding liquid to the liquid feeder 32. The liquid feed pipe 3 is also equipped with a flow regulating valve and a liquid flow meter. By cooperating with the feed pump 31, the flow regulating valve and the liquid flow meter, the liquid supply can be adjusted according to the powder addition speed and the rotation speed of the liquid centrifugal disc 4, so that the powder-liquid ratio and liquid film state are kept within a suitable range. The liquid feeder 32 includes a central liquid inlet connector 33, a liquid buffer chamber 34, an annular liquid equalization chamber 35, and a liquid guide shroud 37. The liquid feed pipe 3 is connected to the liquid buffer chamber 34 through the central liquid inlet connector 33 and is rotatably connected to the main body of the liquid feeder 32 through the central liquid inlet connector 33. The liquid delivered by the feed pump 31 first enters the liquid buffer chamber 34. The liquid buffer chamber 34 temporarily stores and buffers the liquid to reduce the influence of feed pressure fluctuations on the liquid outlet state. The buffered liquid flows from the liquid buffer chamber 34 into the annular liquid equalization chamber 35 arranged around its outer periphery and is distributed circumferentially along the annular liquid equalization chamber 35. Multiple equalization holes 36 are spaced circumferentially at the bottom of the annular equalization chamber 35. Each equalization hole 36 faces the liquid centrifuge plate 4. The liquid entering the annular equalization chamber 35 is discharged downward through the multiple equalization holes 36, so that the liquid falls onto the liquid centrifuge plate 4 in a circumferentially dispersed manner. The liquid guide hood 37 is covered above the central area of ​​the annular equalization chamber 35 and the liquid centrifuge plate 4 to limit the liquid from splashing upward or outward and to guide the liquid discharged through the equalization holes 36 to the plate surface of the liquid centrifuge plate 4. The liquid centrifugal disk 4 includes a liquid-bearing disk surface 41, a film-forming ring 43, an anti-drip ring 44, and a bottom liquid-separating plate 45. The liquid-bearing disk surface 41 is a shallow cone that gradually slopes downward from the center to the outer edge. After the liquid falls into the central area of ​​the liquid-bearing disk surface 41, it flows outward along the shallow cone-shaped disk surface under the rotation of the liquid centrifugal disk 4, forming a continuous radial flow liquid layer. After the liquid reaches the outer edge of the disk surface, it passes through the film-forming ring 43 and forms an annular liquid film under circumferential constraint and centrifugal action. After the annular liquid film crosses the outer edge of the liquid-bearing disk surface 41, it moves downward along the downward guide lip 42, thereby forming an annular liquid curtain towards the annular powder-liquid confluence cavity 8, providing a relatively stable liquid coverage area for the confluence of powder and liquid. The liquid flows downward along the downward guide lip... After flowing to the lower end, the liquid detaches from the liquid centrifugal disk 4 and enters the annular powder-liquid junction cavity 8 under the blocking and separation action of the anti-drip ring 44. This reduces the backflow of liquid along the back of the downward guide lip 42 to the bottom of the liquid centrifugal disk 4. The bottom baffle plate 45 is installed below the liquid bearing disk surface 41 and arranged around the outer hollow shaft 7. It is used to form an isolation area between the liquid centrifugal disk 4 and the powder centrifugal disk 6. When a small amount of seepage or scattered droplets appear on the liquid bearing disk surface 41, the bottom baffle plate 45 can restrict the liquid from falling directly to the powder centrifugal disk 6, reducing the situation where the powder gets damp, adheres, or clumps on the powder centrifugal disk 6 in advance. This allows the powder to disperse outward along the powder centrifugal disk 6 and contact the annular liquid curtain in the annular powder-liquid junction cavity 8.

