Abstract: A wastewater treatment system and process for removal of radioactive particulates includes continuous monitoring of charged particles and the addition of chemicals to coagulate and cause removal of the particulates from the wastewater.

Abstract: A process is disclosed for the treatment of a solvent which has been used in nuclear fuel reprocessing or uranium ore purification, the solvent comprising an organophosphate ester and a hydrocarbon diluent. The process includes distilling the solvent under reduced pressure to remove substantially all the diluent and a major proportion of the organic ester, converting organophosphate to inorganic phosphate and encapsulating the residual material.

Abstract: A system and method for filling, dewatering and sealing high integrity containers for storing high level radioactive debris has a support structure for receiving a container and a movable hood supported over the support structure. The movable hood is movable between a filling/dewatering position, an intermediate position, and a sealing position. Fill and dewatering lines extend through the hood and have flexible lower portions with connectors for interfacing with the container to be filled. The flexible lower portions are movable into and out of engagement with respective connectors on the container when the hood is in the filling/dewatering position. A plurality of valves are provided to isolate the fill and dewatering lines to minimize release of radioactive debris during connector mating and demating operations. A straw extends through the hood for removing water from an upper volume of the container when the hood is in the intermediate position.

Abstract: Processes of reductive decontamination using an agent containing at least two kinds of components, and then decomposing the agent using an apparatus for decomposing at least two kinds of chemical substances in the agent, are employed in chemical decontamination. A catalyst decomposition column in an upstream side of an ion exchange resin column and a hydrogen peroxide injection apparatus in a further upstream side, reduce the amount of waste products caused by a chemical decontaminating agent where a mixed decontaminating agent for a composition trapped in a cation resin column and for a composition trapped in an anion exchange resin are used for the chemical decontaminating agent, selectively decompose the composition trapped in the cation resin column in an inlet side of a cleaning apparatus when radioactive nuclides in the decontaminating agent are cleansed using the cation resin column during decontamination, and decompose both compositions after completion of the decontamination.

Abstract: A process for chemical fixation of radionuclides and radioactive compounds present in soils, solid materials, sludges and liquids. Radionuclides and other radioactive compounds are converted to low-temperature Apatite-Group structural isomorphs (general composition: (AB)5(XO4)3Z), usually phosphatic, that are insoluble, non-leachable, non-zeolitic, and pH stable by contacting with a sulfate, hydroxide, chloride, fluoride and/or silicate source and with a phosphate anion in either a one or two step process. The Apatitic-structure end product is chemically altered from the initial material and reduced in volume and mass. The end product can be void of free liquids and exhibits sufficiently high levels of thermal stability to be effective in the presence of heat generating nuclear reactions. The process occurs at ambient temperature and pressure.

Abstract: Organic materials are mixed with metal oxide, such as hydrated metal oxides, prior to or during heat treatments in aerated or oxygenated environments to stabilize thermal decomposition or incineration of the organic materials and to suppress the emission of volatile, hazardous organic compounds. The organic materials may be ion exchange resins and polymeric sorbents, for example, and include contaminated materials such as hazardous wastes. The hydrated metal oxides may be hydrated ferric oxide, hydrated aluminum oxide or hydrated titania oxide, for examples. Ferrihydrite is preferred. The heat treatment may be a preparation for a waste disposal process, such as immobilization in ferric oxide, cement, concrete, a polymer, bitumen or glass, for example. Immobilization processes in ferric oxide are also discussed, including the use of additives such as magnesium oxide, ammonium dihydrogen phosphate and phosphoric acid, enabling consolidation at room temperature and pressures less than 15,000 psi.

Abstract: A method is disclosed for recovering and separating precious and non-precious metals from waste streams, which removes, separates, and recovers such metals in a cost effective manner with more than 95% removal form waste streams and with minimal amounts of unprocessed solids and sludge remaining in the environment. Metals such as chromium, manganese, cobalt, nickel, copper, zinc, silver, gold, platinum, vanadium, sodium, potassium, beryllium, magnesium, calcium, barium, lead, aluminum, tin; and the lie are removed and recovered from the waste streams with at least 95% removal and other metals and compounds, such as antimony, sulfur, and selenium are removed and recovered from waste streams with at least 50% removal. The method employs a unique complexing agent comprising a carbamate compound and an alkali metal hydroxide which facilitates the formation of the metals into ionic metal particles enabling them to be readily separated, removed and recovered.

