Inventory estimation method study for evaporation concentrator

Nuclear Material Control Center has been studying inventory estimation method for an evaporation concentrator installed in large scale reprocessing plant. Solution volume and nuclear material concentration are required to estimate the inventory. Since the evaporation concentrator will be operated continuously, drawing solution out of the evaporation concentrator is impossible. Therefore we made out two equations to estimate solution volume and nuclear material concentration using instrumental signals (e.g. level, density, temperature). One correlates solution volume to the flow rate of feed solution and heating steam. The other correlates solution concentration to density and temperature. It was recognized that reproducibility of each equations are less than 0.5% and 1.5%. (author)