Microbubble hydrophobic agglomeration-pulse bubble formation coupled microfine particle flotation apparatus and method

Abstract

The present application relates to a kind of micro-vortex hydrophobic agglomeration-pulse bubble formation coupling micro-fine particle flotation equipment and method thereof, including flotation column and micro-vortex device, pipe vortex generator in micro-vortex device and porous plate type pulse bubble generator are independently arranged in the side of flotation column;Pipe vortex generator is equipped with reinforced micro-vortex blade, and medium turbulent intensity micro-vortex is generated, and the collision of fine particle is strengthened by strong entrainment and high doping characteristics, and hydrophobic agglomerate is formed;Porous plate type pulse bubble generator is matched with hydrophobic agglomerate by generating characteristic size bubble, so that it floats and forms concentrate;Micro-vortex device carries out vortex agglomeration flotation to middlings multiple times, and the recovery of micro-fine particle mineral is improved.The present application innovatively applies micro-vortex hydrophobic agglomeration-pulse bubble formation coupling technology under medium turbulent condition, relatively static, and significantly improves the recovery of difficult flotation micro-fine particle mineral, and effectively reduces the amount of reagent, and stably combines hydrophobic aggregate in gas-liquid two-phase flow field.

Description

Technical Field

[0001] This invention relates to the field of fine-particle mineral flotation technology, specifically to a fine-particle flotation device and method coupled with micro-vortex hydrophobic agglomeration and pulse bubble formation. Background Technology

[0002] Fine-grained minerals, characterized by their small mass and large specific surface area, have a low probability of colliding with bubbles, making effective adhesion and separation difficult. Increasing the apparent particle size and reducing the size of flotation bubbles are the main methods to solve the problem of fine-grained flotation. Macromolecular flocculation can effectively increase particle size, but it requires high reagent dosage, has poor selectivity, and is difficult to reuse as recycled water. Under the strong entrainment and high mixing effect of micro-vortices, fine-grained minerals overcome the potential energy barrier through collision and form particle aggregates through hydrophobic attraction, which is a green and efficient method to increase particle size. On the other hand, as the size of the aggregates increases, it is crucial to construct a flotation environment that matches the bubble size and aggregate size. However, conventional flotation bubble-forming methods such as jet cavitation and mechanical stirring rely on liquid phase flow, and the strong turbulence required for bubble formation affects the aggregate size, making it difficult to match the bubble size and the floatability of the aggregates, thus limiting the flotation efficiency. Summary of the Invention

[0003] The purpose of this invention is to solve the above-mentioned problems and provide a micro-vortex hydrophobic agglomeration-pulse bubble formation coupled micro-particle flotation device and method. By controlling the gas-liquid velocity and the blade shape, a local medium-intensity micro-vortex is achieved. The hydrophobic particles are efficiently and stably agglomerated through micro-vortex entrainment and doping. The bubble size is precisely controlled by pulse bubble formation to construct a flotation environment with suitable bubble and agglomerate sizes, thereby achieving efficient flotation enrichment of micro-fine mineral particles.

[0004] The technical solution of the present invention is as follows:

[0005] A micro-vortex hydrophobic agglomeration-pulse bubble formation coupled micro-particle flotation device includes a flotation column and a micro-vortex device. The micro-vortex device includes a porous plate pulse bubble generator for generating bubbles of different sizes and air intake volumes, and a tubular vortex generator for providing vortex agglomeration of fine-particle minerals. When the middlings in the flotation column circulate through the micro-vortex device, they first pass through the tubular vortex generator to generate micro-vortices of moderate turbulence intensity, and then form hydrophobic agglomerates of particles. The hydrophobic agglomerates of particles are mixed with appropriately sized bubbles generated by the porous plate pulse bubble generator and then enter the flotation column.

