Study on removal of iodine from atmosphere by spray, (4). Removal of iodine by reactive spray

Washout removal of iodine from atmosphere by reactive spray was studied with the use of small-scale steel vessels simulating containment. The washout experiments in the range of 25° to 80℃ were performed under normal steady state spray, while runs at 100° to 150℃ utilized spray accompanied by cooling, the steam pressure being that of equilibrium for the temperature of the experiment. The iodine removal rate was evaluated by varying the gas phase concentration which was determined by thiosulfate titration. It was found as a result that the washout rates of iodine by a spray of 0.1 to 1 M NaOH solution were thirty to seventy times as fast as by plain city water, and that the rates were independent of temperature. A similar degree of enhancement was observed with sodium thiosulfate solution. An even greater effect was obtained with sodium sulfite solution. The rate of iodine washout was found to be expressible by first order equation, which suggested gas film controlled absorption as the mechanism of iodine absorption in the liquid drops. (author)