Acta Scientiarum Polonorum
Silvarum Colendarum Ratio et Industria Lignaria

The paper presents research results into quantities of branches and tree tops forming logging residues as well as the calorific value, moisture and ash contents of chips burned in a fluidal boiler. The results showed that logging residues make up 17% of the above ground tree biomass, which gives about 52.8 t/ha. The calorific value of the wood chips was 7.8 MJ/kg for fresh material, 12.9 MJ/kg for chips after 4 month storage time and 16.2 MJ/kg after storing the chips for 8 months. The ash from chips burned in a boiler with a fluidised bed contained 62% of silicon dioxide, resulting from the filling role of sand in the fluidal bed. The share of CaO was 6%, MgO – 2.8% and N2O – 0.4%.