Mist eliminators in distillation columns reduce mechanically entrained liquid reaching the overhead system. Their design must consider vapor load, flooding, reflux rate, product purity, condensation, fouling, and especially pressure drop in vacuum columns.

Steam drum mist eliminators operate under elevated pressure and temperature and must control boiler-water carryover into steam. Steam density, boiling entrainment, drum level, foaming, water chemistry, drainage, and support integrity make the application fundamentally different from an atmospheric scrubber demister.

Wet FGD scrubbers expose mist eliminators to slurry droplets, salts, chlorides, high gas volume, and repeated washing. Open vane or chevron geometry, effective wash coverage, drainage, corrosion resistance, gas distribution, and sustainable pressure drop are key design considerations.

Rectangular and non-circular mist eliminators require evaluation of local gas distribution, corners, structural blockage, modular joints, drainage, upstream elbows, and installation access. Average velocity based on width × height alone can hide severe local overload.

Mist carryover can rise at constant gas flow when higher liquid circulation increases spray entrainment, packed-bed holdup, demister wetness, and drainage demand. Gas velocity alone is therefore insufficient for diagnosing separator overload.