石油系重質油を溶媒とする石炭のソルボリシス(VI)

パイプリアクターによる熱処理

抄録

Heat?treatment of coal?asphalt mixtures were performed using a bench scale pipe reactor in order to determine the effect of heating rate on solubilization of coals by solvolysis.Coals tested were a bituminous coal (C: 82.6%) and a brown coal (C: 76.3%), and Khaf ii asphalt (vacuum residue) was used as a solvent for solvolysis reaction of coal.
The asphalt or coal-asphalt mixture (1: 2 by weight) was continuously fed into th pipe reactor, which was heated at a temperature between 450 and 540°C by salt bath fo rapid heating.The inner diameter of the pipe reactor was 3 mm, and initial heating rate o coal slurry was estimated about 2700°C/min.
After the heat-treatment, the yields of pitch, oil and gaseous product were determined (Fig.3), and then the solvent extraction of the pitch, analysis of the oil and gaseous product were carried out.It was shown that the viscosity of pitch was remarkably decreased with increasing in reaction temperature.(Fig.5) Dependence of the conversion of coal to solvent soluble matter on reaction temperature was determined from the result of solvent extraction, and maximum conversions for the bituminous coal and the brown coal were 73.2 and 46.7%, respectively.(Fig.9 and 11) It was found that the conversion of brown coal by the rapid heating using the pipe reactor was higher than that by slow heating using batch-wise reactor in solvolysis, because of the predominant thermal decomposition reaction over the polymerization reaction of coal and asphalt in the pipe reactor.Considerable amounts of ethylene and propylene were formed as gaseous products, and olefin-rich oil was obtained.(Fig.6 and 7) At a temperature above 520°C, however, the formation of benzene insoluble matter from the solvent was observed in the case of brown coal-asphalt mixture.