Improved efficient turbulent flow microbubble flotation device for feeding and discharging materials

Abstract

The invention discloses an improved efficient turbulent flow microbubble flotation device for feeding and discharging materials. Comprising an outer cylinder, an inner cylinder arranged in the outer cylinder, a stirring mechanism arranged in the outer cylinder, a feeding mechanism used for conveying raw materials into the inner cylinder, a concentrate tank located on the upper portion of the outer cylinder, a countercurrent mineralization mechanism arranged in the inner cylinder and a tailing separation mechanism connected to the bottom of the inner cylinder. Through cooperation of the sawtooth disc self-suction dispersion impeller and the false bottom structure, local area circulation can be formed, the elution effect on the surfaces of coarse particles can be enhanced, meanwhile, dispersion of heterogeneous fine silt is facilitated, and the purity of tailings is further ensured; according to the method, the flotation efficiency can be improved, and the energy consumption is greatly reduced; due to the design of the sawtooth disc self-suction dispersion impeller, gas is allowed to enter in a self-suction mode, and energy consumption of traditional air compression equipment is avoided. According to the sawtooth disc self-suction dispersion impeller, suction force brought by the vacuum effect generated by rotation of the impeller can be improved, and suction of more air is promoted.

Description

Technical Field

[0001] The invention relates to the technical field of mineral separation, in particular to an improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials. Background Art

[0002] With the increasing scarcity of global mineral resources and the continuous tightening of environmental protection regulations, traditional mineral processing technology is facing unprecedented challenges. The rapid progress of mechanized mining technology has improved production efficiency, but it has also brought about the problem of increasingly fine mineral particle size. At the same time, the increase in the content of high ash and intergrown minerals in the ore has greatly increased the difficulty of sorting and recycling fine-grained minerals. Especially in the treatment of ultra-fine materials, the effect of traditional flotation technology is not ideal. As the most economical sorting method in the field of mineral processing, froth flotation technology has been widely used in mineral processing plants at home and abroad. The main equipment includes mechanical flotation machines and flotation columns. Although the mechanical agitator flotation machine has a long history, the separation efficiency is obviously insufficient when processing ultra-fine particles with a diameter of less than 45 microns, mainly because the mechanical entrainment phenomenon easily causes the gangue mineral particles to be mistakenly recovered, affecting the grade of the concentrate.

[0003] As an efficient sorting equipment, the flotation column has attracted widespread attention due to its advantages such as simple structure, easy regulation and high flotation efficiency. It is particularly suitable for processing ore resources with low grade, fine embedded particle size and complex mineral composition. In recent years, the application status of new flotation columns such as CPT flotation column, Jameson flotation column, packed flotation column, cyclone-static microbubble flotation column in mineral flotation shows that they have incomparable sorting effects when processing fine and difficult-to-select minerals compared with conventional flotation machines. However, flotation columns also face some challenges in practical applications. Especially when processing highly interlinked minerals, flotation columns often find it difficult to effectively improve the concentrate grade and maintain a high recovery rate. In addition, the shear desorption phenomenon of coarse particles under high turbulence limits the sorting efficiency of coarse particles, and the selectivity and adaptability need to be improved urgently.

[0004] In order to meet these challenges, the industry has an increasingly urgent need to develop new flotation equipment, with the goal of improving the recovery rate and sorting efficiency of fine-grained minerals while reducing energy consumption and environmental impact. Against this background, two-stage flotation equipment came into being to specifically solve the problems of low recovery rate and poor selectivity in fine-grained sorting. This technology not only optimizes the mineral sorting process and improves energy utilization efficiency, but also enhances the overall economy and sustainability of the flotation system, bringing innovation to the mineral processing industry. However, the existing two-stage flotation machine, as described in patent CN117983421A, uses the method of collecting tailings at the bottom of the outer cylinder, which is easily affected by liquid level fluctuations. The slurry accumulates in the stirring area of ​​the inner cylinder when the machine is shut down, resulting in mineral deposition and affecting the normal startup of the equipment. Furthermore, the flat bottom structure of the outer cylinder combined with the anti-rotation plate can easily lead to insufficient slurry rising power and difficulty in foam overflow.

[0005] Therefore, it is necessary to further improve the existing technology to provide a more reliable flotation solution. Summary of the invention

[0006] In view of the above analysis, the present invention aims to provide an improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials, so as to solve the problems of high power consumption, coarse particle run-off, low probability of fine particle collision and high product ash content existing in the existing fine particle flotation equipment.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: to provide an improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials, comprising: an outer cylinder, an inner cylinder arranged inside the outer cylinder, a stirring mechanism arranged inside the outer cylinder, a feeding mechanism for conveying raw materials into the inner cylinder, a concentrate tank located at the upper part of the outer cylinder, a countercurrent mineralization mechanism arranged inside the inner cylinder, and a tailings separation mechanism connected to the bottom of the inner cylinder;

[0008] The countercurrent mineralization mechanism comprises a perforated plate type tangential flow impeller, a high-throughput axial conveying impeller and a sawtooth disc self-priming dispersion impeller which are concentrically arranged on the stirring shaft of the stirring mechanism and are sequentially spaced from top to bottom.

