Fluidized reverse screening apparatus and method for fine particle classification

Abstract

The application provides a fluidized reverse screening device and method for fine particle classification, which comprises a screening tank, a ventilation plate and a screening unit. The screening tank is provided with a discharge port at the top. The ventilation plate is located at the bottom of the inner cavity of the screening tank. The inner cavity of the screening tank is divided into an upper screening chamber and a hot air chamber by the ventilation plate. The screening tank is provided with a hot air duct connected to the hot air chamber to supply hot air to the hot air chamber. The hot air is blown to the screening chamber through the ventilation holes of the ventilation plate. The screening unit comprises a screen plate, an annular sealing plate and a vibrating ball. The screen plate is inclinedly arranged in the screening chamber. The edge of the screen plate is provided with an elastic band, and the elastic band is connected to the screening tank. The annular sealing plate is located on the upper inclined surface of the screen plate. A slide is formed between the annular sealing plate, the screening tank and the screen plate. When the particles are suspended by the hot air flow, the particles can be continuously dried, so as to avoid the aggregation of the particles, improve the screening effect, reduce the probability of clogging the screen holes and accelerate the screening efficiency.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of mineral particle screening, and particularly relates to a fluidized reverse screening device and method for micro-fine particle classification. BACKGROUND

[0002] Particle classification has always been an important link in the field of mineral processing, and the classification process of micro-fine particles directly determines the subsequent material performance. Micro-fine particles with special properties have strict requirements for their particle size, and therefore the classification process plays an important role in the resource processing and utilization of micro-fine particles.

[0003] At present, although the commonly used screening devices on the market can realize the classification of mineral micro-fine particles, the particle size of micro-fine particles is small, the specific surface area is large, and the surface moisture of mineral particles is usually high. In the classification process, it is easy to produce phenomena such as hole blocking and agglomeration, and it is not easy to pass through the screen. It is difficult for traditional screening devices, and the screening effect is very poor. The corresponding work efficiency is also greatly reduced. Moreover, the traditional screening device is mostly a mechanical transmission vibration mode for screening particles. Mechanical noise is inevitably generated during work, and the transmission components will also be worn to different degrees after long-term use. The damage of a transmission component will cause the whole device to be unable to operate normally, slow down the screening progress of the device, and reduce the screening efficiency.

[0004] Therefore, it is necessary to provide a fluidized reverse screening device and method for micro-fine particle classification to solve the above technical problems of the prior art. SUMMARY

[0005] The purpose of the present application is to overcome the problems of the prior art that the traditional screening device is not easy to classify mineral micro-fine particles, the screening effect is not ideal, and the mechanical noise is generated during work by using the mechanical transmission vibration mode, and the damage of the transmission component will slow down the screening progress.

[0006] In order to achieve the above purpose, the present application provides the following technical scheme:

[0007] The application discloses a fluidized reverse screening device for fine particle classification, which comprises a screening tank, a ventilation plate and a screening unit. The screening tank is provided with a discharge port on the top. The ventilation plate is arranged at the bottom of the inner cavity of the screening tank. The ventilation plate divides the inner cavity of the screening tank into a screening chamber and a hot air chamber. The screening tank is provided with a hot air duct which is connected to the hot air chamber and is used for conveying hot air to the hot air chamber. The hot air is blown to the screening chamber through the ventilation holes of the ventilation plate. The screening unit comprises a screen plate, an annular sealing plate and a vibrating ball. The screen plate is arranged in the screening chamber in an inclined manner. The edge of the screen plate is provided with an elastic band, and the screen plate is connected to the screening tank through the elastic band. The annular sealing plate is arranged on the upper inclined surface of the screen plate. The annular sealing plate, the screening tank and the screen plate form a slide. The bottom of the slide is provided with a bumper. The vibrating ball is shuttled in the slide by blowing air into the slide. The screen plate is vibrated by the impact of the vibrating ball on the bumper. The slide is open at the top, and the opening width is smaller than the diameter of the vibrating ball, so that the vibrating ball is prevented from jumping out of the slide. The screening tank is provided with a discharge duct which is connected to the cavity below the screen plate. The discharge port of the discharge duct is arranged at the same height as the lowest part of the screen plate.

