Study on Probabilistic Safety Analysis Method of Spent Fuel Reprocessing Facilities

Probabilistic safety analysis (PSA) method is a systematic analysis method based on probability theory. Based on the PSA method, the relationship and interaction between various factors in a large and complex system can be recognized clearly, and the accident scenarios can be modeled correctly. After years of development, PSA has gradually become an important tool for evaluating the safety of nuclear power plants, and has been widely used. For the safety analysis of spent fuel reprocessing facilities, deterministic safety analysis methods are still mostly used. It is beneficial to introduce quantitative probabilistic safety analysis methods into spent fuel reprocessing facilities. For spent fuel reprocessing plants, there are many features which are totally different from nuclear power plants. Therefore, we are supposed to establish a new framework for PSA of spent fuel reprocessing plants. In this study, the spent fuel reprocessing facilities safety evaluation methods and the PSA method were investigated, based on the risk characteristics of spent fuel reprocessing facilities, every technical element of PSA method was adjusted. We studied the possible problems existing in the application of PSA method and proposed corresponding solutions, and then established a PSA method system suitable for spent fuel reprocessing facilities. Finally, we used PSA method to evaluate the safety of the selected typical processes of spent fuel reprocessing facilities and got the analysis result which is useful for practical application.