Rigorous Tritium Wet Scrubber Column Modeling and Design

The rigorous steady-state equilibrium stage Tritium Wet Scrubber Column model has been developed. The model includes the six water isotopologues H₂O, HDO, HTO, D₂O, DTO, and T₂O; heat balance; and packing pressure drop. Heat balance is particularly important in wet scrubber calculations due to evaporative cooling of air with less than 100% relative humidity. Evaporative cooling is generally beneficial, but freezing is possible with very cold dry air, making it important to understand operating limits. The pros and cons of precooling and saturation of the airstream are discussed. The Tritium Wet Scrubber Column model has been applied to scrubbing airstreams containing tritiated light water vapor and for tritiated heavy water vapor in CANDU® heavy water applications. Deuterium and tritium are recovered at slightly different efficiencies, and because of differences in the latent heat of vaporization for H₂O and D₂O, liquid and vapor compositions affect the column heat balance. Case studies are presented for tritiated light water vapor air detritiation and also for tritiated heavy water vapor air detritiation to provide guidance for design. Further, practical aspects of the wet scrubber column construction and operation are discussed.