[0024] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 and Figure 10As shown, preferably, the sealed powder hopper 5 of the device is used to store the drag-reducing agent powder to be added. The drag-reducing agent powder can be added through the sealed feeding port 52 at the top. A twin-screw conveyor mechanism and a weighing metering structure can be set between the discharge end of the conical conveying hopper 51 at the bottom and the powder conveying pipe 53. When the twin-screw conveyor mechanism is running, the two screws jointly push the powder to move towards the powder conveying pipe 53. The powder conveying speed can be changed by adjusting the screw speed. The weighing metering structure is used to detect the amount of powder conveyed and can control the amount of powder added in combination with the running speed of the twin-screw conveyor mechanism, so that the powder supply speed can be matched with the liquid flow rate and mixing conditions. The discharge end of the conical conveying hopper 51 can also be directly connected to the powder conveying pipe 53, and the material is conveyed naturally by gravity. The amount of material conveyed can be adjusted by adjusting the speed of the powder centrifugal disc 6. The powder conveying pipe 53 is vertically arranged, with its upper end receiving the powder discharged from the twin-screw conveyor and its lower end extending to the central area of ​​the powder centrifugal disc 6. Under the action of gravity, the powder falls along the powder conveying pipe 53 onto the powder centrifugal disc 6. An annular powder distribution cover 54 is installed on the outer side of the lower end of the powder conveying pipe 53, forming an annular powder distribution channel between the annular powder distribution cover 54 and the powder centrifugal disc 6. After the powder discharged from the powder conveying pipe 53 enters the annular powder distribution channel, it is restricted by the annular powder distribution cover 54 and is not easily dispersed directly upwards. A powder distribution scraper 55 is installed in the annular powder distribution channel. The powder distribution scraper 55 rotates synchronously with the powder centrifugal disc 6. After the powder falls into the central area of ​​the powder centrifugal disc 6, the powder distribution scraper 55 rotates with the disc and pushes the powder to spread out in the circumferential direction, so that the concentrated powder falls into a relatively uniform annular material layer. The powder distribution scraper 55 can also continuously move the powder in the annular powder distribution channel to reduce the accumulation or adhesion of powder in the central area, and provide relatively uniform initial conditions for the subsequent radial dispersion of powder. The powder centrifugal disc 6 includes a powder bearing disc surface 61, radial powder-dispensing blades 62, and a material-throwing ring 64. The powder bearing disc surface 61 is a shallow cone shape that extends from the center to the outer edge. After the powder is spread circumferentially, it moves from the central area to the outer edge under the centrifugal force generated by the rotation of the disc and the guiding force of the inclined disc surface, forming a continuous powder conveying state. Several radial powder-dispensing blades 62 are distributed circumferentially along the powder-carrying disc surface 61 and extend from the central area to the outer edge. When the powder moves outward, the radial powder-dispensing blades 62 dispense and separate the powder, reducing the local slippage, aggregation, or clumping of the powder on the disc surface. Each radial powder-dispensing blade 62 can also divide the powder into multiple circumferential conveying areas, so that the powder maintains a relatively uniform circumferential distribution before reaching the outer edge of the disc. After the powder reaches the outer edge of the powder bearing plate 61, it changes its direction of movement along the upward throwing lip 63 and moves upward. Then it passes the edge of the throwing ring 64 and leaves the plate, forming an upward-thrown annular powder curtain, so that the powder forms a continuous throwing area in the circumference, which facilitates the convergence of the annular powder curtain and the downward-moving annular liquid curtain.

[0025] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 and Figure 10 As shown, preferably, the annular guide tube 81 of the device is arranged around the outside of the liquid centrifugal disc 4 and the powder centrifugal disc 6, and is spaced from the outer edge of the two centrifugal discs, thereby defining the formation of an annular powder-liquid confluence cavity 8. The annular liquid curtain generated by the liquid centrifugal disc 4 moves downward and the annular powder curtain generated by the powder centrifugal disc 6 moves upward. The two come into contact with each other in the annular powder-liquid confluence cavity 8, so that the powder particles are wetted by the liquid during the throwing process. The annular guide tube 81 can limit the radial diffusion range of the liquid and powder, reduce the powder from drifting into other areas inside the sealed mixing shell 21, and concentrate the powder-liquid confluence process on the periphery of the two centrifugal discs. After the liquid curtain and powder curtain enter the annular powder-liquid confluence cavity 8, they form a relatively concentrated confluence area under the containment effect of the annular guide cylinder 81. The powder particles gradually form a powder-liquid mixture after contacting the liquid droplets. The annular guide cylinder 81 is used to receive the powder-liquid mixture formed within the annular powder-liquid confluence cavity 8. An arc-shaped guide surface 82 is provided on the inner wall of the annular guide cylinder 81, extending obliquely towards the conical collecting hopper 23. After the powder-liquid mixture contacts the annular guide cylinder 81, it flows towards the conical collecting hopper 23 under the guidance of gravity and the arc-shaped guide surface 82. The arc-shaped guide surface 82 is equipped with... The anti-rebound baffle ring 83 extends circumferentially along the annular guide tube 81 and protrudes from the arc-shaped guide surface 82. After the powder-liquid mixture with a certain speed falls onto the arc-shaped guide surface 82, the anti-rebound baffle ring 83 blocks the material that bounces back or splashes back along the arc-shaped guide surface 82, causing the material to fall back onto the arc-shaped guide surface 82 and continue to move towards the conical collection hopper 23. This structure can reduce the situation where the powder-liquid mixture bounces back to the annular powder-liquid junction cavity 8 or near the two centrifugal discs, and reduce the possibility of wet material adhering to the edge of the centrifugal disc and interfering with the formation of the powder curtain and liquid curtain. An annular compensation pipe 84 is also installed in the annular powder-liquid confluence chamber 8. The annular compensation pipe 84 is arranged around the annular guide cylinder 81 and is connected to the liquid feed pipe 3. Part of the liquid transported by the liquid feed pipe 3 enters the annular compensation pipe 84 and is then sprayed onto the powder-liquid confluence area by multiple spray holes 85 arranged at intervals around the circumference. The multiple spray holes 85 can replenish the liquid from different circumferential positions, so that the powder that has not been in full contact with the annular liquid curtain can be re-wetted. This helps to improve the consistency of the circumferential wetting state in the annular powder-liquid confluence chamber 8. In addition, the replenished liquid can also flush the wet material attached to the inner wall of the annular guide cylinder 81 and the vicinity of the confluence area, and allow the wet material to enter the annular guide cylinder 81 with the liquid flow, thereby reducing local material adhesion. By combining centralized convergence, circumferential liquid replenishment, arc-shaped material guiding, and rebound blocking, the powder wetting and wet material collection process can be improved, reducing powder dispersion, wet material splashing, and localized adhesion.

