Calculation and analysis on radioactive nuclide removal ability for spray system under the marine reactor severe accident

The release of airborne radioactive substances is greatly harmful to reactor operators under the condition of severe accident. Using the MELCOR code which is serious accident integration calculation program, We selects the typical LOCA to evaluate engineering removal ability for spray system and study the spray conditions influence on airborne radioactive material removal by changing the parameters of spraying. The results showed that changing the input threshold of spray system would make the radionuclide release amount change under the condition of the same spray. spray system input can reduce gross of halogen, alkali metal in airborne to some extent, but on inert gas removal ability is limited. The decrease of the droplet diameter would strengthen the remove of airborne radioactive matter. The pH value changing of spraying agent had no efficiently effect on removal efficiency for airborne radioactive substances. (authors)