A fine-grained coal spiral airflow separator

Abstract

The present invention belongs to the technical field of dry sorting of fine coal. Under the premise of ensuring sorting accuracy, it solves the problems of difficult density control and complex process of dry sorting of fine coal. A fine coal spiral airflow sorting machine is provided. The inner cavity of the spiral airflow sorting trough is divided by several air distribution plates along the trough height direction. The air distribution plates and the inner edge plates, outer edge plates and trough top of the spiral airflow sorting trough form a chamber as a sorting chamber. The air distribution plates and the inner edge plates, outer edge plates and trough bottom of the spiral airflow sorting trough form a chamber as a blast chamber. The bottom of the blast chamber is provided with several bottom airflow nozzles that provide vertical pulse airflow to the sorting chamber at intervals along the spiral line direction of the spiral airflow sorting trough. The air distribution plates that constitute the sorting chamber are provided with multiple planar airflow hole groups in sequence along the radial direction of the spiral airflow sorting trough. The present invention can realize the simultaneous vertical stratification and radial separation of particles, without the need to use a high-density fluidized bed layer configured with a weighting material such as magnetite powder, and can streamline the sorting process.

Description

Technical Field

[0001] The invention belongs to the technical field of fine coal dry separation, and in particular relates to a fine coal spiral airflow separator. Background Art

[0002] Traditional spiral separators, also known as spiral concentrators or spiral chutes, are thin-film separation equipment commonly used to separate useful and unusable minerals from coal, metal ore, coastal sand deposits, and gasified slag. These devices use water as the working medium, separating particles in the water (or ore slurry) according to their density characteristics. The spiral separator's unique radial circulation allows for radial separation of light and heavy particles.

[0003] Currently, dry coal separation has achieved preliminary separation of lump coal (larger than 6mm), but research on fine coal (smaller than 6mm) remains in the laboratory stage. Common fine coal gas flow separation equipment is primarily air-dense medium fluidized bed separators, including air-dense medium fluidized beds and pulsating gas-solid fluidized beds. However, this type of equipment requires the addition of weighting agents such as fine magnetite powder to form a fluidized bed with a high separation density. The separation relies on the Archimedean principle to achieve particle stratification, and then uses external means such as scrapers to separate the light and heavy particles. This results in high production costs and complex processes, and subsequent product operation stages make it difficult to separate the weighting agents from the fine coal. Another common fine coal dry separation technology is composite dry separation, which uses vibration and wind power to induce the fine coal to form a self-generating medium layer with a certain density. This separation is then achieved based on the shaking table separation principle. However, this equipment suffers from complex equipment structure, unstable self-generating medium, and low separation accuracy. Summary of the Invention

[0004] In order to solve at least one of the above technical problems existing in the prior art, the present invention provides a fine-grained coal spiral airflow separator.

[0005] The present invention is implemented by the following technical solution: a fine-grained coal spiral airflow separator, comprising a spiral airflow separator, a feeding device, a cutting device and a bracket; the feeding device and the cutting device are respectively connected to the feeding end and the discharging end of the spiral airflow separator, the spiral airflow separator is spirally arranged on the inner side of the bracket, the inner cavity of the spiral airflow separator is separated by a plurality of air distribution plates along the height direction of the trough, wherein the cavity formed by the air distribution plate and the inner edge plate, outer edge plate and trough top of the spiral airflow separator serves as a separator, and the cavity formed by the air distribution plate and the inner edge plate, outer edge plate and trough bottom of the spiral airflow separator serves as a blast chamber, and the blast chamber is arranged along the height direction of the spiral airflow separator. It is radially divided into an inner blast chamber and an outer blast chamber. The widths of the inner blast chamber and the outer blast chamber gradually decrease in the direction away from the trough top. A number of trough bottom airflow nozzles are arranged at intervals along the spiral direction of the spiral airflow sorting trough at the bottom of the blast chamber to provide vertical pulse airflow to the sorting chamber. A plurality of planar airflow hole groups are arranged in sequence along the radial direction of the spiral airflow sorting trough on the air distribution plate that constitutes the sorting chamber. Along the direction away from the inner edge of the spiral airflow sorting trough, the distance between adjacent airflow holes in different planar airflow hole groups gradually decreases, and the distance between adjacent airflow holes in the same planar airflow hole group is the same. The airflow holes serve as rising channels for the airflow in the blast chamber.

