In this study, a small-scale natural gas liquefaction device was built to verify the feasibility of optimization results of the dual nitrogen expansion natural gas liquefaction process with pre-cooling. From the thermodynamics perspective, the feasibility of using R22 instead of propane as a pre-cooling refrigerant, and nitrogen instead of natural gas as the feed gas was verified. Furthermore, a genetic algorithm was used to optimize the operational parameters of the dual nitrogen expansion liquefaction process. The operational performance and adaptability of the process were evaluated based on sensitivity experiments. The experimental results revealed that the relative error of the key node parameters between the experimental and simulation results was within 10%. Moreover, the experimental device and liquefaction process had a relatively large processing capacity (approximately between 35% and 130%), which is suitable when gas field production attenuation is relatively fast. The experimental device was insensitive to the pressure and temperature of the feed gas, and exhibited excellent adaptability.

在这项研究中，建立了一个小型天然气液化装置，以验证采用预冷却的双氮膨胀天然气液化工艺优化结果的可行性。从热力学的角度，验证了使用R22代替丙烷作为预冷制冷剂以及使用氮气代替天然气作为进料气的可行性。此外，遗传算法被用来优化双氮膨胀液化过程的操作参数。基于敏感性实验评估了该过程的操作性能和适应性。实验结果表明，关键节点参数与实验结果之间的相对误差在10％以内。此外，实验装置和液化过程具有相对较大的处理能力（大约在35％和130％之间），适用于气田产量衰减相对较快的情况。该实验装置对进料气体的压力和温度不敏感，并且显示出优异的适应性。