Application of current utilization technologies to coal solid wastes of the future

US utilities currently generate over 100 million tons of solid wastes per year. There is no single answer for the effective management of these wastes, but utilization to yield products that can be manufactured and marketed successfully is becoming increasingly attractive as an alternative to disposal. Most established uses are construction related and include road base materials, structural fill, cement admixtures, light-weight aggregate and land reclamation. Other relatively high technology applications such as mineral recovery and the separation of magnetite and censopheres are less well developed but offer significant opportunities. An important future consideration is the utilization of wastes resulting from new energy technologies and having different characteristics. Technologies included are fluidized bed boilers, flue gas dry scrubbers, and special multistage combustion burners. These developments will lead to replacement of pulverized coal fly ash with new ash forms which contain highly reactive materials such as alkaline oxides and sulfites. This paper briefly reviews current utilization technologies and examines their application to the solid wastes expected in the future.