[0008] In the fluidized reverse screening device for fine particle classification, preferably, the screening device further comprises a baffle. The baffle is in an arc shape. The baffle is arranged below the screen plate and is fixed to the screening tank.

[0009] Preferably, the baffle is arranged in an inclined manner, and the inclination direction of the baffle is consistent with that of the screen plate. The lowest part of the baffle is arranged at the same horizontal position as the discharge duct.

[0010] Preferably, the ventilation plate is in a mesh shape. The upper plate surface of the ventilation plate is covered with a ventilation cloth.

[0011] Preferably, the hot air duct is connected with a hot air machine. The screening tank is provided with a blowing pipe which is connected to the slide. A blowing machine is connected to the blowing pipe. The blowing pipe is arranged in the same direction as the extension direction of the slide.

[0012] Preferably, the screening tank is provided with a material conveying duct which is connected to the cavity between the screen plate and the ventilation plate.

[0013] Preferably, the top of the screening tank is in a conical shape. The discharge port is arranged at the middle of the top of the screening tank. A material collecting cylinder which is connected to the discharge port is arranged outside the discharge port.

[0014] The screening tank is further provided with a material collecting cylinder which is connected to the discharge hole.

[0015] Preferably, the vibrating ball is made of high-density rubber. The height of the slide is greater than the diameter of the vibrating ball.

[0016] Preferably, the outer ring of the ring-shaped sealing plate is inwardly recessed, so that the cross-sectional shape of the ring-shaped sealing plate is arc-shaped.

[0017] The application also provides a method for fluidized reverse screening of fine particles, comprising the following steps:

[0018] Step S1, loading the fine particles to be classified into the upper plate surface of the air-permeable plate through the feeding conduit to form a particle bed layer of a certain height;

[0019] Step S2, starting the air blower to blow air into the chute, and the air flow pushes the vibrating ball to shuttle in the chute, so that it impacts the impact block to make the screen plate vibrate, so as to prevent the particles from blocking the screen holes;

[0020] Step S3, starting the hot air blower to blow air into the hot air chamber, and the air flow gradually fills the hot air chamber under the action of the air-permeable plate, so that the air flow passes through the air-permeable holes on the air-permeable plate to suspend the particle layer vertically upward;

[0021] Step S4, the small particles enter the cavity above the screen plate through the screen holes on the screen plate until the discharge port, and the large particles are blocked below the screen plate and gradually flow along the inclined surface at the bottom of the screen plate to the discharge conduit.

[0022] Beneficial effects: The air-permeable plate can make the air outlet volume of the hot air chamber smaller than the air inlet volume, so that the air fills the hot air chamber, then each air-permeable hole on the air-permeable plate blows out upward hot air flow, increases the wind energy area, and makes the air flow fill the entire screening chamber, thereby providing favorable conditions for the suspended particles.

[0023] The air-permeable plate makes the hot air flow upward, the particle layer above the air-permeable plate starts to expand, the gap between the particles gradually expands, the air flow flows in the gap, so that the particles gradually suspend, during which, due to the action of gravity, small particles will also move upward through the gap between large particles, so that the particle layer as a whole gradually presents a fluidization trend, and the particles suspended in the particle layer of the screen plate will continue to be forced to float upward through the screen holes of the screen plate until the discharge port is completed to collect, and the large particles will be blocked below the screen plate and flow along the inclined surface at the bottom of the screen plate to the receiving port of the discharge conduit under the influence of its own gravity, so as to complete the collection of large particles.

