Production of a nutrient enriched biochar : a techno-economic feasibility analysis

Abstract

A techno-economic feasibility analysis was conducted for a biomass pyrolysis plant that utilized Eucalyptus to produce fertilizer-enriched biochar. Key parameters – biomass throughput, fertilizer loading, and selling price – were optimized for financial viability using net present value (NPV), internal rate of return (IRR), return on investment (ROI), and payback period (PP). Four case scenarios were assessed, focusing on energy and co-product utilization, particularly pyrolysis oil for herbicide production and synthesis gas for electricity generation. Results show that Scenario 2 (electricity generation from synthesis gas and wood vinegar combustion, with separate sale of the phenolic fraction) and Scenario 4 (separate sale of both wood vinegar and phenolic fractions) may be profitable, though their low IRR (1.1%) could deter investment. Optimization indicated that increasing biomass feed rates and reducing the fertilizer-to-biomass ratio may enhance economic outcomes. However, the high cost of enriched biochar relative to conventional fertilizers poses a significant challenge to both short- and long-term economic feasibility. These findings underscore the need for innovative strategies to improve the economic viability of biochar and to support its adoption among agricultural stakeholders.