Title:
Enthalpy for Thermochemical Conversion of Spruce Wood in a Fluidized Bed at Various Temperatures - An Experimental Heat Balance Analysis
Author(s):
Waizmann, G., Schmid, M., Schweitzer, D., Gredinger, A., Beirow, M., Dieter, H., Scheffknecht, G.
Document(s):
Paper
Slide presentation
Abstract:
Within this study the required enthalpy for the thermochemical conversion of spruce wood in steam atmosphere was measured at different temperatures from 319 °C to 570 °C, ranging from torrefaction and pyrolysis up to the onset of gasificationconditions. A heat balance analysis on an electrical heated bubbling fluidized bed reactor was used to measure these enthalpies, where the heat losses of the system were account for by calibration. The measuring principle could be verified by utilization of two well-known calibration substances inherently different in their phase: liquid H2O and solid SiO2. A detailed explanation of the applied measuring procedure is given. The challenges and the origin of uncertainties are explained. The measured enthalpies do not indicate any specific temperature range at which significant large endothermic or exothermic reaction occur. They rather show roughly aconstant rise with temperature. The measured specific conversion enthalpies range from 0.6 to 1.3 MJ/kg on dry basis, which is, compared to the HHV of spruce wood, rather small. And compared with the enthalpy required to get close to the equilibrium composition (i.e. complete conversion) at higher temperatures, this denotes that most of the heat input needs to be supplied at even higher temperatures than analyzed (> 600 °C).
Keywords:
pyrolysis, steam gasification, torrefaction, conversion enthalpy, heat balance, spruce wood, steady state
Topic:
Biomass Conversion Technologies for Heating, Cooling and Electricity
Subtopic:
Gasification for synthesis gas production
Event:
23rd European Biomass Conference and Exhibition
Session:
2DO.5.1
Pages:
646 - 651
ISBN:
978-88-89407-516
Paper DOI:
10.5071/23rdEUBCE2015-2DO.5.1
Price:
FREE