[0006] Preferably, the upper portion of the inner edge plate of the spiral airflow sorting trough constituting the sorting chamber is provided with multiple groups of upper-layer airflow nozzles at intervals along the spiral direction, and the lower portion of the outer edge plate of the spiral airflow sorting trough constituting the sorting chamber is provided with multiple groups of lower-layer airflow nozzles at intervals along the spiral direction; the vertical pulses of the airflow nozzles at the bottom of the trough are used to fluidize the material in the sorting chamber, thereby generating radial circulation on the spiral trough surface; at the same time, the upper-layer airflow nozzles are used to blow the upper layer of material in the sorting chamber toward the outer edge of the spiral airflow sorting trough, and the lower-layer airflow nozzles are used to blow the lower layer of material in the sorting chamber toward the inner edge of the spiral airflow sorting trough, further strengthening the radial circulation in the cross section. In the fluidized bed, the particles are stratified by density by relying on their own settling characteristics and the action of the pulsating airflow, and radial wind force is achieved under the action of the radial circulation.

[0007] Preferably, two air distribution plates are provided in the inner cavity of the spiral airflow sorting trough along the trough height direction, and the chamber enclosed by the two air distribution plates and the inner edge plate and outer edge plate of the spiral airflow sorting trough serves as an air distribution chamber; the air distribution chamber is divided by a partition into an inner air distribution chamber connected to the inner blast chamber and an outer air distribution chamber connected to the outer blast chamber, and the air distribution plate used to separate the blast chamber and the air distribution chamber is densely spaced with air flow channels and the air distribution plate is divided into two sections by a partition.

[0008] Preferably, the aperture of the air flow channel on the air distribution plate near the bottom of the spiral air flow sorting trough is 1-2 times the aperture of the air flow hole on the air distribution plate near the top of the spiral air flow sorting trough.

[0009] Preferably, the cross-sectional shapes of the inner blast chamber and the outer blast chamber are both inverted trapezoidal structures, and the length of the upper side of the inverted trapezoidal cross-section of the outer blast chamber is 1.5 times the length of the upper side of the inverted trapezoidal cross-section of the inner blast chamber.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] The present invention introduces a vertical pulsating airflow into the sorting chamber, which promotes the fluidization of the material to be selected and is conducive to the generation of radial circulation in the cross section; at the same time, the pulsating airflow strengthens the effect of vertical stratification of particles according to density; at the same time, based on the unique radial circulation of the fluid in the spiral groove and the airflow injection devices arranged on both sides of the sorting chamber, the vertical stratification and radial separation of the particles can be achieved simultaneously, effectively improving the particle sorting accuracy.

[0012] The present invention is based on the basic principle of mineral separation of traditional water-medium spiral separators. Through special design of the trough surface structure, a new type of spiral airflow separator with air as the working medium is realized. It can be used for dry separation of fine-grained coal, as well as dry separation of other fine-grained minerals and waste residues. Compared with traditional fine-grained coal dry separation equipment, it does not require the use of weighting materials, has low production costs and simple processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0015] Figure 2 Schematic diagram of the internal structure of the spiral airflow separation tank of the present invention;

[0016] Figure 3 Schematic diagram of the chamber distribution of the spiral airflow sorting tank of the present invention;

[0017] Figure 4 This is a schematic structural diagram of the air distribution plate near the bottom of the spiral airflow separation trough in the present invention;

[0018] Figure 5 It is a structural schematic diagram of the air distribution plate near the top of the spiral airflow sorting trough in the present invention.

[0019] In the figure: 1- spiral airflow sorting trough; 2- feeding device; 3- material cutting device; 4- bracket; 5- air distribution plate; 6- sorting chamber; 7.1- inner blast chamber; 7.2- outer blast chamber; 8- air flow nozzle at the bottom of the trough; 9- air flow hole; 10- upper layer air flow nozzle; 11- lower layer air flow nozzle; 12.1- inner air distribution chamber; 12.2- outer air distribution chamber; 13- partition; 14- air flow channel. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention are clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other implementations derived by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of protection of the present invention.

