Tritium leakage from recycling path

An idea of liquid waste recycling was studied on the basis of wet treatments in an attempt to reduce tritium release from a spent fuel reprocessing plant by the purex method. In this system, tritium leakage from a recycling path is one of the most important items determining the decontamination factor. The co-decontamination process in a recycling path was approximated by extraction system with five components, i.e., UO2(NO3)2-TBP-Dodecane-H2O-HNO3, and tritiated water leaked into organic phase was estimated from the amount of dissolved water. As the result, the leakage of tritiated water from co-decontamination process was found to be about 0.4%, using the liquid composition of the purex method based on the PNC reprocessing flowsheet. In conclusion, the practical decontamination factor of tritium is estimated to be below 50. (auth.)