A large industrial plant fell on hard times and had to reduce their production shifts to only 8 hours per day, 5 days per week. The compressed air system remained running full time 24 hours a day, including weekends, due to the need to supply the plant’s dry fire system with air pressure.
The total plant leakage consumed about 500 cfm of compressed air — worth about $60,000 during the 6,000 hours of non-production time — even though there was nobody working in the plant. Flow testing of the fire system showed the fire system consumed less than 1 cfm.
Recognizing the high weekend flow, the plant supervisor installed a small compressor to provide backup for the fire system. During working hours, the main plant compressed air system provides the flow. During shutdown hours a small compressor provides the required compressed air, protected by a check valve, and the main system was turned off — saving substantial energy costs.
The supervisor also recognized that this 500 cfm of air leakage was consuming about 50% of his total compressed air demand, so he commissioned a leakage study. About 75% reduction in leakage was achieved with an aggressive repair program. Resulting savings paid for a new ultrasonic leak detector for the plant — this is used four times per year to ensure the leakage savings are sustained!