화학공학소재연구정보센터
Energy & Fuels, Vol.28, No.11, 6966-6973, 2014
Characteristics of Bio-Oils Produced by an Intermediate Semipilot Scale Pyrolysis Auger Reactor Equipped with Multistage Condensers
The pyrolysis vapor produced from pine wood using an intermediate pyrolysis auger reactor (72 s of solid residence time at 500, 525, and 550 degrees C) was condensed by three different temperature-profiled condensers. The first condenser had a surface temperature of 6085 degrees C and a vapor temperature of 126-193 degrees C, whereas the second condenser had a surface temperature of 40-60 degrees C and a vapor temperature of 107-126 degrees C. The surface temperature of the third water-cooled condenser was <= 25 degrees C, and the vapor temperature was similar to 33-99 degrees C. The water content was very low (11.1-13.9 wt %) in the bio-oil generated by the first condenser; however, it significantly increased in the bio-oil from the second (28.3-39.2 wt %) and third condensers (52.0-64.0 wt %), which led to the bio-oils with lower viscosities and densities. As the pyrolysis temperature increased, the water-insoluble fraction of the bio-oil was the highest (44-47 wt %) in the first condenser and was significantly lower in the second and third condensers (17-27 wt %). The weight-average molecular weight (M-w) was higher (369-423 g/mol) in the first condenser than in the second and third condensers (275-296 g/mol). Most of the levoglucosan condensed in the first condenser. As the pyrolysis temperature increased from 500 to 550 degrees C, the water content and total acid number (TAN) decreased in each condenser, whereas the insoluble fraction and weight-average molecular weight (M-w) increased in each condenser. Acidic compounds mainly condensed in the second condenser by their dew point and density, whereas a large amount of furans, aldehydes, ketones, alcohols, and phenolic compounds condensed in the first condenser.