Effect of bed material, lignin content, and origin on the processability of biomass in fast pyrolysis reactors

Lignin has great potential for the production of valuable aromatic compounds and has attracted considerable attention. The development of high value applications for Kraft lignin would boost the profitability of pulp and paper operations. A potential solution is the pyrolytic conversion of lignin to valuable liquids and solids. However, Kraft lignin is a thermally sensitive powder which tends to agglomerate under pyrolysis conditions. A mechanically fluidized reactor (MFR) can be used to monitor both the generation of vapours and gas during pyrolysis and how cohesive a feedstock becomes when pyrolyzed. The MFR was, therefore, used to evaluate alternative solutions to improve Kraft lignin behaviour by mixing it with non-problematic feedstocks or by modifying its bed material. Finally, Kraft lignin behaviour and products were compared to those of hydrolysis lignins from different origins.