Borosilicate glass waste forms

Of these three processes, some have received more study than others. There have been a number of determinations of leach rates (step 1) particularly from borosilicate-glass waste forms (see, for example, 1, 3), but there has been minimal effort to deter-... 

Jercinovic, M. J. Ewing, R. C. 1987. Basaltic Glasses from Iceland and the Deep Sea Natural Analogues to Borosilicate Nuclear Waste-Form Glass. Swedish Nuclear Fuel and Waste Management Co, Stockholm, Technical Report JSS 88-01, 221 p. 

Waste-Form Stability. If they occur at all, solid state transformations in dry glass and UO2 matrices will be too slow under the temperature conditions of service to be observable in the laboratory at the same temperature. Here we need to extrapolate from high temperature laboratory conditions to low temperature service conditions. It will be desirable to develop an intimate knowledge of the processes of phase separation and devitrification of sodium borosilicate glasses at temperatures below the softening point by meticulous application of electron microscopic. X-ray crystallographic and other techniques. The glasses will contain inactive elements representative of the fission product... 

Zhao, D., Li, L., Davis, L. L., Weber, W. J. Ewing, R. C. 2001. Gadolinium borosilicate glass-bonded Gd-silicate apatite A glass-ceramic nuclear waste form for actinides. Materials Research Society Symposium Proceedings, 663, 199-206. 

Malow, G., Lutze, W. Ewing, R. C. 1984. Alteration effects and leach rates of basaltic glasses implications for the long-term stability of nuclear waste form borosilicate glasses. Journal of Non-Crystalline Solids, 67, 305-321. 

Jercinovic, M. J., Kaser, S. Ewing, R. C. 1989. Observations of surface layers formed on basaltic and borosilicate glass 6 month and 1 year MIIT experiments. In Proceedings of the Workshop on Testing of High Level Waste Forms under Repository Conditions. EUR 12017 EN, the Commission of the European Communities, 183-191. 

The fissured basalt cores and bentonite were altered by placing them in an autoclave under simulated groundwater at 320°C for 30 and 60 days to simulate 1000 y and 2000 y aging, respectively The waste-form wafers for both experiments were aged in the same manner by treating them for 17 days in saturated steam at 340°C The details of these procedures and the rationale for their use have been published previously (7). The effects of saturated steam on borosilicate glass were discussed in a recent publication (8) ... 

Of the other forms, none seems to be entirely satisfactory or compatible with SRP waste at the present stage of development. Phosphate glass devitrifies and becomes more leachable borosilicate glass is not miscible with sulfate, forming a highly leachable separate phase asphalt is flammable, particularly when mixed with manganese dioxide and... 

Vitrification technology for production of waste forms is the most developed and is only presently utilized at an industrial scale. Currently actual HLW from SNF reprocessing is being vitrified with production of borosilicate glass in France and UK using an inductively-heated (200-300 kHz) metallic (Inconel-690) melter [44,45]. Replacement of the induction-heated metallic melter by a cold-crucible melter is being considered [46]. In the USA and Russia Joule-heated ceramic melters are implemented for HLW vitrification in borosilicate or phosphate [24,47-50] glasses. By the end of 2000 the total amount of vitrified radioactive waste in the world was about 10 000 MT [43]. 

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