Abstract
A clean coal production system and method for treating coal refuse (waste) resulted from coal mining or coal washing plants by extracting substantial remaining coal components from said coal refuse (waste) and turning them into clean (fine) coal products of much higher market value wherein the necessary water usage is recovered, recycled, and reused in a closed setting (ecosystem) to minimize environmental concerns.
Claims
1. A system of clean coal production from coal refuse waste comprising: a screen series, a cyclone separator series, a floating selection separator series, and a presser-filter series.
2. The system of claim 1, wherein the screen series comprising: a coarse sieve, a de-soiling sieve, a fine coal sieve, a coal middlings sieve, and a coal gangue sieve.
3. The system of claim 2, wherein the cyclone separator series comprising: a first cyclone separator, and a second cyclone separator.
4. The system of claim 3, wherein the floating selection separator series comprising: a first floating selection separator, a second floating selection separator, and a third floating selection separator.
5. The system of claim 4, wherein the presser-filter series comprising: a coal tailings presser-filter, a clean coal presser-filter, and a coal middlings presser-filter.
6. A system of clean coal production from coal refuse waste coupled with coal washing plants comprising: a screen series, a cyclone separator series, a floating selection separator series, and a presser-filter series.
7. The system of claim 6, wherein the screen series comprising: a classification sieve, a coarse sieve, a de-soiling sieve, a fine coal sieve, a coal middlings sieve, and a coal gangue sieve.
8. The system of claim 6, wherein the cyclone separator series comprising: a first cyclone separator, and a second cyclone separator.
9. The system of claim 6, wherein the floating selection separator series comprising: a first floating selection separator, a second floating selection separator, and a third floating selection separator.
10. The system of claim 6, wherein the presser-filter series comprising: a coal tailings presser-filter, a clean coal presser-filter, and a coal middlings presser-filter.
11. A method of clean coal production from coal refuse waste comprising performing steps of: (1). series screening treatment step, (2). series cyclone separation treatment step, (3). series floating selection separation treatment step, and (4). series presser-filter treatment step.
12. The method of claim 11, wherein the series screening treatment step comprising the use of: a coarse sieve, a de-soiling sieve, a fine coal sieve, a coal middlings sieve, and a coal gangue sieve.
13. The method of claim 11, wherein the series cyclone separation treatment step comprising the use of: a first cyclone separator, and a second cyclone separator.
14. The method of claim 11, wherein the series floating selection separation treatment step comprising the use of: a first floating selection separator, a second floating selection separator, and a third floating selection separator.
15. The method of claim 11, wherein the series presser-filter treatment step comprising the use of: a coal tailings presser-filter, a clean coal presser-filter, and a coal middlings presser-filter.
16. The method of claim 11, wherein the series screening treatment step comprising the use of: a classification sieve, a coarse sieve, a de-soiling sieve, a fine coal sieve, a coal middlings sieve, and a coal gangue sieve.
17. The method of claim 16, wherein the series cyclone separation treatment step comprising the use of: a first cyclone separator, and a second cyclone separator.
18. The method of claim 16, wherein the series floating selection separation treatment step comprising the use of: a first floating selection separator, a second floating selection separator, and a third floating selection separator.
19. The method of claim 16, wherein the series presser-filter treatment step comprising the use of: a coal tailings presser-filter, a clean coal presser-filter, and a coal middlings presser-filter.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The particular features, characteristics, and advantages of the provided disclosures for the present invention as well as other objects will become apparent from the following descriptions in connection with the accompanying drawings in which:
[0016] FIG. 1 is a flowchart diagram illustrating an exemplary engineered portion for preliminary selecting and screening coal from coal refuse waste generated by coal mining or coal washing according to the disclosed invention.
[0017] FIG. 2 is a flowchart diagram illustrating an exemplary engineered portion for a first cyclone separator of coal from coal refuse waste generated by coal washing according to the disclosed invention.
[0018] FIG. 3 is a flowchart diagram illustrating an exemplary engineered portion for repetitive selecting and screening of coal middlings produced by the first cyclone separator according to the disclosed invention. This repetitive selecting and screening process continues until the treatment for a given batch of starting materials from FIG. 1 (Flowchart I) have been finished.
[0019] FIG. 4 is a flowchart diagram illustrating an exemplary engineered portion for collecting and harvesting clean (fine) coal according to the disclosed invention.
[0020] FIG. 5 is a flowchart diagram illustrating an exemplary engineered portion for a second cyclone separator of coal gangue that is generated from the first cyclone separator according to the disclosed invention.
