水熱半炭化スギ燃料の発熱量推定法

抄録

To build a sustainable society, the solid biofuels have come to attract attention as promising alternative fuels to coal in industrial furnace and boilers. We focused on wet torrefaction (WT) treatment to produce solid biofuels with fuel properties comparable to coal. The WT is a thermal treatment in hydrothermal media or hot compressed water in a temperature range of 180-260 ℃. To utilize WT biofuels (WTB) for industrial use, WTB with predetermined energy properties such as higher heating value (HHV) and solid mass yield (YM) has to be produced to meet the requirement in industrial furnaces and boilers. In this study, as the first effort to investigate a generalized estimation of YM and HHV of WTB, WT experiments are conducted by using Japanese cedar. The aim of the study is to clarify the effects of WT conditions (WT temperature, residence time, biomass/water mass ratio) on the energy characteristics (YM and HHV) of the wet torrefied Japanese cedar fuels (WT-Cedar) and the proportion of three major polymers (cellulose, hemicellulose, lignin) contained in the WT-Cedar. Experimental correlations of YM of three major polymers are presented with WT conditions. It is found that the YM and HHV of WT-Cedar can be estimated within an accuracy of about 10%.