The potential of coprocessing biogenic feedstocks as a way to decarbonize refineries and produce Lower-Carbon-Intensity Jet Fuel (LCJF)

All of the SAF/biojet fuel that is used today is produced via the Hydroprocessed Esters and Fatty Acids (HEFA) or lipid-to-biojet route, in “stand-alone” biorefineries that use lipids as the feedstock. However, coprocessing of biogenic feedstocks also provides a way to make lower-carbon-intensity jet fuels (LCJF) while decarbonising the refinery, the fuels that are produced and making use of established supply chains. Currently, there are not enough lipids available to meet the aviation sector's decarbonisation targets set by groups such as IATA, ICAO, IEA, etc., never mind other components of the transportation sector or “traditional” lipid markets. Therefore, other lower-carbon-intensive (CI) feedstocks, such as biomass-derived “biocrudes”, will be needed to supplement the lipids that are currently used. However, all biocrudes have a complex chemical composition, with some containing as much as 40 wt% oxygen/water, all tending to be less stable, containing higher levels of organic acids and, when coprocessed, result in excess heat and increased coke formation. Each of these issues still have to be resolved to provide the volumes of low-CI aviation fuel that will be needed. Despite these challenges, coprocessing of biogenic feedstocks is likely to be the best way to produce-and-use LCJF fuels.