Alternative ordering of process hierarchy for more efficient and cost-effective valorization of shale resources

In the past 2 decades, natural gas flaring and venting have increased due to the lack of transforming or transportation infrastructure in emerging shale-gas-producing regions. To reduce carbon emissions and wastage of shale resources, here, we report an alternative process hierarchy for natural gas liquid (NGL) to liquid fuel processes, which enables efficient valorization of shale resources on a small scale near the wellhead. While the conventional shale gas process follows a front-end separation, NGL activation, NGL upgrading hierarchy, our process introduces a hierarchy of NGL activation, NGL upgrading, back-end separation. This proposed hierarchy intensifies and simplifies the entire process by eliminating repeated or unnecessary unit operations and associated equipment. We illustrate the benefit of the proposed process hierarchy through synthesis, simulation, and analysis of an exemplary process via dehydrogenation followed by oligomerization. For small-scale plants, detailed simulation and economic analysis demonstrate this process to be economically attractive.