Monday, April 30, 2007

Environmental impact assessment of Integrated Biomass Supply Analysis and Logistics (IBSAL) model

Sudhagar Mani, Biological and Agricultural Engineering, University of Georgia, Driftmier Engineering Center, Athens, GA 30602 and Shahab Sokhansanj, Envionmental Sciences Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831.

Integrated biomass supply analysis and logistics (IBSAL) is a simulation model to estimate the cost and energy use of different biomass supply options to a large scale biorefinery. In order to select the best supply options, environmental impacts of the supply systems are very important apart from the cost and energy use. Knowledge of environmental and health impacts due to the emissions is essential to meet the local environmental regulations/standards for a biorefinery. This analysis can compare alternative choices, identify points for environmental enhancement, and provide support information for decision makers, who can have opportunities to improve the existing systems. This paper presents the detailed assessment of environmental impacts of collecting corn stover from the field to delivering it to a biorefinery. The supply and delivery options in the form of square bales, loafs and dry chops were used in this analysis. Fossil fuel (diesel) consumption of each collection and transport operation was calculated using IBSAL model. The fuel consumption rate was used to estimate the environment emissions using average emission factors published in the literatures. The environmental impacts of the emissions were assessed based on climate change, acid rain formation, smog formation and human toxicity impact potentials.  The environmental impacts due to diesel fuel use can potentially be minimized, if all the biomass collection and transport machineries use bio-diesel as a fuel.