Nurmi, J. 1997.
Heating values of mature trees
Acta Forestalia Fennica 256. 28 p.
[ Acta Forestalia Fennica
- The effective heating values of the above and below ground
biomass components of mature Scots pine (Pinus sylvestris),
Norway spruce (Picea abies), downy birch (Betula pubescens),
silver birch (Betula pendula), grey alder (Alnus incana),
black alder (Alnus glutinosa) and trembling aspen (Populus
tremula) were studied. Each sample tree was divided into
wood, bark and foliage components. Bomb calorimetry was used
to determine the calorimetric heating values.
- The species is a significant factor in the heating value
of individual tree components. The heating value of the wood
proper is highest in conifers. Broad-leaved species have a higher
heating value of bark than conifers. The species factor diminishes
when the weighted heating value of crown, whole stems or stump-root-system
are considered. The crown material has a higher heating value
per unit weight in comparison with fuelwood from small-sized
stems or wholetrees. The additional advantages of coniferous
crown material are that it is a non-industrial biomass resource
and is readily available. The variability of both the chemical
composition and the heating value is small in any given tree
component of any species. However, lignin, carbohydrate and extractive
content were found to vary from one part of the tree to another
and to correlate with the heating value.
biomass, heating value, logging residue, lignin, carbohydrates,
extractives, hydrogen, carbon
- Author's address
Finnish Forest Research Institute, Kannus Research Station, P.O.
Box 44, FIN-69101 Kannus, Finland. Fax +358 6 871 164, E-mail
- ISBN 51-40-1561-4