| Abstract [eng] |
Additives play a major role in wood pellet characteristics and are a subject of major interest as they act as binding agents for the biomass raw material. However, there is a still lack of research and data on the use of additives in the manufacturing of new wood pellets, which have more unequal composition. The purpose of this study was to summarize the current state of the literature and investigate the dependence related to the effects of additives on wood pellet physical and thermal characteristics. The physical characteristics reviewed in this study include moisture content, particle density and mechanical durability, bulk density. Whereas the thermal characteristics reviewed include heating value, ash content, ash melting point, elemental composition. The additives also act as a lubricant and increase the production rate and decrease the energy consumption per unit output of wood pellets. Results showed that lignosulphonate, potato starch, dolomite and motor oil used as adhesive binding agents increased the quality of pellets and changed inorganic characteristics, but did not have a significant effect on their calorimetric heat values. The results have also shown that lignosulphonate improved the mechanical durability and even increased the rate of production. Motor oil additives increased the calorific value minimally. In order to produce the wood pellets with desired physical and thermal characteristics, a suitable additive with the right biomass material should be used. Valuable information about both the pelletizing process and pellets is necessary in the future when developing good-quality pellets, a prime biofuel, from low-value and/or moist biomass that has undergone a cost-efficient drying process. The results of the experimental measurements and properties of wood pellets with different additives are presented in the final part. This study is promoting the future development of eco and cost-efficient wood-based pellet production in both quantitative and qualitative senses. |