[0024] The application forms a ring-shaped slide for the vibration ball to shuttle through by the ring-shaped sealing plate, the screening tank and the sieve plate, and sets the bumping block at the bottom of the slide, so that the vibration ball can bump the bumping block when shuttling in the slide to make the sieve plate vibrate, preventing the sieve plate from being blocked, thus replacing the traditional mechanical screening mode, naturally without the mechanical failure problem generated by the traditional screening mode, greatly improving the work efficiency, meanwhile, the screening unit of the device is set in the closed tank body, having strong noise reduction effect, improving the on-site working environment of the traditional screening device. BRIEF DESCRIPTION OF DRAWINGS

[0025] The drawings accompanying the specification of this application form a part thereof, serve to provide further understanding of the application, and together with the description of the exemplary embodiments of the application, serve to explain the application, and do not constitute an improper limitation on the application. Among them:

[0026] Figure 1 It is the overall schematic view of the application;

[0027] Figure 2 It is the internal schematic view of the application;

[0028] Figure 3 It is the overall schematic view of the screening unit of the application;

[0029] Figure 4 It is the top view of the baffle structure of the application;

[0030] Figure 5 It is the front view of the embodiment 3 of the application.

[0031] In the drawings: 1, screening tank; 2, discharge port; 3, air-permeable plate; 4, hot air guide pipe; 5, sieve plate; 6, ring-shaped sealing plate; 7, vibration ball; 8, elastic belt; 9, slide; 10, bumping block; 11, discharge guide pipe; 12, baffle; 13, air-permeable cloth; 14, air blowing pipe; 15, material conveying guide pipe. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the application will be described clearly and completely below, obviously, the described embodiments are only a part of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all the other embodiments obtained by the person skilled in the art belong to the protection scope of the application.

[0033] In the description of the present application, the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom" and the like 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 the present application and do not require the present application to be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. The terms "connected", "connected" used in the present application should be understood broadly, for example, it can be fixed connection, or detachable connection; it can be directly connected, or indirectly connected through intermediate components, and the specific meaning of the above terms can be understood by those skilled in the art according to the specific circumstances.

[0034] The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0035] Embodiment 1

[0036] A fluidized reverse screening device for fine particle classification, referring to Figure 1 and Figure 2 , comprising: a screening tank 1, a ventilation plate 3 located at the bottom of the inner cavity of the screening tank 1, and a screening unit located above the ventilation plate 3. Specifically, the top of the screening tank 1 is provided with a discharge port 2, and the small particles processed by the screening unit will be blown out of the discharge port 2 by the airflow. The screening tank 1 is connected with a material collecting barrel, and the material collecting barrel is connected with the discharge port 2 through a pipeline. The top of the screening tank 1 is conical, which is convenient for small particles to gather towards the discharge port 2 and speeds up the discharging speed. The inner cavity of the screening tank 1 is divided into an upper screening chamber and a lower hot air chamber by the ventilation plate 3. A material conveying pipe 15 is arranged on the screening tank 1 corresponding to the cavity between the screening unit and the ventilation plate 3, and a screw material conveyor is externally connected to continuously convey particles into the cavity through the material conveying pipe 15. A hot air pipe 4 is arranged on the outside of the screening tank 1 corresponding to the hot air chamber, and a hot air fan is externally connected to convey hot air into the hot air chamber through the hot air pipe 4. The air inlet of the hot air chamber is larger than the air outlet through the ventilation plate 3, so that the hot air can gradually fill the entire hot air chamber, and then uniformly distributed to the screening chamber through the ventilation holes on the ventilation plate 3 to form a vertical upward hot air flow. The particle layer on the ventilation plate 3 is suspended by the hot air flow, showing a fluidization trend. At the same time, the hot air flow can also continuously dry the particles to avoid the phenomenon of particle agglomeration, improve the screening effect, reduce the probability of clogging the screen holes, and speed up the screening efficiency. A layer of ventilation cloth 13 is attached to the upper surface of the ventilation plate 3, which can prevent particles from falling into the hot air chamber through the ventilation holes on the ventilation plate 3.

