A thermal model of the immobilization of low-level radioactive waste as grout in concrete vaults

Salt solution, from radioactive waste generated by the production of plutonium and tritium in nuclear reactors at the Savannah River Site, will be mixed with cement and flyash/slag to form a grout which will be poured into above ground concrete vaults. The curing process is exothermic, and a transient thermal model of the pouring and curing process is herein described. A peak temperature limit of 85 °C for the curing grout restricts the rate at which it can be poured into a vault. The model is used to optimize the pouring.