Outlet nozzle position, size, and clearance above a mist eliminator can create strong local velocity differences even when average face velocity is acceptable. Side outlets, short plenums, and unequal multiple outlets can cause localized re-entrainment and fouling.

Raw mist eliminator differential pressure cannot be compared directly when gas flow, density, temperature, or liquid loading change. Clean load-specific baselines or normalized DP trends provide a better indicator of fouling, hydraulic flooding, and long-term separator condition.

Gas coolers and aftercoolers can generate substantial water or hydrocarbon condensate even when the upstream gas contains no droplets. Downstream separation should account for peak condensate rate, actual gas density, bulk-liquid removal, mist polishing, piping drainage, and any further cooling after the separator.

Carbon-capture absorbers can emit mechanically entrained amine droplets, much finer aerosol, and vapor. Conventional mesh or vane demisters may control coarse droplets but may not solve aerosol-dominated emissions, especially where fine particulate or acid aerosol provides condensation nuclei.

Differential thermal expansion between vessel shells, frames, supports, and mist eliminator media can create operating-temperature bypass gaps, compression, warping, and drainage problems. Large plastic or mixed-material assemblies should therefore be reviewed across the full temperature range.