Flotation bed for continuously extracting gangue from raw coal and method for continuously extracting gangue
By designing a floating bed that uses the granular layer and the medium particle layer, the existing coal dry method floating bed is sealing, noise and wear when the pillar is adopted. Cost operation.
Patent Information
- Application Number
- CN202411472867.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-22
- Publication Date
- 2025-01-21
AI Technical Summary
The existing coal dry flotation beds have shortcomings such as sealing problems, noise pollution, wear, high failure rate and high operating costs when harvesting gangue.
A flotation bed is designed. By setting up a gangue outflow port at the lower part of the flotation bed, and utilizing the combination of material sealing particle layer and medium particle layer, continuous mining of gangue is achieved, avoiding the use of mechanical equipment.
It realizes the continuous mining of gangue, avoids noise pollution and wear, reduces investment and operating costs, extends the service life of equipment, and reduces dust pollution.
Smart Images
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of green coal sorting and processing, in particular to a flotation bed for continuously mining gangue from raw coal and a method for continuously mining gangue. Background Art
[0002] my country's energy endowment is characterized by rich coal, poor oil and little gas. For a long time in the future, coal will still occupy an absolute dominant position in my country's energy structure. In order to achieve sustainable development and environmental protection, the efficient and clean utilization of coal resources is imperative and urgent. The raw coal mined from coal mines often contains a large amount of gangue. Separating this part of the gangue before the subsequent use of the raw coal (i.e. coal sorting) is the first step to achieve efficient and clean utilization of coal resources. In addition, coal sorting at the coal production site (rather than the use site) can not only save transportation costs, but also backfill the sorted gangue on site to prevent environmental and ecological problems such as surface collapse in the mining area.
[0003] The current coal separation process is mainly based on the density difference between gangue and coal (the former is denser than the latter), so it is also called flotation process. In situations where the application of wet coal separation process is limited (such as arid and cold regions), dry flotation process is an effective alternative, that is, using a group of particles in a bubbling fluidized state as the flotation medium.
[0004] Chinese patent CN116351706A discloses an existing coal dry flotation bed ( Figure 1 ), the flotation bed is filled with specific medium particles (such as magnetite powder), and air is introduced into the lower part to keep the medium particles in a stable fluidized state. Then, the operating gas velocity is reasonably adjusted to make the bed density between the density of gangue and coal. After that, the crushed raw coal is sent into the flotation bed from the middle, and the heavier gangue particles will gradually settle on the gas distribution plate, while the lighter coal particles will float to the surface of the bed. In order to realize the continuous operation of the above-mentioned dry flotation process, it is necessary to continuously extract coal particles from the upper part of the bed, which can be simply achieved by overflow. At the same time, it is also necessary to continuously extract gangue particles from the bottom of the bed, and the current method mainly relies on mechanical equipment to achieve this. Existing equipment for extracting gangue particles, such as the literature (Coal Preparation, 2003, 23: 13-20), uses a star-shaped discharger to continuously extract gangue above the gas distribution plate. For example, the literature (Journal of China Coal Society, 2014, 39(8):1565-1571) uses a scraper conveyor to continuously remove the gangue from the gas distribution plate.
[0005] However, these two methods that rely on mechanical equipment have the following disadvantages: 1) The sealing problem needs to be solved, otherwise air will leak from here, affecting the stable operation of the flotation bed; 2) The movement of mechanical equipment will be accompanied by noise pollution and wear problems, with a high failure rate and a short service life; 3) The movement of mechanical equipment will have a certain crushing effect on the gangue, produce fine powder, and aggravate the dust pollution problem; 4) The investment and operating costs of mechanical equipment are relatively high. Summary of the invention
[0006] In order to solve the above problems, the present invention provides a flotation bed for continuously mining gangue from raw coal, comprising a flotation bed body, a gangue outflow port for gangue to flow out of the flotation bed body by its own weight during flotation is arranged at the lower part of the flotation bed body, and a coal overflow port for coal to overflow out of the flotation bed body during flotation is arranged on the upper side wall of the flotation bed body;
[0007] The flotation bed body is provided with a gas distributor for continuously inputting gas into the flotation bed body and allowing gangue in the raw coal to be sorted to pass downward;
[0008] The lower part of the flotation bed body is filled with a material sealing particle layer for preventing gas from flowing downward during the flotation process, and a medium particle layer is arranged on the upper part of the material sealing layer particles;
[0009] The flotation bed body is provided with a feed port for introducing raw coal particles into the flotation bed body on the side wall of the upper part of the gas distributor.
