Virginia Tech University in the US says that it has successfully developed a dewatering technology for ultrafine coal which can reduce moisture content to less than 20%.
Very fine coal with the consistency of talcum powder usually has to be discarded by even the most advanced coal cleaning plants because its moisture content in conventional dewatering systems make it impossible to sell on.
Dr Roe-Hoan Yoon, the Nicholas T Camicia professor of mining and mineral engineering at Virginia Tech and his colleagues have developed a hyperbaric centrifuge which could solve this problem. The technology uses both centrifugation and air pressure to achieve better results than those achieved using either of the two methods on their own.
“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.”