The impacts of biomass properties on pyrolysis yields, economic and environmental performance of the pyrolysis-bioenergy-biochar platform to carbon negative energy

• Published in: Bioresource technology 2017-10, Vol.241 (C), p.959-968
• Main Authors: Li, Wenqin, Dang, Qi, Brown, Robert C., Laird, David, Wright, Mark M.
• Format: Article
• Language: English
• Subjects: Agriculture; Biofuels; Biomass; Biotechnology & Applied Microbiology; Carbon; Carbon negative energy; Charcoal; Energy & Fuels; Fast pyrolysis; Life cycle analysis; Techno-economic analysis
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2017.06.049

•Predicted pyrolysis yields for 346 feedstocks using a regression model.•Evaluated impacts of biomass ash content and O/C ratio on pyrolysis product yields.•Estimated pyrolysis biofuel prices ranged from $2.5 to $5 per gallon.•Calculated greenhouse gas emissions ranged from −10 to 250g CO2/MJ of fuel.•Modeled a carbon negative energy system with pyrolysis-bioenergy-biochar. This study evaluated the impact of biomass properties on the pyrolysis product yields, economic and environmental performance for the pyrolysis-biochar-bioenergy platform. We developed and applied a fast pyrolysis, feedstock-sensitive, regression-based chemical process model to 346 different feedstocks, which were grouped into five types: woody, stalk/cob/ear, grass/plant, organic residue/product and husk/shell/pit. The results show that biomass ash content of 0.3–7.7wt% increases biochar yield from 0.13 to 0.16kg/kg of biomass, and decreases biofuel yields from 87.3 to 40.7 gallons per tonne. Higher O/C ratio (0.88–1.12) in biomass decreases biochar yield and increases biofuel yields within the same ash content level. Higher ash content of biomass increases minimum fuel selling price (MFSP), while higher O/C ratio of biomass decreases MFSP within the same ash content level. The impact of ash and O/C ratio of biomass on GHG emissions are not consistent for all feedstocks.