[0010] The upper surface of the material sealing particle layer is slightly higher than the upper horizontal surface of the gas distributor.
[0011] On the basis of the above scheme, the particles used in the material seal particle layer are gangue particles generated in the process of raw coal sorting.
[0012] On the basis of the above solution, the gangue flow outlet is arranged on the bottom wall of the flotation bed body or the bottom side wall of the flotation bed body, and is located below the gas distributor.
[0013] Based on the above solution, the particles used in the medium particle layer are magnetite powder.
[0014] Based on the above solution, the gas flow rate input into the flotation bed body by the gas distributor is greater than the minimum fluidization velocity of the medium particles.
[0015] The present application also provides a method for continuously mining gangue from raw coal, comprising the following steps:
[0016] S1: close the gangue outlet at the bottom of the flotation bed body, and fill the flotation bed body with particles of a sealing particle layer for preventing gas from flowing downward during flotation, until the upper surface of the sealing particle layer is slightly higher than the upper horizontal surface of the gas distributor;
[0017] S2: adding the material of the medium particle layer (i.e., magnetite powder) to the upper part of the material seal particle layer until the material surface of the medium particle layer reaches the upper coal overflow port;
[0018] S3 introduces air into the flotation bed body through a gas distributor to stabilize the medium particles in the medium particle layer and fluidize them;
[0019] S4 continuously adds the crushed raw coal particles into the medium particle layer at the upper part of the gas distributor, and opens the gangue outlet at the same time;
[0020] S5 Coal particles with smaller density gradually float to the upper surface of the medium particle layer and continuously overflow from the coal overflow port;
[0021] The gangue particles with higher density gradually sink and pass through the gas distributor to become the upper particles of the material-sealed particle layer. At the same time, the particles at the bottom of the material-sealed particle layer continuously flow out from the gangue outlet by their own gravity.
[0022] On the basis of the above scheme, in step S5, the rate at which the gangue continuously flows out of the gangue flow outlet is equal to the feed rate of the gangue component continuously added to the raw coal particles in step S4.
[0023] On the basis of the above scheme, during the continuous mining of gangue in step S5, the interface between the seal particle layer and the medium particle layer is stabilized slightly above the gas distributor (slightly above means that the interface is slightly higher than the upper horizontal plane of the gas distributor, for example, within 10 mm higher).
[0024] The beneficial effects of the present invention are as follows: the flotation bed of the present invention does not involve mechanical moving parts in the process of continuously mining gangue, and there is no noise pollution and wear problem. The investment and operation cost of the flotation bed is low, the failure rate is low, and the service life is long; the mining process of gangue particles does not produce fine powder, which can reduce the dust pollution problem; a great advantage of the present invention is that the flotation bed simply relies on the accumulation of the gangue particles themselves to seal the material, thereby avoiding the problem of gas blowby; during the mining process, the gangue particles rely on their own gravity to flow out without the need for external force assistance. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 creative work.
[0026] Figure 1 This is a schematic diagram of the structure of the flotation bed in Example 1 of the present application;
[0027] Figure 2 This is a schematic diagram of the flotation process of the flotation bed in Example 2 of the present application;
[0028] Figure 3 This is a schematic diagram of the flotation process of the flotation bed in Application Example 2 of this application;
[0029] Figure 4 This is a schematic diagram of the enlarged structure of Part A in Example 1 of the present application. DETAILED DESCRIPTION
[0030] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0031] Example 1
[0032] like Figure 1 As shown, the present invention provides a flotation bed for continuously mining gangue from raw coal, comprising a flotation bed body 1, a gangue outflow port 1-1 for gangue to flow out of the flotation bed body 1 by its own weight during flotation is arranged at the lower part of the flotation bed body 1, and a coal overflow port 1-2 for coal to overflow out of the flotation bed body 1 during flotation is arranged on the upper side wall of the flotation bed body 1;
[0033] The flotation bed body 1 is provided with a gas distributor 2 for continuously inputting gas into the flotation bed body 1 and allowing gangue in the raw coal to be sorted to pass downward;
[0034] The lower part of the flotation bed body 1 is filled with a material sealing particle layer 3 for preventing gas from flowing downward during the flotation process, and the upper part of the material sealing particle layer 3 is provided with a medium particle layer 4;
[0035] The flotation bed body 1 is provided with a feed port 1 - 3 on the side wall of the upper part of the gas distributor 2 for introducing raw coal particles into the flotation bed body 1 .