[0009] Preferably, the feeding mechanism includes an annular distribution pipe arranged around the middle of the outer cylinder and a plurality of feeding pipes connected to the annular distribution pipe, the ends of the feeding pipes are perpendicular to the top of the inner cylinder, and a feeding port is opened on the annular distribution pipe.

[0010] Preferably, a conical partition is sealed between the outer cylinder and the inner cylinder, and the area between the conical partition and the inner cylinder forms a conical flow guide cavity that is recessed downward.

[0011] Preferably, a plurality of anti-rotation grooves for the slurry in the inner cylinder to pass through are arranged in an annular manner on the outer wall of the upper portion of the inner cylinder between the cover plate and the conical partition plate, and the anti-rotation grooves are inclined rectangular grooves.

[0012] Preferably, a cover plate is provided on the upper part of the inner cylinder in a sealed manner, and a tube hole for inserting the feeding tube and a shaft hole for inserting the stirring shaft are provided on the cover plate;

[0013] The stirring mechanism comprises a stirring motor disposed above the outer cylinder and a stirring shaft drivingly connected to the stirring motor;

[0014] A support plate for mounting a stirring motor is disposed above the outer cylinder, and an air duct communicating with the external environment is disposed below the stirring motor on the support plate;

[0015] The stirring shaft is a hollow shaft. The upper part and the lower part of the stirring shaft are respectively provided with an upper air inlet hole and a lower air inlet hole. The upper air inlet hole is connected with an air inlet ring, and the air inlet ring is located in the air duct.

[0016] Preferably, the sawtooth disc self-priming dispersion impeller comprises an upper sawtooth disc, a dispersion impeller with a tubular structure and a lower sawtooth disc which are sequentially connected from top to bottom;

[0017] The dispersing impeller comprises a plurality of impeller blades connected to the stirring shaft at annular intervals, the interior of the impeller blades has a hollow tube cavity structure, the hollow tube cavity structure forms a suction port and a discharge port at the inner end and the outer end of the impeller blade respectively, and a circulation cavity is formed between two adjacent impellers, the discharge port is connected to the lower air inlet hole on the stirring shaft through the circulation cavity at a corresponding position, and the bottom of the internal cavity of the stirring shaft does not penetrate the lower serrated disc;

[0018] The upper sawtooth disc has a sawtooth portion at its edge, and a plurality of upper disc holes are opened through the middle portion; the lower sawtooth disc has a sawtooth portion at its edge, and a plurality of lower disc holes are opened through the middle portion; when viewed in the vertical direction, the upper disc holes and the lower disc holes do not completely overlap;

[0019] The impeller blades do not completely cover or partially cover the upper disc hole or the lower disc hole, so that the upper disc hole and the lower disc hole can be connected up and down through the circulation cavity between adjacent impeller blades.

[0020] Preferably, the orifice plate type tangential flow impeller comprises a plurality of trapezoidal blades annularly connected to the stirring shaft, and a plurality of through holes are arranged in an array on the trapezoidal blades;

[0021] The high-throughput axial transport impeller comprises a plurality of lifting impellers annularly connected to the stirring shaft, wherein the lifting impeller comprises an impeller connecting rod connected to the stirring shaft and an arc-shaped impeller plate connected to the end of the impeller connecting rod;

[0022] The arc-shaped impeller plate is tilted, with its lower surface concave inwards and its upper surface convex outwards. The connection position between the impeller connecting rod and the arc-shaped impeller plate is above the center line of the arc-shaped impeller plate.

[0023] Preferably, a false bottom is provided at the bottom of the inner cylinder and is located between the serrated disc self-priming dispersion impeller and the tailings separation mechanism. The false bottom includes a plurality of support columns connected to the bottom of the inner cylinder, a bottom plate connected above the support columns, and a slurry hole opened in the middle of the bottom plate. A gap is left between the bottom plate and the lower serrated disc, and the through hole is concentric with the stirring shaft and is located below the lower serrated disc.

[0024] Preferably, the tailings separation mechanism comprises a concentrating cone disposed in communication with the bottom of the inner tube and below the false bottom, a tailings pipe communicating with the concentrating cone, and a tailings valve disposed on the tailings pipe.

