A mass and energy balance for a specific refuelling of Angra 2 nuclear power plant from a life cycle perspective

This work presents a detailed analytical balance of the material and energy flows associated with the nuclear fuel dynamics of the Angra 2 nuclear power plant (Brazil). A model is proposed for tabulation of material and energy flows, applied to each life stage of the nuclear fuel cycle, from extraction of raw material and production of nuclear fuel to post-use of fuel assemblies (FAs), when these are transformed into nuclear tailings. The tabulated and systematized data refer to the plant operation over a full load period. Approximately one year is the period of the plant operation after a regular refuelling and, at this period, all the materials and energy inputs are considered in addition to the wastes generated by the nuclear fuel cycle, including the ones due to operation and maintenance of the power plant in that period. Since 1/3 of the FAs of the core are replaced by fresh FAs, this analysis considers energy and material flows related to the production of fresh FAs. Related to these processes, it is taken into account what follows: 1) Uranium mining and processing, 2) Conversion of uranium concentrate into uranium hexafluoride (UF6), 3) Uranium (UF6) enrichment, 4) reconversion of the enriched UF6 to uranium dioxide (UO2), 5) Production of nuclear fuel - from the pellets to FAs, 6) Power generation from plant operation, and 7) Generation and management of nuclear tailings arising from the regular operation of the plant in that period. The analysis of systematized data from the various stages of the cycle allows a broader analysis and the perception of critical aspects, such as the need for technological improvements, logistical advances, care for the environment and public health, increased energy efficiency, in addition to the need for materials recycling, among other possibilities.