Aaron Noble

Investigation of MCHM transport mechanisms and fate: implications for coal beneficiation.

4-Methyl cyclohexane methanol (MCHM) is a flotation reagent often used in fine coal beneficiation and notably involved in the January 9, 2014 Elk River chemical spill in Charleston, WV. This study investigates the mechanisms controlling the transport and fate of MCHM in coal beneficiation plants and surrounding environments. Processes such as volatilization, sorption, and leaching were evaluated through laboratory batch and column experiments. The results indicate volatilization and sorption are important mechanisms which influence the removal of MCHM from water, with sorption being the most significant removal mechanism over short time scales (<1 h). Additionally, leaching experiments show both coal and tailings have high affinity for MCHM, and this reagent does not desorb readily. Overall, the results from these experiments indicate that MCHM is either volatilized or sorbed during coal beneficiation, and it is not likely to transport out of coal beneficiation plant. Thus, use of MCHM in coal beneficiation plant is not likely to pose threat to either surface or groundwater under normal operating conditions.

Partitioning Behavior of 4-Methyl Cyclohexane Methanol in Two Appalachian Coal Preparation Plants

ABSTRACT To assess the environmental fate and partitioning of 4-methyl cyclohexane methanol (MCHM), plant-wide water-sampling surveys were conducted at two Appalachian coal preparation plants. Samples were recovered from various streams within the coal preparation plants as well as environmental discharges, including impoundment drains and groundwater-monitoring wells. The results indicate measurable MCHM concentrations are only found immediately around the flotation circuit (feed, concentrate, and tailings). Samples from downstream units, including thickeners, impoundments, and discharge points show no measurable concentration of MCHM implying that volatilization and adsorption are strongly influencing the measurable concentration.

Analysis of research scholarship for academic staff at US ABET accredited mining engineering schools by publications, citations and h-index

Publications, citations and h-index are three quantitative measures of scholarly productivity commonly used to evaluate university academic staff members. The quantity and quality of an individuals publication record is often an integral part of promotion and tenure decisions as well as post-tenure notoriety and awards. In this study, the Scopus database was queried to provide information on the scholarly productivity of 83 mining engineering academic staff members at accredited mining engineering schools in the United States. The data retrieved in this study include the number of publications, number of citations and h-index, for each individual academic staff member. Data for individual academic staff members was then classified by academic level/rank, institution and primary research sub-discipline to produce meaningful comparative results. The data show that the average number of publications per academic increases from 4 to 22 to 49 for assistant professors, associate professors and professors, respectively. Citations (9–83–290) and h-index (1–3–6) follow similar trends. Further analysis indicates that mineral processing and mine electrical systems are the most highly cited sub-disciplines. When aggregated by academic institution, the data show that the productivity of academic staff is linked to Carnegie Research classification. Finally, the data show a clear Pareto tendency with the highest 20% of academic staff members contributing 80% of the overall citations.

Coal Micro-Pricing: Optimizing the Coal Fuel Supply Chain for Indian Thermal Power Plants

ABSTRACT The energy sector in India is highly dependent on coal as a fuel. At present, most of the domestically produced thermal coal is burned raw or after minimal beneficiation. This practice often results in higher operating and maintenance costs, poorer utilization efficiencies, and increased greenhouse gas emissions. To improve the prevailing conditions, the Government of India is taking steps to increase clean coal production by promoting the installation of coal preparation plants across the country. The identification of optimal separation densities and blending protocols for these precombustion cleaning facilities greatly influences the economics of the fuel supply chain and India’s quest for additional low-cost energy. Traditionally, preparation plants have utilized float-sink (washability) data to determine suitable density separation set points for their processing circuits. Very often, these set points are based on the cumulative ash content required to meet contract specifications within India’s bulk commodity coal markets. Unfortunately, the current study indicates that the optimal separation densities are largely independent of coal washability characteristics. This article demonstrates the use of micro-price optimization to identify optimal density set points that maximize coal production for Indian coal feedstocks. This fundamental optimization technique assigns a unit price to each particle passing through the coal supply chain. This approach is in sharp contrast to the prevailing practice that assigns bulk prices to piles/lots of mixed coal and rock. Case studies for 12 different coal samples from India showed that (1) the historic constant cumulative ash method for determining set points is suboptimal, (2) the separation density of all plants/circuits should be held near-constant irrespective of feed washabilities, and (3) misplacement of high-ash rock and low-ash coal must be prevented to avoid large reductions in the inherent worth of India’s coal reserves.