Power generation as a useful option for flare gas recovery: Enviro-economic evaluation of different scenarios

Abstract

Flaring of associated gas from oil wells and excess gas from gas processing units and oil refineries is one of the most critical resources of greenhouse gas emissions to the atmosphere. In addition to environmental impacts, burning flare gases having high heating value results in considerable economic losses. Considering the significant amount of gas flaring in Iran, much more attention should be given to flare gas recovery processes. In the current study, four power generation scenarios, including Gas Turbine Cycle, Combined Gas Turbine Cycle, Reciprocating Internal Combustion Engine Cycle, and Solid Oxide Fuel Cell/Gas Turbine Cycle are investigated in terms of economic and environmental performance, for flare gas recovery purposes. The performance evaluation of the mentioned scenarios was carried out using eight different flare gas samples from different resources in Iran, including four associated gas samples, two samples from the gas refinery, and two samples from the oil refinery plants. The results indicate that among the studied scenarios, RICE and SOFC/GT cycles have the best and worst economic performance, respectively. Samples having higher flowrates showed better economic performance compared to the others. In addition to flowrate, gas composition, i.e., the amount of H2S and H2 existing in flare gas could be determinative factors in the economic profitability of the scenarios. In terms of emission of the pollutants to the atmosphere, RICE showed the best performance among the evaluated scenarios.