[0006] Furthermore, the micro-vortex device includes a bubble and agglomerate mixing pipe, a tubular vortex generator, a peristaltic pump, and a tailings liquid circulation pipe. One end of the tailings liquid circulation pipe is connected to the bottom of the flotation column, and the other end of the tailings liquid circulation pipe is connected to one end of the tubular vortex generator via the peristaltic pump. The other end of the tubular vortex generator is connected to the bubble and agglomerate mixing pipe, which is connected to the bottom of the flotation column. The bubble and agglomerate mixing pipe is vertically connected to a porous plate pulse bubble generator.

[0007] Furthermore, the shape and arrangement of the turbulence blades in the tubular vortex generator are as follows: three sets of disks are placed at equal intervals on the central axis of the vortex generating tube, and four sets of parted blades are obliquely embedded at equal intervals in the same direction along the circumference of the disks. The blades are at a certain angle to the central axis: 30°-75°. The parted blades are composed of self-similar rectangles that are repeated in stages, and maintain a similar structure at different scales.

[0008] Furthermore, the porous plate pulse bubble generator includes a porous plate and a pneumatic solenoid valve, and the porous plate pulse bubble generator is disposed on one side of the flotation column; the porous plate is a microporous plate with flexible holes, and the flexible holes can form a flexible opening and closing process with the gas supply.

[0009] Furthermore, the porous plate includes a flexible membrane or rigid sheet with dense micropores.

[0010] A flotation method includes the following steps: Step 1: turn on the air pump to inject gas, the gas pressure range is 3-5 bar, turn on the feed pump to inject the pre-adjusted slurry sample, and the airflow generates bubbles through the micropores of the porous plate.

[0011] Step 2: Maintain a stable apparent velocity for the gas-liquid-solid three-phase flow. The water velocity inside the tubular vortex generator is 5-20 m / s, and the apparent gas velocity is 0.5-2 cm / s, which facilitates the adhesion of particles and bubbles, achieving rapid separation.

[0012] Step 3: The middlings enter the micro vortex device through the circulation port, and the tubular vortex generator enhances the hydrophobic agglomeration effect of the fine-grained minerals to form multi-sized agglomerates in a tiered manner.

[0013] Step 4: Adjust the solenoid valve parameters of the pulse bubble generator to produce bubble sizes that match the floatability of the agglomerates. The bubble flow adheres to and rises with the hydrophobic agglomerates, and multiple cycles are used to achieve efficient recovery of fine particles.

[0014] Advantages of this invention compared to existing microbubble flotation technology for fine-grained mineral particles:

[0015] (1) Unlike strong turbulent flow fields that enhance the collision probability between flotation bubbles and fine particles, moderate turbulence flow fields enhance the aggregation process of hydrophobic fine particles, improve the size stability of aggregates, and couple pulse orifice plate characteristic microbubble generation technology to achieve the recovery of fine mineral particles in a relatively static, low-energy input mode; (2) By using pulse frequency to change the air flow pressure to control the co-optation rate after bubble desorption, the micropore bubble size can be precisely controlled, and the matching degree between bubble size and aggregate floatability can be improved; (3) The self-closing feature of flexible pores under low air pressure conditions hinders fluid seepage, and the pulse airflow drives high-frequency oscillation on the surface of flexible pores to avoid particle deposition and blockage, forming a pulse-based self-cleaning flexible micropore bubble size precise control technology. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a micro-vortex hydrophobic agglomeration-pulse bubble formation coupled microparticle flotation device according to the present invention;

[0017] Figure 2 This is a schematic diagram of the fractal blades of a tubular vortex generator;

[0018] Figure 3 This is a graph showing the cumulative recovery rate of fine-grained molybdenum ore over time at different apparent water velocities.

