Abstract of the 2024 TJ Best Research Paper:

Circularity is creating momentum toward using waste feedstock in a myriad of applications. The paper industry is no exception—packaging products made from agricultural or agro-industrial residues are receiving more attention now than ever. Negative consumer perceptions of tree felling are also speeding the acceptance of waste fibers.

Nevertheless, adopting these residues raises the issue of whether they constitute a better alternative to fight climate change than wood. Answering this question is imperative to ensure that packaging manufacturers meet their pledges to reduce carbon footprints.

This study aims to estimate the carbon footprint of corrugating medium and linerboard containing wheat straw and sugarcane bagasse pulp compared to analogous wood-based materials. The goal was also to understand how methodological decisions to allocate emissions to nonwood residues can affect the results. This study includes a “cradle to grave” life cycle carbon analysis that comprises stages for residue production, pulping, papermaking, waste management, and corresponding transportation.

Results suggest that straw- and bagasse-based medium and linerboard can present a higher carbon footprint than products made from virgin and recycled wood fibers. The main driver is the production of nonwood chemi-mechanical pulp. In addition, the lower capacity of nonwood residues to be recycled increases the overall impact. Finally, decisions around emissions allocation highly influence the results.

This study helps mitigate part of the uncertainty around the environmental sustainability of corrugating medium and linerboard made from the selected nonwood residues, helping mills to make informed decisions regarding their use.