مقایسه رفتار ترمودینامیکی اتان و اتیلن در چرخه مبرد آمیخته فرآیند مایع‏ سازی گاز طبیعی

The type of mixed refrigerant components is one of the most important factors affecting the energy consumption of compressors in the natural gas liquefaction process. In the recent researches, various components have been used, which usually contain ethane or ethylene. So far, no comparison has been performed between the performance of these two components in the mixed refrigerant. In this research thermodynamic properties of ethane and ethylene were compared. Then PRICO process, as the most common small-scale liquefaction process, was simulated with three types of five-component refrigerants including ethane, and then optimized using the genetic algorithm tool in MATLAB 2019a. Then, the thermodynamic effect of ethylene replacement in these three refrigerants on the work consumption of compressors as an objective function was investigated. The results indicated ethane or ethylene presence in mixed refrigerant is necessary and their absence leads to work consumption of 3792.35 kW. This value is higher than all six case that contain ethane or ethylene. Also, results showed that the use of ethylene reduces the work consumption of compressors, and in refrigerants with nitrogen, methane, ethane, propane, and i-butane components, replacing ethane with ethylene reduces process work consumption by 11.28%.