Abstract: A method for the treatment of radioactive evaporator concentrates from the evaporation system of nuclear plants comprises the steps of (a) freeing the evaporator concentrates from undissolved components, (b) crystallizing the sodium sulfate contained in the evaporator concentrates as Glauber's salt (Na2SO4.10 H2O) on an immersion cooler, (c) recrystallizing the Glauber's salt deposited on the immersion cooler, (d) optionally, repeating the recrystallization step (c) once or several times, (e) separating essentially inactive sodium sulfate from the process, and (f) recycling the depleted evaporator concentrates of step (a) to the evaporation system.

Abstract: The present invention uses fish bones and fish hard parts to remediate, clean-up, stabilize, immobilize, or otherwise treat metal-contaminated water, soil or waste of any sort. The fish bones and fish hard parts can be mixed in with soils and wastes, or emplaced as a permeable reactive barrier in a trench or excavation, or emplaced as a liner or barrier surrounding a waste form, disposal site, or contaminated site. All that is needed is intimate contact between the fish bones and fish hard parts and the contaminated waste form, soil particles, or water. In a system of, for example, soil, waste, groundwater, surface water, waste streams, or the digestive tracts of animals, the presence of fish bones and fish hard parts reduces the amount of metal that can mobilize and migrate out of the system. Fish bones and fish hard parts remove metals from waters passing through the system or originating within the system.

Abstract: The AVS invention provides for an apparatus and process for its practice involving the vitrification of waste materials, such as nuclear waste, inside a disposable canister. The preferred embodiment of the process includes a canister having outer and inner containers with thermal insulation therebetween. Solid frit sections are placed inside the inner container to create one or more regions for receiving waste. The waste is then loaded into the regions. The inner canister is heated to melt the frit and waste and mix them once molten. The melted mixture is then cooled to form a vitrified product in the module. In an alternative process, chunks of frit are mixed with waste and loaded into the empty canister. The mixture is then melted and cooled inside the disposal canister.

Abstract: A filtration system for concentrating radioactive debris particulate provides efficient filtration, concentration and transport to collection canisters of radioactive particles from a refueling cavity, spent fuel pool, or other water volume where small particles must be removed from the water. The system includes a flushing pump module that draws contaminated water from a cut zone enclosure. The flushing pump module has a separator that removes large size particulate from the contaminated water. A solid media filter module receives the contaminated water from the flushing pump module and removes medium size particulate from the contaminated water. The solid media filter module has a structure for ejecting the medium size particulate and passing the ejected particulate to a concentrate handling module having a purge tank and a slurry transfer pump. A disposal canister station receives the medium size particulate from the slurry transfer pump and fills disposal canisters for transport and storage.

Abstract: Liquid metal coolants, such as alkali metal used in nuclear reactor systems can be safely deactivated to form a disposable solid waste material. The alkali metal is dissolved in an ammoniacal liquid, such as anhydrous liquid ammonia to form a reaction mixture comprising alkali metal cations and solvated electrons. A precipitating agent that ionizes in the liquid ammonia is introduced into the reaction mixture to combine with the alkali metal cations and/or solvated electrons to form a precipitating alkali metal salt. Additionally, solidified alkali metal remaining within the coolant system after initial drainage of liquid alkali metal can be dissolved by circulating an ammoniacal liquid within the coolant system. Removal of the liquid ammonia having the alkali metal dissolved therein is combined with a ionizable precipitating agent to form a alkali metal salt.

