Whole-fraction dry-wet combined separation method for coal
Through the coal-wide wet and dry sorting method, the composite dry sorting machine and heavy-medium shallow tank sorting are used to solve the problem of low efficiency of the traditional coal washing and selection process, and efficient and low-cost coal sorting is achieved, and the sorting efficiency and product quality are improved.
Patent Information
- Application Number
- CN202510715509.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-30
- Publication Date
- 2025-07-11
AI Technical Summary
The traditional coal washing and selection process is low efficiency and high cost, making it difficult to meet the needs of modern green and low-carbon industrial production. There are problems such as poor regulation flexibility, serious product mismatch, easy to mix high-density gangue particles into refined coal products, and reducing calorific output.
The coal-wide wet and dry sorting method is adopted, including first-grade screening, composite dry sorting machine sorting, heavy-medium shallow trough sorting and second-grade screening. Through efficient composite dry sorting machine and heavy-medium shallow trough sorting, the whole-grade washing of raw coal is achieved, the product moisture and ash content is reduced, and the sorting efficiency and heat generation are improved.
It improves the applicability of coal sorting, reduces production costs, increases product economic benefits, and realizes efficient sorting of full-grain grade raw coal washing operations.
Smart Images
Figure CN120286174A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of coal separation, and particularly to a method for dry-wet combined separation of coal with all particle sizes. Background Art
[0002] As an important industrial production energy source in China, coal plays an important role in the process of national economic development and modernization construction. For a quite long period in the future, coal will still be the main energy source in China, serving as the ballast and stabilizer for China's energy security. Coal washing operations can effectively remove the gangue minerals and harmful elements mixed in it, which is the source technology for clean coal and can effectively improve the ecological environment quality and increase the calorific value of coal. Therefore, coal washing is of great strategic significance for China to give full play to its coal resource advantages, ensure energy security, and protect the ecological environment.
[0003] However, problems such as low efficiency and high cost of the single traditional main coal washing process are becoming increasingly prominent, making it difficult to meet the requirements of modern green and low-carbon industrial production. Especially with the fluctuation of raw coal quality, the traditional coal washing production process has problems such as poor adjustment flexibility, serious product mismatch that easily causes the loss of some clean coal products, easy mixing of high-density gangue particles in clean coal products, thus reducing the calorific value of clean coal products, and poor ash and sulfur reduction effects of coal, seriously restricting the clean, efficient separation, processing and utilization of coal. Therefore, developing a new way of coal washing process that is simple, flexible and reliable and can effectively improve the quality of coal with wide particle sizes is one of the important measures to improve economic and ecological benefits. Summary of the Invention
[0004] The present invention aims to solve at least one of the technical problems in the related technologies to some extent. For this reason, the first object of the present invention is to propose a method for dry-wet combined separation of coal with all particle sizes, which uses an efficient compound dry separator to separate raw coal, reduces the product moisture, improves the applicability of coal separation, and obtains clean coal, gangue and middling products; performs heavy medium shallow trough separation on the large lump raw coal and the middling products of the compound dry separator, which can effectively reduce the ash and sulfur content of the products, improve the separation efficiency, calorific value and recovery rate of the products, reduce the production cost, and increase the economic benefits of the products; adopts a dry-wet combined separation process, which complements each other's advantages and can effectively realize the washing operation of raw coal with all particle sizes.
[0005] To achieve the above object, an embodiment of the first aspect of the present invention provides a method for dry-wet combined separation of coal with all particle sizes, comprising: screening and classifying raw coal with all particle sizes through a first sizing screen for the first-stage screening and classification to obtain oversize materials of the first stage and undersize materials of the first stage; separating the undersize materials of the first stage by using a compound dry separator to obtain first-stage clean coal, first-stage gangue and middling products; re-separating the middling products and the oversize materials of the first stage through a heavy medium shallow trough to obtain second-stage clean coal and second-stage gangue; and screening and classifying the first-stage clean coal and the second-stage clean coal through a second sizing screen for the second-stage screening and classification to obtain lump clean coal and fine clean coal.
[0006] According to the method for dry-wet combined separation of coal with all particle sizes of the embodiment of the present invention, first, raw coal with all particle sizes is screened and classified through a first sizing screen for the first-stage screening and classification to obtain oversize materials of the first stage and undersize materials of the first stage. Then, the undersize materials of the first stage are separated by using a compound dry separator to obtain first-stage clean coal, first-stage gangue and middling products. Next, the middling products and the oversize materials of the first stage are re-separated through a heavy medium shallow trough to obtain second-stage clean coal and second-stage gangue. Finally, the first-stage clean coal and the second-stage clean coal are screened and classified through a second sizing screen for the second-stage screening and classification to obtain lump clean coal and fine clean coal. Thus, the method uses an efficient compound dry separator to separate raw coal, reduces the moisture content of products, improves the applicability of coal separation, and obtains clean coal, gangue and middling products; performing heavy medium shallow trough separation on large lump raw coal and the middling products of the compound dry separator can effectively reduce the ash content and sulfur content of products, improve the separation efficiency, calorific value and recovery rate of products, reduce production costs, and increase the economic benefits of products; adopting a dry-wet combined separation process, with complementary advantages, can effectively realize the washing operation of raw coal with all particle sizes.
