Demister Pad / Mesh

A demister pad, also known as mist eliminator or mesh pad, is a structured packing component installed in vapor-liquid separators, scrubbers, distillation columns, and other process equipment. It consists of multiple layers of knitted or woven wire mesh, typically made from corrosion-resistant materials, arranged to create a tortuous path for gas flow. As vapor passes through the mesh, liquid droplets impinge on the wire surfaces, coalesce into larger droplets, and drain away by gravity, resulting in dry vapor output and recovered liquid.

The demister pad operates on inertial impaction, interception, and diffusion principles. When vapor containing entrained liquid droplets flows through the mesh, droplets collide with wire surfaces due to momentum (inertial impaction). Smaller droplets follow gas streamlines but are intercepted by wires when their trajectory brings them within one droplet radius. Droplets coalesce upon contact, forming larger droplets that drain downward by gravity while cleaned vapor continues upward. Mesh density, thickness, and material determine separation efficiency and pressure drop.