My watch list

Vapor-liquid separator

A vapor-liquid separator is a vertical vessel used in several industrial applications to separate a vapor-liquid mixture. Gravity causes the liquid to settle to the bottom of the vessel, where it is withdrawn.^[1]^[2]^[3]^[4] The vapor travels upward at a design velocity which minimizes the entrainment of any liquid droplets in the vapor as it exits the top of the vessel.

Additional recommended knowledge

Recognize and detect the effects of electrostatic charges on your balance

What is the Correct Way to Check Repeatability in Balances?

Daily Sensitivity Test

The feed to a vapor-liquid separator may also be a liquid that is being partially or totally flashed into a vapor and liquid as it enters the separator.

A vapor-liquid separator may also be referred to as a flash drum, knock-out drum, knock-out pot, compressor suction drum or compressor inlet drum.

When used to remove suspended water droplets from streams of air, a vapor-liquid separator is often called a demister.

Where vapor-liquid separators are used

Vapor-liquid separators are very widely used in a great many indusries and applications, such as:

Oil refineries
Natural gas processing plants
Petrochemical and chemical plants
Refrigeration systems
Air conditioning
Compressor systems for air or other gases
Gas pipelines
Steam condensate flash drums

References

^ William D. Baasel (1990). Preliminary Chemical engineering Plant Design, 2nd Edition, Van Nostrand Reinhold. ISBN 0-442-23440-6.
^ David H.F. Liu (1997). Environmental Engineers' Handbook, 2nd Edition, CRC Press. ISBN 0-8493-9971-8.
^ Stanley S. Grossel (June 2004). "Design and sizing of knock-out drums/catchtanks for emergency relief systems". Plant/Operations Progress (AIChE) 5 (3): 129-135. ISSN 0278-4513.
^ Stanley M. Walas (1988). Chemical Process Equipment:Selection and Design. Butterworth- Heinemann. ISBN 0-409-90131-8.