A coal classification system

Abstract

The application discloses a gangue particle discharging assembly, a gangue particle discharging method and a coal grading system, and belongs to the technical field of coal grading, and aims to solve the problem that gangue particles cannot be discharged in time after grading, thereby affecting the grading efficiency of coal. In the gangue particle discharging assembly, the discharging conversion plate has a discharging port mode, a channel mode and a composite mode; when the discharging conversion plate is in the discharging port mode, the discharging conversion plate covers the particle channel, and the particle discharging port is in communication with the coal grading cavity; when the discharging conversion plate is in the channel mode, the discharging conversion plate covers the particle discharging port, and the coal grading cavity is in communication with the particle channel; and when the discharging conversion plate is in the composite mode, the discharging conversion plate does not cover the particle discharging port and the particle channel, and the particle discharging port and the particle channel are both in communication with the coal grading cavity. The application can be used for discharging the gangue particles obtained after coal grading.

Description

Technical Field

[0001] This invention belongs to the field of coal grading technology, and particularly relates to a discharge component, discharge method and coal grading system for gangue particles. Background Technology

[0002] Dry coal classification is a highly efficient and environmentally friendly classification technology that classifies coal according to its density without the aid of water, through mechanical vibration and / or air separation.

[0003] For the discharge of graded gangue particles, a discharge port is usually set on the sorting chamber. However, this discharge method is simplistic and cannot be adjusted according to the amount of gangue particles in coal with different gangue particle contents. This can easily lead to gangue particles accumulating at the discharge port and failing to be discharged in time, thus affecting the coal grading efficiency. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide a discharge component, discharge method and coal grading system for gangue particles, in order to solve the problem in the prior art that the gangue particles cannot be discharged in time after grading, which affects the grading efficiency of coal.

[0005] The objective of this invention is mainly achieved through the following technical solutions.

[0006] This invention provides a discharge assembly for gangue particles, used for discharging gangue particles obtained after coal grading. The discharge assembly includes a particle discharge port, a particle channel, and a discharge conversion plate. The particle discharge port is located at the bottom of the coal grading chamber, and the particle channel is connected to the bottom of the coal grading chamber. The discharge conversion plate has a discharge port mode, a channel mode, and a combined mode. In the discharge port mode, the discharge conversion plate covers the particle channel, and the particle discharge port is connected to the coal grading chamber. In the channel mode, the discharge conversion plate covers the particle discharge port, and the coal grading chamber is connected to the particle channel. In the combined mode, the discharge conversion plate does not cover either the particle discharge port or the particle channel, and both the particle discharge port and the particle channel are connected to the coal grading chamber.

[0007] Furthermore, the discharge conversion plate is located between the particle discharge port and the particle channel, and the discharge conversion plate is rotatably connected to the coal grading chamber.

[0008] Furthermore, the discharge assembly also includes a conversion plate drive for driving the discharge conversion plate to rotate.

[0009] Furthermore, the discharge assembly also includes a mode controller and an ash detector for detecting the ash content of raw coal before grading. The mode controller is connected to the ash detector and the conversion plate drive respectively.

[0010] Furthermore, the discharge assembly also includes a discharge port belt and a channel belt. The feed end of the discharge port belt is located below the particle discharge port, and the channel belt is located below the particle channel.

[0011] The present invention also provides a method for discharging gangue particles, using the above-mentioned gangue particle discharging assembly, the discharging method comprising the following steps:

[0012] Step a: Real-time detection of raw coal ash content before grading to determine whether the raw coal ash content before grading is within the threshold range;

[0013] Step b: If the value is below the threshold range, the discharge conversion plate is in discharge port mode, the discharge conversion plate covers the particle channel, and the particle discharge port is connected to the coal grading chamber;

[0014] If it is within the threshold range, the discharge conversion plate is in channel mode, the discharge conversion plate covers the particle discharge port, and the coal grading cavity is connected to the particle channel;

[0015] If the value exceeds the threshold range, the discharge conversion plate is in composite mode. The discharge conversion plate does not cover the particle discharge port and particle channel, and both the particle discharge port and particle channel are connected to the coal grading chamber.

[0016] Furthermore, the threshold range is 20%–45%.

[0017] The present invention also provides a coal grading system, including the above-mentioned gangue particle discharge assembly.

[0018] Furthermore, the coal grading system also includes a coal grading chamber, a primary air supply unit, an orifice plate, and a secondary air supply unit. The orifice plate and the secondary air supply unit are arranged on one side of the coal grading chamber from top to bottom. The space between the top surface of the coal grading chamber and the orifice plate is the coarse coal selection chamber, the space between the orifice plate and the secondary air supply unit is the secondary grading chamber, and the space between the secondary air supply unit and the bottom surface of the coal grading chamber is the particle channel.

[0019] Furthermore, a section of the air supply component has a gap with the lower wall of the particle channel, which serves as the particle discharge port. One end of the discharge conversion plate is rotatably connected to the side of the particle channel near the gap, while the other end is a free end. One end of the air supply component near the particle discharge port is rotatably connected to the coal grading chamber, while the other end of the air supply component is a free end.

[0020] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0021] The waste rock particle discharge assembly provided by this invention is equipped with two discharge components (particle discharge port and particle channel), and controls the connection between the particle discharge port and / or particle channel and the coal grading chamber through a discharge conversion plate. The specific discharge mode can be adjusted, that is, discharge from the particle discharge port, discharge from the particle channel, or discharge from the particle discharge port and particle channel simultaneously. This allows for the selection of a suitable discharge mode according to the specific amount of waste rock particles, ensuring the timely discharge of waste rock particles from the coal grading chamber and effectively improving the coal grading efficiency.

[0022] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained through the embodiments described and the accompanying drawings, which are particularly pointed out. Attached Figure Description

[0023] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0024] Figure 1 This is a schematic diagram of the structure of the discharge assembly for gangue particles provided in Embodiment 1 of the present invention, wherein the discharge conversion plate is in discharge port mode;

[0025] Figure 2 This is a schematic diagram of the structure of the discharge assembly for gangue particles provided in Embodiment 1 of the present invention, wherein the discharge conversion plate is in channel mode;

[0026] Figure 3 This is a schematic diagram of the structure of the discharge assembly for gangue particles provided in Embodiment 1 of the present invention, wherein the discharge conversion plate is in a composite mode;

[0027] Figure 4 This is a schematic diagram of the coal grading system provided in Embodiment 3 of the present invention;

[0028] Figure 5 This is an internal schematic diagram of the coal grading system provided in Embodiment 3 of the present invention;

[0029] Figure 6 This is a schematic diagram of the main air supply chamber in the coal grading system provided in Embodiment 3 of the present invention.

[0030] Figure label:

[0031] I - First-stage classification zone; II - Roughing and cleaning coal chamber; III - Second-stage classification chamber; IV - Particle channel;

[0032] 101-Coal grading chamber; 1011-Raw coal inlet; 102-First stage air supply component; 1021-Main air supply chamber; 1022-Main air supply plate; 1023-First elastic ring; 1024-Second elastic ring; 1025-First sub-pipe; 1026-Second sub-pipe; 1027-Air pump; 103-Second stage air supply component; 104-Orifice plate; 105-Discharge conversion plate; 106-Particle discharge port. Detailed Implementation

[0033] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0034] Example 1

[0035] This embodiment provides a discharge assembly for gangue particles, used for discharging gangue particles obtained after coal grading. The discharge assembly includes a particle discharge port 106, a particle channel IV, and a discharge conversion plate 105. The particle discharge port 106 is located at the bottom of the coal grading chamber, and the particle channel IV is connected to the bottom of the coal grading chamber.

[0036] The discharge conversion plate 105 has discharge port mode, channel mode and composite mode.

