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Summary of Consol Energy Summer Scholarship Program - Glenda France

During my employment at the UK Center for Applied Energy Research, I had the great opportunity to utilize my classroom knowledge in actual applications in the area of waste management. In this group, we focused on using various techniques of mineral processing for the beneficiation of fly ash, a byproduct that results from the burning of coal for fuel.

The sample I primarily worked with was from the ash pond of the Coleman Station power plant located in Hawesville, KY. We received the sample in slurry form in 55-gallon drums. In order to use the sample, we had to first classify it, which we did with a hydraulic classification technique. The fines, which overflowed the top of the column, were saved to be processed in the pilot plant. The coarse material, which settled in the bottom, was run over a bank of spirals to separate the carbon from the fly ash by density. This carbon was analyzed and found to have a grade of nearly 80% carbon.

The fines were processed using froth flotation. A collector was added to the slurry which was selective to carbon in order to make it more hydrophobic (an aversion to water) along with a frother to lower the surface tension of the water and make lots of small air bubbles to carry the carbon to the top, thereby making a stable froth that could be scraped off and collected. The resulting froth (or concentrate) was then cleaned by column flotation to raise the grade of the carbon. The remaining low-carbon ash in the float cells (or tails) is commonly used as pozzolan, but was further classified by methods of dispersion to obtain filler ash, an ingredient in the manufacture of plastics.

Overall, it was a fascinating learning experience. I was even able to share my newfound skills with high school students from Eastern Kentucky (my home) at the Hal Rogers Institute for Rural Development, a program designed to try and keep our educated youth in Kentucky. My classes of Minerals Processing, Advanced Minerals, and Coal Preparation became much clearer after having spent this summer applying the principles I knew in theory only. Thank you for the opportunity of a lifetime to be able to put the knowledge of the classroom to work.