Published online by Cambridge University Press: 25 February 2011
Recent studies at Oak Ridge National Laboratory (ORNL) and elsewhere have identified various chemical processes for recovering useful materials, such as alumina and iron oxides, from coal combustion fly ash. Based on certain assumptions, each of these processes can yield useful products at economical prices. Most processes leave a residual solid waste with a volume only slightly less than that of the original waste. This residue may not present a serious hazard, but its volume alone makes disposal difficult for utilities with limited land available for disposal sites. Characteristics of some of the residues are being studied to determine possible beneficial uses or applications of these by-products.