Investigation of iodine removal efficiency in a venturi scrubber using mass transfer model for CFD

Abstract

Filtered containment venting system (FCVS) is important for the ultimate safety of a nuclear power plant owing to its use in containment pressure reduction in case of severe accident. It vents a portion of containment air after removal of harmful radioactive products including iodine through venturi scrubber. The purpose of this research was to develop a mass transfer model for estimation of performance of a venturi scrubber for removal of elemental iodine using Computational Fluid Dynamics. A mathematical model for transfer of iodine from air to water was developed based on two film theory of mass transfer and experimentally validated. Simulations were performed for self-priming non-submerged circular venturi scrubber using Fluent and the results were compared with experimental ones. Experimental data was used for validation in which an aqueous solution of sodium hydroxide and sodium thiosulfate was used as scrubbing solution for removal of iodine. For simulation, only water was used instead of scrubbing solution for simplicity. Euler-Euler approach was used for two-phase modeling and realizable k-epsilon model was used for turbulence modeling. The results obtained from simulations had a good match with the experimental ones.