[0019] In the attached diagram: 1-Feed pump, 2-Liquid flow meter, 3-Overflow trough, 4-Feed pipe, 5-Bubbles and agglomerates mixing pipe, 6-Tube vortex generator, 7-Peristaltic pump, 8-Tailings liquid circulation pipe, 9-Perforated plate, 10-Pneumatic solenoid valve, 11-Concentrate outlet, 12-Level sensor, 13-Flotation column, 14-Tailings outlet solenoid valve, 15-Pressure sensor control box. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "right", "vertical", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this invention, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0022] See appendix Figure 1A micro-vortex hydrophobic agglomeration-pulse bubble generation coupled microparticle flotation device includes a flotation column and a micro-vortex device. The micro-vortex device includes a porous plate pulse bubble generator for generating bubbles of different sizes and air intake rates, and a tubular vortex generator 6 for providing vortex agglomeration of fine mineral particles (attached). Figure 2 When the middlings in the flotation column circulate through the micro-vortex device, they first pass through the tubular vortex generator to generate micro-vortices of moderate turbulence intensity, and then form hydrophobic agglomerates of particles. The hydrophobic agglomerates of particles are mixed with bubbles of appropriate size generated by the porous plate pulse bubble generator and then enter the flotation column.

[0023] The flotation column includes a flotation column body 13, an overflow trough 3, a feeding device, and a control device. The overflow trough 3 is located on the outer circumference of the top of the flotation column 13. The feeding device includes a feed pump 1, a liquid flow meter 2, and a feed pipe 4. The feed pump 1, the liquid flow meter 2, and the feed pipe 4 are connected in sequence. The feed pipe 4 is located at the center of the axis of the flotation column 13.

[0024] The micro-vortex device includes a bubble and agglomerate mixing pipe 5, a tubular vortex generator 6, a peristaltic pump 7, and a tailings liquid circulation pipe 8. One end of the tailings liquid circulation pipe 8 is connected to the bottom of the flotation column 13, and the other end of the tailings liquid circulation pipe 8 is connected to one end of the tubular vortex generator 6 through the peristaltic pump 7. The other end of the tubular vortex generator 6 is connected to the bubble and agglomerate mixing pipe 5. The bubble and agglomerate mixing pipe 5 is connected to the bottom of the flotation column 13, and the bubble and agglomerate mixing pipe 5 is vertically connected to the porous plate pulse bubble generator.

[0025] The porous plate pulse bubble generator includes a porous plate 9 and a pneumatic solenoid valve 10. The porous plate pulse bubble generator 9 is disposed on one side of the flotation column 13. The porous plate 9 is a microporous plate with flexible pores. The microporous plate includes a flexible membrane or rigid sheet with dense micropores. The pulsed airflow drives the surface of the flexible pores to oscillate at high frequency to avoid particle deposition and blockage. The porous plate 9 is connected to the air inlet pipe by threads. When the airflow is input, its pores form microbubbles. The flexible pores open and close in conjunction with the pulsed airflow to prevent pore blockage. The opening size of the porous plate is determined according to the mineral size. At the same time, the pulse parameters of the airflow supply are adjusted to coordinate and control the bubble size, thereby matching the adhering particle aggregates. The pneumatic solenoid valve 10 is used to control the bubble size by adjusting the airflow interruption frequency and time ratio.

[0026] The control device includes a liquid level sensor 12, a pneumatic solenoid valve 10, a tailings outlet solenoid valve 14, and a pressure sensing control box 15. The liquid level sensor 12 is installed inside the flotation column 13. The liquid level sensor 12 is connected to the pressure sensing control box 15. The pressure sensing control box 15 is used to control the pneumatic solenoid valve 10 and the tailings outlet solenoid valve 14.

[0027] The tubular vortex generator 6 includes axisymmetric fractal blades, as shown in the attached figure. Figure 2 The fractal blades are used to enhance the hydrophobic aggregation of fine particles in moderate turbulence and prevent the redispersion of the aggregates. The specifications and arrangement of the fractal blades are as follows: four fractal self-similar rectangular blades are obliquely embedded on the central axis at an angle between 30° and 75°, and are arranged equidistantly on the central axis. The tubular vortex generator has a built-in turbulence-enhancing device that strengthens the microvortex and hydrophobic particle aggregation process through multi-morphological blades under moderate turbulence conditions.