[0025] Preferably, a variable diameter cover is arranged above the inner part of the outer cylinder, the variable diameter cover comprises a conical cover body part connected to the inner wall of the outer cylinder and a cylindrical cover body part connected above the conical cover body part, and a concentrate groove is formed between the variable diameter cover and the inner wall of the outer cylinder;

[0026] A water distribution ring and a spray water pipe connected to the water distribution ring are arranged on the inner wall of the outer cylinder in the area above the concentrate tank, and a water spray port is opened on the water distribution ring.

[0027] Another aspect of the present invention is to provide a novel method for enhancing the turbulent microbubble flotation process, using the above device to enhance the flotation of minerals. The key to this method is that by combining countercurrent mineralization with cyclone flow, the contact conditions between minerals and bubbles are significantly improved, and the flotation efficiency is improved, especially in the separation of fine particles and coarse particles.

[0028] The beneficial effects of the present invention are:

[0029] 1. In the improved high-efficiency turbulent microbubble flotation device for feeding and discharging provided by the present invention, the cooperation of the sawtooth disc self-priming dispersion impeller and the false bottom structure can form a local area circulation, which can enhance the elution effect of the coarse particle surface, and at the same time help to disperse the heterogeneous fine mud, further ensuring the purity of the tailings;

[0030] The sawtooth disc self-priming dispersion impeller of the present invention can improve the suction force brought by the vacuum effect generated by the rotation of the impeller, promote the inhalation of more air; and can also promote the formation of finer microbubbles of the incoming air, thereby improving the mineralization effect;

[0031] 2. In addition to improving flotation efficiency, the present invention also significantly reduces energy consumption; the design of the serrated disc self-priming dispersion impeller allows gas to enter by self-priming, avoiding the energy consumption of traditional compressed air equipment. At the same time, the three impellers in the countercurrent mineralization mechanism (serrated disc self-priming dispersion impeller, high-throughput axial conveying impeller, and orifice-type tangential flow impeller) are arranged in an inverted cone with a diameter that gradually increases from bottom to top, reducing shaft resistance and thus reducing energy input; when energy is only input into a smaller collision reaction zone, the overall energy consumption and operating costs are significantly reduced, bringing better economic benefits.

[0032] 3. The present invention realizes high turbulence mineralization and low turbulence static separation of fine materials by introducing a perforated plate type tangential flow impeller. This design greatly improves the recovery rate and selectivity of fine-grained minerals.

[0033] 4. The present invention effectively shortens the migration path of mineralized bubbles through the countercurrent mineralization mechanism, and the formation of upwelling helps the unpowered transportation of foam. This design not only improves the processing capacity of the equipment, but also makes the flotation process more efficient.

[0034] 5. The tailings outlet of the present invention is arranged at the bottom of the inner tube, which is convenient for liquid level control and avoids operation problems caused by mineral accumulation when the equipment is shut down, thereby improving the reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the internal structure of the improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials in Example 1 of the present invention;

[0036] Figure 2 This is a schematic diagram of the external structure of the improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials in Example 1 of the present invention;

[0037] Figure 3 This is a schematic diagram of the internal model structure of the improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials in Example 1 of the present invention;

[0038] Figure 4 This is a schematic diagram of the structure of the countercurrent mineralization mechanism in Example 1 of the present invention;

[0039] Figure 5 This is a schematic diagram of the model structure of the countercurrent mineralization mechanism in Example 1 of the present invention;

[0040] Figure 6 It is a partial cross-sectional structural schematic diagram of the sawtooth disc self-priming dispersion impeller in Example 1 of the present invention;

[0041] Figure 7 A model diagram of a partial cross-sectional structure of a sawtooth disc self-priming dispersion impeller in Example 1 of the present invention;

[0042] Figure 8 It is a schematic diagram of the slurry flow state inside the improved high-efficiency turbulent microbubble flotation device for feeding and discharging in Example 1 of the present invention;

[0043] Fig. 9 The yield and ash content of clean coal and tail coal of three flotation equipments CFM, TJW and XFD in the test example of the present invention;

[0044] Fig.10 It is the recovery rate index of the three flotation devices CFM, TJW and XFD in the test example of the present invention.

