An aftertreatment system comprises a first passageway having a first temperature and a second passageway having a second temperature different than the first temperature. A turbine is disposed downstream from the first passageway and upstream from the second passageway. The turbine is in fluidic communication with the first passageway and the second passageway. The turbine is structured to receive an exhaust gas from the first passageway, generate energy using the exhaust gas flowing through the turbine and communicate the exhaust gas to the second passageway. The aftertreatment system also includes an insertion device structured to insert an exhaust reductant into the first passageway. A selective catalytic reduction system is configured to receive the exhaust gas from the second passageway and treat the exhaust gas. The first temperature can be higher than the second temperature.