Life-Cycle Greenhouse-Gas Emissions Inventory for Fischer-Tropsch Fuels

This report discusses the development of greenhouse gas (GHG) emissions estimates for the production of Fischer-Tropsch (FT) derived fuels (in particular, FT diesel), makes comparisons of these estimates to reported literature values for petroleum-derived diesel, and outlines strategies for substantially reducing these emissions. This report is the product of the first phase of a comprehensive assessment being conducted by Energy and Environmental Solutions (E2S), LLC, for the National Energy Technology Center (NETL) to characterize the impact, both short and long term, of FT fuel production on the environment and on human health and well-being. This study involved the development of GHG inventories for a number of conceptual FT process designs. It also included the development of preliminary estimates for criteria pollutant emissions. The next phase of this assessment will address life-cycle improvements for FT fuels by targeting specific process changes aimed at reducing GHG emissions. Preliminary results have identified promising reduction strategies and these estimates have been included in this document. Future research will be focused on expanding the current emissions inventory to include a broader range of multimedia emissions of interest to NETL programs, and on performing economic analyses corresponding to the new low-emission FT process designs developed. The analysis presented in this report is limited to a LCI of airborne emissions produced along the FT fuel product life cycle. It is not a complete inventory of all emissions, though it could be used as a starting point for one, since it lays out a formal methodology for conducting an analysis for FT derived fuels. The impact of various greenhouse gases has been considered in relative terms by converting all GHG emissions to a CO2 equivalency basis. The LCI is based on earlier FT plant designs, and no effort has been made to improve on these conceptual designs.