Waste recovery from high-level

Figure 1. Flowsheet for Am-Cm recovery from high-level waste (1WW) solutions (1). For a list of compositions and flow rates of the process streams see References 4 and 5.

Figure 2. Flowsheet for Am + Cm recovery from high-level waste solutions (18)...

Goldberg [44], surprisingly high concentrations were detected for the former 16, 000 Bq/kg, for the latter 43,000-46,000 Bq/kg. All these data indicate that technetium should be carefully recovered in reprocessing plants. The systematic recovery of technetium together with elements of the platinum group from high level wastes have been discussed by Kubota [45],... 

Chitnis, R.R., Wattal, P.K., Ramanujam, A. et al. 1999. Recovery of actinides extracted by TRUEX solvent from high-level waste using complexing agents II. Counter-current studies. J. Radioanal. Nucl. Chem. 240 (3) 727-730. 

Filippov, E.A., Dzekun, E.G., Nardova, A.K. Mamakin, I.V., Gelis, V.M., Mityutin, V.V. Application of crown-ethers and ferrocyanide-based inorganic materials for cesium and strontium recovery from high-level radioactive wastes. In Proc. Symp. Waste Management, Tucson, AZ, Vol. 2, 1992, pp. 1021-1024. 

Filippov, E. A., Dzekun, E. G., Nardova, A. K., Mamakin, I. V., Gelis, V. M., and Milyutin, V. V. Application of Crown Ethers and Ferrocyanide-Based Inorganic Material for Cesium and Strontium Recovery from High-Level Radioactive Wastes, Proc. Waste Management 92, Tucson, Arizona, U.S.A., Mar. 1-5, 1992, pp. 1021-1025. 

Ansari, S.A., Mohapatra, P.K., and Manchanda, V.K. 2009. Recovery of actinides and lanthanides from high level waste using hollow fiber snpported liquid membrane with TODGA as the Carrier. Ind. Eng. Chem. Res. 48 8605-8612. 

By-Products. The PUREX process is efficient at separating uranium and plutonium from everything else in the spent fuel. Within the high level waste stream are a number of components which have, from time to time, been sufficiendy interesting to warrant their recovery. The decision to recover a particular isotope is usually based on a combination of market incentives and desired waste reduction. 

Rizvi, G.H. et al.. Recovery of fission product palladium from acidic high level waste solution, Sep. Sci Technol, 31(13), (1996), ppI80S-1816. 

Table III. Composition of High-Level Waste from Reprocessing LWR Fuel, and Actinide Recovery Factors Required"...

The americium and curium isotopes formed during irradiation of nuclear reactor fuels are diverted into the high-level waste (HLW) stream during fuel reprocessing. The HLW is thus the biggest potential source for these elements, and R+D activities to develop a process for the recovery of Am and Cm from HLW were started in 1967. A major condition was that the process to be developed must not essentially increase the waste amount to be processed further, must not use strongly corrosive reagents, and must be compatible with the final waste solidification procedure. 

A modification of the Redox process, the U-hexone process, was used at the Idaho Chemical Processing Plant of the U.S. AEC, to recover highly enriched uranium from U-A1 alloy fuel elements irradiated in the Materials Testing Reactor. The aluminum nitrate needed as salting agent was provided when the fuel was dissolved in nitric acid. The plutonium content of the fuel was too low to warrant recovery. Plutonium was made trivalent and inextractable before solvent extraction and thus routed to the aqueous high-level waste. 

Nitric acid recovery. Aqueous nitric acid is recovered from the high-level waste evaporator, from recycle streams 15 and 25, and from nitrogen oxides in dissolver off-gases as described in Secs. 4.11 and 4.13,... 

Rl. Richardson, G. L. Technologies for the Recovery of the Transuranium Elements and Immobilization of Non-High-Level Wastes, Proceedings of the International Symposium on the Management of Wastes from the LWR Fuel Cycle, Denver, 1976, Report CONF-76-0701, p. 289. 

To rather selectively separate pertechnetate, with more than 90 % yield, from solutions of acid fission products it was proposed to use finely divided cadmium sulphide. The overall yield of the radionuclide pure c, finally extracted as [(C(,H5)4As TcC)4, was 68 % [182,183]. In addition, activated carbon was used to efficiently separate pertechnetate from high-level liquid waste. Distribution coefficients of more than 500 were observed when pertechnetate was separated with activated carbon from a 2 M HNO3 solution [184]. Effective separation and recovery of Tc04 from contaminated groundwater with activated carbon have been reported very recently [185. ... 

Kandwal, R, Ansari, S.A., and Mohapatra, P.K. 2011. Transport of cesium using hollow fiber supported liquid membrane containing calix[4]arene-bis(2,3-naphtho)crown-6 as the carrier extractant Part II. Recovery from simulated high level waste and mass transfer modeling. J. Membr. Sci. 384 37 3. 

Remediation of high level waste (HLW) stream by using a SLM TODGA Quantitative recovery of Am(lll), Eu(lll), Pu(lV), Np(lV) and U(V1) from simulated HLW No transport of monovalent cation like Cs(l) Transport rates marginally affected by the presence of structural materials Linear decrease of permeability by increasing the radiation dose over 0.46 MGy Ansari et al. (2007)... 

Studies designed to improve the determination of environmental contaminants will continue to provide refinements and improvements in the determination of acrylonitrile. The current high level of activity in supercritical fluid extraction of solid and semisolid samples should yield improved recoveries and sensitivities for the determination of acrylonitrile in solid wastes, and the compound should be amenable to supercritical fluid chromatographic analysis. Immunoassay analysis is another area of intense current activity from which substantial advances in the determination of acrylonitrile in environmental samples can be anticipated (Vanderlaan et al. 1988). 

High-level radioactive defense waste solutions, originating from plutonium recovery and waste processing operations at the U.S. Department of Energy s Hanford Site, currently are stored in mild steel-lined concrete tanks located in thick sedimentary beds of sand and gravel. Statistically designed experiments were used to identify the effects of 12 major chemical components of Hanford waste solution on radionuclide solubility and sorption. 

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