[0021] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which the present invention can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should fall within the scope of the technical content disclosed in the present invention without affecting the efficacy and purpose that can be achieved by the present invention. It should be noted that in this specification, relational terms such as first and second are only used to distinguish one entity from several other entities, and do not necessarily require or imply any actual relationship or order between these entities.

[0022] The present invention provides an embodiment:

[0023] like Figures 1 to 5As shown, a fine-grained coal spiral airflow separator comprises a spiral airflow separator 1, a feeding device 2, a cutting device 3 and a bracket 4; the feeding device 2 and the cutting device 3 are respectively connected to the feeding end and the discharging end of the spiral airflow separator 1, the spiral airflow separator 1 is spirally arranged on the inner side of the bracket 4, and the inner cavity of the spiral airflow separator 1 is separated by a plurality of air distribution plates 5 along the groove height direction, wherein the air distribution plate 5 and the inner edge plate, outer edge plate and groove top of the spiral airflow separator 1 form a chamber as a separator 6, and the air distribution plate 5 and the inner edge plate, outer edge plate and groove bottom of the spiral airflow separator 1 form a chamber as a blast chamber, and the blast chamber is divided into an inner blast chamber along the radial direction of the spiral airflow separator 1. The widths of the chamber 7.1 and the outer blast chamber 7.2, as well as the inner blast chamber 7.1 and the outer blast chamber 7.2, gradually decrease in the direction away from the top of the trough. A number of trough bottom airflow nozzles 8 for providing vertical pulsed airflow to the sorting chamber 6 are arranged at intervals at the bottom of the blast chamber along the spiral direction of the spiral airflow sorting trough 1. A plurality of planar airflow hole groups are sequentially arranged on the air distribution plate 5 constituting the sorting chamber 6 along the radial direction of the spiral airflow sorting trough 1. In the direction away from the inner edge of the spiral airflow sorting trough 1, the spacing between adjacent airflow holes 9 in different planar airflow hole groups gradually decreases, and the spacing between adjacent airflow holes 9 in the same planar airflow hole group is the same. The airflow holes 9 serve as an ascending channel for the airflow in the blast chamber.

[0024] The main function of the airflow nozzle 8 at the bottom of the trough is to provide vertical pulsed airflow to the sorting chamber 6. It should be noted that the airflow nozzle 8 at the bottom of the trough is set at different radial positions, and the blast chamber is divided into an inner blast chamber 7.1 and an outer blast chamber 7.2 along the radial direction of the spiral airflow sorting trough 1. Considering that the properties of the particles distributed at the inner and outer edges of the spiral airflow sorting trough 1 are different, different pulsating airflows need to be sprayed on different particles.

[0025] In this embodiment, two air distribution plates 5 are provided in the inner cavity of the spiral airflow sorting trough 1 along the trough height direction, and the chamber surrounded by the two air distribution plates 5 and the inner edge plate and outer edge plate of the spiral airflow sorting trough 1 serves as an air distribution chamber; the air distribution chamber is divided by a partition 13 into an inner air distribution chamber 12.1 connected to the inner blast chamber 7.1 and an outer air distribution chamber 12.2 connected to the outer blast chamber 7.2. The air distribution plates 5 used to separate the blast chamber and the air distribution chamber are densely spaced with air flow channels 14, and the air distribution plates 5 are divided into two sections by the partition 13. The air flow channels 14 serve as rising channels for the air flow in the blast chamber. The purpose of the air distribution chamber is to further make the air flow rise evenly along the aperture of the air distribution plates 5.

[0026] The cross-sections of both the inner and outer blast chambers 7.1, 7.2 are inverted trapezoidal structures, with the upper edge of the outer blast chamber 7.2's inverted trapezoidal cross-section being 1.5 times the length of the upper edge of the inner blast chamber 7.1's inverted trapezoidal cross-section. The diameter of the airflow passages 14 on the air distribution plate 5 near the bottom of the spiral airflow sorting trough 1 is 1-2 times the diameter of the airflow holes 9 on the air distribution plate 5 near the top of the spiral airflow sorting trough 1.

