A compact solid SCR system for NOx reduction in passenger cars and light duty trucks

Abstract

Apart from the NOx adsorber catalyst, which has already been introduced in series for direct injection spark ignition engines, SCR technology represents an interesting solution for reducing NOx emissions from diesel vehicles. However, this requires a reductant such as urea as an additional operating medium. From today’s point of view, a wide-scale provision of the frequently discussed aqueous urea solution does not appear feasible in the short term. Therefore, the use of a solid reductant such as ammonium carbamate, with its considerably lower space requirements, presents an interesting alternative for individual motor vehicles. This article describes the solid SCR system developed by FEV Motorentechnik GmbH, as well as the first vehicle tests.