Evaporation of Biomass Fast Pyrolysis Oil: Evaluation of Char Formation

摘要

Evaporation experiments of biomass fast pyrolysis oil and its aqueous fractions at low (TGA-10° C/min, Glass tube-100° C/min) and high (atomization ~10~(60) C/min) heating rates are performed. Slow heating of pyrolysis oil produced ~28% char (on carbon basis), whereas atomization of oil droplets (~117 μ m) produced ~9% char in the temperature range of 500-850° C Aqueous fractions and glucose solutions also produced less amount of char by evaporating at higher heating rates (~3% char) when compared with slower heating (~24% char). The results obtained show that not a single lumped components class in pyrolysis oil can be identified that is primarily responsible for the char formation. At low heating rate, higher concentrations of organics in the bioli-quids result in higher char yields, which reveals that a certain fraction in the oil produce char with a reaction order higher than one (polymerization reactions). The measured trends in char yield can be described by a model in which certain fraction of oil is converted by two parallel reactions to char and gas/vapor.