Safety, health, and environmental assessment of bioethanol production from sugarcane, corn, and corn stover

Abstract

Biofuels as renewable resources are one of the options to meet the challenges of fossil fuel resource depletion and atmospheric pollution. Several studies have focused on the technical, economic, and environmental footprint of biofuels, particularly bioethanol production. However, there has been little effort to incorporate the environmental, health, and safety (EHS) hazards in an inclusive sustainability assessment of bioethanol production alternatives. This study focuses on these sustainability aspects for bioethanol production by employing the EHS and the inherent safety index (ISI) methods. The multicriteria assessment also includes the cumulative energy demand as a widely used lifecycle impact assessment indicator. Sugarcane, corn, and corn stover are considered as biomass resources, and the typical process conditions are used for the base case evaluation. Sensitivity analysis is used to investigate the impact of process conditions, composition of feed, and method settings on the final outcome. The results indicate that both the ISI and the EHS methods present similar overall rankings with sugarcane-derived and corn stover-derived processes as the most and the least hazardous, respectively. However, dissimilarities occur in the evaluation of the process sections, highlighting different hazardous aspects. Finally, including the lifecycle impact assessment in a bicriteria assessment indicates the sugarcane-derived process as clearly superior followed by the corn-derived and the corn stover-derived processes.