Agricultural Waste Valorisation through Anaerobic Digestion in South Africa: A Scoping Review

This scoping review aims to systematically map and synthesise the available evidence on agricultural waste valorisation through anaerobic digestion in South Africa. The review will examine the types of agricultural waste investigated, anaerobic digestion technologies and configurations, operating conditions, co-digestion and pretreatment strategies, biogas and methane production, biogas upgrading and purification, digestate utilisation, environmental and economic outcomes, implementation barriers, policy and institutional factors, and identified research gaps. The review will follow the Joanna Briggs Institute methodological guidance for scoping reviews and will be reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR). Evidence published between 2015 and 2025 will be considered, together with relevant grey literature from South African institutional and governmental sources. The review is intended to provide an evidence map that can inform future research, technology development, resource-recovery strategies and circular-bioeconomy implementation in South Africa.