Search Results

A commercially available exhaust aftertreatment system, DNOX™, comprising exhaust gas recirculation (EGR), an oxidative catalyst and a continuously regenerating diesel particulate filter (DPF) were tested. The test object was a 9-litre ethanol-fueled diesel engine from Scania equipped with turbocharger and aftercooler. A similar diesel engine from Scania, but running on ordinary Swedish diesel fuel, was used as a reference and a reminder of “the state of the art”. The tests involved two different ethanol fuels containing various ignition improvers, Beraid 3540 and rapeseed methyl ester. Test conditions for the engines were those specified in the European Stationary Cycle (ESC). The aftertreatment system reduced the emissions of HC, CO and NOX, down to 0.15, 0.04 and 2.54 g/kWh, respectively, while the estimated particle mass was reduced by 67%. Actually, by using the DNOX™ system, the engines became Euro IV engines regarding the emissions of HC, CO and NOx.

Experiments were performed to investigate the potential to achieve low emissions from a diesel engine fueled by ethanol and equipped with a commercially available exhaust after-treatment device, DNOX™ from STT Emtec. The DNOX™ system includes exhaust gas recirculation (EGR) catalysts and a continuously regenerating diesel particulate filter (DPF). Two Euro III classified 9-liter turbocharged, after-cooled diesel engines from Scania were used for the task. One engine was fueled by ethanol and the other by Swedish diesel fuel, EC1. Engine operating conditions of a 22-mode test cycle, including the 13 modes of the European Stationary Cycle (ESC cycle), were used for the tests. The emissions of NOX and HC were small for the ethanol-fueled engine, 3.48 and 0.53 g/kWh, respectively, while the emission of CO was higher, 2.07 g/kWh. Estimations of emitted particle mass were calculated by using the software supplied in the Scanning Mobility Particle Sizer (SMPS).