[0026] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 and Figure 10 As shown, preferably, the wet material collecting chamber 9 of the device is located below the annular powder-liquid confluence chamber 8, and is used to receive the wet material formed by the confluence of powder and liquid. The inner wall of the wet material collecting chamber 9 forms a conical guide wall 91. The conical guide wall 91 gradually contracts from top to bottom toward the wet material outlet 92. After the wet material falls into the wet material collecting chamber 9, it concentrates towards the bottom along the conical guide wall 91 under the action of gravity, which can reduce the wet material from being stuck at the edge of the chamber and provide guidance for the continuous discharge of the wet material. The wet material outlet 92 is located at the bottom of the wet material collection chamber 9 and is connected to the return conveying pipe 97. The return conveying pump 98 is installed on the return conveying pipe 97. When the return conveying pump 98 is running, it forms a conveying action at the wet material outlet 92, so that the collected wet material enters the return conveying pipe 97 and is sent to the main mixing tank 1 along the return conveying pipe 97. The anti-snagging scraper 94 is arranged close to the conical guide wall 91 and is adapted to the inclined shape of the conical guide wall 91. When the anti-snagging scraper 94 rotates, it scrapes around the surface of the conical guide wall 91 to remove the wet material adhering to the wall and allows the wet material to flow back along the conical guide wall 91 to the wet material outlet 92. The wall-mounted scraping method can reduce the gradual accumulation of wet material on the conical guide wall 91 and help maintain the effective volume of the wet material collection cavity 9 and the discharge channel. The anti-snagging scraper 94 is connected to the inner drive shaft 71 through the reducer 93 located at the center of the wet material collection cavity 9. While the inner drive shaft 71 drives the liquid centrifugal disk 4 to rotate, it transmits power to the reducer 93. After the reducer 93 reduces the output speed, it drives the anti-snagging scraper 94 to rotate slowly. An isolation shell can be set outside the reducer 93 to reduce the entry of wet material into the transmission part. An annular flushing pipe 95 is installed inside the wet material collection chamber 9 and arranged circumferentially along the upper part of the conical guide wall 91. The annular flushing pipe 95 is connected to the liquid feed pipe 3. Part of the liquid transported by the liquid feed pipe 3 enters the annular flushing pipe 95 and is then sprayed onto the conical guide wall 91 by flushing holes 96 distributed circumferentially. The flushing liquid flows downward along the wall surface, which can wet and carry away the wet material that is not completely removed by the anti-stick scraper 94. At the same time, it replenishes and dilutes the wet material, making it easier for the wet material to flow to the wet material outlet 92. The spray direction of the flushing holes 96 is towards the conical guide wall 91 and can be inclined along the wet material discharge direction, so that the flushing liquid has both wall cleaning and downward guiding functions, reducing the probability of local wet material drying and sticking to the wall. By combining conical material guide, low-speed wall scraping, circumferential flushing, and pumping discharge, the adhesion and accumulation of wet material in the collection area can be reduced, making the return conveying process relatively stable.

