diesel selective catalytic reduction
Diesel Selective Catalytic Reduction (SCR) is a top-flight emissions control technology for reducing nitrogen oxides from diesel engines. The main job of SCR is to transform the harmful NOx into inert nitrogen and water vapor, conforming with the strict environmental regulations. Technological features of SCR include a catalyst typically coated with precious metals and the injection, as a liquid-reductant agent (usually urea), into the exhaust stream. This process only happens in a precise temperature range, so as to guarantee maximum conversion efficiency. SCR technology systems have long been employed in a wide variety of applications, such as heavy-duty trucks, buses, and industrial machinery. It represents an important part of the attempt to make diesel engines cleaner and more sustainable.