Integrated Biochar Systems: Engineering, Economics, Material Specification, and Adoption Across Global Contexts

This dissertation examines biochar systems across technology, economics, material specification, and adoption in the United States Corn Belt and Ghana. Biochar is a carbon-rich material produced by heating biomass under oxygen-limited conditions and is increasingly promoted for soil improvement, carbon dioxide removal, residue valorization, and circular bioeconomy development. However, practical adoption depends on more than biochar’s potential; it requires affordable and reliable production technologies, locally appropriate economics, clear material specifications, and extension systems that move knowledge into practice.The first part of the dissertation evaluates three low-cost, farmer-scale biochar kilns in the United States: an open flame-curtain kiln, a controlled-draft flame-curtain kiln, and an indirect-heat retort. Field trials showed that kiln architecture strongly influenced biochar yield, operating temperature, processing time, and repeatability. A companion techno-economic analysis demonstrated that labor cost and operator time strongly shape production economics under United States conditions.The second part extends the analysis to Ghana under humid tropical conditions. Field experiments and techno-economic assessment showed that kiln performance, feedstock behavior, fabrication cost, labor cost, and capital constraints interact differently in Ghana than in the United States. These chapters demonstrate that biochar technology rankings are context-specific and cannot be transferred uncritically across economic and production environments.The third part develops an application-specific biochar engineering framework. This framework emphasizes that no two biochars are the same and that feedstock, pyrolysis conditions, and post-processing should be selected according to intended use, especially for water remediation and soil health applications.The final part focuses on extension and adoption. It documents a community-engaged biochar training program in Ghana and analyzes the Biochar Innovators Society as a digital extension platform for biochar education and early adoption. Overall, the dissertation argues that realizing biochar’s potential requires aligning engineering design, economic feasibility, material performance, and user-centered extension with local context.