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Showing 1 to 20 of 50 for “"fine coal"”.
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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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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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Evaluation of Novel Fine Coal Dewatering Aids
The costs of cleaning fine coal are substantially higher than those of cleaning coarse coal. Therefore, many many coal companies in the U.S. choose to discard fine coal (150 micron x 0) by means of 6-inch diameter hydrocyclones. The cyclone overflows are stored in fine coal impoundments, which …
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An investigation of fine coal grinding kinetics
… in developing methods for preparing super—clean coal containing less than 2% ash and 0.5% sulfur. New techniques for recovering fine coal, such as micro—bubble flotation, can achieve the desired result provided mineral matter is sufficiently liberated. To achieve sufficient liberation, however, …
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Improved strategies for processing fine coal streams
In modern coal preparation plants, solid-solid and solid-liquid separation processes used to treat fine coal are least efficient and most costly operations. For example, field studies indicate that the froth flotation process, which is normally used to treat minus (-0.2 mm) fine coal, often …
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Cleaning and Dewatering Fine Coal using Hydrophobic Displacement
… both mineral matter and surface moisture from coal in a single process. Previous thermodynamic analysis suggests that coal moisture will be spontaneously displaced by any oil with a contact angle greater than ninety degrees in water. Based on these results, six methods of hydrophobic …
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Identification of Improved Stratigies for Processing Fine Coal
In modern coal preparation plants, solid-solid and solid-liquid separation processes used to treat fine coal are least efficient and most costly operations. For example, field studies indicate that the froth flotation process, which is normally used to treat minus (-0.2 mm) fine coal, often …
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Evaluation of an advanced fine coal cleaning circuit
A new fine-coal cleaning circuit, with potential near-term applications, has been evaluated for treating fine coal (i.e., 28 mesh x 0). This circuit combines a surface-based separator known as Microcel™ column flotation with an enhanced gravity separator known as the Multi-Gravity Separator (MGS). …
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Beneficiation of fine coal using the air-sparged hydrocyclone
… to be more efficient for the flotation of fine particles than conventional flotation equipment. The principal aims of this thesis were to investigate the use of an ASH in the flotation of South African coal ultrafines (-150 micron), and to determine the effect of various design and …
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Desulphurisation of fine coal waste tailings using algal lipids
… is an energy-driven economy which relies on coal to meet most of its energy demands. Coal mining has resulted in the generation of coal waste over 60 million tonnes, annually. Apart from the huge footprint of this waste, the sulphide minerals contained in the waste have resulted in the …
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Evaluation of column flotation circuits for fine coal cleaning
… to improve the column flotation of micronized coal. Laboratory flotation tests were performed with two different samples of Pittsburgh No. 8 seam coal. The first coal, Coal A, was ground to two different particle sizes and subjected to both column and conventional flotation. These tests were …
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Hydrodynamic studies and mathematical modeling of fine coal flotation
… model has been developed for the flotation of fine coal in a column. The model is capable of predicting the dynamic response of the flotation column to changes in a wide range of operational conditions. Model simulations have been found to be in reasonable agreement with experiments conducted …
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A preliminary investigation of microbubble flotation of fine coal
… recognized as the most viable means of cleaning fine coal, a loss in recovery rate and selectivity is encountered when attempting to apply the process to clean ultrafine coals. In this work, batch flotation tests were conducted on several Appalachian coals using microbubbles in a cylindro-conical …
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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 Novel Fine Coal Cleaning and Dewatering Technology
The cleaning and dewatering of ultrafine (minus 44 micron) coal slurries is one of the biggest challenges faced by coal industry. Existing commercial technologies cannot produce sellable products from these ultrafine streams; therefore, the industry is forced to discard this potential energy …
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Reverse flotation : a novel process for the beneficiation of fine coal
The beneficiation of ultrafine coal by froth flotation is a widely used process, and its importance for the treatment of -0.1 mm coal has been appreciated of late in South African coal washing plants. A number of problems adversely affect the efficiency of this process, such as poor liberation, …
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Development of a fine coal beneficiation circuit for the Twistdraai Colliery
The principal aim of this thesis was to develop a fine coal beneficiation circuit for the Twistdraai Colliery capable of achieving.a saleable 10.0% ash (28 MJ/kg CV) product. Gravity circuit testing involved a comparative study of a conventional double-stage Spiral circuit and a Stokes …
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A study of fine coal dewatering by high temperature and pressure filtration
The removal of water from fine coal (minus 3/8 inch, especially minus 48 mesh Tyler) has been a major problem of the coal industry. Thermal dryers have been used exclusively as a means of reducing the fine coal moisture. Because of its high capital, operating costs, and safety hazards, an alternate …
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Parameter Evaluation and Modeling of a Fine Coal Dewatering Screen-Bowl Centrifuge
A vast majority of coal and mineral cleaning and upgrading processes involve the addition of water. The water allows the movement of particles throughout the processing plant and the upgrading of the material. When the process is complete the finished product must be dewatered. This is due to …
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Design and Testing of a Hyperbaric Horizontal Belt Filter for Fine Coal Dewatering
… produce a lower moisture content and better fine particle recovery than current technology. To meet this goal, a hyperbaric horizontal belt filter was designed and constructed over the course of 18 months. Once built, the filter was then thoroughly tested to determine operational …
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