[0045] Description of reference numerals:

[0046] 1—outer cylinder; 11—conical partition; 12—conical flow guide cavity; 13—support plate; 14—air duct; 15—diameter-changing cover; 151—conical cover body; 152—columnar cover body; 16—spray water pipe; 17—water distribution ring; 18—water spray port;

[0047] 2—inner cylinder; 21—rotation-stopping groove; 22—cover plate; 23—false bottom; 231—support column; 232—bottom plate; 233—slurry hole;

[0048] 3—stirring mechanism; 31—stirring motor; 32—stirring shaft; 33—upper air inlet; 34—lower air inlet; 35—inlet ring;

[0049] 4—feeding mechanism; 41—annular distribution pipe; 42—feeding pipe; 43—feeding port;

[0050] 5—concentrate tank; 51—concentrate port;

[0051] 6—Countercurrent mineralization mechanism;

[0052] 61—orifice plate type tangential flow impeller; 611—trapezoidal blades; 612—through holes;

[0053] 62—high-throughput axial conveying impeller; 621—lifting impeller; 622—impeller connecting rod; 623—arc-shaped impeller plate;

[0054] 63—serrated disc self-priming dispersion impeller; 631—upper serrated disc; 632—dispersion impeller; 633—lower serrated disc; 6321—impeller blade; 6322—hollow tube cavity structure; 6323—intake port; 6324—discharge port; 6325—circulation cavity; 634—serrated portion; 635—upper disc hole; 636—lower disc hole;

[0055] 7—tailings separation mechanism; 71—concentration cone; 72—tailings pipe; 73—tailings valve; 74—tailings outlet. DETAILED DESCRIPTION

[0056] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0057] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0058] Example 1

[0059] Reference Figure 1-8The present embodiment provides an improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials, comprising: an outer cylinder 1, an inner cylinder 2 arranged inside the outer cylinder 1, a stirring mechanism 3 arranged inside the outer cylinder 1, a feeding mechanism 4 for conveying raw materials into the inner cylinder 2, a concentrate tank 5 located at the upper part of the outer cylinder 1, a countercurrent mineralization mechanism 6 arranged inside the inner cylinder 2, and a tailings separation mechanism 7 connected to the bottom of the inner cylinder 2.

[0060] The countercurrent mineralization mechanism 6 comprises a perforated plate type tangential flow impeller 61, a high-throughput axial conveying impeller 62 and a sawtooth disc self-priming dispersion impeller 63 which are coaxially arranged on the stirring shaft 32 of the stirring mechanism 3 and are sequentially spaced from top to bottom.

[0061] In this embodiment, the feeding mechanism 4 includes an annular distribution pipe 41 arranged around the middle of the outer cylinder 1 and a plurality of feeding pipes 42 (8 groups of feeding pipes 42 in this embodiment) connected to the annular distribution pipe 41. The ends of the feeding pipes 42 are perpendicular to the top of the inner cylinder 2, and a feeding port 43 is opened on the annular distribution pipe 41.

[0062] Among them, vertical feeding includes the following advantages:

[0063] (1) Able to form a stable liquid flow: Vertical feeding can ensure that the slurry enters the flotation tank in a stable and concentrated manner, which helps to form a stable liquid flow, thereby improving the efficiency and stability of the flotation process. (2) Improve mineralization efficiency: Vertical feeding helps the slurry and microbubbles to be fully mixed in the impeller blades, increasing the collision opportunities between ore particles and bubbles, thereby increasing the probability of bubble mineralization. (3) Improve sorting efficiency: Vertical feeding combined with the rotation of the impeller can reduce energy consumption because the impeller has a smaller diameter and a lower circumferential speed, thereby reducing the power consumption of the equipment.

[0064] In this embodiment, a conical partition plate 11 is sealed between the outer cylinder 1 and the inner cylinder 2 , and the area between the conical partition plate 11 and the inner cylinder 2 forms a conical flow guide cavity 12 that is concave downward.

[0065] In this embodiment, a plurality of anti-rotation grooves 21 are arranged in an annular pattern on the outer wall of the upper portion of the inner cylinder 2 between the cover plate 22 and the conical partition plate 11 for the slurry in the inner cylinder 2 to pass through. The anti-rotation grooves 21 are inclined rectangular grooves.

[0066] In this embodiment, the upper part of the inner cylinder 2 is sealed with a cover plate 22, and the cover plate 22 is provided with a tube hole for inserting the feed pipe 42 and a shaft hole for inserting the stirring shaft;

[0067] The stirring mechanism 3 includes a stirring motor 31 disposed above the outer cylinder 1 and a stirring shaft 32 drivingly connected to the stirring motor 31;

[0068] A support plate 13 for mounting a stirring motor 31 is disposed above the outer cylinder 1, and an air duct 14 communicating with the external environment is disposed below the stirring motor 31 on the support plate 13;

[0069] The stirring shaft 32 is a hollow shaft, and an upper air inlet hole 33 and a lower air inlet hole 34 are respectively provided at the upper and lower parts of the stirring shaft 32. An air inlet ring 35 is provided in a connecting sleeve on the upper air inlet hole 33, and the air inlet ring 35 is located in the air duct 14. When the stirring shaft 32 rotates, the external air first enters the air duct 14, and then enters the cavity inside the stirring shaft 32 through the air inlet ring 35, and then is dispersed into the slurry in the inner cylinder 2 by the sawtooth disc self-priming dispersion impeller 63.

