Experiments for liquid/vapor equilibrium of multicomponent nitrate solution

Boiling accidents of reprocessed liquid wastes at fuel reprocessing facilities are postulated to occur by the loss of cooling function for waste storage tanks due to a long-term total loss of AC power. Some amounts of radioactive materials could be released from facilities by vapor flow from a boiling liquid waste storage tank. Thermal-hydraulic behavior of water and nitric acid vapor and aerosol behaviors in compartments of facility building are needed to be analyzed for assessing amount of released radioactive materials to outside of facilities. The amount of water and nitric acid vapor, which is one of key parameters to estimate the duration time of evaporation to dryness and the amounts of radioactive materials transferring from liquid to vapor phase, is calculated based on the liquid/vapor equilibrium data of liquid wastes. This report describes details and results of experiments to obtain the liquid/vapor equilibrium data of multicomponent nitrate solution simulating reprocessed liquid wastes. (author)