Ion exchange columns for rapid treatment of nuclear medical radioactive wastewater: Study on the adsorption distribution and radiation protection of 131I− nuclides

Abstract With the rapid development of nuclear medicine, efficient treatment of nuclear medical radioactive wastewater is particularly important. This study simulated the dynamic adsorption behavior of 131 I − on an ion exchange column based on COMSOL Multiphysics. Combined with the MCNP6 radiation protection design, the distribution pattern of radionuclides and key influencing factors during the wastewater purification process were explored. The results show that: (1) the adsorption of 131I in the ion exchange column is distributed in an axial gradient, with the bottom (inlet) being saturated first, and the adsorption efficiency is significantly affected by the initial concentration and flow rate. (2) based on the Elovich adsorption model, the adsorption rate of the ion exchange column decreases with time. (3) after the ion exchange column is saturated, a 10–13 mm lead shielding layer can effectively reduce the gamma radiation to a safe level. This study provides a theoretical basis for the saturation replacement of ion exchange columns and the radiation protection design of deep purification equipment for nuclear medical wastewater.