Analyses of Pellets Produced from Spruce Sawdust, Spruce Bark, and Pine Cones in Different Proportions

Abstract

A lot of residual biomass has energy value and can be used for further applications through suitable treatments, such as pelletization. This treatment can improve properties, mainly energy density, but can also lead to problems due to their low ash melting temperatures, high ash content, and the formation of harmful compounds during combustion. This article deals with the energy potential of pellets produced from spruce sawdust, spruce bark, and pine cones in different proportions. The impact of cone and bark contents on pellet properties was also observed. The energy properties of the produced pellets were measured, such as the contents of carbon, hydrogen, nitrogen, moisture, volatile, fixed carbon, and ash, as well as calorific values and ash melting temperatures. Based on the results, it can be concluded that the addition of pine cones and spruce bark to spruce sawdust mainly affected the contents of nitrogen and ash and melting temperatures. Despite this, all produced pellets met the standard EN ISO 17225-2 for the content of nitrogen, ash, and also lower calorific value at least B quality. However, only three pellet samples of five met this standard for A2 and B quality for ash melting behavior. Therefore, they present an alternative fuel with interesting energy potential.