New pool scrubbing correlations based on reliable data

The removal of aerosol particles and vapors in gas bubbles moving through a water pool is known to be an efficient means to reduce source term to the environment during severe accidents, as it happened in the Fukushima Daiichi accident. Based on the experimental data reported until 2016, this paper analyses and dis-cusses the trends of DF (Decontamination Factor) with injection depth, particle size, gas flowrate and steam fraction. The analysis done indicates that the depth effect on DF depends on particle size and the injector diameter. As for particle size, the bigger the particle, the higher the DF (under the conditions experimentally investigated in the selected projects); however, a sound correlation cannot be set as such dependence is strongly dependent on other variables too. The effect of submerged structures on DF has been shown to be minor. When coming to flowrate or steam content, even though the effect is observed, correlations are just too inaccurate to be given any quantitative credit.