[0036] The particles used in the above-mentioned material seal particle layer 3 are gangue particles generated during the raw coal sorting process.
[0037] like Figure 4 As shown, the upper surface of the material sealing particle layer 3 is slightly higher than the upper horizontal surface of the gas distributor 2. (Here, "slightly higher" means that the upper surface of the material sealing particle layer 3 just exceeds the upper horizontal surface of the gas distributor, for example, within 10 mm higher)
[0038] The gas distributor 2 may have many shapes, as long as it can achieve gas distribution and allow gangue particles to pass downward, for example, it may be in a ring shape, a grid shape, etc.
[0039] The gangue flow outlet 1 - 1 is arranged on the bottom wall of the flotation bed body 1 or the bottom side wall of the flotation bed body 1 , and is located below the gas distributor 2 .
[0040] The particles used in the medium particle layer 4 are magnetite powder.
[0041] Example 2
[0042] Based on the flotation bed for continuously mining gangue from raw coal in Example 1, the present application provides a method for continuously mining gangue from raw coal, comprising the following steps:
[0043] S1: close the gangue outlet 1-1 at the bottom of the flotation bed body 1, and fill the flotation bed body 1 with particles of the sealing particle layer 3 for preventing gas from flowing downward during the flotation process, until the upper surface of the sealing particle layer 3 is slightly higher than the upper horizontal surface of the gas distributor 2;
[0044] S2: adding the material of the medium particle layer 4 to the upper part of the material sealing particle layer 3 until the material surface of the medium particle layer 4 reaches the upper coal overflow port 1-2;
[0045] S3 introduces air into the flotation bed body 1 through the gas distributor 2 to stabilize the medium particles in the medium particle layer 4;
[0046] S4: continuously adding the crushed raw coal particles from the feed port 1-3 to the medium particle layer 4 on the upper part of the gas distributor 2, and simultaneously opening the gangue outlet 1-1;
[0047] S5 The coal particles with smaller density gradually float to the upper surface of the medium particle layer 4 and continuously overflow from the coal overflow port 1-2;
[0048] The gangue particles with higher density gradually sink and pass through the gas distributor 2 to become the upper particles of the material sealing particle layer 3. Meanwhile, the particles at the bottom of the material sealing particle layer 3 continuously flow out from the gangue outflow port 1-1 by their own gravity.
[0049] That is to say, at the beginning of flotation, the first particles to flow out from the gangue outflow outlet 1-1 are the particles of the loaded material sealing particle layer 3. As the flotation proceeds, the particles of the loaded material sealing particle layer 3 flow out first, and then the gangue particles after flotation flow out.
[0050] For the continuous and stable operation of the flotation bed, in step S5, the rate at which the gangue continuously flows out of the gangue outlet 1-1 is equal to the feed rate of the gangue component continuously added to the raw coal particles in step S4.
[0051] During the continuous extraction of gangue in step S5 , the interface between the seal particle layer 3 (actually the selected gangue) and the medium particle layer 4 is stabilized slightly above the upper horizontal surface of the gas distributor 2 .
[0052] In step S3, the speed of introducing air into the flotation bed body 1 through the gas distributor 2 is greater than the minimum fluidization speed of the medium particle layer 4, and after the gas is introduced, the density of the flotation bed layer is between the density of coal and the density of gangue.
[0053] Application Example 1
[0054] Based on the flotation bed in Example 1 and the flotation method in Example 2, the present application provides an application example of continuously mining gangue from raw coal.
