New coal dewatering technology turns sludge to powder

Because there has been no economically viable technology to remove water from ultrafine coal slurries, the ultrafine particles that are the residue of the coal cleaning process have been discarded into hundreds of impoundments. Now, Peter Bethell of Arch Coal Inc. reports that a dewatering technology developed at Virginia Tech has succeeded in reducing the moisture content of ultrafine coal to less than 20 percent, transforming it to a salable product.