[0037] The discharge conversion plate 105 is in discharge port mode, see below. Figure 1 The discharge conversion plate 105 covers the particle channel IV, and the particle discharge port 106 is connected to the coal grading chamber; the discharge conversion plate 105 is in channel mode, see [link / reference]. Figure 2 The discharge conversion plate 105 covers the particle discharge port 106, and the coal grading chamber 101 is connected to the particle channel IV; the discharge conversion plate 105 is in a composite mode, see [link / reference]. Figure 3 The discharge conversion plate 105 does not cover the particle discharge port 106 and the particle channel IV. Both the particle discharge port 106 and the particle channel IV are connected to the coal grading chamber.

[0038] Compared with the prior art, the gangue particle discharge assembly provided in this embodiment is equipped with two discharge components (particle discharge port 106 and particle channel IV), and the discharge conversion plate 105 controls the connection between particle discharge port 106 and / or particle channel IV and coal grading chamber 101, and adjusts the specific discharge mode, that is, particle discharge port 106 discharges, particle channel IV discharges, or particle discharge port 106 and particle channel IV discharge simultaneously. In this way, the appropriate discharge mode can be selected according to the specific gangue particle quantity, ensuring the timely discharge of gangue particles in coal grading chamber 101 and effectively improving coal grading efficiency.

[0039] In order to enable the mode switching of the discharge conversion plate 105, the discharge conversion plate 105 is located between the particle discharge port 106 and the particle channel IV, and the discharge conversion plate 105 is rotatably connected to the coal grading chamber 101 (e.g., the bottom surface of the coal grading chamber 101).

[0040] Accordingly, the above-mentioned discharge assembly for gangue particles also includes a conversion plate drive (e.g., a drive motor) for driving the discharge conversion plate 105 to rotate, thereby achieving mode switching of the discharge conversion plate 105.

[0041] To obtain the amount of gangue particles and select a suitable discharge method, the aforementioned gangue particle discharge assembly also includes a mode controller and an ash detector for detecting the ash content of the raw coal before grading. The mode controller is connected to both the ash detector and the conversion plate drive. In practice, the ash detector detects the ash content of the raw coal before grading in real time and transmits the data to the mode controller. The mode controller then determines whether the ash content of the raw coal before grading is within a threshold range (e.g., 20%–45%).

[0042] If the value is below the threshold range, it indicates that the ash content in the raw coal is low and the amount of gangue particles is low. The mode controller sends a discharge port mode command to the conversion plate driver, and the conversion plate driver controls the discharge conversion plate 105 to be in discharge port mode according to the discharge port mode command.

[0043] If it is within the threshold range, it means that the ash content and gangue particle content in the raw coal are in the middle range. The mode controller sends the channel mode command to the conversion plate driver, and the conversion plate driver controls the discharge conversion plate 105 to be in channel mode according to the channel mode command.

[0044] If the value is higher than the threshold range, it indicates that there is a lot of ash in the raw coal and a lot of gangue particles. The mode controller sends a composite mode command to the conversion plate driver, and the conversion plate driver controls the discharge conversion plate 105 to be in composite mode according to the composite mode command.

[0045] It should be noted that the threshold range refers to the ash content range formed by the ash content corresponding to the switch from composite mode to channel mode and the ash content corresponding to the switch from channel mode to discharge port mode.

[0046] In order to facilitate the timely transportation of gangue particles discharged from the particle discharge port 106 and the particle channel IV, the above-mentioned gangue particle discharge assembly also includes a discharge port belt and a channel belt. The feed end of the discharge port belt is located below the particle discharge port 106, and the channel belt is located below the particle channel IV.

[0047] Example 2

[0048] This embodiment provides a method for discharging gangue particles, using the gangue particle discharging assembly provided in Embodiment 1. The discharging method includes the following steps:

[0049] Step a: Real-time detection of raw coal ash content before grading to determine whether the raw coal ash content before grading is within the threshold range;

[0050] Step b: If the value is below the threshold range, the discharge conversion plate 105 is in discharge port mode, the discharge conversion plate 105 covers the particle channel IV, and the particle discharge port 106 is connected to the coal grading chamber.

[0051] If it is within the threshold range, the discharge conversion plate 105 is in channel mode, the discharge conversion plate 105 covers the particle discharge port 106, and the coal grading cavity 101 is connected to the particle channel IV.

