SYSTEM AND METHOD FOR EXHAUST GAS AFTERTREATMENT

In one embodiment, a method for controlling nitrogen oxides in an exhaust gas received by an exhaust system, the exhaust system including a first selective catalytic reduction device, an exhaust gas heat recovery device and a second selective catalytic reduction device is provided. The method includes flowing the exhaust gas from an internal combustion engine into the first selective catalytic reduction device, receiving the exhaust gas from the first selective catalytic reduction device into the exhaust gas heat recovery device and directing the exhaust gas to a heat exchanger in the exhaust gas heat recovery device based on a temperature of the internal combustion engine proximate moving engine components. The method includes adsorbing nitrogen oxides from the exhaust gas via a nitrogen oxide adsorbing catalyst disposed in the heat exchanger and flowing the exhaust gas from the exhaust gas heat recovery device into the second selective catalytic reduction device.