Results of intermediate-scale hot isostatic press can experiments

Radioactive high-level waste (HLW) has been managed at the Idaho Chemical Processing Plant (ICPP) for a number of years. Since 1963, liquid HLW has been solidified into a granular solid (calcine). Presently, over 3,800 m{sup 3} of calcine is stored in partially-underground stainless steel bins. Four intermediate- scale HLW can tests (two 6-in OD {times} 12-in tall and two 4-in OD {times} 7-in tall) are described and compared to small-scale HIP can tests (1- to 3-in OD {times} 1- to 4.5-in tall). The intermediate-scale HIP cans were loaded with a 70/30 calcine/frit blend and HIPped at an off-site facility at 1050{degrees}C; and 20 ksi. The dimensions of two cans (4-in OD {times} 7-in tall) were monitored during the HIP cycle with eddy-current sensors. The sensor measurements indicated that can deformation occurs rapidly at 700{degrees}C; after which, there is little additional can shrinkage. HIP cans were subjected to a number of analyses including calculation of the overall packing efficiency (56 to 59%), measurement of glass-ceramic (3.0 to 3.2 g/cc), 14-day MCC-1 leach testing (total mass loss rates < 1 g/m{sup 2} day), and scanning electron microscopy (SEM). Based on these analyses, the glass-ceramic material produced in intermediate-scale cans is similar to material produced in small-scale cans. No major scale-up problems were indicated. Based on the packing efficiency observed in intermediate- and small-scale tests, the overall packing efficiency of production-scale (24-in OD {times} 36- to 190-in tall) cans would be approximately 64% for a pre-HIP right-circular cylinder geometry. An efficiency of 64% would represent a volume reduction factor of 2.5 over a candidate glass waste prepared at 33 wt% waste loading