[0027] The supramolecular oil-free drag-reducing agent preparation and mixing device provided by the present invention forms a liquid curtain and a powder curtain moving in opposite directions through a liquid centrifugal disc 4 and a powder centrifugal disc 6, respectively. This allows the powder to be pre-wetted and initially dispersed before entering the main mixing tank 1. The formed wet material is then transported to below the liquid surface of the main mixing tank 1. Compared with directly pouring the powder from above the liquid surface, this reduces dust dispersion, liquid surface floating, and material splashing during feeding. It also reduces the probability of the powder forming externally wet and internally dry clumps due to rapid surface liquid absorption. Submerged input also allows the premixed wet material to directly enter the flow field inside the tank and continue to disperse under the stirring action, reducing air entrainment and tank wall adhesion, making the powder addition and subsequent mixing process more stable.

[0028] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity. Any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A mixing apparatus for preparing a supramolecular oil-free drag-reducing agent, comprising a main mixing tank (1) equipped with a stirring rack (11), a feeding port (12), and a discharging port (13), characterized in that, It also includes a submerged premixing feeding mechanism (2) connected to the main mixing tank (1), the submerged premixing feeding mechanism (2) comprising: A sealed mixing shell (21) is provided inside, with a central mixing cylinder (22) and a conical hopper (23) located below the central mixing cylinder (22); A liquid centrifugal disc (4) is set inside the central mixing cylinder (22). The liquid feed pipe (3) is connected to the liquid feeder (32) set at the center of the liquid centrifugal disc (4). The outer edge of the liquid centrifugal disc (4) is provided with a downward guide lip (42). The powder centrifugal disc (6) is coaxially arranged below the liquid centrifugal disc (4). The sealed powder silo (5) supplies material to the center of the powder centrifugal disc (6) through the powder conveying pipe (53). The outer edge of the powder centrifugal disc (6) is provided with an upward throwing lip (63). The dual-axis drive assembly includes an outer hollow shaft (7) connected to the liquid centrifugal disc (4), an inner drive shaft (71) connected to the powder centrifugal disc (6), and a liquid disc drive motor (72) and a powder disc drive motor (73) that drive the outer hollow shaft (7) and the inner drive shaft (71) to rotate respectively. The outer hollow shaft (7) is coaxially sleeved on the outer periphery of the inner drive shaft (71). An annular powder-liquid confluence chamber (8) is formed around the two centrifuge discs; The reflux assembly includes a wet material collection chamber (9) formed in a conical collection hopper (23) and a wet material outlet (92), a reflux conveying pipe (97), a reflux conveying pump (98), and a submerged reflux pipe (24) connected in sequence. The submerged reflux pipe (24) extends into the main mixing tank (1) and is provided with a reflux distribution port (25) located below the liquid surface.

2. The apparatus for preparing and mixing supramolecular oil-free drag-reducing agents according to claim 1, characterized in that, The liquid feed pipe (3) is equipped with a feed pump (31), and the liquid feeder (32) includes a central liquid inlet connector (33), a liquid buffer chamber (34), an annular liquid equalization chamber (35), and a liquid guide shroud (37); The liquid feed pipe (3) is connected to the liquid buffer chamber (34) through the central liquid inlet connector (33). The liquid buffer chamber (34) is connected to the annular liquid equalization chamber (35) arranged around its outer periphery. The bottom of the annular liquid equalization chamber (35) is provided with a plurality of liquid equalization holes (36) spaced apart along the circumference and facing the liquid centrifuge plate (4). The liquid guide cover (37) is placed above the central area of ​​the annular liquid equalization chamber (35) and the liquid centrifuge plate (4) to guide the liquid discharged through the liquid equalization holes (36) to the plate surface of the liquid centrifuge plate (4).

3. The apparatus for preparing and mixing supramolecular oil-free drag-reducing agents according to claim 1, characterized in that, The liquid centrifuge disk (4) includes a liquid bearing disk surface (41), a film-forming ring (43), an anti-drip ring (44), and a bottom liquid separator (45). The liquid bearing disk surface (41) is a shallow cone that gradually slopes downward from the center to the outer edge. The downward guide lip (42) is arranged around the outer edge of the liquid bearing disk surface (41) and extends downward. The film-forming ring (43) is circumferentially disposed on the outer periphery of the liquid-bearing disk surface (41) to form an annular liquid film; the anti-drip ring (44) is disposed at the lower end of the downward guide lip (42) to prevent the liquid from flowing back to the bottom of the liquid centrifugal disk (4); The bottom liquid separator (45) is located below the liquid bearing plate (41) and surrounds the outer hollow shaft (7) to isolate the liquid centrifugal disc (4) from the powder centrifugal disc (6).

