Design and Optimization of a Novel Mixed Refrigerant Cycle Integrated with NGL Recovery Process for Small-Scale LNG Plant

In this study, a novel mixed refrigerant cycle (MRC) integrated with NGL recovery process for small-scale LNG plant is proposed and optimized. The proposed process can be used to produce LNG and NGL with low energy consumption. Genetic algorithm is chosen as the optimization method for the proposed MRC-NGL process. The unit energy consumption as an objective function is optimized with key parameters. The optimization results show that the unit energy consumption and the molar flow rate of the mixed refrigerants can be reduced by 9.64% and 11.68%, respectively, compared with that of the base case. The effects of several key parameters on the process performance are also investigated and discussed based on the optimization results. Furthermore, the exergy analyses of the main equipment are also presented and analyzed. The economic analysis also shows that the proposed process has a good profitability and a short payback period.