[0021] FIG. 6 is a flowchart diagram illustrating an exemplary engineered portion for repetitive selecting and screening treatment of coal middlings produced by the second cyclone separator according to the disclosed invention. This repetitive selecting and screening process continues until the treatment for a given batch of starting materials from FIG. 1 (Flowchart I) have been finished.
[0022] FIG. 7 is a flowchart diagram illustrating an exemplary engineered portion for collecting and harvesting coal middlings and recovering water from coal tailings according to the disclosed invention.
[0023] FIG. 8 is a flowchart diagram illustrating an exemplary engineered portion for separating water from coal gangue and coal tailings according to the disclosed invention.
[0024] FIG. 9 is a flowchart diagram illustrating an exemplary engineered portion for a first floating selection separator according to the disclosed invention.
[0025] FIG. 10 is a flowchart diagram illustrating an exemplary engineered portion for a second floating selection separator according to the disclosed invention.
[0026] FIG. 11 is a flowchart diagram illustrating an exemplary engineered portion for a third (coal middlings) floating selection separator to produce coal middlings and recover water according to the disclosed invention.
[0027] FIG. 12 is a flowchart diagram illustrating an exemplary engineered portion for water recover, recycle, and reuse in a closed setting (ecosystem) according to the disclosed invention.
[0028] FIG. 13 is a flowchart diagram illustrating an exemplary engineered portion for coupling the presently disclosed invention with a coal washing or coal processing plant.
[0029] FIG. 14—Schematic Diagram of Present Invention Coupled with Coal Washing Plant.
[0030] FIG. 15—Schematic Diagram of Present Invention.
[0031] Particular screen or sieve series, cyclone separator series, floating selection separator series, and presser-filter series, their combinations and sequence ordering arrangements, are meant to be illustration or exemplary purposes, but not as restrictions or limitations thereof.
DETAILED DESCRIPTION
[0032] The embodiments described herein are not intended to limit the scope of the invention to the precise form disclosed. Rather, the embodiments described herein have been chosen and described to explain the principles of the invention and their applications and practical uses to best enable others skilled in the art to follow the disclosed teachings.
[0033] Referring to FIG. 1 (Flowchart I), a diagram illustrating an exemplary engineered portion for preliminary selecting and screening coal according to the disclosed invention from coal refuse waste generated by coal mining or coal washing. Specifically, coal silt (slime) refuse waste resulted from traditional coalmines or coal washing plants, or coal preparation and processing factories are collected for extracting clean (fine) coal product by the present invention disclosed herein. First, the coal silt (slime) refuse waste are mixed with sufficient amount of water in a mixing pool to form a slurry mixture. Then, the resulted slurry mixture of coal silt (slime) refuse waste and water are fed through a crusher to crush larger pieces, if any, therein and to improve the slurry mixture's consistency. The crusher-treated slurry mixture are loaded onto a coarse sieve. Coarse impurities such as large rock pieces (e.g., plus mesh material) on top of the coarse sieve are discarded as waste. Undersieves (e.g., minus mesh) material resulted from passing through the coarse sieve are subject to a de-soiling sieve. The plus mesh material that is produced from the de-soiling sieve shall follow FIG. 2 (Flowchart II-1) below for further treatment, while undersieves (e.g., minus mesh) material resulted from the de-soiling sieve shall go to FIG. 9 (Flowchart IX-1) below for further treatment.
[0034] Referring to FIG. 2 (Flowchart II), a diagram illustrating an exemplary engineered portion for a first cyclone separator of coal from coal refuse waste generated by coal mining or coal washing according to the disclosed invention. Specifically, the de-soiling sieve produced plus mesh material from FIG. 1 (Flowchart I-6) above are mixed with water in a holding pool for de-soiled material. Then, a feeding pump designated for the first cyclone separator pumps the de-soiled material in the holding pool into the first cyclone separator. The first cyclone separator separates the de-soiled material into the followings:
[0035] (a). coal middlings (middle coal), which shall follow FIG. 3 (Flowchart III-1) below,
[0036] (b). clean (fine) coal, which shall follow FIG. 4 (Flowchart IV-1) below, and
[0037] (c). coal gangue, which shall follow FIG. 5 (Flowchart V-1) below.
