Analytical Studies of Elemental Iodine Removal by Sprays in the Donald C. Cook Nuclear Plant

A computerized mathematical model has been developed which treats the process of iodine removal from the atmosphere of a multivolume nuclear reactor containment by aqueous sprays under simulated accident conditions. The model is an extension of an earlier work and consists of a set of simultaneous linear first-order differential equations that are solved time incrementally. The rate coefficients are calculated internally and take into account the effects of spray solution chemistry, liquid phase mass transfer resistance, system temperature, spray drop coalescence, spray coverage, spray impingement on internal obstructions, and spray solution recirculation. Results of parameter variation studies with the model reveal that liquid phase mass transfer resistance effects are more important than spray loss mechanisms in controlling iodine removal rates. Comparison of computed predictions with results of experimental spray studies shows close agreement with respect to initial iodine removal rates.