Abstract: The present invention is directed to a material-radioactive isotope combination, comprising a container made from a material and a radioactive isotope solution. The container is useful for the storage, shipment, or storage and shipment of the radioactive isotope. Preferably the material is characterized by having a nearly full compliment of double carbon bonds so that little, or no hydrogen is produced by the material in the presence of the radioactive isotope. Furthermore, the preferred material exhibits greater mechanical strength than that of glass, resistance to a temperature range of from about -40.degree. to about 160.degree. C., chemical inertness; and radiation resistance. An example of such materials includes PSF (polysulfone) and PETG (polyethylene terephalate G copolymer) and the radioactive isotope, of the material-radioactive isotope combination are selected from, the group consisting of Mo-99, I-131, I-125. W-188 and Cr-51.

Abstract: Processes for immobilizing solid contaminated materials, such as radioactive species, hazardous species, or combinations of both radioactive and hazardous species, comprise mixing the contaminated materials with hydrated ferric oxides, and then pressing the mixture at a temperature of at least about 150.degree. C. and gradually removing a large part of the water while under pressure to produce a solid composition. The water content of the mixture is adjusted if necessary. Contaminated materials dissolved or suspended in an aqueous solution can be immobilized by precipitating hydrated ferric oxide in the solution, and adjusting the water content and pressing, as above. In another process in accordance with the present invention, hydrated ferric oxides are deposited on metal surfaces. The deposited ferric oxide is pressed to produce a solid coating adhered to the surface, to retard corrosion. A ceramic body of ferric oxide composition may also be made in accordance with the present invention.

Abstract: Procedure for the treatment of radioactive hazardous waste, in which procedure oxygen is treated with radio-frequency electromagnetic radiation in a manner known in itself so that the oxygen forms a cold plasma, and the waste and the oxygen are fed together.

Abstract: In a method and an apparatus for dewatering and containing radioactive, aqueous waste (44), the latter is introduced into a filtration container (12) and is ultimately disposed of in a disposable container structure (12, 48, 50), which comprises the filtration container (12) holding the dewatered waste (44), as well as an outer container (50) enclosing the filtration container (12). The filtration container is an inner sack (12) having a bottom (13) which is provided with a straining cloth and through which essentially all the dewatering is carried out. After the dewatering operation has been completed, the inner sack (12) is sealed and placed in the outer container (50) in order to be ultimately disposed of. For purposes of cleaning, the filtration water (17) may be recirculated through the waste during the dewatering operation.

Abstract: A unique method for solidification of solutions containing boric acid and/or borates is disclosed in this invention. The boron species in the solutions are polymerized to form polyborates, and the solutions are then solidified by mixing with solidification agents which are prepared completely from inorganic materials. Therefore, the solid form produced by this method has no aging problem. The boron species in the solution are not merely wastes to be encapsulated or embedded, they take part in the solidification reaction and share a major portion of total reactants. Thus, the total volume of solid forms produced in this invention is less than 1/10 of that produced in conventional cementation.

Abstract: A process for chemical fixation of radionuclides and radioactive compounds present in soils, solid materials,sludges and liquids. Radionuclides and other radioactive compounds are converted to low-temperature Apatite-Group structural isomorphs (general composition: (AB).sub.5 (XO.sub.4).sub.3 Z), usually phosphatic, that are insoluble, non-leachable, non-zeolitic, and pH stable by contacting with a sulfate, hydroxide, chloride, fluoride and/or silicate source and with a phosphate anion in either a one or two step process. The Apatitic-structure end product is chemically altered from the initial material and reduced in volume and mass. The end product can be void of free liquids and exhibits sufficiently high levels of thermal stability to be effective in the presence of heat generating nuclear reactions. The process occurs at ambient temperature and pressure.

Abstract: Disclosed is a method of disposal of metallic aluminum-containing solid waste comprising the steps of reacting radioactive solid waste containing metallic aluminum with an alkali solution to generate a hydrogen gas and then mixing the resulting reaction liquid with a solidifying material containing a latent hydraulic material as a main component to solidify the liquid. According to the method of the invention, solidification of aluminum-containing radioactive solid waste in a highly filled state (high concentration) is feasible and a solid having excellent mechanical strength and properties of preventing oozing of radioactive nuclide can be obtained.

