Chapter 5: Integrated Multi-Objective Differential Evolution and its Application to Amine Absorption Process for Natural Gas Sweetening

This chapter presents the Integrated Multi-Objective Differential Evolution (IMODE) program, useful for solving Multi-Objective Optimization (MOO) problems. The algorithm in this program has four main parts: multi-objective differential evolution, tabu list for avoiding revisit of search space, self-adaptation of algorithm parameters, and two search termination criteria besides maximum number of generations. All these features of the IMODE make it reliable and efficient for solving engineering optimization problems. As MS Excel is familiar and readily available to practitioners and researchers, the IMODE program is implemented in MS Excel. In natural gas industry, Amine Absorption Process (AAP) is commonly used to remove acid gases from natural gas. To illustrate the application of the IMODE program, this process is simulated in Aspen HYSYS, and then optimized using the IMODE program for two objectives: capital and operating costs. Finally, performance of the two improvement-based termination criteria in the IMODE program is compared using the multi-objective performance metrics.