[0007] In addition, according to the method for dry-wet combined separation of coal with all particle sizes of the above embodiment of the present invention, the following additional technical features may also be provided:
[0008] According to an embodiment of the present invention, the particle size range of the raw coal with all particle sizes is 300 - 0 mm.
[0009] According to an embodiment of the present invention, the aperture of the first sizing screen is 100 mm.
[0010] According to an embodiment of the present invention, the processing capacity of the compound dry separator is 60 - 100 t / h.
[0011] According to an embodiment of the present invention, the external moisture of the first-stage clean coal separated by the compound dry separator is less than 5%.
[0012] According to an embodiment of the present invention, before re-separating the middling products and the oversize materials of the first stage through a heavy medium shallow trough, the middling products and the oversize materials of the first stage are simultaneously fed into a buffer bin for mixing.
[0013] According to an embodiment of the present invention, the throughput of the heavy medium shallow tank is ≥ 100 t / h.
[0014] According to an embodiment of the present invention, the middling product and the oversize material of the first stage are re-separated through the heavy medium shallow tank, including: after mixing the middling product and the oversize material of the first stage, entering the heavy medium shallow tank.
[0015] According to an embodiment of the present invention, the screen holes of the second sizing screen are one of 50 mm, 30 mm, 13 mm and 6 mm.
[0016] According to an embodiment of the present invention, during the classification and separation process, a bag filter is used to collect 3 - 0 mm dust.
[0017] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings
[0018] Figure 1 It is a flowchart of the coal full - size dry - wet combined separation method according to an embodiment of the present invention;
[0019] Figure 2 It is a process flowchart of the coal full - size dry - wet combined separation method according to an embodiment of the present invention. Detailed Embodiments
[0020] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.
[0021] The coal full - size dry - wet combined separation method proposed by the embodiments of the present invention will be described below with reference to the drawings.
[0022] Figure 1 It is a flowchart of the coal full - size dry - wet combined separation method according to an embodiment of the present invention.
[0023] As Figure 1 shown, the coal full - size dry - wet combined separation method of the embodiments of the present invention may include the following steps:
[0024] S1, subjecting the full - size raw coal to the first - stage screening classification through the first sizing screen to obtain the oversize material of the first stage and the undersize material of the first stage.
[0025] According to an embodiment of the present invention, the particle size range of the full - size raw coal is 300 - 0 mm.
[0026] S2. Subject the oversize material from the first screening to separation using a compound dry separator to obtain first-stage clean coal, first-stage gangue, and middlings products.
[0027] S3. Subject the middlings products and the oversize material from the first screening to re-separation in a heavy medium shallow trough to obtain second-stage clean coal and second-stage gangue.
[0028] S4. Subject the first-stage clean coal and the second-stage clean coal to a second screening and classification using a second sizing screen to obtain lump clean coal and fine clean coal.
[0029] Specifically, as Figure 2 shown, first crush the raw coal larger than 300 mm in the coal bunker to obtain raw coal with a full particle size range of 300 - 0 mm, and then transport it to the first sizing screen through a belt conveyor for the first screening and classification to obtain the oversize material and the undersize material from the first screening. The particle size range of the undersize material from the first screening is suitable for the compound dry separator. The compound dry separator uses an air distribution plate to evenly distribute the compressed air flow on the bed surface, and the coupled action of the air flow and the bed vibration is applied to the undersize material from the first screening to promote its fluidization, thereby realizing the segregation of the undersize material from the first screening to obtain first-stage clean coal, first-stage gangue, and middlings products. The compound dry separator has high separation accuracy, and no water is used in the separation process. The first-stage clean coal after separation has low moisture content and high calorific value.
[0030] Furthermore, the ash content of the middlings products of the compound dry separator is relatively high. To further remove the ash and sulfur in the middlings products and enhance their added value, the middlings products are fed into the heavy medium shallow trough together with the oversize material from the first screening for re-separation to obtain second-stage clean coal and second-stage gangue. Among them, the heavy medium shallow trough can effectively separate large raw coal blocks larger than 100 mm, has a large throughput, high separation accuracy, and can simultaneously remove the gangue in the middlings products, reduce the ash content of the middlings products, and increase the calorific value.
[0031] Then, according to the needs of different customers, subject the first-stage clean coal and the second-stage clean coal to a second screening and classification using a second sizing screen to obtain lump clean coal and fine clean coal.
