Abstract: A pyrochemical process is utilized to recover 99% of the remaining transuranium materials from plutonium-uranium extraction waste. One step of the overall pyrochemical process involves the electrochemical separation of the waste components. A solid anode and a solid cathode are used in this electrochemical separation step to electrorefine in single or multiple steps. The solid anode and solid cathode are selected from certain preferred anodic and cathodic materials. Where multiple electrorefining steps are used to obtain more complete electroseparation, this is achieved by employing in the multiple electrorefining steps both a solid anode, suitably graphite, and a molten metal anode containing a mixture of the actinide and rare earth elements. This results in greater separation than can be realized through electroseparation by use of either anode alone.

Abstract: A method of preparing active, sinterable, finely-divided plutonium oxide (PuO.sub.2) powder from plutonium metal is disclosed. The process yields plutonium fissile material which can be easily blended to form a uniformly homogeneous powder for the fabrication of high-quality light water reactor ceramic fuel pellets. Such homogeneous fuels are required to prevent hot spots from developing in a reactor using the fuel.

Abstract: An electrode is provided comprising a metal base and, on at least a portion of the metal base, a conductive material comprising a metallic mixture of antimony and lithium. This electrode may be utilized in an apparatus for electrochemical treatment of radioactive waste.

Abstract: To increase the operating temperature of a reactor, the melting point and mechanical properties of the fuel must be increased. For an actinide-rich fuel, yttrium, lanthanum and/or rare earth elements can be added, as stabilizers, to uranium and plutonium and/or a mixture of other actinides to raise the melting point of the fuel and improve its mechanical properties. Since only about 1% of the actinide fuel may be yttrium, lanthanum, or a rare earth element, the neutron penalty is low, the reactor core size can be reduced, the fuel can be burned efficiently, reprocessing requirements are reduced, and the nuclear waste disposal volumes reduced. A further advantage occurs when yttrium, lanthanum, and/or other rare earth elements are exposed to radiation in a reactor, they produce only short half life radioisotopes, which reduce nuclear waste disposal problems through much shorter assured-isolation requirements.

Abstract: A spray calcination process is provided for decomposing a metal nitrate solution to form fine grain multicomponent metal oxide powders of selected composition of particular utility as superconductor precursor powders. Such precursor powders are produced in bulk quantities as high purity, reproducible, intimately mixed powders for conversion to high temperature superconductors.A metal nitrate solution containing two or more metal constituents in a preselected ratio is sprayed as a finely atomized spray into a spray calcination zone where it is contacted with a hot gas stream for a residence time of less than 15 seconds at a high temperature between 200.degree. C. and 1100.degree. C. sufficient to vaporize the water of the nitrate solution and convert the metal nitrates to their corresponding oxides.

Abstract: Actinides metals are recovered from spent nuclear fuel oxides containing fission products by a pyrochemical process. The process comprises, in part, electrorefining the metal complex from an anode by electrolytically oxidizing actinides into a salt and then electrodepositing actinides onto a cathode to form an actinide metal deposit. The actinide metal deposit is then melted to separate the salts and the actinide metals. The separated salt is recycled into an electrorefiner and the actinide metals are recovered and then transferred to a fuel fabrication system.

Abstract: Ion exchange resin wastes are prepared for disposal by dewatering and/or dehydrating the resins, sealing the pores and recovering the ion exchange resins having radioactive waste products trapped within the sealed pores.

Abstract: A method of obtaining magnesium sulfate substantially free from radioactive uranium from a slag containing the same and having a radioactivity level of at least about 7000 pCi/gm. The slag is ground to a particle size of about 200 microns or less. The ground slag is then contacted with a concentrated sulfuric acid under certain prescribed conditions to produce a liquid product and a solid product. The particulate solid product and a minor amount of the liquid is then treated to produce a solid residue consisting essentially of magnesium sulfate substantially free of uranium and having a residual radioactivity level of less than 1000 pCi/gm. In accordance with the preferred embodiment of the invention, a catalyst and an oxidizing agent are used during the initial acid treatment and a final solid residue has a radioactivity level of less than about 50 pCi/gm.

Abstract: 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.

Abstract: A process is described for reducing the volume of a liquid waste containing an organic amine chelating agent in which a finely atomized spray of the liquid waste is contacted with a gas stream having a temperature in excess of the thermal decomposition temperature of the chelating agent. The proportions of the hot gas stream and liquid waste are controlled to rapidly evaporate water from the liquid waste and cool the gas to a temperature below the decomposition temperature of the chelating agent in a time of less than about 6 seconds to produce a dry, flowable powder product including the chelating agent.

