Abstract Number: 1585 Working Group: Aerosol Toxicology
Abstract This study used four different gaseous fuels, including H2, imported nature gas (CH4), Taiwan domestic natural gas (90%CH4, 10%CO2) and biogas (70%CH4, 30%CO2), as control measures on fine particulates and other pollutants emitted from heavy diesel engines. Furthermore, diesel particulate filter (DPF) was also deployed to further reduce fine particulate emissions. The percentages of gaseous fuel to total fuel (gaseous fuel + diesel fuel) were 10% and 20%, respectively. The experiments were conducted using a 6-cylinder, heavy-duty diesel engine in a direct-injection mode (Hino W06E), coupled with a dynamometer (Schenck W230) which was used to control the engine torque and speed. The engine had a 6-liter capacity and was water-cooled and naturally aspirated. The diesel engine tests were carried out with three selected modes out of the 13 European Steady Cycles (ESC) modes: mode 1 (idle, 750 rpm, 0 % load), mode 6 (1650 rpm, 270 Nm) and mode 3 (1950 rpm, 96.2 Nm). The influence of these control measures on the physical and chemical properties of particulates from heavy diesel engines were discussed. The results showed that after adding gaseous fuels, the thermal efficiency only declined slightly compared to using diesel as fuel, but NOx was decreased 5-25%, and the reduction of opacity was even higher than 50%. In general, adding gaseous fuels can also reduce emissions of PM2.5, TPM, and PAHs at 75% load which engine efficiency is greater. Except for CH4 gaseous fuels, adding other gaseous fuel with diesel can reduce PAH emissions, especially for H2, which reduce 88% of PAH mass emissions and 50% of PAH BaPeq emissions. Therefore, adding gaseous fuels can be a candidate technology that can both reduce PM (including PM2.5) and NOx at the same time, which is hard to overcome. Although adding gaseous fuels will increase the emission factors of particulate number from heavy diesel engines, DPF can be deployed to remove 99% of non-volatile particulate matter. The optimization of engine operation and combustion condition for gaseous fuels needs to be further studied to ensure pollutants removal and further increase their removal rates.