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Showing 1 to 18 of 18 for “"Coal Refuse"”.
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Controlled Oxidation Studies of Coal/Refuse Fuel Blends
… combustion of blends of biomass materials and coals was conducted. Crushed limestone was added to the blends as an absorbent for sulfur oxides. The samples were combusted in quartz-fiber crucibles in a forced air furnace. Combustion at different times and temperatures were studied. The amount …
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Geoenvironmental aspects of coal refuse-fly ash blends
The separate land disposal of coal refuse and fly ash presents difficulties throughout the Appalachian region, both in terms of disposal costs per acre and in terms of its potential environmental impacts on soil, ground water, revegetation, and slope stability. The purpose of this study was to …
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Identification, Characterization, and Speciation of Rare Earth Elements in Coal Refuse
… placed upon the identification of REEs within coal refuse, but the phase designation and speciation is not fully understood. This investigation focuses on the characterization, speciation, and morphology of REEs within fine and coarse coal refuse. During this study, physical and chemical …
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Physical and chemical properties of coarse coal refuse from Southwest Virginia
Coarse coal refuse is difficult to reclaim due to high potential acidity and coarse fragment content, low water holding capacity, low fertility, and other problems. Little is known about coal refuse properties, particularly as they relate to revegetation potential. This study was undertaken to …
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Geotechnical characterization of coal refuse for use as a backfill material
… mine subsidence resulting from underground coal mining have caused surface damage to land and structures. A method of subsidence mitigation successfully used abroad, and to a much lesser extent in U.S. coal mines, is backfilling. In addition to the possible benefits of subsidence mitigation, …
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Concentration and Recovery of Rare Earth Elements from Eastern US Coal Refuse
… by the US Department of energy have shown that coal and coal byproducts contain elevated contents of Rare Earth Elements (REEs), making them a potential resource for these critical materials. The approach employed in this research focused on the concentration and extraction of REEs from fine …
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Evaluation of Leachate Chemistry from Coal Refuse Blended and Layered with Fly Ash
… ash has been studied as a liming agent within coal refuse fills to reclaim acid-forming refuse. Previous studies focused on bulk blending ash with acid-forming (pyritic) refuse. A better representation of field conditions is a "pancake layer" of ash above the refuse. A column study was …
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Influence of fly ash and other treatments on acid mine drainage from coal refuse
Most Appalachian coal refuse materials contain significant amounts of pyritic sulfur and are likely to produce acid mine drainage (AMD). A column technique was designed and implemented to evaluate the effects of various AMD mitigation treatments including fly ash, topsoil, lime, and rock-P. Two …
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The influence of fly ash additions on acid mine drainage production from coarse coal refuse
The exclusion of coal fly ash from regulation as a hazardous waste has led to increased interest in returning ash to the coalfields for disposal. Bulk-blending alkaline fly ash with acid forming coal refuse may present a disposal option that aids in the control of acid mine drainage. A preliminary …
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Performance and mechanism on a high durable silica alumina based cementitious material composed of coal refuse and coal combustion byproducts
<p>Coal refuse and combustion byproducts as industrial solid waste stockpiles have become great threats to the environment. Recycling is one practical solution to utilize this huge amount of solid waste through activation as substitute for ordinary Portland cement. The central goal of this …
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The Role of Earth Cover Depths and Upward Acid Diffusion on The Survival and Distribution of Vegetation on Coal Refuse Piles
Made available in DSpace on 2014-12-14T14:37:17Z (GMT). No. of bitstreams: 1 7606981.pdf: 5142330 bytes, checksum: 3b5e7e2fbeba92b48b23c1aba276b148 (MD5) Previous issue date: 1975
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LABORATORY AND FIELD INVESTIGATIONS OF COAL AND COAL PROCESSING WASTE - SIMULATION OF PRACTICES THAT MINIMIZE SULFATE AND CHLORIDE
The potential for mobilization of SO4 and Cl from coal stockpiles and coal processing waste and refuse (waste rock) disposal areas to the receiving streams and groundwater is an environmental concern and proper management practices are necessary to minimize the impact of these discharges. In an …
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An economic evaluation of backfilling in Virginia's coal mines
… to eliminate environmental problems caused by coal waste dumps, improve coal recovery, and improve mine ventilation. However, backfilling is an additional operation in the coal mining cycle that can reduce productivity and increase production costs. This thesis identifies the backfilling …
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Effect of Leaching Scale on Prediction of Total Dissolved Solids Release from Coal Mine Spoils and Refuse
Coal surface mining in the Appalachian USA coalfields can lead to significant environmental impacts including elevated total dissolved solids (TDS) levels in receiving streams. Column leaching procedures are recommended by many studies for TDS prediction, but many question their applicability to …
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Energy ans exergy analysis of biomass co-firing in pulverized coal power generation
Biomass co-firing with coal exhibits great potential for large scale utilization of biomass energy in the near future. In the present work, energy and exergy analyses are carried out for a co-firing based power generation system to investigate the impacts of biomass cofiring on system performance …
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The effect of carbon addition, pH and Fe concentration of microbial sulfate reduction and the subsequent precipitation of Fe and Mn from acid mine drainage in wetland mesocosms
… was constructed near Norton, VA by Westmoreland Coal Company to treat acid mine drainage (AMD) from an inactive coal refuse pile. The AMD had an average inflow pH of 7.0, and average inflow concentrations measuring 4 mg/L total Fe, 3 mg/L total Mn and 450 mg/L dissolved sulfate. An 18 month field …
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A study of selected control variables for a bottom-fed thickener
… bottom-fed thickeners used for the treatment of coal refuse slurries. The three variable parameters were "Feed Flow Rate," "Feed pH," and "Feed Solids Concentration." These three input parameters were studied under three polymeric conditions. The X-ray analysis of underflow refuse samples from …
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Flow Behavior of Granular Soil and Impounded Fly Ash Slurries
… of an embankment dam around mine tailings and coal ash slurry impoundments typically results in a fast-moving flow of toxic waste that can carry for several miles with disastrous consequence. The most recent catastrophic tailing-dam failure took place on 25 January 2019, at Brumadinho, Brazil, …