Nuclear waste immobilization. Progress report

United States defense nuclear wastes are presently in tank storage, largely as sludges comprising Fe, Mn, Ni, U and Na oxides and hydroxides, together with 0.5 to 5 percent of fission products and actinides (exclusive of uranium). The relative proportions of Al, Fe, Mn, Ni, U and Na in the sludges from different tanks vary considerably, except that (Fe + Al + Mn) are by far the major components and Fe is more abundant than Mn. Typical compositions of some calcined sludges from Savannah River are given. This paper briefly describes how the SYNROC process, utilizing straightforward technology, can be readily adapted to the problem of defense waste immobilization, yielding a dense, inert, ceramic waste-form, SYNROC-D. Two classes of processes are discussed - one designed to immobilize sludges containing normal amounts of sodium and the other designed for otherwise similar sludges which are, however, strongly depleted in sodium as a result of more efficient washing procedures