[0038] Referring to FIG. 3 (Flowchart III), a diagram illustrating an exemplary engineered portion for repetitive selecting and screening of coal middlings produced by the first cyclone separator according to the disclosed invention. Specifically, the coal middlings (middle coal) generated from the first cyclone separator as shown in FIG. 2 (Flowchart II-4a) above flows into a holding pool for de-soiled material, which is pumped back into the first cyclone separator repeatedly as shown in Flowchart II-2 above. This repetitive selecting and screening process continues until the treatment for a given batch of starting materials from FIG. 1 (Flowchart I) have been finished.
[0039] Referring to FIG. 4 (Flowchart IV), a diagram illustrating an exemplary engineered portion for collecting and harvesting clean (fine) coal according to the disclosed invention. Specifically, the clean (fine) coal from FIG. 3 (Flowchart III-4b) described above is subject to a fine coal sieve. Thus resulted plus mesh material from the fine coal sieve is clean (fine) coal, which is harvested as final product, while thus resulted undersieves (minus mesh) material passing through the fine coal sieve flows into a de-soiled water pool, which is pumped by a feeding pump for a first floating selection separator into the first floating selection separator, via a pre-treatment tank, as shown in FIG. 9 (Flowchart IX-3) below.
[0040] Referring to FIG. 5 (Flowchart V), a diagram illustrating an exemplary engineered portion for a second cyclone separator of coal gangue resulted from the first cyclone separator according to the disclosed invention. Specifically, the coal gangue from FIG. 2 (Flowchart II-4c) above flows into a coal middlings and coal gangue holding pool, from where pumped by a feeding pump for the second cyclone separator into the second cyclone separator. The second cyclone separator separates the mixture of coal middlings and coal gangue into the followings:
[0041] (a). coal middlings (middle coal), which shall follow FIG. 6 (Flowchart VI) below,
[0042] (b). neutral coal middlings, which shall follow FIG. 7 (Flowchart VII) below, and
[0043] (c). coal gangue, which shall follow FIG. 8 (Flowchart VIII) below.
[0044] Referring to FIG. 6 (Flowchart VI), a diagram illustrating an exemplary engineered portion for repetitive selecting and screening processing the coal middlings produced by the second cyclone separator according to the disclosed invention. Specifically, the coal middlings (middle coal) from FIG. 5 (Flowchart V-4a) above flow into a coal middlings and coal gangue holding pool as shown in FIG. 5 (Flowchart V-20) above and repeat the separation treatment by the second cyclone separator for the coal middlings generated by the second cyclone separator from the immediately prior step. This repetitive selecting and screening process continues until the treatment for a given batch of starting materials from FIG. 1 (Flowchart I) have been finished.
[0045] Referring to FIG. 7 (Flowchart VII), a diagram illustrating an exemplary engineered portion for collecting and harvesting coal middlings and separating water from tailings according to the disclosed invention. Specifically, the neutral coal middlings from FIG. 5 (Flowchart V-4b) above are subject to a neutral coal middlings sieve. The plus mesh material resulted from the neutral coal middlings sieve is harvested as coal middlings product, while the minus mesh material resulted from the neutral coal middlings sieve flows into a concentration pool, from where pumped by a feeding pump into a coal tailings presser-filter. From the coal tailings presser-filter, coal tailings as the final waste, are discarded or used as road paving or brick-making materials, while the recovered water that passed through the coal tailings presser-filter is recycled and reused, which flows into a water sedimentation and clearing pool as shown in FIG. 9 (Flowchart IX) below.
[0046] Referring to FIG. 8 (Flowchart VIII), a diagram illustrating an exemplary engineered portion for separating water from coal gangue and coal tailings according to the disclosed invention. Specifically, the coal gangue resulted from FIG. 5 (Flowchart V-4c) above is subject to a coal gangue sieve. Thus resulted plus mesh material is the final coal gangue as waste to be discarded, while thus resulted minus mesh material flows into a concentration pool, from where pumped by a feeding pump into the coal tailings presser-filter. Resulted material by the coal tailings presser-filter is coal tailings (tail coal) as final waste to be discarded or used as road paving martial or as brick-making material. The recovered water passed-through the coal tailings presser-filter is recycled and reused which flows into the water sedimentation and clearing pool as shown in FIG. 9 (Flowchart IX) below.