[0028] The tubular vortex generator 6 of this invention is equipped with enhanced micro-vortex blades to generate micro-vortices of moderate turbulence intensity. These micro-vortices, through strong entrainment and high doping characteristics, enhance the collision of fine particles, forming hydrophobic aggregates. A porous plate-type pulse bubble generator then generates bubbles of a specific size, matching the floatability of the hydrophobic aggregates and causing them to float to the surface, forming a concentrate. The micro-vortex device performs multiple vortex flotation processes on the middlings, improving the recovery rate of fine-grained minerals. This invention innovatively applies a micro-vortex hydrophobic agglomeration-pulse bubble coupling technology under moderate turbulence conditions, relatively statically and stably combining hydrophobic aggregates in a gas-liquid two-phase flow field, significantly improving the recovery rate of difficult-to-float fine-grained minerals and effectively reducing reagent consumption.

[0029] This invention synergistically regulates the hydrophobic agglomeration of fine particles and the micropore bubble formation process of pulsed airflow. By enhancing the hydrophobic agglomeration of fine particles through microvortices of moderate turbulence intensity, it avoids the redispersion of agglomerates. At the same time, the wide range of micropore bubble formation sizes of pulsed airflow is adapted to the size characteristics of the aforementioned hydrophobic agglomerates, thus achieving efficient flotation.

[0030] The specific steps of the micro-vortex hydrophobic agglomeration-pulse bubble formation coupling method for the flotation of fine-grained minerals in this invention are as follows:

[0031] Step 1: Turn on the air pump to inject gas. The air pressure range is 3-5 bar. Turn on the feed pump to inject the pre-mixed slurry sample. The airflow generates bubbles through the micropores of the porous plate.

[0032] Step 2: Maintain a stable apparent velocity for the gas-liquid-solid three-phase flow. The water velocity in the tubular vortex generator is 5-20 m / s, and the apparent gas velocity is 0.5-2 cm / s. This facilitates the adhesion of particles and bubbles, enabling rapid separation.

[0033] Step 3: The middlings enter the micro vortex device through the circulation port, and the tubular vortex generator enhances the hydrophobic agglomeration effect of the fine-grained minerals to form multi-sized agglomerates in a tiered manner.

[0034] Step 4: Adjust the solenoid valve parameters of the pulse bubble generator to produce bubble sizes that match the floatability of the agglomerates. The bubble flow adheres to and rises with the hydrophobic agglomerates, and multiple cycles are used to achieve efficient recovery of fine particles.

[0035] Compared with existing technologies, this invention achieves independent and coordinated control of bubble generation and hydrophobic aggregation processes, and can independently adjust energy input and microbubble generation; this invention enhances the hydrophobic aggregation process of fine particles under moderate turbulence flow field conditions, while avoiding redispersion of aggregate structures; this invention uses pulse frequency to change airflow pressure to control the co-optation rate after bubble desorption, achieving precise control of micropore bubble size, and pulsed airflow drives high-frequency oscillation on the flexible pore surface to avoid particle deposition and blockage; this invention achieves stable bubble-aggregate adhesion and reduces redispersion; the wide range of pulsed micropore bubble size in this invention is adapted to the size characteristics of hydrophobic particle aggregation, and has strong universality.

[0036] The following example, using a specific mineral from a mine in Henan Province, further illustrates the micro-vortex hydrophobic agglomeration-pulse bubble formation coupling method for the flotation of fine-grained minerals.

