A novel NGL/LNG integrated scheme based on C3MR refrigeration system is modeled by using Aspen plus® in this study. The mentioned scheme utilizes mixed refrigerant to provide some of the required cooling in the ethane recovery unit, in addition to producing LNG with the low power consumption. The optimal operating conditions for the proposed configuration are determined by considering the earned profit. For this, a surrogate model is formulated by exploring the design space based on the response surface methodology. The optimal conditions from the mathematical model are obtained using genetic algorithm. The results show that the products sales revenue increases by 88% in the proposed scheme, while 26.65% of this increased revenue is spent on the increased investment and operational costs. Most of these costs belong to the added compressors and cryogenic shell and tube heat exchangers. Moreover, ethane recovery is increased by 25% in the proposed scheme compared to the industrial plant, while the cost of steam consumption is reduced by 11.61%. The exergy analysis shows that the overall efficiency is 53.67% for the proposed configuration and 71.79% of the total exergy destruction occurs in the LNG unit. The compressors of this unit have the highest share in the exergy destruction.

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