Department of Mining and Minerals Engineering

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https://hdl.handle.net/10919/24218

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Method for dewatering fine coal
(United States Patent and Trademark Office, 1995-10-17)
Fine coals are dewatered in an energy efficient process in which a non-polar liquid or a mixture of different hydrophobic liquids are used to displace the water from the coal surface. This process works with higher rank coals that are naturally hydrophobic so that the coal surface from which the water is displaced has a stronger affinity for the hydrophobic liquid than the water. Thermodynamically, this process is spontaneous and, hence, requires no energy. The only energy required for this process is to recover the spent hydrophobic liquid(s) for recycling purposes. The hydrophobic liquids are recovered in gaseous form either by lowering the pressure or by heating, and coverted back to liquid form for re-use. The most economical reagents that can be used for this purpose include propane, butane, pentane, and ethane. Carbon dioxide can also be used for the dewatering process described in the present invention. The process of dewatering by displacement is capable of achieving the same level of moisture reduction as thermal drying but at substantially lower energy costs.
Apparatus for improved ash and sulfur rejection
(United States Patent and Trademark Office, 1996-06-04)
An apparatus for separating impurities from coal, includes a device for removing a predetermined amount of ash-forming substances from the coal and a device for removing a predetermined amount of high specific gravity (e.g., pyrite) from the coal having been processed by the ash-forming substance removing device. The ash-forming substance removing device and the high specific gravity material removing device each possess characteristics that allow them to more efficiently reject different types of mineral impurities from coal.
News from Holden Hall, Fall 2009
(Virginia Tech, 2009)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
News from Holden Hall, Spring 2009
(Virginia Tech, 2009)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
News from Holden Hall, Spring 2010
(Virginia Tech, 2010)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
News from Holden Hall, Fall 2010
(Virginia Tech, 2010)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
News from Holden Hall, Spring 2011
(Virginia Tech, 2011)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
News from Holden Hall, Fall 2011
(Virginia Tech, 2011)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
News from Holden Hall, Fall 2012
(Virginia Tech, 2012)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
News from Holden Hall, Spring 2012
(Virginia Tech, 2012)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
Inhibition of Copper Pitting Corrosion in Aggressive Potable Waters
Sarver, Emily A.; Edwards, Marc A. (Hindawi, 2012-08-21)
Copper pitting corrosion can lead to premature plumbing failures, and can be caused by aggressive potable waters characterized by high pH, free chlorine residual and low alkalinity. In such waters and under continuous flow, certain inhibitors including phosphate, silica or natural organic matter may greatly reduce pitting occurrence. In the current work, 1 mg/L phosphate (as P) completely prevented initiation of pits, and 5 mg/L silica (as Si) significantly decelerated pitting. However, much lower doses of these inhibitors had little benefit and actually accelerated the rate of attack in some cases. Effects of organic matter were dependent on both the type (e.g., natural versus ozonated humic substances) and dosage. Dose-response effects of free chlorine and alkalinity were also investigated. Based on electrochemical data, pits initiated more rapidly with increased free chlorine, but even moderate levels of chlorine (~0.4 mg/L) eventually caused severe pitting. High alkalinity decreased pit propagation rates but did not prevent pit formation.
Reagents in coal processing: where do they go?
Morris, Josh; Sarver, Emily A.; Luttrell, Gerald H.; Novak, John T. (Canadian Institute Of Mining, Metallurgy And Petroleum, 2012-10)
A variety of reagents are utilized in coal preparation, but aside from performing their desired function relatively little is known about the behavior of these reagents within the processing circuits. Where exactly do reagents go once dosed? In this paper, we present preliminary results of partitioning studies on frother (i.e., MIBC) and collector (i.e., petro-diesel) chemicals commonly used in coal flotation, and examine implications for water management (e.g., in closed-loop systems). Additionally, we discuss the usefulness of such data in predicting environmental transport and fate of chemicals – which is currently a top priority for industry.
