Abstract:
A method of waste stabilization by mineralization of waste material in situ in a treatment container suitable or treatment, transit, storage and disposal. The waste material may be mixed with mineralizing additives and, optionally, reducing additives, in the treatment container or in a separate mixing vessel. The mixture is then subjected to heat in the treatment container to heat-activate mineralization of the mixture and form a stable, mineralized, monolithic solid. This stabilized mass may then be transported in the same treatment container for storage and disposal.
Abstract:
A method including a combination of intermediate storage and reprocessing is utilized to process spent nuclear fuel (SNF) and thereby effect a disposition of that SNF within a period of 300 years. The method includes five or more years of pool water storage wherein ninety-nine percent (%) of the fission wastes energy decays. The waste material is then stored in an air convention storage facility, before processing to separate Cesium and Strontium from the waste is effected. This air convection cooling may be done in convection air-cooled concrete casks. During 50 years of convection air-cooled storage the energy contained in the waste material declines another one half %. Thereafter, at any point the SNF is processed to sufficiently separate 99.999% of the 97% of actinides (approximately 95% U238 uranium, 1% U235 uranium, and 1% Pu239 plutonium) from the 3% fission wastes. Again, it is only necessary to provide approximately 99.999% separation of the TRU's (transuranic waste) from the fps (fission products)—more specifically, sufficient separation so that the residual fps are contaminated with less than 100 nCi/g TRU's, as defined in the Class C regulations—10CFR61. The separated actinides and transuranics are thereafter utilized in the manufacture of MOX (mixed oxide) or fast burner reactor fuel pellets for future reactor fuel. The remaining fission wastes, containing Cesium and Strontium, are then placed into containers and subsequently put into dry storage for the remainder of around 300 years, where most of the remaining half % of its radiation energy material, i.e., Cesium and Strontium decays. Thereafter this fission waste is put into a low level Class-C nuclear waste repository, which may include leaving them in the intermediate storage facility that is also designed to accommodate and dispose Class C waste.
Abstract:
The present invention relates to a nuclear waste disposal apparatus, a method of manufacturing the same, and a method of installing the same. The apparatus is manufactured by packing nuclear waste into a vessel, installing the vessel into a ring-shaped elastic body such as a discarded tire used on a truck or a large-sized bus, covering the vessel storing the nuclear waste therein with high-strength reinforced concrete, and installing pieces of structural steel in a space of the elastic body so that the apparatus can endure heavy loads and natural disasters such as earthquakes.
Abstract:
A method for the encapsulation of fine particulate materials includes treating these materials with a microfine hydraulic inorganic filler which, typically, includes a cementitious material, such as Portland Cement. The filler is ground to a much smaller particle size than is normally used in the production of a grout and is provided in the form of an aqueous composition for the treatment of the fine particulate materials by pumping under pressure through these materials such that they become intimately encapsulated. The method is particularly applicable to the treatment of waste materials and, most particularly, waste materials, which are encountered in the nuclear industry.
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 suspension containing a sulfate, hydroxide, chloride, fluoride and/or silicate source and a phosphate anion. 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:
A method for forming a radiation-absorbing barrier around a radioactive component by flowing a radiation-absorbing cement grout into a container which encloses the component. The radiation-absorbing cement grout comprises a cement slurry, a finished foam material, a bentonite gel, and a radiation-absorbing metal constituent.
Abstract:
The present invention discloses a method of treating lead bearing process materials and lead toxic hazardous wastes. The invention relates to treatment methods employed to chemically convert leachable lead in lead bearing solid and liquid waste materials to a non-leachable form by mixing the material with lime, gypsum and/or phosphoric acid. The solid and liquid waste materials include contaminated sludges, slurries, soils, wastewaters, spent carbon, sand, wire chips, plastic fluff, cracked battery casings, bird and buck shots and tetraethyl lead contaminated organic peat and muck. The present invention discloses a process comprising a single step mixing of one or more treatment additives, and a process comprising a two step mixing wherein the sequence of performing the steps may be reversible. The present invention provides a new way of treating a universe of lead contaminated materials at any pH.
Abstract:
A method for forming a radiation-absorbing barrier around a radioactive component by flowing a radiation-absorbing cement grout into a container which encloses the component. The radiation-absorbing cement grout comprises a cement slurry, a finished foam material, a bentonite gel, and a radiation-absorbing metal constituent.
Abstract:
The invention relates to a process for the conditioning of radioactive waste using silicated apatites as the confinement matrix. This process consists of incorporating the waste (1) into a phosphosilicated apatite-based confinement matrix (3) e.g. complying with the formula: M.sub.t Ca.sub.x Ln.sub.y A.sub.z (PO.sub.4).sub.u (SiO.sub.4).sub.6-u X (I) in which M is an alkali metal, Ln a rare earth, A an actinide, X is S.sup.2-, 2F.sup.-, 2Cl.sup.-, 2Br.sup.-, 2I.sup.- or 2OH.sup.- and u is between 0 and 6.
Abstract:
The present invention relates to a method of solidifying radioactive waste with cement, comprising forming a mixture comprising water, a hydrophilic material and cement substantially non-shrinkable or expansible with respect to volume change upon hardening, mixing said mixture with the radioactive waste, followed by hardening to form a solid body.The present invention enables the formation of a compact solid body having voids, such as capillary voids, of reduced volume, which makes it possible to reduce the leaching rate of hazardous materials. Further, since no shrinkage accompanies hardening, no tensile stress occurs in the cement surrounding minute waste particles within the hardened material, thereby enabling a decrease in the strength of the solid body to be minimized. This in turn enables an increase in the amount of packing of waste. Prior addition of a hydrophilic material enables the cement fluidity before hardening to be maintained even after complete absorption of water by a water absorptive waste. This is extremely advantageous in carrying out hardening.