[0052] If the value exceeds the threshold range, the discharge conversion plate 105 is in composite mode. The discharge conversion plate 105 does not cover the particle discharge port 106 and the particle channel IV. Both the particle discharge port 106 and the particle channel IV are connected to the coal grading chamber 101.

[0053] Compared with the prior art, the beneficial effects of the gangue particle discharge method provided in this embodiment are basically the same as those of the gangue particle discharge assembly provided in Embodiment 1, and will not be described in detail here.

[0054] Example 3

[0055] This embodiment provides a coal grading system, see [link / reference] Figures 4 to 5 It includes a coal grading chamber 101, a first-stage air supply component 102, an orifice plate 104, a second-stage air supply component 103, and a discharge assembly for gangue particles provided in Example 1.

[0056] The orifice plate 104 and the secondary air supply component 103 are arranged from top to bottom on one side of the coal grading chamber 101. The inner cavity of the coal grading chamber 101 is divided into a primary grading zone I without the orifice plate 104 and the secondary air supply component 103, and a secondary grading zone with the orifice plate 104 and the secondary air supply component 103. The space between the top surface of the secondary grading zone and the orifice plate 104 is the coarse coal selection chamber II, the space between the orifice plate 104 and the secondary air supply component 103 is the secondary grading chamber III, and the space between the secondary air supply component 103 and the bottom surface of the secondary grading zone is the particle channel IV. The primary grading zone I has a raw coal inlet 1011. The air supply component 102 has a gap with the lower wall of the particle channel IV, which serves as the particle discharge port 106. One end of the discharge conversion plate 105 is rotatably connected to the side of the particle channel IV near the gap, and the other end is a free end. The raw coal inlet 1011 is located at the top of the first-stage classification zone I, away from the second-stage classification zone. The particle discharge port 106 is located at the bottom of the first-stage classification zone I, near the second-stage classification zone. The roughing and cleaning coal chamber II has a roughing and cleaning coal discharge port, and the second-stage classification chamber III has a middlings discharge port and a re-selected clean coal discharge port. Considering the density of middlings and re-selected clean coal, the re-selected clean coal discharge port is located above the middlings discharge port.

[0057] During implementation, raw coal enters the first-stage grading zone I through the raw coal inlet 1011, and airflow is supplied into the first-stage grading zone I through the first-stage air supply unit 102. Within the first-stage grading zone I, the raw coal is subjected to the combined force field of excitation force and airflow, resulting in stratification along the longitudinal direction within the coal grading chamber 101 based on density differences. The lighter-density coarse coal remains in the upper part of the first-stage grading zone I, while the heavier-density gangue particles settle in the lower part of the first-stage grading zone I. The medium-density mixture of middlings and re-selected coal is suspended in the middle position of the first-stage grading zone I. With the continuous addition of raw coal, the gangue particles, coarse coal, middlings, and re-selected coal in the first-stage grading zone I are pushed by the newly added raw coal. Under the influence of the excitation force, the material migrates horizontally. The coarse coal enters the coarse coal chamber II and is then discharged from the discharge port of the coarse coal chamber II as a refined coal product. The gangue particles are discharged from the particle discharge port 106 and / or the particle channel IV. The airflow is supplied from the second-stage air supply component 103 into the second-stage classification chamber III. The middlings and re-selected refined coal enter the second-stage classification chamber III for second-stage separation. The combined force field of the excitation force and the airflow of the middlings and re-selected refined coal mixture causes further stratification. The lighter-density re-selected refined coal remains in the upper part of the second-stage classification chamber III and is then discharged from the re-selected refined coal discharge port. The heavier-density middlings remains in the lower part of the second-stage classification chamber III and is then discharged from the middlings discharge port.

