Analysis on the fuel cycle requirements of the FR systems

Maki, Takashi*; Ichikawa, Hajime*; Asao, Takayuki*; Horiuchi, Nobutake*

We developed two computer codes to evaluate fuel cycle requirements of FR systems, which were selected in "the feasibility studies on commercialized FBR cycle systems". One code (CODE for material balance analysis) is to calculate the material balance data to evaluate the characteristics of each candidate. The other is to calculate the time-series data of material balance of fuel cycle as a whole, to evaluate an optimum scenario of FR systems introduction. The main characteristics of these codes are as follows: (1) Common function of both codes (a) They execute burn up calculation using characteristics values of reactor calculated with ORIGEN2 code. And they adjust Pu content using a concept of physical accounting method for adjusted fissile enrichment. (b) They simulate 18 type of FR systems, 10 reactor types and 6 reprocessing types. (2) Function of CODE for material balance analysis (a) It calculates nuclide inventory and thermal power, radioactivity, radio-toxicity in the waste and environmental release. (b) It evaluates safety of geological disposal of HLW and TRU waste (iodine waste) with simplified safety estimation method. (3) Function of CODE for time-series analysis (a) In addition to FR systems, it simulates 4 type of LWR systems and 5 type of Pu-Thermal LWR systems. (b)It calculates the Pu demand-and-supply situation. The precision of these codes was checked and verified by using other code result. Then we investigation characteristics of each FR system by evaluating material balance of fuel cycle. In addition we clarified differences between scenarios of introduction of FR systems.