A Close Analysis of Developments in Diesel Engine Emission Reduction Technologies

Diesel engines have the potential to significantly increase vehicle fuel economy and decrease CO 2 emissions; however, efficient removal of NO x and particulate matter from the engine exhaust is required to meet stringent emission standards. Diesel aftertreatment systems being used consists of a Diesel Oxidation Catalyst (DOC), a urea-based Selective Catalyst Reduction (SCR) catalyst and a diesel particulate filter (DPF), and is widely used to meet the most recent NO x (nitrogen oxides comprising NO and NO 2 ) and particulate matter (PM) emission standards for medium and heavy-duty sport utility and truck vehicles. The most efficient way and the best available technology (BAT) to radically reduce the critical Diesel emission components particles (PM&NP) and nitric oxides (NO x ) are combined exhaust gas aftertreatment systems (DPF+SCR). SCR (selective catalytic reduction) is regarded as the most efficient deNO x -system, diesel particle filters are most efficient for soot abatement. Today, several suppliers offer combined systems for retrofitting of HD vehicles.