مجله علوم و فنون هستهای (May 2016)
Modeling and Optimization of Operating Conditions of Condensers in UF6 Separation Unit
Abstract
In this study, modeling and optimization of two in-series UF6 shell and tubes separator condensers were performed to improve the prediction of the amount of the mist output, physical properties of condensing gases and condensed mass of UF6 by computing the mist formation conditions. The main objective of this research was to predict the optimal operating conditions in order to reduce the uranium in the outlet mist from the condenser system. These two shell and tube condensers were modeled via control volumes with finite length in axial direction of input gases. The equations of mass, energy and momentum balance were written for each condenser and then surface temperature of UF6 condensed layer on the condenser tube was determined by the trial and error method. The mass and heat transfer parameters were calculated at each time step during the process. Comparison of the modeling predictions with the Isfahan UCF industrial data in regard to important variables indicated a very good compatibility. The average error between the modeling and industrial data for the first and second condensers were calculated to be 1.39 and 2.24%, respectively. Finally, the analysis of the effective variables via the developed modeling computer software revealed that the optimal temperature of cooling brine water and the input gas velocity are 10 ˚C and 0.09 m/s, respectively.