Abstract: The volume of low-level radioactive wastes containing free water is reduced 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 the production of a dry, flowable radioactive solid product and a gaseous non-radioactive product which contains substantially no NO.sub.x or SO.sub.x and no volatile radionuclides, which are retained in the solid product.

Abstract: Bead ion exchange resin wastes are disposed of by a process which involves spray-drying a bead ion exchange resin waste in order to remove substantially all of the water present in such waste, including the water on the surface of the ion exchange resin beads and the water inside the ion exchange resin beads. The resulting dried ion exchange resin beads can then be solidified in a suitable solid matrix-forming material, such as a polymer, which solidifies to contain the dried ion exchange resin beads in a solid monolith suitable for disposal by burial or other conventional means.

Abstract: Polyhalogenated biphenyls such as PCB's, contained in transformer or capacitor oils, are removed from the transformer or capacitor oils by means of a combustible adsorbent which selectively adsorbs polyhalogenated biphenyls from transformer oils and the like. The adsorbent containing the adsorbed polyhalogenated biphenyls and the polyhalogenated biphenyls adsorbed thereon are destroyed by combustion in a molten salt.

Abstract: 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.

Abstract: Means for ensuring the accuracy and reliability of fluid flow measurements when the fluid contains substantial quantities of entrained particulates, the measurements being taken with a pitot tube and a pressure-sensing means wherein the pitot tube is disposed in a duct through which the fluid flows and has at least one velocity pressure-sensing orifice facing the upstream direction of flow. The means includes a remotely controllable rotation means for interposing a barrier between the orifice and the upstream direction of flow when velocity pressure measurements are not being taken. In accordance with one embodiment the rotation means comprises a remotely actuated cover and in another embodiment the rotation means comprises means for rotating the tube whereby the orifice faces in a downstream direction when velocity pressure measurements are not being taken. There also is provided means for purging the orifice.

Abstract: 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.

Abstract: A process for treating a metal recovery byproduct which contains solid ash constituents entrained in a melt comprising a major amount of a molten salt and a minor amount of molten metal in which the melt is filtered through a high-temperature filter apparatus containing a cylindrical rotating filter element to separately and continuously recover a filter cake containing the solid ash constituents and a molten filtrate containing the molten salt and molten metal. This molten filtrate may be directly recycled to the metal recovery process. The filter cake may be treated in an aqueous process to recover the salt therefrom for recycle to the metal recovery process. The invention is particularly applicable to the recovery of aluminum from its dross while removing ecologically damaging materials present in the ash.

Abstract: A process for the decomposition of polychlorinated biphenyls (PCB's) with negligible environmental pollution. The process comprises feeding the PCB and a source of oxygen to a molten salt comprising an alkali metal carbonate and preferably also an alkali metal sulfate to decompose the PCB by pyrolysis and oxidation. Some of the resulting decomposition products react with and are retained in the molten salt; the remaining gaseous products pass through the melt and are safely exhaustable to the atmosphere or, alternatively, the PCB is introduced into a first zone for partial pyrolysis and oxidation and then into a second reaction zone for further oxidation of any remaining combustible gases.

Abstract: An organic waste containing at least one element selected from the group consisting of strontium, cesium, iodine and ruthenium is treated to achieve a substantial reduction in the volume of the waste and provide for fixation of the selected element in an inert salt. The method of treatment comprises introducing the organic waste and a source of oxygen into a molten salt bath maintained at an elevated temperature to produce solid and gaseous reaction products. The gaseous reaction products comprise carbon dioxide and water vapor, and the solid reaction products comprise the inorganic ash constituents of the organic waste and the selected element which is retained in the molten salt. The molten salt bath comprises one or more alkali metal carbonates, and may optionally include from 1 to about 25 wt.% of an alkali metal sulfate.

Abstract: A method is shown for removing sulfur dioxide from a hot flue gas by absorption of the sulfur dioxide in an aqueous solution or slurry containing no more than 40 wt.% of an alkali metal carbonate or bicarbonate, preferably sodium carbonate and/or sodium bicarbonate using a spray-dryer scrubber to produce a dry mixture of sodium sulfite, sodium sulfate, and sodium carbonate and/or bicarbonate. Such a mixture is directly suitable as a feed to a regeneration stage.It is particularly preferred to regenerate the absorbent and recover commercial sulfur values in a closed-cycle process by next treating the solid absorption product in a molten salt reduction step with a reducing agent, preferably a carbonaceous material, to reduce the sodium sulfite and sulfate to sodium sulfide. Concurrently, a source of oxygen is fed to the reducer to generate sufficient heat therein for the reduction step by a combustion reaction.