Quantifying Gas Evolution Rates in Complex Hydrocarbon Systems

While much of gas-liquid separation is considered a mature technology, key challenges remain in designing compact systems – particularly for subsea applications – and heavy oil service. Separator performance is critically important for the safe and reliable operation of downstream equipment. In compact separators or heavy oil service, the rates of gas evolution are particularly important design parameters. Incomplete removal of gas from liquid, or gas carry-under, may result in unexpected pump cavitation, hydrate formation, erosion, and slugging. In petroleum emulsions, gas evolution can actually impact the emulsion morphology, thereby affecting subsequent oil/water separation. Conventional separator design typically only accounts for the entrained gas bubbles in the liquid, in addition to bulk separation. Therefore, the kinetics of solution gas evolution is a critical uncertainty in gas-liquid separator design, especially in systems that contain surfactants, dissolved solids, and other complex species. This presentation provides a discussion about recent gas evolution data collected in hydrocarbon systems with special focus on petroleum emulsions.