Applying the Life Cycle Assessment to the Use of Biochar from Vine Pruning Waste as an Additive in Mortar

The agricultural industry and corresponding waste materials represent a potential research area for applying circular economy strategies. This research is a life cycle assessment of the addition of different mass percentages (0.47%W, 1.52%W and 2.27%W) of biochar made from vine pruning waste to mortar mixes. The research involves two scenarios. Scenario I is an attributional approach, aligned with the Environmental Product Declaration and Carbon Footprint standards. Scenario II takes a consequential approach, including biochar removals, as well as products and materials avoided as a result of the decision to start using this additive in mortar. The key findings differ substantially. For instance, under the impact category of Potential Global Warming compared to the reference mortar (without biochar additive) (0.58 kg CO2 eq), Scenario I yields a 56.85% increase in emissions (+2.21 kg CO2 eq) for the 1.52%W mix. By contrast, under Scenario II, the same alternative mixture yields an environmental benefit with a 76.83% decrease in emissions (−0.45 kg CO2 eq). This research highlights the environmental benefits of reusing agricultural waste specifically in the construction sector and provides an example of a circular economy study.