[0070] In this embodiment, the sawtooth disc self-priming dispersion impeller 63 includes an upper sawtooth disc 631, a dispersion impeller 632 with a tubular structure, and a lower sawtooth disc 633 which are sequentially connected from top to bottom;

[0071] The dispersion impeller 632 includes a plurality of impeller blades 6321 (six in this embodiment) connected to the stirring shaft 32 at annular intervals. The impeller blades 6321 have a hollow tube cavity structure 6322 inside. The hollow tube cavity structure 6322 forms a suction port 6323 and a discharge port 6324 at the inner and outer ends of the impeller blades 6321, respectively. A circulation cavity 6325 is formed between two adjacent impellers. The discharge port 6324 is connected to the lower air inlet hole 34 on the stirring shaft 32 through the circulation cavity 6325 at the corresponding position. The bottom of the internal cavity of the stirring shaft 32 does not penetrate the lower serrated disc 633.

[0072] The upper sawtooth disc 631 has a sawtooth portion 634 at its edge, and a plurality of upper disc holes 635 are opened through the middle part; the lower sawtooth disc 633 has a sawtooth portion 634 at its edge, and a plurality of lower disc holes 636 are opened through the middle part; when viewed in the vertical direction, the upper disc holes 635 and the lower disc holes 636 do not completely overlap;

[0073] The impeller blades 6321 do not completely cover or partially cover the upper disc hole 635 or the lower disc hole 636 , so that the upper disc hole 635 and the lower disc hole 636 can be connected up and down through the circulation cavity 6325 between adjacent impeller blades 6321 .

[0074] In this embodiment, the orifice plate type tangential flow impeller 61 includes a plurality of trapezoidal blades 611 (six in this embodiment) annularly connected to the stirring shaft 32, and a plurality of through holes 612 are arranged in an array on the trapezoidal blades 611. When the orifice plate type tangential flow impeller 61 rotates, it can scrub the mineral particles and promote the mineralization of the particles.

[0075] The high-throughput axial conveying impeller 62 includes a plurality of lifting impellers 621 (six in this embodiment) connected in an annular manner to the stirring shaft 32. The lifting impeller 621 includes an impeller connecting rod 622 connected to the stirring shaft 32 and an arc-shaped impeller plate 623 connected to the end of the impeller connecting rod 622. The arc-shaped impeller plate 623 is tilted, with its lower surface concave inward and its upper surface convex outward. The connection position between the impeller connecting rod 622 and the arc-shaped impeller plate 623 is above the center line of the arc-shaped impeller plate 623. When the high-throughput axial conveying impeller 62 rotates, it can produce an upward lifting effect on the slurry, thereby promoting the sorting process.

[0076] Among them, the diameters of the impeller blade 6321, the trapezoidal blade 611, and the lifting impeller 621 increase successively to form an inverted cone arrangement, which can reduce shaft resistance and thus reduce the energy input of the rotating shaft.

[0077] In this embodiment, a false bottom 23 is provided at the bottom of the inner cylinder 2 and is located between the serrated disc self-priming dispersion impeller 63 and the tailings separation mechanism 7. The false bottom 23 includes a plurality of support columns 231 connected to the bottom of the inner cylinder 2, a bottom plate 232 connected above the support columns 231, and a slurry hole 233 opened in the middle of the bottom plate 232. A gap is left between the bottom plate 232 and the lower serrated disc 633. The through hole 612 is concentric with the stirring shaft 32 and is located below the lower serrated disc 633.

[0078] In this embodiment, the tailings separation mechanism 7 includes a concentrating cone 71 connected to the bottom of the inner tube 2 and below the false bottom 23, a tailings pipe 72 connected to the concentrating cone 71, and a tailings valve 73 arranged on the tailings pipe 72. The end of the tailings pipe 72 forms a tailings port 74.

[0079] In this embodiment, a variable diameter cover 15 is arranged above the inner part of the outer cylinder 1. The variable diameter cover 15 includes a conical cover body portion 151 connected to the inner wall of the outer cylinder 1 and a cylindrical cover body portion 152 connected above the conical cover body portion 151. A concentrate groove 5 is formed between the variable diameter cover 15 and the inner wall of the outer cylinder 1. A concentrate port 51 is arranged on the concentrate groove 5.

[0080] A water distribution ring 17 and a spray water pipe 16 connected to the water distribution ring 17 are provided on the inner wall of the outer cylinder 1 above the concentrate tank 5 , and a water spray port 18 is provided on the water distribution ring 17 .

