sup 137 Cs and (sup 131)I tracer studies on Zr/Na and Al/Na pilot plant calcine to evaluate thermal processes as calcine pretreatment options

摘要

The reason for performing volatility studies on pilot plant calcine is to determine the cesium, and iodine decontamination factors as a function of time, temperature, and calcine type. This report discusses separations processes which are being evaluated for ICPP calcine to reduce the high-level waste volume requiring disposal in a geological repository. Reducing the high-level waste volume may reduce disposal cost and conserve repository space. Several aqueous separation processes may be applicable in partitioning the high-level constituents (actinides and fission products). These processes require calcine dissolution in acid prior to actinide and fission product separation. Cesium may be a difficult element to separate from the dissolved calcine because of the solutions: Acidicity and complicated chemical matrix. Sodium, calcium, aluminum, and zirconium may interfere with cesium removal from the acidic or neutralized solution. Because of this, a thermal pretreatment option was evaluated in hopes of selectively removing cesium prior to calcine dissolution.