Extrapolating Kd or Rd from Breakthrough Curves of Cesium Cations Transporting Through a Soil Column
Cesium-137 is a radioactive element that could be released within the byproducts of a nuclear power plant. Breakthrough curves obtained from a column test are commonly used to simulate the in situ transport process in case of a leakage, and to obtain key parameters such as coefficient of distribution (Kd) and retardation factor (Rd). Four existing methods, which vary by complexity, theoretical soundness and easiness to implement, were used to extract Kd and Rd values. Breakthrough curves of cesium cation migrating through saturated and unsaturated soil column from previous literature were analyzed and compared. Preliminary results suggest that in fully saturated condition, the closeness of Rd values derived by above-mentioned methods decrease as the Peclect number decreases. In unsaturated condition, however, immobile water around the dead end pores could induce different results of one-region model and two-region model.
KeywordsBreakthrough curve Retardation factor Coefficient of distribution Cesium
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