Wood biomass is used as fuel due to its good energy properties, in the form of pellets, briquettes, chips, and firewood. The raw material for the production of pellets is most often waste from sawmill production and lower-quality wood. However, since the consumption of wood pellets is constantly increasing, alternative materials are being sought. We thus produced pellets from coffee grounds and sawdust in various ratios (100:0, 75:25, 50:50, and 25:75). We determined the quality of the pellets we produced in accordance with the SIST EN ISO 17225 standard: moisture content, bulk density, mechanical durability, ash content, calorific value, and hardness. We compared the results with those for commercially available pellets made exclusively from wood biomass. We found that the quality of pellets decreases as the proportion of coffee grounds increases, and the pellets do not meet the requirements of the highest quality class standard, due to the mechanical durability criterion. Pellets with a higher proportion of coffee grounds achieve higher calorific values. Coffee grounds represent a potential in pellet production, primarily as an additive or admixture to wood biomass, where raw material preparation and the pelleting process need to be optimized.
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