Abstract: A process for treating oils and solvents contaminated by radioactive substances includes a step of subjecting the oils and solvents to the action of pre-selected micro-organisms in the presence of air and a very large volume of water, relative to the volume of oils and solvents to be treated. The micro-organisms destroy organic molecules, and in particular transform them into CO.sub.2 and H.sub.2 O. Further steps of the process include preparing a predetermined volume of water having predetermined characteristics of dissolved oxygen concentration, pH and redox potential and adding a predetermined charge of oils and solvents contaminated by radioactive substances to this volume of water, the charge corresponding to a volume of oils and solvents which is a predetermined fraction of the predetermined volume of water. The charge is subjected to the action of micro-organisms at a predetermined temperature and for a predetermined time period.

Abstract: A method for reducing radioactive waste, particularly oils and solvents in nuclear power stations and military research centers, and a device therefor. The method comprises feeding the waste into a tank (1) in which it is continuously stirred, preheating the waste, performing a chemical precipitation treatment, feeding the mixture into a centrifuge (2), performing an electrostatic or conventional filtration step, and testing the level of radioactivity. The treatment is continuously repeated until the desired level of decontamination is reached.

Abstract: Methods are provided to at least slow the dissolution of silica in an aqueous environment. In the subject methods, the silica surface is contacted with a multivalent metal cation capable of complexing with oxygen atoms present on the silica surface, where contacting is preferably accomplished by introducing a source of the multivalent metal cation into the aqueous environment. The subject methods find particular use in the inhibition of the dissolution of silica comprising neutron poisoning materials employed in the storage of spent nuclear fuel.

Abstract: In order to treat an aqueous acid effluent resulting from the decontamination of a component of a nuclear power station, the effluent containing an organic load comprising an organic reducing agent and nitrate ions and at least one oxidizing compound is introduced into the effluent. The effluent is then subjected to ultraviolet radiation and the totality of the organic load is thus converted into water and carbon dioxide, as well as possibly into at least one oxide of a chemical element present in the organic load, while neutralizing the effluent.

Abstract: Although a chelating agent solution having radioactive contaminants is solidified by mixing with cement and then stored, a vast storage place is required for storing an enormous amount of chelating agent solution. When such a chelating agent solution is treated with an ion-exchange resin, a large amount of ion-exchange resin is required, and a large amount of ion-exchange resin having radioactive contaminants is produced. The present invention thus provides a method of treating a chelating agent solution having radioactive contaminants, which can significantly decrease the amount of the chelating agent solution having radioactive contaminants, and which, when an ion-exchange resin is used, can significantly decrease the load on the ion-exchange resin without producing a large amount of ion-exchange resin having radioactive contaminants.

Abstract: This invention relates to the processing of liquid radioactive waste containing radioactively labeled biological molecules. More specifically, this invention relates to the use of solid phase binders to remove radioactively labeledbiological molecules from liquid radioactive waste solutions.

Abstract: An apparatus for cleaning a separator is disclosed. Generally, the apparatus includes a vessel connected to a well that produces an effluent. The vessel is used for separating the effluent. Also included is a discharge member which is attached within the vessel for discharging a liquid onto solids located at the bottom of the vessel, and a drain adapted for draining the solids from the bottom of the vessel. The apparatus may further include a chemical injection device, operatively associated with the discharge member, for injecting a radioactive dissolution chemical. A process for cleaning the vessel and treating the entrained solids of the effluent with the radioactive dissolution chemical is also described.

Abstract: Processes for in-situ decontamination and recovery of metal from radioactive-contaminated metal which is contained in process equipment, including ancillary systems of process equipment, comprise two basic steps. In the first step, an acid decontamination solution is circulated through the equipment and in contact with the radioactive-contaminated metal for removing the radioactive contaminants and a first surface portion of the metal from the metal-containing equipment. In the second step, an acid digestion solution is circulated through the equipment for removing at least a second portion of the metal which is substantially free of radioactive contaminants. The present methods are particularly suitable for in-situ decontamination and recovery of nickel from radioactive-contaminated nickel diffusion barriers in the cascade converters of uranium gas diffusion plants.

