Results of the development of a single-stage glass solidification method

In the U.S.S.R., the development of the single-stage continuous solidification process of high level radioactive wastes is proceeding. According to the method, the glass solidification process comprising dehydration and calcination is done in a single apparatus. The heating necessary in the process is made by applying A.C. to molten glass, whereby the process efficiency can be raised, and the melt in furnaces can be heated uniformly. In the research of the process, the model solutions of sodium nitrate and aluminum nitrate were used. To the solution, further the nitrates of iron, calcium, nickel, chromium, manganese, cerium and zirconium, and radioactive strontium-90, cesium-137 and ruthenium-106 were added. As the flux to make phosphate glass, orthophosphoric acid was used, and to make borosilicate glass, datolite and silicon dioxide were used. (J.P.N.)