Air Compressor Condensate Information

A compressed air system will produce compressor condensate, which is the moisture that drops out of the compressed air flow as it cools. The condensate drained from the system will contain oil if the compressors have lubrication in the compression chamber. This includes oil- flooded rotary screw compressors and reciprocating compressors with lubricated cylinders.

This oily water mixture causes an environmental concern. There are regulations limiting the amount of lubricants that can be drained into local sewer systems. There are several methods for handling the oily water mixture. However, the producer of the oily water is ultimately responsible for complying with environmental regulations.

Air compressor maintenance, in regard to properly draining the system, depends upon the volume of air compressor condensate accumulated. The volume of condensate in a system will vary with weather conditions, depending upon the temperature of the air and its humidity.

For instance, a 100 HP compressor, taking in 400 cfm, will accumulate just over .5 gallons of condensate per hour when the air temperature is 50°F having 40% humidity. This same compressor, operating when the air temperature is 80°F with 60% humidity, will generate just under 3 gallons of condensate per hour.

Do not underestimate the possible damage caused by the accumulation of condensate within an air compressor. Left to build up, rust and scale will accumulate within the piping system and eventually ruin machinery reliant on the air supply.