海水に曝される鋼材に対するオゾンの防食効果

抄録

Thermogravimetric analyses of fuel oil, lubricant and soluble organic fraction (SOF) extracted from particulate matters (PM) of a medium speed 4-stroke marine diesel engine were carried out. The engine was operated with low sulfur heavy fuel oil of about 0.06% by mass sulfur which conforms to JIS K 2205 A-category (LSA). Derivatives of mass fraction with respect to temperatures (DTG curve) of the LSA evaporated to about 10% of its mass at 180 degrees C and that of the SOF sample have peaks at almost the same temperature (about 210 degrees C). With the pre-evaporation process at 180 degrees C, the DTG curve of LSA and lubricant mixture of which the mass ratio of the former to the latter is 2:3 also fits well for that of the SOF sample. Results of the analyses show that the SOF sample originates from the constituent parts of fuel oil of higher boiling point and the lubricant.