Efficiently design and operate vertical gas/liquid separators

P. Diwakar and J. Valappil, Bechtel Oil, Gas and Chemicals Inc., Houston, Texas Gas/liquid separators, or knockout drums, are used to eliminate liquid droplets from incoming multiphase flows and prevent liquid carryover to downstream compressors and rotating equipment. Liquid in any quantity is a safety concern, since droplets may cause erosion damage in blades and corrosion in other downstream equipment, especially in the presence of water. The mechanisms governing the separation of liquids and solids from gas include gravity, inertia, shear and turbulence. Most separators use a combination of these mechanisms. The most important principles in a liquid-gas separator are to ensure that: