Deployment of a Geographical Information System Life Cycle Assessment Integrated Framework for Exploring the Opportunities and Challenges of Enhanced Oil Recovery Using Industrial CO2 Supply in the United States

This paper integrated the life cycle assessment (LCA) approach with a geographical information system (GIS) in order to compare greenhouse gas (GHG) emissions in the enhanced oil recovery (EOR) process, utilizing carbon dioxide (CO2) from three industrial pathways. Pathway 1 is a corn-based ethanol plant with carbon capture and sequestration (CCS), while pathways 2 and 3 are coal-fired and natural gas-fired power plants, respectively, with amine-based postcombustion CCS technology. The pathways were compared to a conventional crude recovery, transport, refinement, and end-use combustion baseline, which had net GHG emissions of 0.47 tCO(2)-e/bbl. Overall, net GHG emissions from pathways 1, 2, and 3 were lower than in the baseline case. In this LCA study, the system expansion approach was applied and the results indicated that ethanol-based CCS-EOR was notably the better alternative. However, the CO2 supply from ethanol plants is limited; they would have the capacity to produce only about 25 000 bbl/d, compared to 1.1 Mbbl/d in pathway 2 and 125 000 bbl/d in pathway 3. Among the system processes assessed, the CO2 injection system process has the greatest influence on the LCA results, where the magnitude of the reduction in GHGs depends on each site's specific crude recovery rate and that determines the extent of the displacement credits for coproducts. This finding indicates that crude oil with lower carbon intensity can be produced from EOR reservoirs that are less efficient in terms of crude recovered per ton of CO2 injected. However, it should be acknowledged that using less efficient reservoirs would be associated with greater CO2 supply which has a parasitic energy requirement and would in turn entail a higher cost burden.