A coalescing filter removes the fine oil and water aerosols that a separator cannot catch. These microscopic droplets would otherwise travel downstream, contaminating products, clogging dryers and degrading tools, so coalescing filtration is a core stage in any serious air treatment system.
How it works
Air passes through a fine fibre media that traps tiny droplets. The droplets merge, or coalesce, into larger drops that drain away under gravity. A good filter removes most oil aerosol and particles down to a fraction of a micron, protecting the adsorption dryer and the point of use.
Where filters belong
- General particulate filter before the dryer
- Coalescing filter before the desiccant dryer to protect the bed
- Final coalescing and dust filter at the point of use
- Activated-carbon filter where oil vapour must be eliminated
Sizing and maintenance
Size the filter for the actual flow and pressure so pressure drop stays low. Change elements on a schedule or when differential pressure rises, because a clogged element wastes energy and can starve the process of air.