KRAFT LIGNIN AS AN ADDITIVE IN PINE AND EUCALYPTUS PARTICLE COMPOSITION FOR BRIQUETTE PRODUCTION

ABSTRACT The objective of this study was to evaluate the properties of briquettes produced with different proportions of pine and eucalyptus wood, as well as to characterize the potential of kraft lignin as an additive in the composition of briquettes for energy generation. The treatments differed from one another in the pine and eucalyptus wood particle ratios (0, 25, 50, 75 and 100%), as well as for the kraft lignin content (0, 2, 4, 6, 8, 10, and 12%). The biomasses were characterized by their physical and chemical properties, and briquette properties were evaluated according to apparent density, lower calorific value (LCV), energy density, and maximum burst load. The results showed an increase in the apparent density as the proportion of lignin and eucalyptus in the briquettes increased. The particle composition of the briquettes had a higher influence on the energy density increase compared to the addition of kraft lignin, being more significant in briquettes produced with higher proportions of eucalyptus. It was also observed that the addition of lignin increased the resistance to the rupture load, and that there was a specific value at which this resistance was higher (at 7% or 11% of lignin, depending on the proportion of particles). Additionally, the briquettes made with 100% pine achieved greater mechanical resistance. In general, kraft lignin presented good potential for use as a briquette additive, contributing to improved energy and mechanical properties.

摘要 本研究旨在评估不同配比松木与桉木制备的压制块（briquettes）的性能，并表征硫酸盐木质素（kraft lignin）作为添加剂用于发电用压制块配方的潜力。实验处理组的差异体现在松木与桉木颗粒配比（0、25%、50%、75%、100%）以及硫酸盐木质素添加量（0、2%、4%、6%、8%、10%、12%）两个维度。对受试生物质进行了物理与化学性质表征，并针对压制块的表观密度、低热值（lower calorific value, LCV）、能量密度以及最大破裂载荷进行了性能评测。结果显示，随着压制块中木质素与桉木占比提升，其表观密度随之升高。相较于硫酸盐木质素的添加，压制块的颗粒配比对能量密度提升的影响更为显著，且在桉木占比较高的压制块中该效应更为突出。同时研究发现，木质素添加可提升压制块的抗破裂载荷性能，且存在使该性能达到最优的木质素添加量（7%或11%，具体取决于颗粒配比）。此外，100%松木制备的压制块展现出更优异的机械强度。总体而言，硫酸盐木质素作为压制块添加剂具备良好的应用潜力，可有效改善压制块的能量与机械性能。