Consequential life cycle assessment of kraft lignin recovery with chemical recycling

Alessandro Marson; Joseph S M Samec; Alessandro Manzardo

doi:10.1016/j.scitotenv.2023.163660

Consequential life cycle assessment of kraft lignin recovery with chemical recycling

Sci Total Environ. 2023 Jul 15:882:163660. doi: 10.1016/j.scitotenv.2023.163660. Epub 2023 Apr 23.

Authors

Alessandro Marson¹, Joseph S M Samec², Alessandro Manzardo³

Affiliations

¹ CESQA (Quality and Environmental Research Center), University of Padova, Department of Civil, Environmental and Architectural Engineering, Via Marzolo 9, 35131 Padova, Italy; University of Padova, Department of Industrial Engineering, Via Marzolo 9, 35131 Padova, Italy. Electronic address: alessandro.marson@unipd.it.
² Stockholm University, Department of Organic Chemistry, Svante Arrhenius väg 16C, SE 106 91 Stochholm, Sweden. Electronic address: joseph.samec@su.se.
³ CESQA (Quality and Environmental Research Center), University of Padova, Department of Civil, Environmental and Architectural Engineering, Via Marzolo 9, 35131 Padova, Italy. Electronic address: alessandro.manzardo@unipd.it.

PMID: 37094672
DOI: 10.1016/j.scitotenv.2023.163660

Abstract

The recovery of kraft lignin from black liquor allows an increasing of the pulp production of a kraft mill (marginal tonnage) and at the same time provide 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 how the use of lignin as energy feedstock is not environmentally advantageous compared to 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.

Keywords: Kraft lignin; Life cycle assessment; Phenol; Pulp; Sulfur recycling.