Steam Water Separator, ASME SA516-70, 20MWe, 2286mm, Two Phase

A Steam Separator, also referred to as a moisture separator sometimes, is a device for separating water droplets from steam. Wet steam is a major concern in a steam system since it can cause process and maintenance problems, such as erosion, corrosion and lower productivity. 
A Baffle Type Separator (also called vane type separator) consists of a number of baffle plates, which may cause the flow to change direction a number of times when it passes through the separator body. The suspended water droplets own a greater mass and a greater inertia than the steam; therefore, when there is a change in flow direction, the dry steam flows around the baffles and the water droplets collect on the baffles. Moreover, as the separator owns a large cross-sectional area, there is a resulting reduction in the speed of fluids. This reduces the kinetic energy of the water droplets, and most of them will fall out of suspension. The condensate collects in the bottom of the separator, where it is drained away through a steam trap.