[0037] Referring to Figure 1 , Figure 2 and Figure 3, the screening unit comprises a sieve plate 5, an annular sealing plate 6 and a vibrating ball 7, the sieve plate 5 is oblong so as to be obliquely arranged in the screening chamber, by the oblique arrangement of the sieve plate 5, the large-size particles on the bottom surface of the sieve plate 5 are facilitated to flow downward along the inclined surface of the sieve plate 5 under the influence of gravity, and an elastic belt 8 is fixed to the edge of the sieve plate 5, the material of the elastic belt 8 can be rubber, the sieve plate 5 is flexibly connected to the inner wall of the screening tank 1 through the elastic belt 8, which provides favorable conditions for the vibration of the sieve plate 5, the annular sealing plate 6 is fixed to the upper inclined surface of the sieve plate 5 in the middle so as to be spaced from the inner wall of the screening tank 1, the outer ring surface of the annular sealing plate 6 is concave inward, and the shape of the annular sealing plate 6 is similar to that of a hub, so that the annular sealing plate 6, the screening tank 1 and the sieve plate 5 form a slide 9 for the vibrating ball 7 to shuttle, a blowing pipe 14 corresponding to the slide 9 is arranged on the screening tank 1, and a blower is connected to the blowing pipe 14 to blow air into the slide 9, and the nozzle of the blowing pipe 14 is directed in the same direction as the extension direction of the slide 9, so as to ensure that the air flow can blow the vibrating ball 7 in the slide 9, and a bumper 10 is protruded at the bottom of the slide 9, and a plurality of bumpers 10 are arranged in an annular array along the slide 9, so as to improve the vibration effect, the vibrating ball 7 is made of high-density rubber material, and when the vibrating ball 7 shuttles in the slide 9, the vibrating ball 7 will hit the bumpers 10 along the way, so that the vibrating ball 7 keeps jumping in the slide 9, so as to make the sieve plate 5 vibrate and prevent the screen hole from being blocked, wherein the slide 9 is open at the top, and the width of the slide 9 is smaller than the diameter of the vibrating ball 7, so as to limit the vibrating ball 7 from jumping out of the slide 9, and the height and the internal width of the slide 9 are greater than the diameter of the vibrating ball 7, so as to provide sufficient jumping space for the vibrating ball 7, so that the vibrating ball 7 collides with other objects when jumping to realize the vibration of the sieve plate 5, thereby replacing the traditional mechanical screening mode, and the mechanical failure problem caused by the traditional screening mode does not occur, the working efficiency is greatly improved, and the screening unit of the device is arranged in a closed tank, so that the noise reduction effect is very strong, and the working environment of the traditional screening device is improved.

[0038] Referring to Figure 2 A discharge conduit 11 corresponding to the material conveying conduit 15 is arranged on the screening tank 1, and a material receiving cylinder is connected to the discharge conduit 11 to collect the large-size particles screened by the sieve plate 5, and the nozzle of the discharge conduit 11 is arranged at the same height as the lowest part of the sieve plate 5, so that the large-size particles can directly flow into the discharge conduit 11 along the bottom surface of the sieve plate 5.

[0039] In the embodiment, two corresponding blowing pipes 14 are arranged on the screening tank 1, and the two blowing pipes 14 can form a spiral air flow flowing in a clockwise direction, the spiral air flow provides power for the vibrating ball 7 and also enables the vibrating ball 7 to make a centrifugal motion along the side wall of the screening tank 1, so as to make the vibrating ball 7 move upward together with the vertical upward air flow, the vertical upward air flow is accelerated by the centrifugal motion, and the suspension ability of the vertical upward air flow to the particles is effectively improved.

[0040] In order to further illustrate the technical scheme of the present application, the specific embodiments of the present application further provide a method for fluidized reverse screening of micro-particles.

