Ash-forming elements in four Scandinavian wood species part 3: Combustion of five spruce samples

A1 Journal article (refereed)

Internal Authors/Editors

Publication Details

List of Authors: Werkelin J, Lindberg D, Bostrom D, Skrifvars BJ, Hupa M
Publication year: 2011
Journal: Biomass and Bioenergy
Journal acronym: BIOMASS BIOENERG
Volume number: 35
Issue number: 1
Start page: 725
End page: 733
Number of pages: 9
ISSN: 0961-9534


Forest residue is the remaining fraction after the outtake of timber, which comprises the tree tops and branches. It may as fuel cause damage to the combustion device through ash slagging and fouling. The objective of this work was to model the ash composition from well-specified samples of a spruce tree: wood, bark, twigs, needles, and shoots. Their ash at 1000 degrees C was modelled using global chemical equilibrium calculations, and laboratory-made ash of the five samples was analyzed by XRD and SEM-EDXA. According to the results, the risk of slagging arises from the spruce foliage: molten alkali silicates from spruce needles and probably molten alkali phosphates from spruce shoots may cause problems in the furnace. Fouling caused by condensing alkali vapours can be produced by all five samples. The amount of alkali vapours in the flue gas was in the same order of magnitude for all five samples, in spite of large differences in their original alkali contents.


Ash, Biomass, Equilibrium, Forest residue, Wood

Last updated on 2020-18-09 at 05:58