100 samples of recycle solvent were obtained from continuous opera-tion (50 days) of 1 ton/day coal liquefaction plant at Kimitsu. Phenanthrene and anthracene derivatives in the recycle solvents were analyzed in detail by the technique of selective ion measurement GC/MS. According to the replacement of the initial solvent by coal-derived products, the amounts of phenanthrene derivatives decreased remark-ably, while those of anthracene derivatives decreased slightly. For phenanthrene deriv-atives, octahydrophenanthrenes play an important role as hydrogen donors by releasing eight hydrogen atoms in the recycle solvent, on the other hand for anthracene deriva-tives, tetrahydroanthracene plays an important role by releasing four hydrogen atoms. This results indicate that hydrogen donatable ability of phenanthrene derivatives is twice as large as the ability of anthracene derivatives.
Mixing solid particles has been recognized as a effective means of getting highly promoting combustion ability of hydrocarbons, which has been attempted to be used for aviation and space vehicle engines. In this study, ignition and combus-tion characteristics of a solid paritcle mixed fuel drop have been measured under normal gravity and microgravity conditions in order to get a fundamental understanding on com-bustion processes of a solid particle mixed fuel spray. The experiments were conducted in a drop tower, which has a fall of 710 m and a duration of 10 seconds of the microgravi-ty condition. A mixture of magnesium or pure carbon powder and n-Dodecane or n-Hexadecane were used for solid particle mixed fuel which has a 40‰ mixing ratio. Comparison of the experimental results between under the microgravity condition and under the normal gravity condition clarifies differences in combustion characteristics between the two. The minimum ignition temperature of the fuel droplet under micro-gravity was lower than that of under normal gravity, and the flame expansion ratio of the carbon slurry under microgravity in high ambient temperatures more than 1000K was larger than that in lower ambient temperatures.
Combustion characteristics of the balsa chips were experimentally studied as the fundamental investigation of the thermal recycle system of the urban dust. The urban dust contains plastics, vegetables and lot of wood materials. Then, a balsa wood was chosen as an example of the one of the components of urban dust. A small balsa chip was burned in an electric furnace and mass reduction rate during volatile and char combustion states were recorded by the micro-electric balance. Ignition delay and the period of volatile combustion was greatly affected by the mass of the balsa chips and ambient temperature in the furnace. When the mass of the balsa chips was larger than 0.5 g, the combustion similarity was found on the normalized mass reduction rate.