Effects of Injection Pressure on Emission and Components of Particulate Matter From Marine Diesel Engine

Reduction of particulate matter (PM) is important issues even for shipping industry since PM harms the environment and human health. In order to reduce PM from marine diesel engines, we focused on components forming PM, elemental carbon (EC), organic carbon (OC), sulfate, and “others” (nitrate, bound water associated with sulfate, metal, ash and hydrogen associated with OC), and investigated the reduction effect of each component by changing fuel injection pressure of a four-stroke marine diesel engine at the two engine load points of 25% and 50%. At 50% load, the PM emissions decreased with increasing the fuel injection pressure, the reduction in the PM emissions which reflected the decrease in EC. At 25% load, the PM emissions did not decrease simply with the injection pressure since OC, sulfate, “others” components in addition to EC contributed to the injection pressure dependence of PM. The results suggest that behaviors of each component of PM should be grasped to achieve the appropriate reduction method of PM.