Abstract: A process for treating a radioactive waste, includes drying a radioactive waste containing a radioactive substance(s) and a sodium compound(s), to convert it into a dried material, heating the dried material to convert it into a molten salt, and subjecting the molten salt to electrolysis using the salt as an anolyte and .beta.-alumina as a sodium ion-permeable membrane. This process can recover metallic sodium or sodium hydroxide, each of extremely low radioactivity from a radioactive waste containing a radioactive substance(s) and a sodium compound(s), at a high purity at a high current efficiency.

Abstract: Mixed radioactive wastes, such as those that include a radioactive component and a dissolved salt component, are treated by directing the waste through at least one ion-exchange medium that binds at least a portion of the radioactive component. A liquid discharge stream from which the radioactive component has been separated, and which includes the dissolved salt component, is directed into a molten bath that causes at least a portion of at least one dissolved salt component of the liquid discharge stream to be reductively vaporized and thereby form at least one vaporized product. A gaseous discharge stream is generated by the molten bath that includes at least one vaporized product. In one specific embodiment, the mixed radioactive waste includes radioactive cesium as the radioactive component and sodium nitrate as the dissolved salt component.

Abstract: The present invention relates to a method for treating radioactive laundry waste water generated from a nuclear power plant, nuclear fuel reprocessing plant, or radioactive nuclides handling facilities, and provides a method for treating the waste water safely and for reducing the volume of generated radioactive waste to a minimum.Radioactive laundry waste water containing a detergent of which major contents are a nonionic surface active agent and inorganic builders is concentrated by an evaporating concentrator, the concentrated waste water is dried and pulverized to dry powder by a rotary centrifugal thin film dryer, and the dry powder is incinerated. By using the above detergent, foaming at the concentration can be reduced, and the concentrated waste water can be easily dried and pulverized. Further, the dried powder can be incinerated stably and safely without influencing undesirable effect on the body of the incinerator.

Abstract: An adsorbent for radioactive nuclides incorporating fibrous activated carbon. The adsorbent includes fibrous activated carbon having good adsorption performance, inorganic fiber and inorganic binder. Therefore, the adsorbent exhibits good shape stability when it is formed into a molded piece, has good combustion performance, and is not liable to scattering of radioactive nuclides adsorbed thereon when it is incinerated.

Abstract: Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulphur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described.

Abstract: The present invention describes a process to reduce the volume and/or weight of magnesium slag when the magnesium slag contains radioactive thorium. The process contacts the magnesium slag as an aqueous slurry with an acid in a pH range from about 4.0 to about 8.0, preferably from about 5.0 to about 5.5, followed by separating insoluble solids from the aqueous solution. Optionally, the acid digested solids are heated, either before or after the acid digestion, at a temperature from about 350.degree. to about 500.degree. C. The solid waste can then be further compacted, if desired, prior to disposal.

Abstract: Preparation and use of polymeric materials containing hydrophobic anions and plasticizers for extraction of cesium and strontium. The use of polymeric materials containing plasticizers which are solvents for hydrophobic anions such as derivatives of cobalt dicarbollide or tetraphenylborate which are capable of extracting cesium and strontium ions from aqueous solutions in contact with the polymeric materials, is described. The polymeric material may also include a synergistic agent for a given ion like polyethylene glycol or a crown ether, for removal of radioactive isotopes of cesium and strontium from solutions of diverse composition and, in particular, for solutions containing large excess of sodium nitrate.

Abstract: A method of reducing the concentration of neptunium and plutonium from alkaline radwastes containing plutonium and neptunium values along with other transuranic values produced during the course of plutonium production. The OH.sup.- concentration of the alkaline radwaste is adjusted to between about 0.1M and about 4M. [UO.sub.2 (O.sub.2).sub.3 ].sup.4- ion is added to the radwastes in the presence of catalytic amounts of Cu.sup.+2, Co.sup.+2 or Fe.sup.+2 with heating to a temperature in excess of about 60.degree. C. or 85.degree. C., depending on the catalyst, to coprecipitate plutonium and neptunium from the radwaste. Thereafter, the coprecipitate is separated from the alkaline radwaste.