[0081] The outer cylinder 1 of the device sequentially forms a foam separation zone, a static separation zone, a countercurrent mineralization zone and a tailings separation zone from top to bottom. Specifically, a foam separation zone is formed in the concentrate tank 5, a static separation zone is formed in the area between the conical partition 11 and the concentrate tank 5, a countercurrent mineralization zone is formed in the inner cylinder 2, and a tailings separation zone is formed in the tailings separation mechanism 7.

[0082] The overall working principle and process of the flotation device of this embodiment are as follows:

[0083] 1. The slurry after slurry adjustment is sent to the feed port 43 through the slurry pump, and the annular distribution pipe 41 evenly distributes the slurry to the 8 connected groups of downward feeding feed pipes 42. At this time, the stirring motor 31 drives the stirring shaft 32 to rotate, and the middle layer (circulation chamber 6325 area) of the sawtooth disk self-priming dispersion impeller 63 forms a negative pressure, and the air is sucked into the air intake ring 35 through the air duct 14, and enters the countercurrent mineralization area inside the inner tube 2 through the upper air intake hole 33 and the lower air intake hole 34 in turn; the air is restricted and dispersed through the air holes, and is cut by the sawtooth disk to form microbubbles, which makes it easier to promote the collision of fine particles and bubbles.

[0084] 2. The microbubbles are lifted by the high-throughput axial conveying impeller 62 to the middle and upper part of the countercurrent mineralization zone, and meet the slurry fed through the feed pipe 42 at the orifice plate type tangential flow impeller 61. The particles are scrubbed by the orifice plate type tangential flow impeller 61 and mineralized with the microbubbles; the fine particles are transported to the anti-rotation groove 21 by the high-throughput axial conveying impeller 62 due to their strong water-carrying ability and then enter the static separation zone, while the coarser particles will sink over the high-throughput axial conveying impeller 62 and enter under the serrated disc self-priming dispersion impeller 63.

[0085] 3. The false bottom 23 cooperates with the sawtooth disc self-priming dispersion blades to form a local circulation, capture and float the particles that are not countercurrently mineralized, and the tailings particles settle into the concentration cone 71 at the bottom of the countercurrent mineralization area. The concentration cone 71 can effectively promote the sedimentation of particles and reduce the impact of tailings discharge on the overall slurry level. After the tailings are concentrated, they are discharged through the tailings valve 73 and the tailings port 74.

[0086] 4. The conical partition 11 (with a conical guide cavity 12 formed on the top) cooperates with the interior of the concentrate tank 5 to form a C-shaped structure (refer to Figure 8 ), after the mineralized bubbles hit the C-shaped structure, a guide is formed, which promotes the formation of a C-shaped flow direction, which can provide upward power for the mineralized bubbles, and also promote the foam to form a concentrate product outward, reduce the existence of dead zones, and push the mineralized gas flocs to rise to the foam separation zone, and finally overflow into the concentrate tank 5, and then enter the concentrate port 51 for discharge after the overflow is sprayed with water through the water spray port 18 for defoaming.

[0087] In this embodiment, the sawtooth disc self-priming dispersion impeller 63 can play the following roles:

[0088] (1) Improving the suction force brought by the vacuum effect generated by the rotation of the impeller, and promoting the inhalation of more air: When the sawtooth disc self-priming dispersion impeller 63 rotates at a high speed, the impeller blade 6321 with the hollow tube structure 6322 inside can quickly and massively throw the internal air outward in the direction of rotation, and a negative pressure area will be formed in the circulation cavity 6325, so that the external air is sucked in through the cavity in the stirring shaft 32 and enters the slurry; at the same time, during the rotation process, the impeller blade 6321 can also play a stirring role on the slurry, which can enhance the collision between the bubbles and the slurry;

[0089] (2) Promote the incoming air to form finer microbubbles, thereby enhancing the mineralization effect:

[0090] When the sawtooth disc self-priming dispersion impeller 63 rotates at a high speed, the sawtooth portions 634 at the edges of the upper sawtooth disc 631 and the lower sawtooth disc 633 can provide additional shearing action, so that the inhaled air is sheared into smaller microbubbles. The formation of a large number of microbubbles is beneficial to enhance the mineralization effect.