News from Holden Hall, Fall 2013
(Virginia Tech, 2013)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
News from Holden Hall, Spring 2013
(Virginia Tech, 2013)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
Application of Double-Difference Seismic Tomography to Carbon Sequestration Monitoring at the Aneth Oil Field, Utah
Slaker, Brent; Westman, Erik C.; Luxbacher, Kramer Davis; Ripepi, Nino (MDPI, 2013-10-23)
Double difference seismic tomography was performed using travel time data from a carbon sequestration site at the Aneth oil field in southeast Utah as part of a Department of Energy initiative on monitoring, verification, and accounting (MVA) of sequestered CO2. A total of 1211 seismic events were recorded from a borehole array consisting of 23 geophones. Artificial velocity models were created to determine the likelihood of detecting a CO2 plume with an unfavorable event and receiver arrangement. In tests involving artificially modeled ray paths through a velocity model, ideal event and receiver arrangements clearly show velocity reductions. When incorporating the unfavorable event and station locations from the Aneth Unit into synthetic models, the ability to detect velocity reductions is greatly diminished. Using the actual, recorded travel times, the Aneth Unit results show differences between a synthetic baseline model and the travel times obtained in the field, but the differences do not clearly indicate a region of injected CO2. MVA accuracy and precision may be improved through the use of a receiver array that provides more comprehensive ray path coverage, and a more detailed baseline velocity model.
News from Holden Hall, Spring 2014
(Virginia Tech, 2014)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
News from Holden Hall, Fall 2014
(Virginia Tech, 2014)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.
Considerations for TGA of Respirable Coal Mine Dust Samples
Scaggs, Meredith; Sarver, Emily A.; Keles, Cigdem (2015)
Respirable dust in coal mining environments has long been a concern for occupational health. Over the past several decades, much effort has been devoted to reducing dust exposures in these environments, and rates of coal workers’ pneumoconiosis (CWP) have dropped significantly. However, in some regions, including parts of Central Appalachia it appears that incidence of CWP has recently been on the rise. This trend is yet unexplained, but a possible factor might be changes in specific dust characteristics, such as particle composition, size or shape. Prior work in our research group has developed a standardized methodology for analyzing coal mine dust particles on polycarbonate filter media using scanning electron microscopy with energy dispersive x-ray (SEM-EDX). While the method allows individual particles to be characterized, it is very time-intensive because the instrument user must interrogate each particle manually; this limits the number of particles that can practically be characterized per sample. Moreover, results may be somewhat user-dependent since classification of particle composition involves some interpretation of EDX spectra. Respirable dust in underground coal mines has long been associated with occupational Jung diseases, particularly coal workers' pneumoconiosis (CWP) and silicosis. Regular dust sampling is required for assessing occupational exposures , and compliance with federal regulations is determined! on the basis of total respirable dust concentration and crystalline silica content by mass. In light of continued incidence of CWP amongst coal miners, additional information is needed to determine what role specific dust characteristics might play in health outcomes . While particle-level analysis is ideal, current time requirements and costs make this simply unfeasible for large numbers of samples. However, opportunities do exist for gleaning additional information from bulk analysis (i.e., beyond total mass and silica content) using relatively quick and inexpensive methods. Thermogravimetric analysis (TGA) may be a particularly attractive option. It involves precise sample weight measurement in a temperature controlled environment, such that weight changes over specific temperature ranges can be correlated to cheruical changes of particular sample constituents. In principle, TGA offers the ability to determine the coal and total mineral mass fractions in respirable dust samples. Such analysis could conceivably be combined with standard methods currently used to measure total mass and silica content. Under some circumstances , TGA might also be extended to provide information on specific dust constituents of interest (such as calcite). In this paper, we consider the benefits and challenges of TGA of respirable coal mine dust samples, and provide preliminary results and observations from ongoing research on this topic.
Preliminary Investigation of DPM Scavenging by Water Sprays
Rojas-Mendoza, L.; McCullough, E.; Sarver, Emily A.; Saylor, J. R. (2015)
News from Holden Hall, Spring 2015
(Virginia Tech, 2015)
"News from Holden Hall" is the Mining & Minerals Engineering department's semi-annual newsletter aimed at informing our friends and alumni on the latest events, highlighting exceptional faculty and student accomplishments, and describing the challenges we'll meet as we move forward into the next century.