Abstract: This invention provides a process wherein hazardous or radioactive wastes in the form of liquids, slurries, or finely divided solids are mixed with finely divided glassformers (silica, alumina, soda, etc.) and injected directly into the plume of a non-transferred arc plasma torch. The extremely high temperatures and heat transfer rates makes it possible to convert the waste-glassformer mixture into a fully vitrified molten glass product in a matter of milliseconds. The molten product may then be collected in a crucible for casting into final wasteform geometry, quenching in water, or further holding time to improve homogeneity and eliminate bubbles.

Abstract: According to the invention, a consumable anode constituted by a metal alloy incorporates between 20 and 70 wt. % iron, between 20 and 40 wt. % cobalt and between 5 and 30 wt. % aluminium. To these basic constituents can optionally be added elements such as nickel and/or titanium and/or copper and/or niobium. The decontamination process involves an electrodissolution of said anode.

Abstract: A process for preparing radioactive and other hazardous liquid wastes for treatment by the method of vitrification or melting is provided for.

Abstract: A method is presented for releasing petroleum and hydrocarbon products sorbed onto or entrained by natural fibers in an aqueous medium through the use of enzymes to degrade the natural fiber sorbents utilized for oil spill cleanup, the method provides an opportunity for achieving responsible separation of oil from oil spill sorbent materials. Natural fibers which have been utilized to adsorb petroleum and hydrocarbon products are separated from these petroleum and hydrocarbon products by reducing the natural fiber links to the point that the adsorbed or entrained oil no longer has sufficient binding surface or fiber link to remain held by the fibers, thus float to the surface of the aqueous medium. Aqueous medium enzyme compositions are provided which are suitable for degrading natural fibers inclusive of cellulose-based and protein-based fibers resulting in release of adsorbed, absorbed and/or entrained radioactive contaminants.

Abstract: A method for separating boric acid from a liquid, especially liquid waste obtained from a nuclear power plant. In the method, the waste solution containing the boric acid is contacted with steam in a reactor so that the boric acid evaporates from the liquid and passes into the steam vapor phase. Consequently, the radioactive wastes which are not evaporated with the steam remain in the waste water while the boric acid is removed from the waste water when it passes into the vapor or steam phase. The boric acid can then be separated and recovered from the steam by means of a distillation and fractionating column or a wash column. By removing the boric acid from the liquid waste, it is possible to obtain concentrated radioactive waste having a reduced volume due to the absence of boric acid in the waste.

Abstract: A method is disclosed for treating liquid radioactive waste to provide reusable water, while reducing the overall volume and water content of the removed solid contaminants. The process is carried out in two separate stages, generally in at least two separate locations. In the first stage, the waste is pretreated at a first site, preferably where the waste was generated, to provide clean water, and a concentrated fraction containing removed suspended and dissolved solids, as well as some remaining water. The pretreatment typically involves passing the liquid waste through one or more microfilters, ultrafilter or nanofilters in combination with a reverse osmosis membrane. In the second stage of the process, the concentrated waste fraction, containing the removed solids, is transported to a second site, where it is thermally treated to remove the remaining water and reduce the volume of the remaining solids.

Abstract: A borated aqueous solution from a nuclear reactor coolant system dilute chemical-decontamination process or from an equipment washing process which has been contaminated with radioactive metals or heavy metals including cobalt, nickel, chromium, iron, manganese, lead or mercury and with a chelating agent, detergent or soap is treated with an oxidizing agent to oxidize the chelating agent, detergent or soap and to precipitate the contaminant metals. The contaminant metals are then separated from the solution by centrifugal filtration, micromembrane belt filtration or magnetic separation. Advantageously, a very small volume of precipitate may then be buried and the decontaminated solution may be recycled or further treated and released for other uses.

