Steam separator

A steam separator, sometimes referred to as a moisture separator, is a device for separating water droplets from steam. The simplest type of steam separator is the steam dome on a steam locomotive. Stationary boilers and nuclear reactors may have more complex devices which impart a "spin" to the steam so that water droplets are thrown outwards by centrifugal force and collected.

It is important to remove water droplets from steam because:

• In all engines, wet steam reduces the thermal efficiency
• In piston engines, water can accumulate in the cylinders and cause a hydraulic lock which will damage the engine
• In thermal power stations, water droplets in high velocity steam coming from nozzles (or vanes) in a steam turbine can impinge on and erode turbine internals such as turbine blades.

Sources

• Nuclear Encyclopedia article