Computer-aided simulation procedure for water distillation columns

Abstract

A computer-aided simulation procedure is proposed for a water distillation column which has hundreds of stages. The procedure allows us to simulate a column processing all the six molecular species H2O, HDO, HTO, D20, DTO and T2O. By using the approximation that the isotopic exchange reactions are equilibrated in liquid phase and linearizing the atom balances for two of the three elements (H, D and T) around each stage, the Newton-Raphson iteration is applied to the main calculational loop. As a consequence, the Jacobian matrix has a block tridiagonal form and the order of the arrays is just two even in cases of the six component system. Thus, the serious problem of huge computer storage requirements inherent in previously reported procedures using the Newton-Raphson method is completely eliminated in the present procedure. The procedure is very useful to the solution of operating problems for water distillation columns used as the upgrader of heavy water from the heavy water reactor and the finisher in the heavy water production process. © 1984 Taylor & Francis Group, LLC.