Reduction of Hydrocarbon Losses to Flare Systems

Abstract

In the past, refineries and petrochemical plants have emphasized the need to prevent and minimize major hydrocarbon releases to the flare. Although these are given a great deal of attention, the normal daily hydrocarbon losses to the flare seldom merit consideration because the losses and associated economic penalties are assumed to be small. Flare gas flow is not easily measured and as a result, most plants are unaware of how much product they are actually losing during normal operation. This report will discuss a tracer technique used to accurately measure flare losses. Plants can use several methods to reduce hydrocarbon losses during normal operation. The following three are primarily used: 1) monitor the flare system and take corrective action to minimize hydrocarbon releases, 2) install flare gas recovery systems, and 3) recover or reduce process streams which have to be continuous1y vented to the flare system. This report discusses alternate designs for flare gas monitoring and flare gas recovery systems and also presents several case studies.