Techno-economic evaluation of flare gas recovery configurations using gas turbine generator (GTG), steam turbine generator (STG), and organic Rankine cycle (ORC) for power and byproduct recovery

Abstract This study evaluates three flare gas recovery (FGR) configurations for simultaneous steam and power generation, using combinations of gas turbine generator (GTG), steam turbine generator (STG), and organic Rankine cycle (ORC). Process simulations and performance evaluations were performed in Aspen HYSYS, and the economic analysis was carried out in Aspen Process Economic Analyzer. The results indicate the following electricity generation for each configuration: GTG + STG: 2.50 MW (highest efficiency), GTG + STG + ORC: 1.64 MW [additional recovery of Liquefied Petroleum Gas (LPG) and C5+ products at lower efficiency], and GTG: 0.93 MW. Estimated total capital investments for the three cases are approximately: GTG + STG: 19.1 million USD, GTG + STG + ORC: 26.0 million USD, and GTG: 16.0 million USD. Overall, the findings highlight the trade-offs among power-generation efficiency, byproduct recovery, and capital costs when selecting an appropriate FGR configuration. These insights are crucial for decision-makers seeking to optimize energy recovery while balancing economic viability and environmental impact.