[en] Wastes, in the form of liquids, solids and slurries, are converted to a mixture of a gas and an inorganic ash by introducing the waste as a finely atomized spray into a zone heated by means of a hot gas. Contact of the spray particles with the hot gas results in drying the waste and calcining and combusting the dried waste. The process is particularly useful with wastes containing hazardous materials such as radioactive substances

[en] A process is described for the thermal conversion of a radioactive waste material which comprises the sequential steps of: introducing the radioactive waste material in the form of a finely atomized spray into the top of a spray dryer zone heated, by means of a hot gas produced externally of the zone on combustion of a fuel and air and introduced into the top of the zone, to a temperature of about 500⁰ to 1000⁰C to convert the radioactive waste material, by contact with the hot gas, into a mixture of products including a non-radioactive gas comprising gaseous H/sub 2/O, CO/sub 2/ and nitrogen and a radioactive inorganic ash; removing the mixture of products from the bottom of the zone, and separating the radioactive inorganic ash from the mixture of products, the ratio of the volume of the radioactive waste material to the volume of the ash being in the range of about 7:1 to 70:1

[en] A method of treating an organic waste containing at least one of the volatile compound-forming elements strontium, cesium, iodine and ruthenium comprises introducing the organic waste and gaseous oxygen into a molten salt bath comprising an alkali metal carbonate or a mixture of an alkali metal carbonate and from 1 to 25 wt.% of alkali metal sulfate, the bath being maintained at a temperature of from 400⁰C to 1000⁰C and under a pressure of from 0.5 to 10 atmospheres to at least partially oxidise and combust the organic waste, the element or elements being retained in the molten salt bath. (author)

[en] The products of a molten salt combustion of hazardous wastes are converted into a cooled gas, which can be filtered to remove hazardous particulate material, and a dry flowable mixture of salts, which can be recycled for use in the molten salt combustion, by means of gas/liquid contact between the gaseous products of combustion of the hazardous waste and a solution produced by quenching the spent melt from such molten salt combustion. The process results in maximizing the proportion of useful materials recovered from the molten salt combustion and minimizing the volume of material which must be discarded. In a preferred embodiment a spray dryer treatment is used to achieve the desired gas/liquid contact

[en] A process is described for reducing the volume of a low-level radioactive liquid waste containing a compound of an element selected from the group consisting of I, Cs, Co and Mn. The process consists of: introducing the low-level radioactive liquid waste in the form of a finely atomized spray into a spray drying zone and contacting it with a hot gas stream within the zone, the gas stream having a temperature in the range of about 45⁰ to 300⁰ C. sufficient to vaporize the water contained in the low-level radioactive liquid waste but insufficient to produce any oxidation products of the low-level radioactive liquid waste or to volatilize any radionuclides therefrom; and removing from the zone a dry, flowable solid radioactive product containing the compound of the element and a gaseous product comprising water vapor, the gaseous product containing substantially no NO/sub x/, SO/sub x/, or oxidation products of the liquid radioactive waste and no volatile compounds of I or Cs, the ratio of the volume of the low-level radioactive liquid to the dry, flowable solid radioactive product being in the range of about 2:1 to 3.5:1

[en] A method has been developed for reducing the volume of organic wastes and recovering the actinide elements. The waste, together with gaseous oxygen (air) is introduced into a molten salt, preferably an alkali metal carbonate such as sodium carbonate. The bath is kept at 750⁰ - 1000⁰C and 0.5 - 10 atm to thermally decompose and partially oxidize the waste, while substantially reducing its volume. The gaseous effluent, mainly carbon dioxide and water vapour, is vented to the atmosphere through a series of filters to remove trace amounts of actinide elements or particulate alkali metal salts. The remaining combustion products are entrained in the molten salt. Part of the molten salt-combustion product mixture is withdrawn and mixed with an aqueous medium. Insoluble combustion products are then removed from the aqueous medium and are leached with a mixture of hydrofluoric and nitric acids to solubilize the actinide elements. The actinide elements are easily recovered from the acid solution using conventional techniques. (DN)

[en] This patent describes an improved metal alloy reactor fuel consisting essentially of uranium, plutonium, and at least one element from the group consisting of yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium

[en] A process for removing water from the pores of spent, contaminated radioactive ion exchange resins and encasing radionuclides entrapped within the pores of the resins, the process is described consisting essentially of the sequential steps of: (a) heating the spent ion exchange resins at a temperature of from about 100⁰C to about 150⁰C to remove water from within and fill the pores of the ion exchange resins by heating the ion exchange resins for from about 46 to about 610 hours at a temperature at which the pores of the resins are sealed while avoiding any fusing or melting of the ion exchange resins to encase radionuclides contained within the resins; and (b) cooling the resins to obtain dry, flowable ion exchange resins having radionuclides encased within sealed polymeric spheres

No abstract available

[en] To prevent the diversion of nuclear material from power production to weapon production either by a nation or by clandestine groups within a nation, the nuclear fuel cycle must be proliferation-resistant and safeguarded. Potentially proliferation-resistant and safeguarded fuel cycles based on low-decontamination pyroreprocessing have been developed for the light water reactor (LWR), fast breeder reactor (FBR), and FBR-LWR combination. The major penalty for recycling fission products to the LWR is that fuel enrichment must be somewhat greater to overcome parasitic fission product absorption of neutrons. In the FBR, the major penalty is a slight reduction in breeding ratio due to the displacement of fertile material by fission products. Preliminary cost analysis indicates that these fuel cycles are economically competitive with fuel cycles using conventional reprocessing or those using virgin uranium if spent fuel storage costs are considered