[0058] The aforementioned coal grading system, through the setting of orifice plate 104 and two-stage air supply component 103, divides the coal grading chamber 101 into a primary grading zone I, a coarse and fine coal chamber II, a secondary grading chamber III, and a particle channel IV. Raw coal enters the primary grading zone I for primary separation, achieving the separation of gangue particles, coarse and fine coal, and the mixture of middlings and re-selected fine coal. The mixture of middlings and re-selected fine coal enters the secondary grading chamber III for secondary separation, achieving the separation of middlings and re-selected fine coal. Simultaneously, it achieves thorough separation of gangue particles, coarse and fine coal, and middlings. The process is simple, the separation cost is low, and it can solve the problems of low separation accuracy and serious resource waste in 0.5–13 mm fine coal.

[0059] Specifically, the structure of a section of the air supply component 102 includes a main air supply chamber 1021 fixedly connected to the coal grading chamber 101 and a main air supply plate 1022 covering the air outlet of the main air supply chamber 1021, with main air supply holes opened on the main air supply plate 1022.

[0060] Considering that the gangue particles will move along the main air supply plate 1022 to the particle discharge port 106 and / or particle channel IV for discharge, in order to adjust the discharge speed of the gangue particles, one end of the main air supply plate 1022 near the particle discharge port 106 is rotatably connected to the coal grading chamber 101, and the other end of the main air supply plate 1022 is a free end. When the amount of gangue particles is greater than the gangue threshold, the main air supply plate 1022 can be driven to rotate, increasing the tilt angle of the main air supply plate 1022, accelerating the migration speed of the gangue particles, and avoiding the phenomenon of bed crushing.

[0061] In order to adjust the tilt angle of the main air supply panel 1022 using airflow, for the case where there is only one main air supply chamber 1021, the structure of the main air supply chamber 1021 is detailed below. Figure 6 The main air supply chamber 1021 includes a first elastic ring 1023, a second elastic ring 1024, a first sub-pipe 1025, and a second sub-pipe 1026 sleeved outside the first sub-pipe 1025, with a gap between the second sub-pipe 1026 and the first sub-pipe 1025. The main air supply plate 1022 is divided into a central area and a surrounding area. The surrounding area has main air supply holes, while the central area does not have main air supply holes. The air outlet of the first sub-pipe 1025 covers the central area and is connected to the edge of the central area through the first elastic ring 1023. An air pump 1027 is installed on the first sub-pipe 1025, and the air outlet of the second sub-pipe 1026 covers the surrounding area and is connected to the edge of the surrounding area through the second elastic ring 1024.

[0062] When there is no need to increase the tilt angle of the main air supply plate 1022, only the second sub-pipe 1026 supplies air to the first graded zone I through the main air supply hole. When it is necessary to increase the tilt angle of the main air supply plate 1022, the suction pump 1027 is turned on, and airflow is simultaneously introduced into the first sub-pipe 1025 and the second sub-pipe 1026, which increases the length of the first elastic ring 1023 and the second elastic ring 1024, causing the main air supply plate 1022 to rotate clockwise and increase its tilt angle. In this way, through the cooperation of the first sub-pipe 1025 and the second sub-pipe 1026, the pressure of the airflow can drive the main air supply plate 1022 to rotate, thereby realizing the adjustment of the tilt angle of the main air supply plate 1022 by airflow without the need for other additional main air supply plate 1022 drive mechanisms.

[0063] For the structure of the two-stage air supply component 103, in order to improve the uniformity of air supply, it specifically includes an air supply trough, a plate and a dividing rib. The dividing rib is set in the air supply trough to divide the air supply trough into multiple air supply sub-troughs. The air supply of the multiple air supply sub-troughs is set independently. Each air supply sub-trough has an air inlet hole. The plate covers the opening of the air supply trough, and the air supply hole is set on the plate.

[0064] In order to improve the sorting accuracy and avoid the middlings and re-selected clean coal mixture from clogging the side wall of the re-selection air supply plate and causing material back mixing, the aforementioned re-selection air supply plate is inclined toward one side of the first grading zone I, thereby forming a tip, which facilitates the precise sorting of gangue particles and middlings and re-selected clean coal mixture.