[0091] (3) Cooperate with the false bottom 23 to form a local slurry circulation and improve the mineralization rate of particles:

[0092] Reference Figure 5 , Figure 7 , Figure 8 Under the effect of the negative pressure (circulation chamber 6325 area) generated by the impeller blades 6321 of the hollow tubular structure 6322, and the cooperation of the fine gap formed by the lower serrated disk 633 and the false bottom 23, the slurry can be sucked from the center of the false bottom 23 through the lower disk hole 636 into the circulation chamber 6325 area between the impeller blades 6321. During this process, the slurry above the upper serrated disk 631 will also be sucked into the circulation chamber 6325 area through the upper disk hole 635, and then thrown out together along the rotation direction. During the throwing process, it can collide with the generated microbubbles. The slurry and the bubbles are thrown out and hit the wall of the inner tube 2. After that, with the auxiliary lifting of the high-throughput axial conveying impeller 62, the mineralized particles rise, and the unmineralized particles fall along the wall to the lower edge of the false bottom 23. This process is repeated, and the tailings particles are accumulated and discharged at the edge of the concentration cone 71, while the mineralizable particles continue to be sucked into circulation from the center of the false bottom 23.

[0093] It should be noted that, according to the nature of the feed and the needs of the production site, the number of trapezoidal blades 611 of the orifice-type tangential flow impeller 61 can be adjusted to control the shearing effect on the slurry. When the mineral particles are complex and the fine mud content is high (difficult to float), the number of trapezoidal blades 611 can be increased to enhance the scrubbing effect; when the mineral particles are relatively uniform and the fine mud content is low (easy to float), the number of trapezoidal blades 611 can be reduced to increase the throughput of the slurry, thereby increasing the processing capacity of the equipment. At the same time, the foam height can be controlled by adjusting the opening of the tailings valve 73, thereby adjusting the quality and yield of the concentrate.

[0094] Test Case

[0095] In order to further illustrate the present invention, the following flotation experiment is carried out using the improved high-efficiency turbulent microbubble flotation device (with a volume of 3L, denoted as CFM) for feeding and discharging of Example 1, and a conventional laboratory flotation machine (XFD-3L, denoted as XFD) and a turbulent static microbubble flotation machine (denoted as TJW) with the same structure as Example 1 of CN117983421A are used as comparisons. The same flotation process parameters are adopted and the raw coal of Wobei Coal Preparation Plant is used as the flotation feed for the experiment.

[0096] The flotation process parameters are as follows: the collector and frother are original diesel and No. 2 oil, respectively, with dosages of 500g / t and 100g / t; the flotation feed concentration is maintained at 100g / L, and the flotation time is 3min.

[0097] The particle size composition of flotation feed is shown in Table 1:

[0098] Table 1 Flotation feed particle size composition

[0099]

[0100] Particle size composition analysis: The dominant particle size of flotation feed is -0.045mm, accounting for 48.33% of the total sample yield, with an ash content of 36.42%. The fine particle content is high, which is prone to fine mud cover and entrainment, which is not conducive to conventional flotation separation. The slime content and ash content of each particle size are unevenly distributed. The ash content of the slime increases with the decrease of particle size, and the overall ash content is high. The +0.25mm particle size has a small amount of slime, with an ash content of 9.14%, but this part of low-ash slime is easy to desorb during the flotation separation process, and runs coarsely to the flotation tail coal product, which cannot be effectively recovered, resulting in low tail coal ash content.

[0101] The yield and ash content of clean coal and tail coal of three flotation equipments CFM, TJW and XFD are as follows: Fig.10 As shown in the figure, CFM clean and CFM tail represent the clean coal and tail coal obtained by CFM flotation, TJW clean and TJW tail represent the clean coal and tail coal obtained by TJW flotation, and XFD clean and XFD tail represent the clean coal and tail coal obtained by XFD flotation. The flotation recovery index results of the three flotation equipment are shown in Fig.10 From the flotation results, it can be seen that CFM has the best effect, the highest tailing ash content, and the flotation kinetics of CFM is faster, which is conducive to reducing the size of the equipment.

[0102] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.

Claims

1. An improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials, characterized in that: include: An outer cylinder, an inner cylinder arranged inside the outer cylinder, a stirring mechanism arranged inside the outer cylinder, a feeding mechanism for conveying raw materials into the inner cylinder, a concentrate tank located at the upper part of the outer cylinder, a countercurrent mineralization mechanism arranged inside the inner cylinder, and a tailings separation mechanism connected to the bottom of the inner cylinder; The countercurrent mineralization mechanism comprises a perforated plate type tangential flow impeller, a high-throughput axial conveying impeller and a sawtooth disc self-priming dispersion impeller which are concentrically arranged on the stirring shaft of the stirring mechanism and are sequentially spaced from top to bottom.

2. The improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials according to claim 1 is characterized in that: The feeding mechanism includes an annular distribution pipe arranged around the middle of the outer tube and a plurality of feeding pipes connected to the annular distribution pipe. The ends of the feeding pipes are perpendicular to the top of the inner tube. The annular distribution pipe is provided with a feeding port.

