Ward manufacturing saves energy by recovering heat.

Two years ago, Ward Manufacturing, Blossburg, Pa., installed a new cupola and emission control system as part of its MACT compliance program. The cupola modernization was engineered by Kodiak Group, Grayling, Mich., for Electric Controls and Systems, Birmingham, Ala.

Part of the new system was an Escher dry flue gas cooler supplied by Maumee Valley Fabricators Inc., Toledo, Ohio. This cooler reduces the temperature of the cupola's gas stream to the point where it can enter the dry style baghouse dust collection system supplied by GMD Environmental Technologies Inc., Fort Worth, Texas. This baghouse dust collection system is simple in design and maintenance, making it easier to meet emission requirements of new MACT standards.

Originally the clean side transfer heat was discharged outdoors. Ward Manufacturing decided to install a Kodiak- designed duct system to capture the heat and circulate it back into the plant.

"The new cupola and emission control system allowed the plant to have excess heat just pouring out into the atmosphere," said plant engineer John Hummel. "I had the heat available, why not use it? Especially in this era of increasing energy prices."

Ward Manufacturing's metalcasting facility, which melts 280-300 tons of malleable and gray iron a day, installed its heat recovery system in December 2005. The system is designed to redirect 100,000 cfm of clean, 350F air to existing makeup-air inlet hoods for dilution mixing before entering the existing distribution systems. No additional fans or energy were required. Spill dampers allow the system to be bypassed during warmer months.

"Since the heat recovery system was installed in December, the casting facility has reduced its natural gas consumption by 9-10%," Hummel said. "We have saved, on the average, 5,200 decatherms and $64,000 a month." This savings was in addition to the initial gas savings recognized with the Escher recuperator, which eliminated the gas-fired blast air heater.