[0065] To adjust the height of the separation layer between the middlings and re-selected clean coal mixture and the coarse clean coal, the orifice plate 104 is rotatably connected to the side wall of the coal grading chamber 101. The relative rotation of the orifice plate 104 adjusts the inlet size of the coarse clean coal chamber II and the second-stage grading chamber III, thereby adjusting the height of the separation layer between the middlings and re-selected clean coal mixture and the coarse clean coal. Thus, if the coarse clean coal content in the raw coal exceeds the threshold range for coarse clean coal, the orifice plate 104 is rotated so that its free end is lower than its connecting end, increasing the inlet of the coarse clean coal chamber II and increasing the throughput of coarse clean coal. Conversely, if the middlings and re-selected clean coal content in the raw coal exceeds the threshold range for the mixture, the orifice plate 104 is rotated so that its free end is higher than its connecting end, increasing the inlet of the second-stage grading chamber III and increasing the throughput of the middlings and re-selected clean coal mixture.

[0066] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A coal grading system, characterized in that, The system includes a coal grading chamber, a primary air supply unit, an orifice plate, a secondary air supply unit, and a discharge assembly for gangue particles. The discharge assembly is used to discharge the gangue particles obtained after coal grading. The discharge assembly includes a particle discharge port, a particle channel, and a discharge conversion plate. The particle discharge port is located at the bottom of the coal grading chamber, and the particle channel is connected to the bottom of the coal grading chamber. The discharge conversion plate has three modes: discharge port mode, channel mode, and combined mode. In discharge port mode, the discharge conversion plate covers the particle channel, and the particle discharge port is connected to the coal grading chamber. In the channel mode, the discharge conversion plate covers the particle discharge port, and the coal grading chamber is connected to the particle channel; in the composite mode, the discharge conversion plate does not cover the particle discharge port and the particle channel, and both the particle discharge port and the particle channel are connected to the coal grading chamber; the orifice plate and the two-stage air supply component are arranged from top to bottom on one side of the coal grading chamber, the space between the top surface of the coal grading chamber and the orifice plate is the coarse and fine coal chamber, the space between the orifice plate and the two-stage air supply component is the two-stage grading chamber, and the space between the two-stage air supply component and the bottom surface of the coal grading chamber is the particle channel. The air supply component has a gap with the lower wall of the particle channel, and the gap serves as a particle discharge port; one end of the discharge conversion plate is rotatably connected to the side of the particle channel near the gap, and the other end is a free end; A section of the air supply component includes a main air supply chamber fixedly connected to the coal grading chamber and a main air supply plate covering the air outlet of the main air supply chamber, with main air supply holes opened on the main air supply plate; one end of the main air supply plate near the particle discharge port is rotatably connected to the coal grading chamber, and the other end of the main air supply plate is a free end; there is one main air supply chamber, including a first elastic ring, a second elastic ring, a first sub-pipe, and a second sub-pipe sleeved outside the first sub-pipe, with a gap between the second sub-pipe and the first sub-pipe; the main air supply plate is divided into a central area and a surrounding area around the central area, with main air supply holes opened in the surrounding area and no main air supply holes set in the central area, the air outlet of the first sub-pipe covering the central area and connected to the edge of the central area through the first elastic ring; an air pump is installed on the first sub-pipe, and the air outlet of the second sub-pipe covering the surrounding area and connected to the edge of the surrounding area through the second elastic ring.

2. The coal grading system according to claim 1, characterized in that, The discharge conversion plate is located between the particle discharge port and the particle channel, and the discharge conversion plate is rotatably connected to the coal grading chamber.

3. The coal grading system according to claim 1, characterized in that, The discharge assembly also includes a conversion plate drive for driving the discharge conversion plate to rotate.

4. The coal grading system according to claim 3, characterized in that, The discharge assembly also includes a mode controller and an ash detector for detecting the ash content of raw coal before grading. The mode controller is connected to the ash detector and the conversion plate drive respectively.

5. The coal grading system according to claim 1, characterized in that, The discharge assembly also includes a discharge port belt and a channel belt. The feed end of the discharge port belt is located below the particle discharge port, and the channel belt is located below the particle channel.

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