Kavindi, et al (2024) Assessing GHG Emission Reduction in Biomass-Derived BiocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More Production via Slow PyrolysisPyrolysis is a thermochemical process that converts waste biomass into bio-char, bio-oil, and pyro-gas. It offers significant advantages in waste valorization, turning low-value materials into economically valuable resources. Its versatility allows for tailored products based on operational conditions, presenting itself as a cost-effective and efficient More: A Cradle-to-gate LCA Approach. Resources, Conservation and Recycling. https://doi.org/10.1016/j.resconrec.2024.107900

Biochar has been recognized as an important negative emission technology (NET) for carbon sequestration. However, assessing its true greenhouse gas (GHG) reduction potential requires a comprehensive understanding of both carbon storage and the emissions generated during production. This study uses a life cycle assessment (LCA) to evaluate biochar production, focusing on emissions from slow pyrolysis—a method known to yield significant biochar amounts.

Key factors influencing biochar’s emissions include feedstockFeedstock refers to the raw organic material used to produce biochar. This can include a wide range of materials, such as wood chips, agricultural residues, and animal manure. More type, energy use, and production scale. The study examines emission factors (EFs) across various production scenarios, highlighting the complexity of emissions based on production methods. Emission factors in biochar production can range from -1.10 to 0.68 tons of CO2 equivalent per ton of biochar, depending on specific parameters like carbonization techniques and whether surplus energy is utilized.

In a case study involving crop residues in Japan, annual biochar production from 840,000 tons of residue could reduce GHG emissions by 215,712 to 625,775 tons of CO2 equivalent. This range demonstrates the significant potential of biochar, not just as a carbon sink but as a solution for GHG reduction when surplus energy from biochar production is harnessed.

Accurate LCAs are crucial for integrating biochar into carbon crediting schemes, ensuring that its GHG abatement potential is fully recognized and optimized.