Abstract
The quality of marine fuel oil has decreased due to high costs brought about by the exhaustion of fossil fuels and the inflow of investment. On the other hand, the IMO (International Maritime Organization) will introduce strict measures on air pollutants from ships. The emission reduction of PM (Particulate Matter) in particular, is absolutely essential. Therefore, this study focused on coal oil as a next-generation fuel. In our previous study, DS (Dry Soot) and SOF (Soluble Organic Fraction) behavior in the PM was reported. However, the formation characteristics of Cenosphere have not been clarified yet. In the present study, the combustion state and exhaust gas properties of Coal Oil and Coal Oil water-emulsified fuel were investigated. The following results were confirmed (1) Coal Oil has a low reaction rate since it contains aromatics, (2) SOx and NOx concentrations in Coal Oil emissions can be reduced by water-emulsification, (3) Cenosphere in Coal Oil PM is approximately 70-80 % by weight, and (4) exhaust gases from Coal Oil contain carcinogenic substances, e.g., pyrene or benzene series compounds, but these emissions can be reduced by water-emulsification.