In this paper a superstructure optimization is applied for the problem of olefin separation system which includes distillation column units, heat exchangers and heat integration. A new algorithm is presented for modeling the separation system and designing the heat integration and heat exchanger networks. The objective is to minimize the total annual cost of the separation superstructure using the presented design methodology and numerical methods such as improved harmony search algorithm. The developed code is validated and verified using standard cases in literature. The solution approach for the superstructure optimization is discussed and the numerical results are presented proving the improvements in the design of the separation superstructure system using the new presented approach. (C) 2016 Elsevier Ltd. All rights reserved.