Direct utilization-recovery of minerals from coal fly ash. Fossil Energy Program technical progress report, 1 April 1983-30 June 1983

A better understanding of the HiChlor process reaction mechanism was sought through a comprehensive study of the literature and a review of experimental data from work done at the Ames Laboratory. In the process, the oxides of Al, Fe, and Ti present in fly ash are extracted by high temperature chlorination in the presence of a solid or gaseous reductant. Information about the reactions involved is required for process development and for reactor design and operation. Three reaction mechanisms were proposed and evaluated. Other work dealt with feed preparation for two HiChlor process reactor configurations: packed and fluidized beds. Durable pellets of carbon fly ash mixtures are required in packed beds, and similar but smaller pellets are required in fluidized beds to prevent elutriation of the fine particles of fly ash out of the reactor. Work was expanded on the carbochlorination of coal fly ash in a fused salt (AlCl/sub 3/-NaCl) medium. Chlorination in a fused salt medium has the potential advantages for high reaction rates for a wide range of reaction conditions. The design and fabrication of an experimental, bench scale apparatus is nearly complete. Research on the sinter processes for extracting aluminates from coal fly ash focused onmore » a more complete evaluation of the effects of particle size of both the raw materials and the sintered clinker on the yield of alumina and on process economics. An investigation of aluminate recoveries as a function of temperature showed potential for ambient temperature extractions. 13 references, 9 figures, 3 tables.« less