Abstract:

As one of the branches of process integration, the synthesis of mass exchange network (MEN) has attracted more and more attention in the area of process systems engineering.When synthesizing a MEN, the composition differences (ε) reflect the impetus of mass transfer between rich and lean streams and affect the operating cost and capital cost significantly, so they should be optimized in order to obtain a real optimal MEN.However, so far they are usually given arbitrary values in most literatures, which cannot guarantee an optimum MEN obviously.This paper presents a simultaneous method to solve the problem of ε in a single-contaminant or multi-contaminants system, which builds the superstructure model of the MEN first, takes total annualized cost (TAC) as an objective and considers εas a set of variables to balance operating cost and capital cost.Then the mathematical model is solved by means of an improved genetic algorithm.Finally, the minimum TAC and corresponding ε values, as well as an optimal MEN are also obtained simultaneously.