Considerations for Flare Gas Recovery Unit Design and Operations in An Olefins Plant

In 2011 Flint Hills Resources installed a flare gas recovery unit at its Port Arthur Olefins plant.  This paper will discuss items that had to be considered to apply flare gas recovery in an olefins plant.   The items discussed will include:  how to get accurate flare flow and composition data to size the unit,  how to manage intermittent flare streams with high volume and high nitrogen content,  controls for compressor staging and de-staging,  handling of hydrocarbon liquids  that condense during compression, and lessons learned during startup and operation.