[0047] Referring to FIG. 9 (Flowchart IX), a diagram illustrating an exemplary engineered portion for the first floating selection separator according to the disclosed invention. Specifically, the undersieves (minus mesh) material resulted from the de-soiling sieve of FIG. 1 (Flowchart I-7) above flows into a de-soiled water pool and mixed with the minus mesh material resulted from the fine coal sieve after the first cyclone separator as shown in FIG. 4 (Flowchart IV-3 above) and a back-floating portion from a second floating selection separator shown in FIG. 10 (Flowchart X-4) below. From the de-soiled water pool, the mixture is pumped by a feeding pump for the first floating selection separator, via a pre-treatment tank, wherein mixing and controlling foaming take place. From the pre-treatment tank, the mixture flows into the first floating selection separator. From the first floating selection separator, resulting (a) a front floating portion that flows into the second floating selection separator, which shall follow FIG. 10 (Flowchart X) below; and (b) a back-floating portion that flows into a third (coal middlings) floating selection separator, which shall follow FIG. 11 (Flowchart XI) below.
[0048] Referring to FIG. 10 (Flowchart X), a diagram illustrating an exemplary engineered portion for the second floating selection separator according to the disclosed invention. Specifically, a front-floating portion from the first floating selection separator, as shown in FIG. 9 (Flowchart IX-4a) above, flows into the second floating selection separator. Then, a front-floating portion from the second floating selection separator flows into a clean coal pool, from which it is pumped into a clean coal presser-filter for making final clean coal product. Recovered water that passed through the clean coal presser-filter is recycled and reused, which flows into a water sedimentation and clearing pool as shown in FIG. 11 (Flowchart XI) below. A back-floating portion from the second floating selection separator flows into a de-soiled water pool as shown in FIGS. 4 and 9 (Flowcharts IV-4 and IX-2) above.
[0049] Referring to FIG. 11 (Flowchart XI), a diagram illustrating an exemplary engineered portion for the third (coal middlings) floating selection separator to produce coal middlings and recover water according to the disclosed invention. Specifically, a front-floating portion from the third (coal middlings) floating selection separator, as shown in FIG. 9 (Flowchart IX-4b) above, flows into a coal middlings pool, from where pumped into a coal middlings presser-filter to produce coal middlings as final product. A back-floating portion of the same third (coal middlings) floating selection separator flows into a concentration pool and is pumped by a feeding pump, as shown in FIG. 8 (Flowchart VIII-5 above) into a coal tailings presser-filter. The coal tailings presser-filter produces coal tailings (tail coal) as the final waste that is discarded or used as road paving martial or as brick-making material. Recovered water that passed through the coal tailings presser-filter flows into a water sedimentation and clearing pool and is recycled and reused.
[0050] Referring to FIG. 12 (Flowchart XII), a diagram illustrating an exemplary engineered portion for water recycle and reuse according to the disclosed invention. Specifically, all recovered water passed through from the presser-filters shown in FIGS. 7, 8, 9, 10, and 11 (Flowcharts VII-6, VIII-6, IX-3, X-3, and XI-4) above flows into a sedimentation and clearing pool, from which the recovered water then flows into or is pumped back into a mixing pool as shown in FIG. 1 (Flowchart I-2) above or used to replenish various holding pools as needed.
[0051] Referring to FIG. 13 (Flowchart XIII), a diagram illustrating an exemplary engineered portion for coupling the present invention with a traditional coal washing processing plant according to the discloses herein. Specifically, raw coal from coal mining, received by the coal receiving port of a coal washing plant, fed to a conveyor belt that transports the raw coal to an iron remover, then subject to a classification sieve. The plus mesh coal materials resulted from the classification sieve are loaded onto a hand selection conveyor belt that transports the same to a crusher. The minus mesh coal materials resulted from said classification sieve and the above crusher treated materials are mixed (hereafter referred to as “prepared raw coal”) and transported to coal washing, or to a storage holding place before coal washing. The prepared raw coal materials, subject to coal washing, produce clean coal and coal middlings as viable commercial products, but the byproduct, coal silt (slime) refuse, as waste, if discarded as pollutants, would impose negative environmental implications, both in the short and long terms, as shown in the background portion in the present disclosures. However, when coupled with the disclosed invention, as described and illustrated, for example, in FIGS. 1-12 (Flowcharts I-XII), additional commercially viable coal products such as clean coal and coal middlings are extracted from the coal refuse waste; water, as a valuable natural resource, used in the process are recovered, recycled, and reused in the closed system; and even the final coal waste resulted from the present invention, is not only in a much reduced amount, compared with conventional coal washing or preparation operations or coal mining processes, but also now useful as road-paving or brick-making materials, with minimal negative impact, if any, to the environment.