[0041] The method in the specific embodiments of the present application comprises the following steps:

[0042] Step S1, loading the micro-particles to be classified into the upper plate surface of the air-permeable plate 3 through the feeding conduit 15 to form a particle bed layer of a certain height;

[0043] Step S2, starting the air blower to blow air into the chute 9 through the two air blowing pipes 14 at the same time to form a clockwise spiral air flow, the vibration ball 7 in the chute 9 rolls along the chute 9 under the influence of the air flow, and in the process, the vibration ball 7 jumps in the chute 9 by impacting the impact block 10 to make the sieve plate 5 vibrate;

[0044] Step S3, starting the hot air blower to convey hot air flow into the hot air chamber from the side of the screening tank 1 through the hot air conduit 4, and under the action of the air-permeable plate 3, the hot air flow will gather and quickly fill in the hot air chamber to increase the air energy area, and the hot air flow is gradually distributed to each air-permeable hole of the air-permeable plate 3 to blow towards the screening chamber to form a vertical upward air flow;

[0045] Step S4, the vertical upward air flow in step S3 blows towards the particle material layer on the upper plate surface of the air-permeable plate 3, and under the influence of the air flow, the particle material layer begins to expand, the gap between the particles gradually expands, and the air flow flows in the gap to make the particles gradually suspended, and in the process, small particles will also quickly move upwards through the gap between large particles due to the action of gravity, so that the whole particle material layer gradually presents a fluidization trend;

[0046] Step S5, the particles suspended to the particle layer at the bottom surface of the sieve plate 5 will follow the vertical upward air flow to pass through the sieve holes of the sieve plate 5 to continue to be forced to float upwards until the discharge port 2 at the top of the screening tank 1 to collect small particles, and large particles are blocked to the bottom surface of the sieve plate 5, and under the vibration action of the sieve plate 5, the phenomenon of large particles blocking the sieve holes is eliminated;

[0047] Step S6, the large particle layer blocked to the bottom surface of the sieve plate 5 in step S5 still presents fluidization under the influence of the vertical upward air flow, and under the influence of the inclined surface at the bottom of the sieve plate 5, the large particles at the high place will generate a flowing pressure on the large particles at the low place, and in addition to the influence of the gravity of the large particles themselves, the large particles will flow along the inclined surface at the bottom of the sieve plate 5 to the discharge conduit 11 to collect the large particles.

[0048] Embodiment 2 is basically the same as Embodiment 1, and the difference is that the collection effect of large particles is further improved, and for reference Figure 2 and Figure 4, The moon-shaped baffle 12 is fixed with the screening tank 1 and is arranged in the same direction as the sieve plate 5, and the lowest part of the baffle 12 is in the same horizontal position as the discharge conduit 11, and the middle part of the baffle 12 is opposite to the discharge conduit 11, so as to ensure that the large particles smoothly enter the discharge conduit 11, and the baffle 12 is arranged in an inclined shape, which can reduce the resistance to the suspended particles, and the fluidized particle layer can still flow upward along the inclined surface of the baffle 12,

[0049] By arranging the baffle 12, the vertical upward air flow at the pipe opening of the discharge conduit 11 can be reduced, when the large particles flow along the lower inclined surface of the sieve plate 5 to the upper part of the baffle 12, the vertical upward air flow is reduced, and the large particles at this position directly fall on the baffle 12 and quickly slide to the discharge conduit 11 under the assistance of the inclined surface of the baffle 12, so as to accelerate the collection speed of the large particles, and reduce the screening pressure of the bottom surface of the sieve plate 5, prevent a large number of blocked large particles from gathering on the bottom surface of the sieve plate 5, and reduce the screening effect.

[0050] In example 3, on the basis of examples 1 and 2, the small particles after screening are screened again, and the particles are further classified, referring to Figure 5 , the height of the screening tank 1 is extended, the same structure is arranged above the screening unit, the inclined direction of the upper sieve plate 5 is opposite to that of the lower sieve plate 5, and the pipe openings of the corresponding discharge conduit 11 and air blowing pipe 14 are also changed, the working principle is the same as above, and the secondary screening of the particles can fully meet the classification operation of the mineral fine particles, and greatly improves the performance of the screened material.

[0051] It can be understood that the above description is only exemplary, and the embodiments of the present application are not limited thereto.

[0052] The above description is only a preferred embodiment of the present application, and is not used to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application is within the protection scope of the claims of the present application.