[0055] like Figure 1 and 2 As shown, in this application example, the gas distributor 2 uses an annular gas distributor (the grid-type gas distributor can not only realize gas distribution, but also allow gangue to pass downward), and the medium particles of the medium particle layer 4 are selected from 60-100 mesh magnetite powder (the effective ingredient is Fe3O4), and the measured minimum fluidization velocity is 0.129m / s (this speed is the inherent property of 60-100 mesh magnetite powder).
[0056] First, the gangue flow outlet 1 - 1 at the bottom of the flotation bed is blocked, and then the gangue particles are loaded into the flotation bed to form a material-sealed particle layer 3 until the upper surface of the material-sealed particle layer 3 is slightly higher than the upper horizontal surface of the gas distributor 2 .
[0057] After that, add medium particles to the flotation bed body 1 until the material surface is flush with the lower edge of the coal overflow port 1-2. Then, introduce air into the flotation bed and adjust the air velocity to 0.150m / s to fluidize the magnetite powder (at this time, some magnetite will overflow from the coal overflow port 1-2 due to the expansion of the bed layer). After the fluidization state of the magnetite powder is stable, the raw coal particles (1-1.5mm) are continuously introduced from the middle of the flotation bed body 1 (above the gas distributor), and the gangue flow outlet 1-1 is opened at the same time. The lighter coal particles will gradually float to the surface of the magnetite powder bed and continuously overflow from the coal overflow port 1-2. The heavier gangue particles will gradually sink, pass through the gas distributor, and settle to the bottom of the flotation bed, and finally flow out from the gangue flow outlet 1-1 by their own gravity.
[0058] According to the feed rate of raw coal particles, the outflow rate of gangue particles is adjusted, and finally stable continuous operation can be achieved, that is, the interface between gangue and magnetite powder is stabilized slightly above the gas distributor. For the gangue flow outlet 1-1 set on the bottom wall, the outflow rate of gangue can be adjusted by changing the aperture and the depth of the outlet.
[0059] Application Example 2
[0060] Based on the flotation bed in Example 1 and the flotation method in Example 2, the present application provides another application example of continuously mining gangue from raw coal.
[0061] like Figure 3 As shown, this application example uses a grid-type gas distributor (the grid-type gas distributor can not only realize gas distribution, but also allow gangue to pass downward), the bed material particles (medium particles) are 60-100 mesh magnetite powder (the effective ingredient is Fe3O4), and the measured minimum fluidization velocity is 0.129m / s.
[0062] First, the gangue flow outlet 1 - 1 provided on the bottom side wall of the flotation bed is blocked, and then the gangue particles are loaded into the flotation bed to form a material-sealed particle layer 3 until the upper surface of the material-sealed particle layer 3 is slightly higher than the upper horizontal surface of the gas distributor 2 .
[0063] After that, add medium particles to the flotation bed body 1 until the material surface is flush with the lower edge of the coal overflow port 1-2. Then introduce fluidizing air into the flotation bed from the gas distributor, adjust the gas velocity to 0.150m / s, and fluidize the magnetite powder (some will overflow). After the fluidization reaches a steady state, the raw coal particles are continuously introduced from the middle of the flotation bed body 1 (above the gas distributor), and the gangue flow outlet 1-1 is opened at the same time. The lighter coal particles will gradually float to the surface of the magnetite powder bed and continuously overflow from the coal overflow port 1-2. The heavier gangue particles will gradually sink, pass through the gas distributor, and settle to the bottom of the flotation bed, and finally flow out from the gangue flow outlet 1-1 by their own gravity.
[0064] According to the feed rate of raw coal particles, the outflow rate of gangue particles is adjusted, and finally stable continuous operation can be achieved, that is, the interface between gangue and magnetite powder is stabilized slightly above the gas distributor. For the gangue outflow outlet 1-1 set on the bottom side wall, the outflow rate of gangue can be adjusted by changing the hole diameter, hole depth and vertical inclination angle.
[0065] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of protection of the present invention.
