The optimal design of single mixed refrigerant (SMR) natural gas liquefaction process is decisive for upgrading the liquefied natural gas (LNG) value chain and can be achieved using process simulators and derivative-free optimization techniques in simulation–optimization frameworks. The process work consumption can be reduced by modifying process flowsheet and manipulating refrigeration cycle thermodynamic conditions and refrigerant composition. The goal of this paper is the design of energy-efficient SMR liquefaction process for LNG production using simulation–optimization approach, in Aspen HYSYS^® and MATLAB^®, that considers more decision variables to be optimized with a Nelder–Mead simplex algorithm and small flowsheet modifications, such as hydraulic turbines and flash separators in between compression stages. The present approach resulted in liquefaction process with network duty of 750.2 kJ per kg of natural gas, which is considerably smaller than those reported in the literature.

单一混合制冷剂（SMR）天然气液化过程的优化设计对于升级液化天然气（LNG）价值链具有决定性，可以在模拟优化框架中使用过程模拟器和无导数优化技术来实现。通过修改工艺流程图并控制制冷循环的热力学条件和制冷剂成分，可以减少工艺工作量。本文的目标是LNG生产节能型SMR液化过程中使用模拟优化方法的设计，在阿斯HYSYS ^®和MATLAB ^®，它认为可以使用Nelder-Mead单纯形算法和较小的流程修改来优化更多决策变量，例如压缩阶段之间的水轮机和闪蒸分离器。本方法导致液化过程，其网络负荷为每公斤天然气750.2 kJ，这比文献中报道的要小得多。