[0037] The mineral used was fine-grained molybdenite, with 80% of the feed particle size below 38 μm and a pulp concentration of 35%. The air flow rate was 1.5 L / min. During the flotation test, deionized water with added frother was mixed with the mineral sample in a certain proportion in the flotation cell for pre-conditioning. After stirring for 2 minutes, the collector was added. Flotation experiments were conducted under three turbulence intensities defined according to the water velocity (2, 10, and 30 m / s) in the tubular vortex generator. The cumulative recovery curves of fine-grained molybdenite under each condition are shown below. Figure 3 As shown. After 10 minutes of flotation, the recovery rate of molybdenum, which is extremely difficult to recover under moderate turbulence conditions, reached 81%, both higher than the 68% in low turbulence and 73% in strong turbulence flotation environments (see attached figure). Figure 3 This indicates that the micro-vortex hydrophobic agglomeration-pulse bubble formation coupled micro-fine particle flotation equipment has a strong ability to recover fine minerals through flotation.

[0038] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A micro-vortex hydrophobic agglomeration-pulse bubble formation coupled microparticle flotation device, characterized in that, The system includes a flotation column and a micro-vortex device. The micro-vortex device comprises a porous plate pulse bubble generator for generating bubbles of different sizes and air intake volumes, and a tubular vortex generator for providing vortex agglomeration of fine-grained minerals. When the middlings in the flotation column circulate through the micro-vortex device, they first pass through the tubular vortex generator to generate micro-vortices of moderate turbulence intensity, forming hydrophobic agglomerates. These hydrophobic agglomerates mix with appropriately sized bubbles generated by the porous plate pulse bubble generator before entering the flotation column. The morphology and arrangement of the turbulence-generating blades within the tubular vortex generator are as follows: [The text abruptly ends here, likely due to an incomplete sentence or missing information.] Three sets of discs are placed at intervals, and four sets of shaped propeller blades are obliquely embedded at equal intervals and in the same direction along the circumference of the discs. The blades are at a certain angle to the central axis: 30°-75°. The shaped propeller blades are composed of self-similar rectangles that repeat in successive stages and maintain a similar structure at different scales. The porous plate pulse bubble generator includes a porous plate and a pneumatic solenoid valve. The porous plate pulse bubble generator is set on one side of the flotation column. The porous plate includes a rigid sheet with dense micropores. The porous plate is a microporous plate with flexible pores. The flexible pores can form a flexible opening and closing process with the gas supply.

2. The micro-vortex hydrophobic agglomeration-pulse bubble formation coupled microparticle flotation device according to claim 1, characterized in that, The micro-vortex device includes a bubble and agglomerate mixing pipe, a tubular vortex generator, a peristaltic pump, and a tailings liquid circulation pipe. One end of the tailings liquid circulation pipe is connected to the bottom of the flotation column, and the other end of the tailings liquid circulation pipe is connected to one end of the tubular vortex generator via the peristaltic pump. The other end of the tubular vortex generator is connected to the bubble and agglomerate mixing pipe, which is connected to the bottom of the flotation column. The bubble and agglomerate mixing pipe is vertically connected to a porous plate pulse bubble generator.

3. A method for a micro-vortex hydrophobic agglomeration-pulse bubble formation coupled microparticle flotation device as described in any one of claims 1-2, characterized in that, Step 1: Turn on the air pump to inject gas at a pressure of 3-5 bar. Turn on the feed pump to inject the pre-treated slurry sample. The airflow generates bubbles through the micropores of the porous plate. Step 2: Maintain a stable apparent velocity for the gas-liquid-solid three-phase flow. The water velocity inside the tubular vortex generator is 5-20 m / s, and the apparent gas velocity is 0.5-2 cm / s. Easily separated particles adhere to the bubbles, achieving rapid separation. Step 3: The middlings enter the micro-vortex device through the circulation port. The tubular vortex generator enhances the hydrophobic agglomeration effect of the fine mineral particles, forming multi-sized agglomerates in a tiered manner. Step 4: Adjust the parameters of the solenoid valve of the pulse bubble generator to generate bubble sizes that match the floatability of the agglomerates. The bubble flow adheres to and rises with the hydrophobic agglomerates. Multiple cycles achieve efficient recovery of fine particles.

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