The role of lignin in the densification of torrefied wood in relation to the final product properties

The results of the tests and analyses indicate that torrefied softwood should be densified immediately after production. Furthermore, pellet quality of the torrefied material was found to depend on the binding ability of its lignin in the presence of moisture during densification. Additionally, storage of torrefied spruce prior to densification causes reduced binding ability of its lignin leading to pellets of lower quality.