The latest and greatest, ideal technology is electrostatic.The other two choices, media and centrifugal have mechanical problems when they interact with a mixture of liquid and solid particles found in machine oil mist and  smoke. Centrifugal and media mist filtration are a huge drain for your company’s money and maintenance resources. Regardless of whether its water, synthetic or oil based, electrostatic mist collection works best.

whatever is being collected.  The mesh must be tight enough to catch submicron particles, much smaller than the eye can see.  This works fine with dry dust because the air can still pass through the accumulation of solid dust particles. Air cannot pass through an accumulation of liquid. Adhesion is what makes the liquid stick to the media filter and solid smoke particles.  Cohesion is what makes the liquid stick together as a droplet or puddle in a blob-like mass.  It is because of these properties that media, no matter how refined the material, will never work beyond an initial particle load to the filter.  The filter becomes wet and does not allow air to easily pass. .

Electrostatic precipitation works great on liquid and solid particles.  It uses 2 stages, the first stage (ionizing) passes contaminated air through a magnetic field that gives all liquid and solid particles an electric charge.  The second stage (collection) moves the air, which is now full of charged mist and smoke particles between metal plates.  These plates have an opposite electrical charge that pulls the particles out of the air stream.  Unlike the woven mesh of media filtration, these plates do not affect the air flow.  Compare the spacing between fibers of the media mesh with the spacing between collection plates.  You can’t even see through the media filters mesh. Collection plates in an electrostatic mist collector can be up to 1/8 of an inch apart!  This gives more than enough space for months worth of microscopic solid particles to build up, while they are saturated with oil or coolant.  The excess liquid, clean of particles, drains off, to be recycled.  And obviously, there are no filters to dispose and replace, just run the cells through your parts washer.  For oil mist collectors, there is no comparison between media filters and electrostatic precipitators.

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