A distillation tower for use in a petrochemical or petroleum operation effects liquid and vapor separation by using centrifugal force applied to the feed introduced into a ring from a tangential inlet. The feed is separated into a liquid component that flows into the bottoms section of the tower and a vapor component that flows upwardly through the core of the ring to a wash zone in the tower. De-entrainment devices are provided in the core so that the vapor swirling upwardly impacts the devices and any remaining entrained liquid is separated from the vapor. As a result, overflash with decreased resid can be collected from the wash zone and used as feed suitable for a fluid catalytic cracking operation, for example.