Title:
Release of Aerosol Forming Elements from Updraft Gasifiers Operated with Waste Wood
Author(s):
Supancic, K., Schlögl, C., Brunner, T., Obernberger, I.
Document(s):
Paper
Abstract:
Waste wood is a rather cheap and CO2 neutral energy source but features a higher ash content and higher contents of sodium (Na), chlorine (Cl), sulphur (S) and heavy metals (especially zinc (Zn) and lead (Pb)) compared to virgin wood. Increased ash contents lead to higher emissions of coarse fly ash particles from the fuel bed. Na, potassium (K) and the heavy metals Pb and Zn are the main aerosol-forming elements in wood-based fuels. Elevated contents of these elements in the feedstock lead to higher aerosol emissions. In addition, increased Cl contents in the fuel can enhance the Na and K release from the fuel bed. Increased coarse fly ash and aerosol emissions cause increased deposit formation in the boiler that decreases the boiler efficiency and shortens the time span between maintenance shutdowns. Fixed bed updraft gasifiers show for virgin wood close to zero coarse fly ash emissions and very low release rates for K and Na. Therefore, fixed bed updraft gasifiers are an interesting option to minimise the adverse effects of waste wood on boiler deposit formation and corrosion in waste wood to energy plants but a detailed investigation of the release behaviour of aerosol forming elements, especially of Zn and Pb is needed. In this respect also the contribution of contaminants in the waste wood such as metals, glass and organic material (plastic, fabrics, etc.) to the release of aerosol forming elements needs to be addressed.
Keywords:
gasification, waste wood, aerosol
Topic:
Biomass Conversion for Bioenergy
Subtopic:
Gasification for power, CHP and polygeneration
Event:
30th European Biomass Conference and Exhibition
Session:
4AO.5.1
Pages:
557 - 566
ISBN:
978-88-89407-22-6
Paper DOI:
10.5071/30thEUBCE2022-4AO.5.1
Price:
FREE
