Ceramic waste process

Performance assessments are predictions of radioactivity releases, the rate of transfer of contaminants through various media, and the potential for hazard to the pubHc. These are based on a combination of experimental data obtained in the process called site characterization and detaded computations about radionuchdes and their effects. The progressive attack on the metal or ceramic waste container, the diffusion of water into the waste form, the leaching of the radioactive compounds, diffusion out, and washing away of radionuchdes are all considered. 

The use of inorganic ion exchangers to solidify liquid radioactive waste followed by pressure sintering to produce a ceramic waste form appears to be a viable alternative to calcina-tion/vitrification processes. Both the process and waste form are relatively insensitive to changes in the composition of the waste feed. The stability of the ceramic waste form has been shown to be superior to vitrified wastes in leaching studies at elevated temperatures. Further studies on the effects of radiation and associated transmutation and the influence of temperature regimes associated with potential geologic repositories are needed for a more definitive comparison of crystalline and amorphous waste forms. 

Zakrzewska-Trznadel, G. and Harasimowicz, M., Application of ceramic membranes for hazardous wastes processing Pilot plant experiments with radioactive solutions, Desalination, 162, 191, 2004. 

However, all the ceramic technologies were tested on lab- or bench-scale basis in inactive variants and their suitability to actual HLW and actinide waste processing has not yet been demonstrated. 

BM Wise, DJ Veltkamp, NL Ricker, BR Kowalski, SM Barnes, and V Arakali. Application of multivariate statistical process control (M-SPC) to the West Valley slurry-fed ceramic melter process. In Proceedings of Waste Management 91, pages 169-176, Tucson, AZ, 1991. 

Sato et al. studied the removal efficiency of four pot-type water purifiers, two of which consisted of activated carbon and ceramic hollow fibers [62]. Iodide, iodate, cesium, and barium were removed with efficiencies of 85%, 40%, 75%-90%, and 85%, respectively, by all purifiers. In another study, Zakrzewska-Trznadel et al. have presented work concerning liquid waste treatment, in particular, the processing of low- and medium-level radioactive waste treatment [63]. After discussing various methods, they concluded that RO and tvSm ceAIseeded UF are the most basic methods to be applied. The other methods such as MF, MD, and NF can be considered as supplementary methods for the preliminary stages of raw radioactive waste processing or the final processing of the effluents. They also proposed a hybrid process, in which RO, UF, and MD are combined, based on their experiences with each individual process. 

The treatment of spent nuclear fuel by the IFR process results in two HLW forms ceramic and metal. The ceramic waste form stabilizes the active FPs (alkali, alkaline earth, and rare earths) and the metal waste consists of stainless steel cladding and, fuel matrix material... 

The ceramic waste form is a glass-bonded sodalite produced from the thermal conversion of zeolite. The salt is removed from the electrorefiner and initially ground to a powder. This powder is mixed with zeolite at 500 °C and is occluded into the zeolite structure. This salt-loaded zeolite is then mixed with glass frit and is transferred to a furnace where if is heated to 850 °C. During this process, the zeolite is converted to sodalite and a ceramic is formed (Goff et al., 2005 Marsden et al., 2005). 

Simpson, M.F. et al. 2001. A description of the ceramic waste form production process from the demonstration phase of the electrometallurgical treatment of EBR-II spent fuel. Nuclear Technology 134(3) 263-377. 

Metallacarboranes. These are used in homogeneous catalysis (222), including hydrogenation, hydrosilylation, isomerization, hydrosilanolysis, phase transfer, bum rate modifiers in gun and rocket propellants, neutron capture therapy (254), medical imaging (255), processing of radioactive waste (192), analytical reagents, and as ceramic precursors. 

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