(604j) Carbon Footprint Analysis of Hydrotreated Renewable Jet (HRJ) from Rapeseed in Rotation with Wheat

Authors: 
Ukaew, S., Michigan Technological University
Shonnard, D. R., Michigan Technological University
Lewis, K. C., U.S. Department of Transportation, John A Volpe National Transportation Systems Center
Archer, D. W., U.S. Department of Agriculture, Agricultural Research Service
Lee, J. H., U.S. Department of Agriculture, Agricultural Research Service

Hydrotreated Renewable Jet (HRJ) is a hydrocarbon “drop-in” biofuel derived from plant oils or fats through a catalytic hydroconversion process. Rapeseed (Brassica Napus) is a favored candidate feedstock for HRJ because of its high quality oil, high oil content, and the potentially attractive agroeconomic benefit to replace the fallow period in wheat/fallow rotations in the Great Plains. The goal of this research is to conduct a carbon footprint analysis of rapeseed HRJ in multiple locations in 10 U.S. states with a “cradle to grave” scope based on the function unit of 1 MJ of energy content in the HRJ fuel. In this study, a set of software tools are being used to simulate processes over the biofuel life cycle; soil biogeochemical processes and supply chain transportation logistics, while other inputs are coming from engineering calculations for HRJ conversion. The interactive Environmental Policy Integrated Climate (iEPIC) model, a biogeochemical based model, is being used to simulate the regional effects of soil types, weather, management practices, fuel use at farm, and cropping system of rapeseed cultivation in rotation with wheat on crop yield, soil organic carbon changes, and N2O emissions. The Alternative Fuel Transportation Optimization Tool (AFTOT) is being used to create supply chain transportation routes for moving rapeseed feedstock at regional farming locations to biorefineries and finally to HRJ distributions based on the lowest cost of transportation. After recovery from rapeseed, rapeseed oil is converted into HRJ fuel through the UOP/Eni Ecofining™ Process, which is the combination of hydrodeoxygenation, decarboxylation, hydroisomerization, hydrocracking, and separation processes. The inventory of inputs (i.e., cultivation, oil extraction and HRJ fuel conversion, and transportation) from multiple landscape scales obtained from the iEPIC model, UOP/Eni Ecofining™ Process, and AFTOT are incorporated to produce robust analysis of regional variations in carbon footprint for rapeseed-derived HRJ. The LCA study and results are compared to the U.S. average fossil jet fuel pathway to determine savings of GHG emissions.