In the Natural Gas industry, gas/liquid coalescers are used for recovery of lube oil downstream of a compressor. All liquids will be removed but lube oil recovery is the primary reason for installing a coalescer on the outlet of a compressor. Liquids from upstream of the compressor, which may include aerosol particles, entrained liquids or large volumes of liquids called "slugs" and which may be water and/or a combination of hydrocarbon liquids should be removed by a filter/coalescing vessel located upstream of the compressor. Efficiencies of gas/liquid coalescers are typically 0.3 Micron liquid particles, with efficiencies to 99.98%.