The aim of the study was to assess Cs+ ions transport phenomena from
solidified spent ion exchange resin by mathematical modeling. The
experimental results comparison was obtained by Hespe?s Standard Leaching
Method. For the leaching prediction rate as a time function diffusion and
semi-empirical models were used. Due to the presence of spent ion exchange
resin, the cement matrix absorbed a larger amount of water, swelled, and
degraded. This phenomenon caused a significantly lower value of mechanical
resistance to pressure. Also, through the increase of bentonite and zeolite
content, the cement matrix decreased its mechanical resistance. The
retention of cesium ions in the cement matrix was low and they were leached
during the early phase of the investigation. The diffusion coefficient, De,
decreased by three orders of magnitude with the addition of zeolite and
bentonite in the cement matrix. Linear regression of experimental Cs+
leaching results under static conditions displayed that the semi-empirical
parameter K3 absolute values were one to two orders of magnitude lower than
the absolute values of the parameters K2 and K1. Therefore, the contribution
of matrix dissolution to the total radionuclides transport was irrelevant to
the prevailing share of diffusion and surface washing processes.
Mathematical modeling of Cs+ transport phenomena from solidified spent ion exchange resin
