January 13, 2023
Economic and Environmental Analysis to Evalulate the Potential Value of Co-Optima Diesel Bioblendstocks to Petroleum Refiners
AbstractThe U.S. petroleum refining sector is undergoing a period of historic transformation, catalyzed by the decarbonization of the U.S. economy. Diesel-boiling-range bioblendstocks, tailored for use in mixing controlled compression ignition (MCCI) engines, have gained traction, owing to their superior fuel properties and environmental performance as compared to traditional petroleum fuels. This work couples linear programming (LP) refinery optimization models with life cycle assessment (LCA) to quantify the potential economic and environmental benefits, and potential trade-offs, of blending diesel-boiling-range bioblendstocks at refineries. LP models were developed in Aspen Process Industry Modeling Systems (PIMS) for three representative petroleum refinery configurations of differing complexity. Seven diesel-boiling-range bioblendstocks: 4-butoxyheptane, 5-ethyl-4-propylnonane, soy biodiesel, sludge hydrothermal liquefaction diesel, polyoxymethylene ethers, renewable diesel, and hexyl hexanoate, were investigated to identify key fuel properties that influence refineries’ economics and to track the effect of adding bioblendstocks on refinery-wide cradle-to-gate GHG emissions. These analyses considered blending levels from 10 to 30 vol% and fuel demand projections over the period 2040 to 2050. This analysis determines that bioblendstock sulfur content and cetane number are the primary fuel attributes with the potential to provide value to refiners. LCA results indicate that the use of MCCI bioblendstocks can reduce cradle-to-gate refinery GHG emissions by up to ~40% relative to conventional refinery operations when considering carbon uptake in the supply chain of the bioblendstock. Refinery-wide marginal GHG abatement costs range from 120 to 3,600 $/Metric Tonne-CO2e avoided across the scenarios evaluated. Reducing the price of bioblendstocks is identified as a key to their adoption.
Published: January 13, 2023