Solidification, high-level waste

Comparison of the Radionuclide Activity-in Effluent from Titanate Solidification Process with the Activity in the High Level Waste Feed Solution... 

The Zircaloy Conversion Process (24, 25, 26) is a concept whereby one waste stream, Zircaloy fuel hulls, can be utilized in the stabilization of a second waste stream. The process flowsheet which is conceptual in nature, details the steps required to convert the fuel hulls to sodium zirconate to be used in the solidification of liquid high level waste. 

Another step in our program was to survey the literature and evaluate the technology of solid waste forms developed elsewhere (I) (Table V). The forms that have been used for solidification of intermediate level as well as high-level waste have been included in the table because the low power density of SRP waste might make these forms applicable. 

G. L., McKee, R. W., Blasewitz, A. G., Waste Solidification Program Summary Report, Vol. II, Evaluation of WSEP High-Level Waste Solidification Process, BNWL-1667, July 1972. 

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. 

Concentrated, denitroted high-level wastes, to storoge and eventual solidification 2-4M HNO3... 

Tabk 11.11 Summary of principal high-level waste solidification proc esses being developed in the Western world... 

Solidification. In principle, any solid that contains firmly bound water may be suitable as a solidification form for HTO. This includes drying agents, such as silica gel, molecular sieves, and calcium sulfate, as well as hydraulic cement and organic polymers. Most experience is available with cement, which has been used to solidify non-high-level waste for quite a while. 

Blasewitz, A. G., et al The High Level Waste Solidification Program, Proceedings of the Management of Radioactive Wastes from Fuel Reprocessing, Paris, 1972, Report CONF-721107, Mar. 1973, p. 615. 

Clelland, D. W., et al. A Review of European High-Level Waste Solidification Technology, Proceedings of the International Symposium on the Management of Wastes from the LWR Fuel Cycle, Denver, 1976, Report CONF-76-0701, p. 137. 

Releases from the nuclear fuel cycle may occur during reactor operations, nuclear fuel reprocessing, UFg conversion, uranium enrichment, uranium fuel fabrication, high-level waste solidification, high-level and low-level waste disposals. The enrichment process, with a significant aimual release through liquid discharges to the sea, is considered as the key contributor. So far, the total release of Tc to the... 

HLW (high level waste). The radioactive liquid containing most of the fission products and actinides present in spent fuel — which forms the residue from the first solvent extraction cycle in reprocessing — and some of the associated waste streams this material following solidification spent fuel (if it is declared a waste) or any other waste with similar radiological characteristics. Typical characteristics of HLW are thermal powers of about 2 kW/m and long lived radionuclide concentrations exceeding the limits for short lived waste [2]. 

Demine, A. V., Krylova, N. V., Poluektov, P. P., Shestoperov, I. N., Smelova, T. V., Gorn, V. F. Medvedev, G. M. 2001. High level liquid waste solidification using a cold crucible induction melter. Materials Research Society Symposium Proceedings, 663, 27-34. 

The high-level radioactive liquid wastes are stored in stainless steel 300,000-gal tanks located in underground concrete vaults pending their solidification in the Waste Calcining Facility (WCF). At present the liquid waste is stored for less than four years and is dependent in part on the rate of calcination and rate of waste generation. The tank farm consists of eleven 300,000-gal tanks and four special tanks of 30,000 gal each. 

Solidification of High-Level Liquid Wastes in the Waste Calcining Facility (WCF)... 

Solidification and Storage of Hanford s High-Level Radioactive Liquid Wastes... 

It should be noted that the canister may add considerably to the durability of a high-level radioactive waste package. Often it may be easier to achieve a higji degree of sophistication with a nonradioactive canister material than with a highly radioactive solidification product. 

In 1976 pilot-scale testing with simulated commercial high- and medium-level waste feedstock composition was conducted to demonstrate the feasibility of the process for this type of waste. Currently expected commercial waste compositions do not seem to present major problems in fluidized-bed calcination [M2]. A conceptual flow sheet for fluidized-bed solidification of commercial waste is shown in Fig. 11.16. 

Ewest, E., and H. W. Levi Evaluation of Products for the Solidification of High-Level Radioactive Waste from Commercial Reprocessing in the Federal Republic of Germany, Proceedings of the Mane ement of Radioactive Wastes from the Nuclear Fuel Cycle, vol. 2, International Atomic Energy Agency, Vienna, 1976, p. 15. 

Kushnikov V.V., Matyunin Yu.L, Krylova N.V., On the behavior of Alpha Radionuclides upon Solidification of High Level Liquid Wastes, Atomic Energy,... 

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