[0052] Referring to FIG. 14, Schematic Diagram of Present Invention Coupled with Coal Washing Plant, as illustrating an exemplary engineered portion for coupling the present invention with a traditional coal washing processing plant according to the discloses herein.
[0053] Referring to FIG. 15, Schematic Diagram of Present Invention, as illustrating an exemplary engineered portion for present invention as standing alone clean coal production plant according to the discloses herein.
[0054] The presently disclosed invention can recover coal components from coal refuse (waste), resulting in clean (fine) coal as products. About 80% of the coal content from the coal washing tailings generated by presently operating coal washing plants, which dispose or otherwise discard the coal tailings as coal refuse wastes with tremendous negative environmental implications. The clean (fine) coal products are valuable commodities, which are very much in demand for the industries such as electric power generation, iron and steel, cement production, heating, just to name a few. The clean (fine) coal production technologies as illustrated in the presently disclosed invention will add value to presently existing coal mining and coal washing operations, increase existing coal industry related job opportunities, improve economics, decrease pollutions to the environment from the existing coal industry globally.
[0055] Furthermore, the clean coal technologies disclosed in the present invention can be used to recover clean coal from discarded coal wastes left behind from the past, cumulated over the years or even decades, by coalmines and coal washing plants, which may no longer be in operations, thereby creating much needed new job opportunities, revitalizing local economics, reclaiming hazardous and polluted landmass, and turning the same into landscapes ready to be beautified, used, and enjoyed by many generations to come.
[0056] Samples (coal washing tailings delivered from different coal washing plants or different production batches of coal washing tailings delivered from a given coal washing plant) are obtained and tested to determine the initial baseline (or starting point) for their coal content (weight of coal content/total weight of coal washing tailings, expressed in %). Final clean coal (fine coal) products resulted from the presently disclosed invention are measured at their output points (plus screen and minus screen, respectively) and calculated against the initial baseline (starting point) coal content to determine the recovery rate (%). On average, the recovery rate of clean (fine) coal as products from the presently disclosed invention is about 80%, as shown in Table 1 with data points illustrating coal recovery rate of the disclosed invention in comparison with coal recovery rate of traditional coal washing plants
TABLE-US-00001 TABLE 1 Total Final recovered coal Recovery Rate Initial Coal recovered Coal recovered (recovered from plus (total recovered Sample Coal Content from plus screen from minus screen screen + recovered coal/initial Number (100-ash %) (0.1-2 mm) (0-0.1 mm) from minus screen) coal content %) 1 73.33 29.6 + 2.5 = 32.1 24.9 32.1 + 24.9 = 57 57/73.33 = 78 (Mar. 22, 2020) 4 67.97 26.7 + 20 = 46.7 17.7 46.7 + 17.7 = 64.4 64.4/67.97 = 95 (Apr. 2, 2020) 5 72.93 19.7 + 4 = 32.7 42.7 32.7 + 42.7 = 66.4 66.4/72.93 = 91 (Apr. 5, 2020) 6 68.4 20.6 + 15.8 = 36.4 18.1 36.4 + 18.1 = 54.5 54.5/68.4 = 80 (Apr. 6, 2020) 7 69 24.6 + 14.8 = 39.4 10.8 39.4 + 10.8 = 50.2 50.2/69 = 73 (Apr. 11, 2020) 8 63.1 5.8 + 0.8 = 6.6 32.2 6.6 + 32.2 = 38.8 38.8/63.1 = 62 (Apr. 13, 2020) Apr. 15, 2020 64.13 23.1 + 4.3 = 27.4 26.6 27.4 + 26.6 = 54 54/64.13 = 84 (2697) Apr. 15, 2020 57.2 24.1 + 19.1 = 43.2 7.9 43.2 + 7.9 = 51.1 51.1/57.2 = 89 (2698) Apr. 16, 2020 60 24.4 + 13.4 = 37.8 6.5 37.8 + 6.5 = 44.3 44.3/60 = 74 (2612) Apr. 16, 2020 56.11 23.1 + 4.5 = 27.6 15 27.6 + 15 = 42.6 42.6/56.11 = 76 (2699) Average: 80%
[0057] While the present invention has been described as having different embodiments, the invention may be further modified within the spirit and scope of the disclosures herein. This application is therefore intended to cover any variations, uses, or adaptations of the disclosed invention using its general principles. Furthermore, these disclosures are intended to cover such departures from, changes, or substitutions of the present disclosures made by those skilled in the art or as within known or customary practice in the art to which this invention pertains to and which fall within the limits of the appended claims.
