Valve problem plagues milk processor

A milk processing and packaging facility had two independent compressed air systems running inefficient modulating style compressors to produce the air needed to keep the compressed air powered machines running smoothly. With the help of their power utility they were able to consolidate their two systems into one using a new variable speed drive compressor. This improvement saved 625,000 kWh resulting in a 62 percent reduction in operating costs worth $62,500 per year in savings.

As part of the verification of the savings a compressed air auditor placed data loggers on the system to monitor pressure and power. When the auditor removed his loggers he noticed a significant amount of water at a pressure point downstream of the air dryer. Since the facility produces food product this air quality issue was of high concern. All signs pointed to a problem with the new air dryer.

After some investigation it was found that the dryer was working correctly but the compressor did not have a water separator inside the unit (some manufacturers do not provide) and there was no wet receiver or external separator installed to collect the water the compressor produced. This was corrected but the moisture problem did not go away. Further investigation found that a single three way valve had been installed on the air dryer to provide both a normal and bypass function with only one valve. Careful testing was done with a dew point meter and found that, while the air dryer was working fine, this valve had an internal leak caused by damage to the internal seals. It was allowing moist air to bypass the air dryer.

The valve was removed and a standard 3 valve bypass arrangement was installed, which fixed the problem.

Learn more about air dryer and measurements in our next Compressed Air Challenge seminar in your area. Visit www.compressedairchallenge.org/calendar for more information.