[0032] Thus, the full particle size dry-wet combined separation method for coal in the embodiment of the present invention uses an efficient compound dry separator to separate the raw coal, reduces the product moisture, improves the applicability of coal separation, and obtains clean coal, gangue, and middlings products; subject the large raw coal blocks and the middlings products of the compound dry separator to heavy medium shallow trough separation, which can effectively reduce the ash and sulfur of the products, improve the separation efficiency, calorific value, and recovery rate of the products, reduce the production cost, and increase the economic benefits of the products; adopt the dry-wet combined separation process, which complements each other's advantages, and can effectively realize the full particle size washing operation of the raw coal.
[0033] According to an embodiment of the present invention, the aperture of the first sizing screen is 100 mm. The raw coal particles smaller than 100 mm are suitable for treatment by the compound dry separator.
[0034] According to an embodiment of the present invention, the processing capacity of the compound dry separator is 60 - 100 t / h.
[0035] According to an embodiment of the present invention, the external water content of the first-stage clean coal separated by the compound dry separator is less than 5%.
[0036] Specifically, the compound dry separator uses an air distribution plate to evenly distribute the compressed air flow on the bed surface. The coupling effect of the air flow and the bed surface vibration is applied to the material under the first-stage screen, promoting its fluidization, and then realizing the segregation of the material under the first-stage screen, obtaining the first-stage clean coal, the first-stage gangue, and the middling products. The compound dry separator has high separation accuracy, and water is not used in the separation process. The first-stage clean coal after separation has low moisture content and high calorific value. The compound dry separator has the characteristics of not using water for separation, simple process, few equipment, low production cost, and low energy consumption. It is suitable for coal gangue removal and coal preparation in arid and water-deficient areas, can effectively reduce the washing and processing cost, and improve the automation level of the equipment.
[0037] According to an embodiment of the present invention, before the middling products and the material on the first-stage screen are re-separated by a dense medium shallow trough, the middling products and the material on the first-stage screen are simultaneously fed into a buffer bin for mixing.
[0038] According to an embodiment of the present invention, the processing capacity of the dense medium shallow trough is ≥ 100 t / h.
[0039] According to an embodiment of the present invention, re-separating the middling products and the material on the first-stage screen by a dense medium shallow trough includes: after mixing the middling products and the material on the first-stage screen, then entering the dense medium shallow trough.
[0040] Specifically, after mixing the middling products and the material on the first-stage screen, then entering the dense medium shallow trough for re-separation. The dense medium shallow trough separator mainly relies on Archimedes' principle. The dense medium suspension within a certain density range is input into the separation trough in the form of upward flow and horizontal flow through a slurry pump. The materials are automatically stratified in the trough according to the density difference. The light products (clean coal) float and are discharged with the horizontal flow, and the heavy products (gangue, etc.) sink and are discharged by a scraper, obtaining the second-stage clean coal and the second-stage gangue. Among them, the dense medium shallow trough can effectively separate large-sized raw coal larger than 100 mm, has a large processing capacity, high separation accuracy, and can simultaneously remove the gangue in the middling products, reduce the ash content of the middling products, and increase the calorific value.
[0041] According to an embodiment of the present invention, the screen holes of the second grading screen are one of 50 mm, 30 mm, 13 mm, and 6 mm. Thus, clean coal with different particle size ranges can be obtained according to different customer requirements.
[0042] According to an embodiment of the present invention, during the grading and separation process, a bag filter is used to collect 3 - 0 mm dust. The bag filter can collect the 3 - 0 mm dust generated during the separation process to prevent dust from polluting the air.
[0043] In this embodiment, raw coal larger than 300 mm in the raw coal bunker is crushed and transported to a sizing screen by a belt conveyor. The raw coal with a full particle size range of 300 - 0 mm is subjected to the first-stage screening and classification. Specifically, the screen hole diameter of the raw coal sizing screen of the present invention is 100 mm. The particle size range of the undersize material after the raw coal is classified is suitable for a compound dry separator. The processing capacity of the compound dry separator is 60 - 100 t / h. A air distribution plate is used to evenly distribute the compressed air flow on the bed surface. The coupling effect of the air flow and the bed surface vibration is applied to the coal particles to promote their fluidization, and then the segregation of the raw coal particles is realized, obtaining clean coal, medium coal, and gangue products. The separation accuracy is high, and no water is used in the separation process. The moisture content of the clean coal after separation is low and the calorific value is high. During the separation process, a bag filter is used to collect the dust with a particle size of 3 - 0 mm.
