In vacuum systems, even modest mist eliminator pressure drop can raise upstream operating pressure and affect boiling temperature, vacuum capacity, energy demand, and throughput. Actual vapor volume, wet pressure drop, drainage, and fouling margin are therefore critical design inputs.

Sticky, oily, or viscous mist can remain on wire surfaces, increase liquid holdup, trap particles, and rapidly plug dense mesh. Separator selection should consider viscosity, temperature, fouling, cleanability, and long-term operating stability.

Debottlenecking can overload an existing mist eliminator through higher actual gas velocity, increased liquid loading, stronger upstream entrainment, and reduced fouling margin. Existing separator dimensions should not automatically be assumed suitable for the new plant capacity.

Upstream gas cooling can condense vapor into new droplets before the mist eliminator, increasing liquid loading and potentially creating a finer mist than ordinary spray entrainment. Temperature profile and saturation conditions should therefore be part of difficult carryover investigations.

High operating pressure increases gas density and changes mist eliminator pressure drop, droplet behavior, and re-entrainment limits. A velocity acceptable at atmospheric conditions should not be applied directly to pressurized service without recalculating the hydraulic basis.