Abstract
In Japan, a preliminary safety assessment for geological isolation of TRU waste has reported that the rate of radioactive exposure can be controlled by radioactive iodine (I-129). In order to decrease the rate of radioactive exposure, the HIP (Hot Isostatic Pressing) solidified method has been developed for an iodine adsorbent waste (silver loaded silica gel).
The HIP method can manufacture a solidified waste, which don't separate and volatilize I-129 from iodine filter waste. For the solidified waste manufactured at 750°C (treatment temperature), 100MPa (treatment pressure), the base material changed from silica gel to quartz which is high density and high strength. The grain size grew up and became a few-10μm in diameter. Iodine was solidified between quartz grains as AgI on physically stable form.
The test and estimation result for iodine-solidified structure of the HIP "rock" solidified waste show on this report.
