Search Results

The selective catalytic reduction (SCR) of nitrogen oxides (NOx) is the most promising technique to meet prospective emission regulations of diesel-driven commercial vehicles. Due to the installation of SCR- systems downstream of both the oxidation catalyst and the particulate filter, the relatively long light-off phase after engine startup limits the overall efficiency of reducing emissions. Another challenge is the fact that, once the light-off temperature is achieved it must be maintained. In particular, the operation of urban busses with highly transient load profiles involves many phases of idling with low exhaust gas temperatures (e.g., during bus stops and/or at traffic lights). In contrast to previous studies, these investigations combine properties of catalysts determined in the course of experiments with the simulation of real operational profiles.

The increasingly stringent emission legislation worldwide and the demand for independence from fossil energy carriers represent major challenges for the future development of diesel engines, particularly for maintaining the diesel engine’s positive characteristics, such as its dynamic driving performance and fuel economy, while drastically reducing emissions. This survey investigates alternative fuel blends used in a state-of-the-art EURO 6 diesel engine with different shares of biomass to liquid, hydrotreated vegetable oils and fatty acid methyl ester, which present a possibility to meet these requirements. In particular, the reduction of particulate matter and, as a result, the possibility to reduce nitrogen oxides emissions holds remarkable potential for the application of synthetic fuels in diesel engines. The investigated fuel blends generally demonstrate good applicability when used in the test engine with standard settings.