[0027] A plurality of groups of upper-layer airflow nozzles 10 are arranged at intervals along the spiral direction on the upper portion of the inner edge plate of the spiral airflow sorting trough 1 constituting the sorting chamber 6, and a plurality of groups of lower-layer airflow nozzles 11 are arranged at intervals along the spiral direction on the lower portion of the outer edge plate of the spiral airflow sorting trough 1 constituting the sorting chamber 6; the vertical pulse of the airflow nozzle 8 at the bottom of the trough is used to stratify the material in the sorting chamber 6 according to density, the upper-layer airflow nozzle 10 is used to blow the upper-layer material in the sorting chamber 6 toward the outer edge of the spiral airflow sorting trough 1, and the lower-layer airflow nozzle 11 is used to blow the lower-layer material in the sorting chamber 6 toward the inner edge of the spiral airflow sorting trough 1.

[0028] Working principle:

[0029] Compressed air, carrying a certain amount of fine coal (less than 6mm), enters the separation chamber 6 from the equipment's feed device 2 at a constant speed. Under the influence of the airflow, the particles move in a spiral along the separation chamber 6. Simultaneously, the airflow nozzles 8 at the bottom of the trough spray compressed air into the blast chamber according to a specific pulsating pattern. This airflow passes through the air distribution plate 5, the air distribution chamber, and the air distribution plate 5 in sequence before entering the separation chamber 6. This vertical pulsating action fluidizes the material in the separation chamber 6 and stratifies it according to density, causing low-density light particles to settle in the upper layer and high-density heavy particles to settle in the lower layer.

[0030] Due to the unique curved surface structure of the spiral airflow sorting trough 1, a special radial circulation will be generated when the spiral airflow moves downward in the sorting chamber 6. This radial circulation will cause the light particles in the upper layer to move radially toward the outer edge and the heavy particles in the lower layer to move radially toward the inner edge, thereby realizing the sorting of particles according to density.

[0031] The upper air flow nozzle 10 and the lower air flow nozzle 11 arranged on both sides of the sorting chamber 6 have the function of blowing the upper layer material in the sorting chamber 6 toward the outer edge of the spiral air flow sorting trough 1 and blowing the lower layer material toward the inner edge of the spiral air flow sorting trough 1, thereby strengthening the radial circulation.

[0032] Whether to activate the upper and lower airflow nozzles 10, 11, and whether these nozzles should cross-jet with the bottom airflow nozzles 8 to prevent interference between the two airflows, depends on the distribution of the material in the sorting chamber 6. Finally, the material is separated radially at the cutter 3, with the outer edge being treated as the light product and the inner edge as the heavy product. Depending on actual needs, multiple radial partitions can be installed to produce three or more product types: low-density, intermediate-density, and high-density.

[0033] The fine coal dry sorting machine proposed in the present invention can be used to sort 6-1mm fine coal. The core is to construct a special closed sorting trough, which is composed of a blast chamber, an air distribution chamber, and a sorting chamber 6 from bottom to top. An air distribution plate is used to evenly spray the airflow of the blast chamber into the sorting chamber 6, thereby fluidizing the material in the sorting chamber 6 and realizing stratification in the longitudinal direction. Air flow nozzles are arranged on both sides of the sorting chamber 6, which can be used as a device to enhance radial circulation. Together with the pulsed airflow at the bottom, a cross-injection composite flow field can be formed to quickly transport the stratified particles away, avoid invalid pulsation in the stratified interval, and reduce the occurrence of mismatching. The selection of the air distribution plate 5 can be based on the material properties, or only one air distribution plate 5 or multiple air distribution plates 5 can be used. The aperture of the air distribution plate 5, and the combination of apertures when using multiple air distribution plates 5, need to be determined according to the movement state of the particles in the sorting chamber 6.

