Mass exchange network synthesis using exergoeconomic method

Mass exchange network (MEN) is an important part of chemical process. Many methods have already been developed for MEN synthesis to increase the producting efficiency, such as minimizing material consumption, optimizing total annualized cost and so on. However, the energy utilization of MEN has scarcely been studied before. This paper introduces exergoeconomic analysis to MEN synthesis. The integrated analysis of energy and economic factors could provide a better guidance for production operation. The most important merit of exergoeconomic analysis is that the MEN synthesis can be further integrated with the energy exchange networks, such as heat and pressure exchange networks. Therefore, the feasibility of exergoeconomic method used in MEN synthesis is studied. A case study of water network synthesis is carried out to reveal the feasibility of exergoeconomic analysis in optimizing MEN. The optimization turns out to be a mixed integer nonlinear programming (MINLP) problem because of the multi-objective and multiconstraint factors. Genetic algorithm (GA) is employed to get a globally optimal solution based on MATLAB program. The calculation shows that the result of MEN exergoeconomic analysis is basically consistent with that of waste minimization, with a little difference according to the energy and economic factors. Therefore, exergoeconomic analysis is proved to have a good performance in solving mass exchange network synthesis problems.