4. The apparatus for preparing and mixing supramolecular oil-free drag-reducing agents according to claim 1, characterized in that, The sealed powder silo (5) has a sealed feeding port (52) at the top and a conical conveying hopper (51) at the bottom. The discharge end of the conical conveying hopper (51) is connected to the powder conveying pipe (53). The lower end of the powder conveying pipe (53) extends to the central area of ​​the powder centrifugal disc (6), and the annular powder distribution cover (54) is placed on the outside of the lower end of the powder conveying pipe (53) and forms an annular powder distribution channel with the powder centrifugal disc (6). The annular powder distribution channel is equipped with a powder distribution scraper (55) that rotates synchronously with the powder centrifugal disc (6), which is used to spread the powder discharged from the powder conveying pipe (53) along the circumference of the powder centrifugal disc (6).

5. The apparatus for preparing and mixing supramolecular oil-free drag-reducing agents according to claim 1, characterized in that, The powder centrifugal disc (6) includes a powder bearing disc surface (61), radial powder-dispensing blades (62), and a throwing ring (64). The powder bearing disc surface (61) is a shallow cone shape that extends inclinedly from the center to the outer edge. Several radial powder-dispensing blades (62) are arranged at intervals along the circumference of the powder bearing disc surface (61) and extend from its central area to the outer edge. The upward throwing lip (63) is arranged around the outer edge of the powder carrying plate (61) and tilted upward. The throwing ring (64) is arranged on the upper edge of the upward throwing lip (63) so that the powder forms an upward throwing annular powder curtain.

6. The apparatus for preparing and mixing supramolecular oil-free drag-reducing agents according to claim 1, characterized in that, An annular flow guide (81) is provided on the outside of the annular powder-liquid confluence cavity (8). The annular flow guide (81) is arranged around the outside of the liquid centrifugal disk (4) and the powder centrifugal disk (6), and defines the annular powder-liquid confluence cavity (8) between the outer edges of the two centrifugal disks. The inner wall of the annular guide tube (81) is provided with an arc-shaped guide surface (82) that extends obliquely toward the conical hopper (23). The arc-shaped guide surface (82) is provided with an anti-rebound ring (83) to prevent the powder-liquid mixture from rebounding back.

7. The apparatus for preparing and mixing supramolecular oil-free drag-reducing agents according to claim 6, characterized in that, The annular powder-liquid junction cavity (8) is also provided with an annular compensation pipe (84). The annular compensation pipe (84) has several spray holes (85) along the circumference facing the powder-liquid junction area, which are used to supplement the annular powder-liquid junction cavity (8) with sprayed liquid. The annular compensation pipe (84) is connected to the liquid feed pipe (3).

8. The apparatus for preparing and mixing supramolecular oil-free drag-reducing agents according to claim 6, characterized in that, The wet material collection chamber (9) is located below the annular powder-liquid confluence chamber (8), and the inner wall of the wet material collection chamber (9) forms a conical guide wall (91) that gradually narrows toward the wet material outlet (92); The wet material outlet (92) is located at the bottom of the wet material collection chamber (9) and is connected to the return conveying pipe (97). The return conveying pipe (97) is equipped with a return conveying pump (98) for returning the wet material discharged from the wet material collection chamber (9).

9. The apparatus for preparing and mixing supramolecular oil-free drag-reducing agents according to claim 8, characterized in that, The conical guide wall (91) is provided with an anti-snagging scraper (94) that can move along its surface. The anti-snagging scraper (94) is set close to the conical guide wall (91) and can move circumferentially along the surface of the conical guide wall (91) to scrape off the wet material adhering to the conical guide wall (91). The anti-snagging scraper (94) is connected to the inner drive shaft (71) via a speed reducer (93) located at the center of the wet material collection cavity (9), so that the anti-snagging scraper (94) is driven to rotate at low speed by the inner drive shaft (71).

10. The apparatus for preparing and mixing supramolecular oil-free drag-reducing agents according to claim 8, characterized in that, The wet material collection chamber (9) is provided with an annular flushing pipe (95), and the annular flushing pipe (95) is provided with a plurality of flushing holes (96) facing the conical guide wall (91) at intervals along the circumference. The annular flushing pipe (95) is connected to the liquid feed pipe (3).

Images