[0034] The foregoing description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be readily conceived by a person skilled in the art within the technical scope disclosed herein should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A fine-grained coal spiral airflow separator, characterized by: It comprises a spiral airflow sorting trough (1), a feeding device (2), a cutting device (3) and a bracket (4); The feeding device (2) and the cutting device (3) are respectively connected to the feeding end and the discharging end of the spiral airflow sorting trough (1). The spiral airflow sorting trough (1) is arranged in a spiral shape on the inner side of the bracket (4). The inner cavity of the spiral airflow sorting trough (1) is separated by a plurality of air distribution plates (5) along the trough height direction. The cavity formed by the air distribution plates (5) and the inner edge plates, outer edge plates and trough top of the spiral airflow sorting trough (1) serves as the sorting chamber (6). The cavity formed by the air distribution plates (5) and the inner edge plates, outer edge plates and trough bottom of the spiral airflow sorting trough (1) serves as the sorting chamber (6). The chamber is used as a blast chamber, and the blast chamber is divided into an inner blast chamber (7.1) and an outer blast chamber (7.2) along the radial direction of the spiral airflow sorting trough (1). The width of the inner blast chamber (7.1) and the outer blast chamber (7.2) is determined according to the distribution of the material to be selected in the bed layer. The bottom of the blast chamber is provided with a plurality of slot bottom airflow nozzles (8) for providing vertical pulse airflow to the sorting chamber (6) at intervals along the spiral line direction of the spiral airflow sorting trough (1). The air distribution plate (5) constituting the sorting chamber (6) is provided along the spiral airflow sorting trough (1). ) are provided with a plurality of planar airflow hole groups in sequence in the radial direction, and the spacing between adjacent airflow holes (9) in different planar airflow hole groups gradually decreases in the direction away from the inner edge of the spiral airflow sorting groove (1), and the spacing between adjacent airflow holes (9) in the same planar airflow hole group is the same, and the airflow holes (9) serve as the rising channel of the airflow in the blast chamber; the upper part of the inner edge plate of the spiral airflow sorting groove (1) constituting the sorting chamber (6) is provided with a plurality of groups of upper airflow nozzles (10) at intervals along the spiral direction, and .... A plurality of lower-layer airflow nozzles (11) are arranged at intervals along a spiral direction at the lower portion of the outer edge plate of the flow separation trough (1); the vertical pulses of the airflow nozzles (8) at the bottom of the trough are used to fluidize the material in the separation chamber (6); the upper-layer airflow nozzles (10) are used to blow the upper-layer material in the separation chamber (6) toward the outer edge of the spiral airflow separation trough (1); and the lower-layer airflow nozzles (11) are used to blow the lower-layer material in the separation chamber (6) toward the inner edge of the spiral airflow separation trough (1), thereby strengthening the radial circulation of the cross section of the spiral airflow separation trough (1).

2. The fine coal spiral airflow separator according to claim 1, characterized in that: Two air distribution plates (5) are provided in the inner cavity of the spiral air flow separation trough (1) along the trough height direction, and the cavity enclosed by the two air distribution plates (5) and the inner edge plate and outer edge plate of the spiral air flow separation trough (1) serves as an air distribution chamber; The air distribution chamber is divided into an inner air distribution chamber (12.1) communicating with the inner blast chamber (7.1) and an outer air distribution chamber (12.2) communicating with the outer blast chamber (7.2) by a partition (13). Air flow channels (14) are densely spaced on an air distribution plate (5) for separating the blast chamber and the air distribution chamber, and the air distribution plate (5) is divided into two sections by the partition (13).

3. The fine coal spiral airflow separator according to claim 2, characterized in that: The aperture of the air flow channel (14) on the air distribution plate (5) near the bottom of the spiral air flow separation tank (1) is 1-2 times the aperture of the air flow hole (9) on the air distribution plate (5) near the top of the spiral air flow separation tank (1).

4. The fine coal spiral airflow separator according to claim 1, characterized in that: The cross-sectional shapes of the inner blast chamber (7.1) and the outer blast chamber (7.2) are both inverted trapezoidal structures, and the length of the upper side of the inverted trapezoidal cross-section of the outer blast chamber (7.2) is 1.5 times the length of the upper side of the inverted trapezoidal cross-section of the inner blast chamber (7.1).

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