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Showing 1 to 20 of 26 for “"coal preparation"”.
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Characterizing Trace Element Associations in the Pittsburgh No. 8, Illinois No. 6 and Coalburg Coal Seams
Coal preparation is widely regarded as a cost effective method for reducing the amounts of potentially hazardous air pollutant precursors (HAPPs) that occur as trace elements in the run-of-mine coals. Unfortunately, many existing coal preparation plants are inefficient in removing trace elements …
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Residual Diesel Range Organics and Selected Frothers in Process Waters from Fine Coal Flotation
… the potential fates of processing reagents in a coal preparation plant. The focus is specifically on petro-diesel (termed "diesel" in this paper), which is used as a collector in the flotation of fine coal. Diesel range organics (DRO) and polyaromatic hydrocarbons (PAHs) are measured in aqueous …
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Methods of Improving Oil Agglomeration
… that oil can spontaneously displace water from coal's surface if the coal particle has a water contact angle greater than 90°. However, the clean coal products obtained from laboratory-scale dewatering-by-displacement (DbD) test work assayed moistures substantially higher than expected. These …
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Potential Coal Slurry Toxicity to Laboratory and Field Test Organisms in the Clinch River Watershed and the Ecotoxicological Recovery of Two Remediated Acid Mine Drainage Streams in the Powell River Watershed, Virginia
… been documented by researchers. The presence of coal mining activity in the watersheds has been hypothesized to be linked to the decline of numerous species and the extirpation of others. The effects of various discharges from an active coal preparation plant facility located in Honaker, Virginia …
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A modern mining operation for the Virginia semianthracite coal field
… of a modern mining operation in the Valley Coal Fields of Virginia begins with a brief history of previous mining operations in the area. Following this is a study of the geological occurrence and a geographical description of the site selected. The deposit is studied from various angles - …
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Fine Coal Dewatering Using Hyperbaric Centrifugation
… separation processes employed by modern coal preparation plants require large amounts of process water that must be removed from the surfaces of particles using mechanical dewatering equipment. Unfortunately, the existing processes that are used to dewater fine particles are inefficient …
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Optimization of Integrated Coal Cleaning and Blending Systems
The fundamental requirement for a coal preparation plant is to transform low value run-of-mine (ROM) material into high value marketable products. The significant aspect relative to the plant is that any gain in efficiency flows almost entirely to the "bottom line" for the operation. The …
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Development of a Multi-Stream Monitoring and Control System for Dense Medium Cyclones
… cyclones (DMCs) have become the workhorse of the coal preparation industry due to their high efficiency, large capacity, small footprint and low maintenance requirements. Although the advantages of DMCs make them highly desirable, size-by-size partitioning data collected from industrial operations …
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An In-Plant Evaluation of Froth Washing on Conventional Flotation Cells for Coal
… cells have become increasingly popular in the coal industry due to their ability to improve flotation selectivity. The improvement can be largely attributed to the use of froth washing, which minimizes the nonselective entrainment of ultrafine minerals matter into the froth product. …
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DEVELOPMENT OF AN AUTOMATION AND CONTROL SYSTEM FOR A COAL SPIRAL
Coal spirals are widely used in coal preparation plants around the world to clean fine coal, typically in the 1 x 0.15 mm size range. Despite their popularity and the trend toward increased automation in modern coal preparation plants, adjustments to the critical process variable for coal spirals, …
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The effects of rapid mixing on the coagulation and sedimentation of ultra-fine coal and clay particles
As a consequence of new coal mining practices, coal preparation plants have been inundated with increased loads of coal and clay particles in their wastewaters. Traditionally, the industry has employed primary sedimentation as the fundamental treatment scheme for these sediment-laden blackwaters. …
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Improving Efficiencies in Water-Based Separators Using Mathematical Analysis Tools
… circuit analysis, identified an alternative coal spiral circuit configuration that offered improved performance while maintaining a reasonable circulating load. In light of this finding, a full-scale test circuit was installed and evaluated at an existing coal preparation facility. Data …
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On the energy and separation efficiency of dense medium cyclone coal beneficiation processes
… studies one of the most important processes in coal mining industry, dense medium cyclone (DMC) coal beneficiation process, in terms of energy and separation efficiency improvement. The pumping system used in the DMC process is studied to reduce its energy consumption and associated costs. The …
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Characterising the acid mine drainage potential of fine coal wastes
… mining history has led to a growing concern that coal-related AMD from these mines (both operational and defunct) will continue for centuries to come. Pyrite bearing fine waste, generated during coal preparation and beneficiation, is thought to carry a significant amount of AMD pollution risk. …
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Development of a video-based slurry sensor for on-line ash analysis
The implementation of process control in fine coal processing operations has traditionally been limited by the lack of adequate on-line ash sensors. Several nuclear based analyzers are available, yet none have seen widespread acceptance by the coal industry. This is due largely to their high cost, …
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Fine Coal Dewatering
Fine coal constitutes a relatively small portion of a product stream in a coal cleaning plant. However, its processing cost is approximately three times higher than the cost of processing coarse coal. Therefore, many coal companies chose to discard the fines to refuse ponds, causing a loss of …
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Scale-up of Using Novel Dewatering Aids
Coal preparation plants use large quantities of water for cleaning processes. Upon cleaning, the spent water must be removed such that the final product moisture level meets market constraints. However, removal of free water from the surface of fine particles is difficult and costly, and often the …
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Development and Testing of a Mobile Pilot Plant for the Advancement and Scale-up of the Hydrophobic-Hydrophilic Separation Process
… to this limitation, some mining sectors, such as coal, opt to discard the ultrafine particles to waste impoundments as the costs to recover and dewater these materials are prohibitive. The Hydrophilic Hydrophobic Process (HHS) is one alternative to flotation that uses a recyclable solvent, rather …
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Design and Testing of a Hyperbaric Horizontal Belt Filter for Fine Coal Dewatering
… recovery rate for all feed materials. Of the coal input, no less than 94% of it reported to the dry product. The pressure used to dewater the coal was the controlling factor for the air consumption of the unit. The data from these tests suggest that a full size production unit is feasible, …
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Petrography, chemical composition, and stratigraphic setting of the coals of North-Central Missouri
… a core drilling program to learn more about the coals in north-central Missouri. The stratigraphic setting and chemical and petrographic characteristics of 43 complete samples of coal recovered from 13 diamond drill holes in the exploration program in north-central Missouri are major …
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