Abstract: A process for removing liquid from depleted ion exchange bead resin includes the steps of: transferring a slurry containing at least 10 volume % of contaminated ion exchange resin beads from storage (10) having a particle size range from 300 micrometers to 1000 micrometers to a blending tank (14) to provide a homogeneous slurry which is fed to a grinder (16) usually by means of pumps (13 and 17), where the beads are fractured, and reduced in size, where no more than 33% of the fractured beads have a relatively similar diameter, allowing subsequent random packing compression; and then passing the processed slurry to a dewatering system (18) where it is separated into liquid (20) and highly compressible waste (22).

Abstract: This invention relates to the processing of liquid radioactive waste containing radioactively labeled biological molecules. More specifically, this invention relates to the use of solid phase binders to remove radioactively labeled biological molecules from liquid radioactive waste solutions.

Abstract: An apparatus and method for treating materials that present disposal problems is provided. The treatment takes place within an aqueous stream and in an oxygen-deficient multiple zone system, and results in the thermal decomposition and/or separation of components within the treated material. The apparatus and method of this invention may be used for the treatment of non-hazardous and hazardous waste, including organic and inorganic compounds, radioactive materials, toxic compounds, binary chemicals (such as nerve gas) and heavy metals, prior to disposal.

Abstract: A practical method is described for preparation of radioactive ion-exchange resin for its disposal after the ion-exchange resin has become radioactive in the process of decontaminating radioactive water. Substantially nonradioactive material, which has been derived from the radioactive ion-exchange resin can be disposed of conventionally. The concentration allows corollary reduction of the volume of radioactive waste which must be handled in very costly ways. The radioactive ion-exchange resin and materials that react with the radioactive decaying atoms are heated under controlled atmospheres to (i) form nonvolatile chemicals that hold the decaying atoms, and (ii) under controlled conditions, depolymerize, vaporize, pyrolize, and otherwise decompose and remove nonradioactive components of the ion-exchange resin from the radioactive decaying atoms.

Abstract: A method of preferential removal of cesium cations from aqueous solutions containing other inorganic cations. Deltahaedral heteroborane anions are added to the solution to form a salt with the cesium cations which then precipitates from the solution. The remaining dissolved Cs-deltahaedral heteroborane anion salt is then quantitatively sorbed on active charcoal to remove it from the solution.

Abstract: The invention relates to the dissolving of plutonium and/or other radioactive elements in an aqueous solution by microwave heating.According to the invention, solid or liquid products containing plutonium and/or other radioactive elements are introduced into a container (7) containing an acid solution, comprising hydrofluoric acid and nitric solution, followed by the microwave heating of the solution containing these products using a chamber or tank (5) placed in a tight enclosure (1), which is supplied with microwaves by means of a coaxial cable or a waveguide (11) connected to the generator (9) located outside the enclosure.The solid products can be plutonium dioxide PuO.sub.2 or organic or mineral radioactive waste materials such as gloves, cellulose products, ion exchange resins, etc. The liquid products can be contaminated organic solvents such as tributyl phosphate in dodecane.

Abstract: A method of decontaminating the surface of a body carrying radioactive contaminants which comprises treating the surface with a decontaminant comprising a solution of tetrafluoroboric acid HBF.sub.4, treating the resultant liquor comprising decontaminant and dissolved species removed from the body surface with a first chemical agent which on reacting with dissolved species yields insoluble compounds and regenerated decontaminant solution, and characterized in that the regenerated decontaminant solution is further treated to cause removal of the first chemical agent from the decontaminant solution.

Abstract: A method of separating and purifying a spent solvent generated in a nuclear fuel cycle and containing a higher hydrocarbon and a phosphate. This method comprises applying to the spent solvent a pressure high enough for allowing the crystallization of the higher hydrocarbon to thereby crystallize the higher hydrocarbon, and separating under pressure a resulting solid mainly composed of the higher hydrocarbon from a remaining solution containing the phosphate in a higher concentration. The remaining solution may further be subjected to low-temperature vacuum distillation to separate the solution into the phosphate and a deterioration product thereof contained in the solution.