The economic and environmental sustainability of converting Miscanthus to hydrocarbon biofuel by pyrolysis and catalytic hydrotreatment

Abstract

Utilization of high-quality biomass resources such as Miscanthus is considered an effective way to alleviate energy shortages and develop a low-carbon energy economy. In this work, the economic benefits and environmental impacts of producing hydrocarbon biofuel by fast pyrolysis and catalytic hydrotreatment from Miscanthus were investigated, along with the differences in the utilization of biochar: combustion for heat supply (HS), soil amendment (SA) and upgrading to activated carbon (AC). The hydrocarbon biofuel mass yields of up to 23.3 % for all scenarios. The SA scenario had the lowest selling price of 6.89 Chinese Yuan (CNY) per liter. The HS scenario had the lowest total GHG emissions and fossil energy requirement (FED) of 19.2 gCO2e/MJ and 0.615 MJ/MJ, respectively. The AC scenario had the best net GHG emissions of −46.2 gCO2/MJ due to the replacement of the coal-based activated carbon pathway, but the higher energy consumption and capital investment limit its economic performance. Sensitivity analysis showed that fuel output had the most significant economic and environmental impacts. Optimizing the financing cost and system energy supply was a feasible and effective way to improve the economic and environmental sustainability of the bio-energy plant.