Shale Gas Processing Integrated with Ethylene Production: Novel Process Designs, Exergy Analysis, and Techno-Economic Analysis

An important impact of shale gas on the chemical industry is the production of value-added chemicals from natural gas liquids (NGLs, C2H6, C3H8, C4H10, C5+). In this paper, three novel process designs are proposed for integrating shale gas processing with ethylene production. The unique feature of the proposed process designs is the coprocessing of shale gas and ethane cracking gas. On the basis of detailed process modeling and simulation, we develop detailed thermo-economic models and exergy analysis for the process designs. The results show that the proposed process designs using NGLs-rich shale gas have an adverse impact on both the overall exergy efficiency and total capital cost when compared with that of conventional shale gas processing design. However, technology integration and better quality of raw shale gas can significantly increase the profitability of the proposed process designs. The estimated net present values (NPVs) of proposed designs are 1.7-2.4 times greater than that of the conventional design. In addition, the NGLs-rich shale gas generally results in 3.17-5.12 times higher NPV than NGLs-lean shale gas.