An exhaust gas recirculation (EGR) cooler module from Pierburg Inc. is said to cool exhaust gases sufficiently to reduce nitrogen oxides (NOx) by up to 70%.
Pete Hradowy, vice president, sales and engineering, said the cooler modules are equipped with a bypass valve that can operate electrically or pneumatically. The valve redirects exhaust gas flow along an integrated bypass channel until the engine has reached its normal operating temperature, after which the valve is closed, the cooler module is activated, and the temperature of the recirculated gases is reduced.Hradowy said the drop in temperature combined with related oxygen decrease reduces NOx emissions. He added that the EGR cooler module’s die-cast aluminum construction allows the transfer of heat from the redirected exhaust gas to the cooler. The aluminum module can reduce the temperature of the exhaust gas by more than 112 °F. “This kind of heat reduction not only decreases the combustion temperature, but also reduces overall NOx emissions,” he said.