Claims
1. A flotation bed for continuously extracting gangue from raw coal, characterized in that: The flotation bed body (1) comprises a flotation bed body (1), wherein the lower part of the flotation bed body (1) is provided with a gangue outflow port (1-1) for gangue to flow out of the flotation bed body (1) by its own weight during flotation, and the upper side wall of the flotation bed body (1) is provided with a coal overflow port (1-2) for coal to overflow out of the flotation bed body (1) during flotation; The flotation bed body (1) is provided with a gas distributor (2) for continuously inputting gas into the interior of the flotation bed body (1) and allowing gangue in the raw coal to be separated to pass downward; The lower part of the flotation bed body (1) is filled with a material sealing particle layer (3) for preventing gas from flowing downward during the flotation process, and a medium particle layer (4) is arranged on the upper part of the material sealing layer particles (3); The flotation bed body (1) is provided with a feed port (1-3) on the side wall of the upper part of the gas distributor (2) for introducing raw coal particles into the flotation bed body (1).
2. The flotation bed for continuously extracting gangue from raw coal according to claim 1, characterized in that: The upper surface of the material sealing particle layer (3) is slightly higher than the upper horizontal surface of the gas distributor (2).
3. The flotation bed for continuously extracting gangue from raw coal according to claim 1, characterized in that: The particles used in the material sealing particle layer (3) are gangue particles generated during the raw coal sorting process.
4. The flotation bed for continuously extracting gangue from raw coal according to claim 1, characterized in that: The gangue flow outlet (1-1) is arranged on the bottom wall of the flotation bed body (1) or the bottom side wall of the flotation bed body (1), and is located below the gas distributor (2).
5. The flotation bed for continuously extracting gangue from raw coal according to claim 1, characterized in that: The particles used in the medium particle layer (4) are magnetite powder.
6. The flotation bed for continuously extracting gangue from raw coal according to claim 1, characterized in that: The gas flow rate inputted into the flotation bed body (1) by the gas distributor (2) is greater than the minimum fluidization velocity of the medium particles.
7. A method for continuously extracting gangue from raw coal, characterized in that: The steps include: S1: closing the gangue outlet (1-1) at the bottom of the flotation bed body (1), and loading particles of a sealing particle layer (3) for preventing gas from flowing downward during flotation into the flotation bed body (1), until the upper surface of the sealing particle layer (3) is slightly higher than the upper horizontal surface of the gas distributor (2); S2: adding particles used in the medium particle layer (4) to the upper part of the material sealing particle layer (3) until the material surface of the medium particle layer (4) reaches the upper coal overflow port (1-2); S3 introduces air into the flotation bed body (1) through the gas distributor (2) to stabilize the fluidization of the medium particles in the medium particle layer (4); S4: continuously adding the crushed raw coal particles from the raw coal feed port (1-3) into the medium particle layer (4) on the upper part of the gas distributor (2), and simultaneously opening the gangue flow outlet (1-1); S5 Coal particles with a smaller density gradually float to the upper surface of the medium particle layer (4) and continuously overflow from the coal overflow port (1-2); Gangue particles with a larger density gradually sink and pass through the gas distributor (2) to become upper particles of the material sealing particle layer (3). At the same time, the gangue particles at the bottom of the material sealing particle layer (3) continuously flow out from the gangue flow outlet (1-1) by their own gravity.
8. The method for continuously mining gangue from raw coal according to claim 7, characterized in that: In step S5, the rate at which the gangue continuously flows out of the gangue outflow port (1-1) is equal to the feed rate of the gangue component continuously added to the raw coal particles in step S4.
9. The method for continuously mining gangue from raw coal according to claim 7, characterized in that: During the continuous mining of gangue in step S5, the interface between the seal particle layer (3) and the medium particle layer (4) is stabilized slightly above the upper horizontal plane of the gas distributor (2).
10. The method for continuously mining gangue from raw coal according to claim 7, characterized in that: In step S3, the speed of introducing air into the flotation bed body (1) through the gas distributor (2) is greater than the minimum fluidization speed of the medium particle layer (4), and after the gas is introduced, the density of the flotation bed layer is between the density of coal and the density of gangue.
Citation Information
Patent Citations
Coal dry flotation process
CN116351706A