Full-Scale Cold Crucible Test on Vitrification of Savannah River Site SB4 HLW Surrogate

摘要

The full-scale cold crucible test on vitrification of sludge batch 4 (SB4) Savannah River Site HLW surrogate using a 418 mm inner diameter stainless steel crucible was carried-out for 66 hrs. Commercially available Frit 503-R4 (8 wt.% Li(sub 2)O, 16 wt.% B(sub 2)O(sub 3), 76 wt.% SiO(sub 2)) was used as a glass forming additive at a calcine to frit ratio of 1:1 (50 wt.% calcine, 50 wt.% frit). Two portions of slurry prepared from frit and mixture of chemicals simulating waste in amount of (approx.) 750 kg and from frit and waste surrogate prepared by the SRT-MST-2007-00070 procedure in amount of (approx.) 1,300 kg with water content of (approx.) 27 and (approx.) 50 wt.%, respectively, was processed and (approx.) 875 kg of the vitrified product in total ((approx.) 415 + 460 kg) was obtained. Average parameters were as follows: vibration power - 121.6 to 134.1 kW, feed rate (capacity) - 25.1 to 39.8 kg/hr, glass pour rate (productivity) - 14.0 kg/hr specific energy expenses for feed processing - 4.8 to 3.4 kW x hr/kg, specific energy expenses for glass production (melting ratio) - 8.7 to 9.6 kW x hr/kg, specific glass productivity - 2453 kg/(m(sup 2) x d). The product was composed of major vitreous and minor spinel structure phases. No nepheline phase was found. Average degree of crystallinity was estimated to be (approx.) 12 vol.%. Cesium was found to be the most volatile component (up to (approx.) 60 wt.% of total). Lithium, sodium and boron are less volatile.