Claims

1. A fluidized reverse sieving device for fine particle classification, characterized in that, The screening device includes: A screening tank, wherein the top of the screening tank is provided with a discharge port; A ventilation plate is located at the bottom of the inner cavity of the screening tank. The ventilation plate forms a screening chamber and a hot air chamber distributed vertically in the inner cavity of the screening tank. The screening tank is provided with a hot air duct that connects to the hot air chamber to deliver hot air to the hot air chamber. The hot air is blown into the screening chamber through the ventilation holes of the ventilation plate. A screening unit includes a sieve plate, an annular sealing plate, and vibrating balls. The sieve plate is inclinedly disposed in the screening chamber. An elastic band is provided on the edge of the sieve plate and is connected to the screening tank through the elastic band. The annular sealing plate is located on the upper inclined surface of the sieve plate. A slide is formed between the annular sealing plate, the screening tank, and the sieve plate. A striking block is protruding from the bottom of the slide. By blowing air into the slide, the vibrating balls shuttle through the slide. During this process, the vibrating balls strike the striking block, causing the sieve plate to vibrate. The slide has an opening at the top, the width of which is narrower than the diameter of the vibrating balls to prevent the vibrating balls from jumping out of the slide. The screening tank is provided with a discharge conduit that connects to the cavity below the screen plate, and the opening of the discharge conduit is at the same height as the lowest point of the screen plate; The screening device also includes a baffle, which is arc-shaped and located below the screen plate and fixed to the screening tank; The baffle is inclined, and the inclination direction of the baffle is the same as that of the screen plate. The lowest point of the baffle is at the same horizontal position as the discharge guide pipe.

2. The fluidized reverse sieving device for fine particle classification according to claim 1, characterized in that, The ventilation panel is mesh-like, and the upper surface of the ventilation panel is covered with a layer of ventilation cloth.

3. The fluidized reverse sieving device for fine particle classification according to claim 1, characterized in that, A hot air blower is connected to the hot air duct. A blower is connected to the sieving tank and communicates with the slide. The nozzle of the blower is oriented in the same direction as the slide.

4. A fluidized reverse sieving device for fine particle classification according to claim 1, characterized in that, The screening tank is equipped with a material conveying conduit, which connects the cavity between the screen plate and the ventilation plate.

5. A fluidized reverse sieving device for fine particle classification according to claim 1, characterized in that, The top of the screening tank is conical, and the discharge port is located in the middle of the top of the tank, and a collection cylinder connected to the discharge port is connected to it. The screening tank is also equipped with a receiving cylinder that connects to the discharge conduit.

6. A fluidized reverse sieving device for fine particle classification according to claim 1, characterized in that, The vibrating ball is made of high-density rubber, and the height of the slide is greater than the diameter of the vibrating ball.

7. A fluidized reverse sieving device for fine particle classification according to claim 1, characterized in that, The outer ring of the annular sealing plate is concave inward, making the cross-sectional shape of the annular sealing plate arc-shaped.

8. A method for fluidized reverse sieving for fine particle classification, the method comprising the fluidized reverse sieving apparatus for fine particle classification as described in any one of claims 1-7, characterized in that, The method includes the following steps: Step S1: The fine particles to be classified are loaded onto the upper surface of the ventilation plate through the conveying conduit to form a particle bed of a certain height. Step S2: Start the blower to blow air into the slide. The airflow pushes the vibrating ball through the slide, causing it to hit the impact block and vibrate the screen plate to prevent particles from clogging the screen holes. Step S3: Start the hot air blower to blow air into the hot air chamber. The airflow gradually fills the hot air chamber under the action of the ventilation plate, so that the airflow passes through the ventilation holes on the ventilation plate and suspends the granular material layer vertically upward. In step S4, small particles are carried by the airflow through the screen holes on the screen plate into the cavity above it until the discharge port. Large particles are blocked below the screen plate and gradually flow towards the discharge guide pipe along the bottom slope of the screen plate by their own gravity.

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