3. The improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials according to claim 2 is characterized in that: A conical partition is sealed between the outer cylinder and the inner cylinder, and a conical flow guide cavity recessed downward is formed in the area between the conical partition and the inner cylinder.

4. The improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials according to claim 3 is characterized in that: A plurality of anti-rotation grooves for the slurry in the inner cylinder to pass through are arranged in an annular array on the outer wall of the upper part of the inner cylinder between the cover plate and the conical partition plate. The anti-rotation grooves are inclined rectangular grooves.

5. The improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials according to claim 4 is characterized in that: The upper part of the inner cylinder is sealed with a cover plate, and the cover plate is provided with a tube hole for inserting the feeding tube and a shaft hole for inserting the stirring shaft; The stirring mechanism comprises a stirring motor disposed above the outer cylinder and a stirring shaft drivingly connected to the stirring motor; A support plate for mounting a stirring motor is disposed above the outer cylinder, and an air duct communicating with the external environment is disposed below the stirring motor on the support plate; The stirring shaft is a hollow shaft. The upper part and the lower part of the stirring shaft are respectively provided with an upper air inlet hole and a lower air inlet hole. The upper air inlet hole is connected with an air inlet ring, and the air inlet ring is located in the air duct.

6. The improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials according to claim 5 is characterized in that: The sawtooth disc self-priming dispersion impeller comprises an upper sawtooth disc, a dispersion impeller with a tubular structure and a lower sawtooth disc which are sequentially connected from top to bottom; The dispersing impeller comprises a plurality of impeller blades connected to the stirring shaft at annular intervals, the interior of the impeller blades has a hollow tube cavity structure, the hollow tube cavity structure forms a suction port and a discharge port at the inner end and the outer end of the impeller blade respectively, and a circulation cavity is formed between two adjacent impellers, the discharge port is connected to the lower air inlet hole on the stirring shaft through the circulation cavity at a corresponding position, and the bottom of the internal cavity of the stirring shaft does not penetrate the lower serrated disc; The upper sawtooth disc has a sawtooth portion at its edge, and a plurality of upper disc holes are opened through the middle portion; the lower sawtooth disc has a sawtooth portion at its edge, and a plurality of lower disc holes are opened through the middle portion; when viewed in the vertical direction, the upper disc holes and the lower disc holes do not completely overlap; The impeller blades do not completely cover or partially cover the upper disc hole or the lower disc hole, so that the upper disc hole and the lower disc hole can be connected up and down through the circulation cavity between adjacent impeller blades.

7. The improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials according to claim 1 is characterized in that: The orifice plate type tangential flow impeller comprises a plurality of trapezoidal blades annularly connected to the stirring shaft, and a plurality of through holes are arranged in an array on the trapezoidal blades; The high-throughput axial transport impeller comprises a plurality of lifting impellers annularly connected to the stirring shaft, wherein the lifting impeller comprises an impeller connecting rod connected to the stirring shaft and an arc-shaped impeller plate connected to the end of the impeller connecting rod; The arc-shaped impeller plate is tilted, with its lower surface concave inwards and its upper surface convex outwards. The connection position between the impeller connecting rod and the arc-shaped impeller plate is above the center line of the arc-shaped impeller plate.

8. The improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials according to claim 7 is characterized in that: A false bottom is provided at the bottom of the inner cylinder and is located between the serrated disc self-priming dispersion impeller and the tailings separation mechanism. The false bottom includes a plurality of support columns connected to the bottom of the inner cylinder, a bottom plate connected above the support columns, and a slurry hole opened in the middle of the bottom plate. A gap is left between the bottom plate and the lower serrated disc. The through hole is concentric with the stirring shaft and is located below the lower serrated disc.

9. The improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials according to claim 8, characterized in that: The tailings separation mechanism comprises a concentrating cone which is arranged in communication with the bottom of the inner cylinder and below the false bottom, a tailings pipe which is in communication with the concentrating cone, and a tailings valve arranged on the tailings pipe.

10. The improved high-efficiency turbulent microbubble flotation device for feeding and discharging materials according to claim 1, characterized in that: A variable diameter cover is arranged above the inner part of the outer cylinder, the variable diameter cover comprises a conical cover body part connected to the inner wall of the outer cylinder and a cylindrical cover body part connected above the conical cover body part, and a concentrate groove is formed between the variable diameter cover and the inner wall of the outer cylinder; A water distribution ring and a spray water pipe connected to the water distribution ring are arranged on the inner wall of the outer cylinder in the area above the concentrate tank, and a water spray port is opened on the water distribution ring.

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