[0044] The ash content of the medium coal product of the compound dry separator is relatively high. To further remove the ash and sulfur in the medium coal product and improve its added value, it is fed into a buffer bin together with the oversize raw coal from the first-stage sizing screen. After mixing, it is transported to a heavy medium shallow trough for re-separation. Under the disturbance of the upward flow and the horizontal flow, the coal is stratified and segregated, obtaining second-stage clean coal and gangue products. Among them, the processing capacity of the heavy medium shallow trough is ≥100 t / h. The heavy medium shallow trough can effectively separate the +100 mm large lump raw coal, has a large processing capacity and high separation accuracy, and can simultaneously remove the gangue in the medium coal product, reduce the ash content of the medium coal product, and increase the calorific value.
[0045] According to the needs of different customers, the first-stage clean coal product or the second-stage clean coal product is transported to a second-stage sizing screen. Specifically, the screen holes of the second-stage sizing screen are 50 mm or 30 mm or 13 mm or 6 mm. After screening, third-stage fast clean coal and fine clean coal with different particle sizes can be obtained.
[0046] The full particle size dry-wet combined coal separation method provided by the present invention, on the one hand, the application of the heavy medium shallow trough solves the technical bottleneck of the compound dry separator for processing large lump raw coal. On the other hand, the medium coal re-selection process method makes up for the defect of the relatively high ash content in the medium coal of the compound dry separator. Correspondingly, compared with the heavy medium shallow trough, the compound dry separator has a simple structure, low operating power consumption, lower moisture content of its clean coal product, and higher calorific value. Using it as the main washing equipment has better economic and environmental benefits.
[0047] In summary, according to the dry-wet combined separation method for all grain sizes of coal in the embodiments of the present invention, first, the all-grain-size raw coal is subjected to the first-stage screening and classification by the first grading screen to obtain the oversize material of the first stage and the undersize material of the first stage. Then, the undersize material of the first stage is separated by a compound dry separator to obtain the first-stage clean coal, the first-stage gangue, and the middling product. Next, the middling product and the oversize material of the first stage are re-separated by a dense medium shallow tank to obtain the second-stage clean coal and the second-stage gangue. Finally, the first-stage clean coal and the second-stage clean coal are subjected to the second-stage screening and classification by the second grading screen to obtain the lump clean coal and the fine clean coal. Thus, this method uses an efficient compound dry separator to separate the raw coal, reduces the moisture content of the product, improves the applicability of coal separation, and obtains clean coal, gangue, and middling products; separating the large-size raw coal and the middling product of the compound dry separator by a dense medium shallow tank can effectively reduce the ash content and sulfur content of the product, improve the separation efficiency, the calorific value of the product, and the recovery rate, reduce the production cost, and increase the economic benefits of the product; adopting the dry-wet combined separation process, with complementary advantages, can effectively realize the all-grain-size washing operation of the raw coal.
[0048] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.
Claims
1. A dry-wet combined separation method for all coal particle sizes, characterized in that Including: Performing first-stage screening and classification on the whole-sized raw coal through a first classification screen to obtain oversize materials and undersize materials of the first stage; Performing separation on the undersize materials of the first stage by using a compound dry separator to obtain first-stage clean coal, first-stage gangue and middlings products; Performing re-separation on the middlings products and the oversize materials of the first stage through a heavy-medium shallow trough to obtain second-stage clean coal and second-stage gangue; Performing second-stage screening and classification on the first-stage clean coal and the second-stage clean coal through a second classification screen to obtain lump clean coal and fine clean coal.
2. The full - size dry - wet combined coal separation method according to claim 1, characterized in that, The particle size range of the whole-sized raw coal is 300 - 0 mm.
3. The coal full-size wet-dry combined separation method according to claim 1, characterized in that, The aperture of the first classification screen is 100 mm.
4. The full-size wet-dry combined coal separation method according to claim 1, wherein The processing capacity of the compound dry separator is 60 - 100 t / h.
5. The coal full-size wet-dry combined separation method according to claim 1, characterized in that, The external moisture of the first-stage clean coal separated by the compound dry separator is lower than 5%.
6. The dry-wet combined separation method for all particle sizes of coal according to claim 1, characterized in that Before performing re-separation on the middlings products and the oversize materials of the first stage through a heavy-medium shallow trough, feeding the middlings products and the oversize materials of the first stage into a buffer bin simultaneously for mixing.
7. The coal full-size dry-wet combined separation method according to claim 1, wherein The processing capacity of the heavy-medium shallow trough is ≥100 t / h.
8. The coal full-size dry-wet combined separation method according to claim 1, characterized in that Performing re-separation on the middlings products and the oversize materials of the first stage through a heavy-medium shallow trough, including: After mixing the middlings products and the oversize materials of the first stage, feeding them into the heavy-medium shallow trough.
9. The coal full-size wet-dry combined separation method according to claim 1, wherein The screen holes of the second classification screen are one of 50 mm, 30 mm, 13 mm and 6 mm.
10. The coal full - size dry - wet combined separation method according to claim 1, characterized in that, During the classification and separation process, collecting 3 - 0 mm dust by using a bag filter.