Va. Tech turns coal sludge into a useful product

Researchers at Virginia Tech have discovered a way to transform coal sludge, the ultrafine coal particles that are the reside of the coal cleaning process, into a salable product. Funded by the National Energy Technology Laboratory, Professor of Mining and Mineral Engineering Roe-Hoan Yoon and his colleagues have developed a hyperbaric centrifuge that can efficiently dewater coal as fine as talcum powder, reports Newswise.

"The hyperbaric centrifuge is like the spin cycle on a washing machine, with the addition of compressed air," said Yoon. "Combining increased spinning and compressed air has a synergistic effect and cuts the moisture in half compared to conventional technology." The breakthrough is a welcomed by environmentalists and engineers, who once had to dispose of the product because of its unmarketable nature. Coal sludge is similar to ash, which is cleaned off in order to make coals burn longer and more efficiently.

"For me, that is a great accomplishment," said Yoon. "People living in coal-mining districts will see fewer and smaller slurry ponds. We have done something for the industry and for the public." Peter Bethell, a director of coal preparation at Arch Coal, says the product can be reused in the environment and improve economic returns. "It also goes to energy independence because we are using more of the available resource." Read more.