Study On The Emission Of High-Speed Marine Diesel Engine

With the increasing deterioration of global environment and gradually strengthening consciousness of the environmental protection, the requirement of controlling engine emissions has been heightened. Due to the emissions from marine diesel engine with the characteristics of high fluidity, extensive diffusibility and long duration, the serious jeopardize to the environment has arose high attention of International Maritime Organization (IMO) and governments around the world. Recently, IMO has approved proposed amendments to the MARPOL Annex VI regulations to reduce harmful emissions from ships, also our national departments are pressing on with enacting associated regulations to control emission pollution from marine engine.Firstly, for IMO has adopted amendments to the associated Technical Code on control of emission of nitrogen oxides from marine diesel engines, the thesis introduced the differences between the old and new edition of NOx Technical Code, then studied the distinctions between two editions of NOx calculation methods and their effect on the emission results through the experimental research on high-speed marine diesel engines and contrastive analysis of emission results obtained with different editions and different calculation methods. The results showed that: there is almost no change of the NOx humidity correction factor and it almost has no effect on the emission results. The new edition of dry to wet correction factor is classified according to the complete and incomplete combustion types of engine, and it has some effect on the emission results. The NOx emission result calculated with new carbon balance method is lower than that calculated with old carbon balance method, but it is more similar with the result calculated with air and fuel measurement method, which also demonstrate the superiority of new carbon balance method.Secondly, due to there is no associated emission regulations for inland waterway marine diesel engine in China, the thesis did research on particulate emission testing method on the test bed for marine diesel engine, then analysed the effect of fuel quality on the emissions from marine diesel engine and the correction factor of sulfur content for the particulate emission. Finally, based on the experimental data the correction factor obtained is different from that is given by the U.S. EPA, However, the reason for the difference between them will be further studied.In conclusion, the thesis focused on the study of the emission of marine diesel engine. The results obtained have directive significance to the development of emission testing technique of marine diesel engine and the establishment of the emission regulations in China. Furthermore some flaws and problems will be studied and reported in due course.