Techno-Economic Analysis and Carbon Footprint Assessment of Gasification based Green Methanol Production from Diverse Biomass Residues in China

Abstract

Biomethanol is widely considered as an important feedstock for net-zero fuel and chemical production in the carbon-constrained world. Yet the diversity of technology-feedstock combinations during biomethanol production makes it difficult to predict its economic feasibility and carbon intensity. Here, we present an integrated assessment method combining process modeling, techno-economic analysis, and carbon footprint assessment, to quantify the economic feasibility and the carbon footprint of biomethanol through different gasification-based production routes. The minimum selling price and well-to-gate life-cycle greenhouse gas intensity of biomethanol are estimated at $429-879/t and 5.5-32.5 gCO2e/MJ, respectively. For bio-methanol production, steam gasification is more effective than oxygen gasification, as it exhibits lower process-induced CO2 emissions and generates syngas that is more conducive to methanol synthesis. When integrated with carbon capture and storage (CCS), biomethanol production can even achieve carbon negativity (-32 to -94 gCO2e/MJ), while the production cost increases to $484–947/t. Interestingly, integrating CCS actually reduces the decarbonization cost of biomethanol by $13–122 per ton of mitigated CO2e, as the benefits from enhanced decarbonization performance can offset the incremental costs associated with the CCS process. Overall, this work presents a comprehensive analysis encompassing the diversity of biomass feedstocks, the impacts of gasification agents, and the integration of the CCS process, thus delivering updated insights into the advancement of biomethanol production.