Abstract: A method for processing aqueous radioactive wastes for noncontaminating and safe handling, transport and final storage wherein nitric acid and/or nitrate containing aqueous radioactive waste solutions are continuously denitrated with formic acid, spray-dried and calcinated in a spray dryer having a spray nozzle surrounded by a reaction chamber, the resulting calcinate is mixed with glass former substances, the mixture is melted and the melt is caused to solidify into a glass, glass ceramic or glass ceramic-like block and the waste gases produced during denitration-drying and calcination are conducted through a filter system in order to remove solid particles that have been carried along by the gas. The process steps of denitration, drying and calcination are effected simultaneously and are terminated with the aid of and the intimate energy exchange in the fine distribute droplets superheated steam in the vicinity of the spray nozzle.

Abstract: A process of preparing substantially solid wastes containing radioactive or toxic substances for safe, non-pollutive handling, transportation and permanent storage, wherein the wastes are mixed with polymerizable mixtures consisting essentially of monovinyl and polyvinyl compounds and polymerization catalysts, and are converted by polymerization into solid blocks.

Abstract: Method for preventing malfunctions in the solidification of radioactive wastes contained in an aqueous waste solution in a glass, glass ceramic or glass ceramic-like matrix wherein the wastes are spray-dried and calcinated. Diatomaceous earth or diatomaceous earth-like substances in solid form are added to the aqueous waste solution before the spray drying step in quantities of 45g/l to 70g/l and in grain sizes of which more than 85 percent by weight of the grain size distribution are grain sizes from 6 to 75.mu..

Abstract: A method of preparation for non-polluting storage of liquids containing phosphoric acid ester and hydrocarbons used in the reprocessing of spent nuclear fissile and/or fertile materials. The hydrocarbons are recycled for the production of fresh phosphoric ester-hydrocarbon solutions and the residue is brought into a form which can be fixed.

Abstract: A process of preparing substantially organic waste liquids containing radioactive or toxic substances for safe, non-pollutive handling, transportation and permanent storage, wherein the liquids are mixed with polymerizable mixtures consisting essentially of one or more monomeric monovinyl compounds and one or more polyvinyl compounds and polymerization catalysts, and the resulting mixtures are converted into solid blocks by polymerization at temperatures in the range of from 15.degree. to 150.degree. C.