Abstract: With the rapid growth of nuclear power industry in China, the quest for nuclear fuel reprocessing industry is getting stronger. In order to satisfy the quest for the nuclear emergency which is necessary for the safety development of nuclear fuel reprocessing industry and supply the evidence for nuclear emergency response and decision in nuclear fuel reprocessing plants. This paper aims at organic phase fire accident of 1A column which is a design basis accident in nuclear fuel reprocessing plants. Combined with the actual process flow and monitoring measures, this paper selects the available parameters as the input. Combined with the process characteristics of nuclear fuel reprocessing and minor corrections, this paper establishes the model for the organic phase fire accident of 1A column based on the empirical formula of organic phase burning rate. In addition, FORTRAN has been chosen to code the software. And the numerical results show that the estimation model can satisfy the quest of nuclear emergency during organic phase fire accident of 1A column in nuclear fuel reprocessing plants.

Key words: nuclear fuel reprocessing, nuclear emergency, 1A column, fire accident, source term estimation