MODELING VOLATILIZATION OF TRICHLOROETHYLENE FROM A DOMESTIC SHOWER SPRAY - THE ROLE OF DROP-SIZE DISTRIBUTION

The factors affecting the volatilization of trichloroethylene from a shower spray were assessed and modeled as a function of the distribution of drop sizes. For the 10 L/min shower-water flow system, the measured drop sizes were smaller and initial velocities greater than those for the 5 L/min system. Log-probit plots indicate a bimodal distribution of drop sizes for each flow rate. Three models for internal mass transfer from drops were assessed to determine which best predicted shower emissions. A penetration theory model applied to oscillating drops, an eddy diffusion model, and a model for mass transfer restricted to a thin liquid film surrounding the drops was compared to data on volatilization from drops collected at different heights in the shower spray. The former two models fit the data. It was also observed that volatilization from water at the bottom of the shower was substantial.