LCA investigation of recovery of kraft lignin increases pulp production

Mistra SafeChem researcher Joseph Samec, Stockholm University, has published an article about how consequential life cycle assessment has been applied to investigate the recovery of kraft lignin and the resulting increase in pulp production.

In this publication, a consequential LCA has been performed on lignin outtake from a pulp mill and compared the environmental sustainability of using the lignin in different applications.

The recovery of kraft lignin from black liquor increases the pulp production of a kraft mill while providing a valuable material that can be used as energy or chemical feedstock. However, because lignin precipitation is an energy- and material-consuming process, the environmental consequences from a life cycle perspective are under discourse. The aim of this study is to investigate, through the application of consequential life cycle assessment, the potential environmental benefits of kraft lignin recovery and its subsequent use as an energy or chemical feedstock.

A newly developed chemical recovery strategy was assessed. The results revealed that using lignin as an energy feedstock is less environmentally advantageous than producing energy directly from the pulp mill's recovery boiler.

However, the best results were observed when lignin was used as a chemical feedstock in four applications to replace bitumen, carbon black, phenol, and bisphenol-A.

Read the article, published in Science of the Total Environment: Consequential life cycle assessment of kraft lignin recovery. External link, opens in new window.

More on this topic

In this review on kraft lignin, the formation and transformation of this feedstock are scrutinized. Also, techno-economical assessment and life cycle assessment of different routes are discussed: Kraft Lignin: A Valuable, Sustainable Resource, Opportunities and Challenges. External link, opens in new window.