Reza Azin

Flare gas recovery (FGR) is known as an option to reduce greenhouse gases (GHG) from oiland gas refineries. The major concerns about environmental impacts of GHG emission leadrefineries to deploy different FGR methods, most of which requiring new equipment andhigh cost of design and construction. In this paper, feasibility of three methods for FGRis evaluated in a giant gas refinery in Iran. The first two methods considered liquefactionand LPG production by implementing flare gases as feed for existing LPG unit. Differentparameters were studied in feed liquefaction and LPG production. The third studied optionis using a three-stage compression unit to compress the flare gases. Finally, an economicevaluation was performed to find the most profitable method. Based on simulation results,the 0.75-barg pressure of flash drum leads to maximum LPG production. For FGR, the 1-barg pressure of flash drum recovered the most CO2-equivalent from releasing into theatmosphere, which is more than 205 ton/day. The economic evaluation shows that rate ofreturn (ROR) for liquefaction unit and LPG production unit are more than 200% for differentscenarios and are higher than compression.