At this moment, blends with up to 50% of HEFA jet fuel are allowed to be used in commercial passenger flights. Once the HEFA Jet fuel is refined and certified to the ASTM D7566 specification it needs to be blended with fossil jet fuel. More information about certification can be found in the next step of our supply chain.
This blending process can be undertaken at the sustainable jet fuel refinery, a petroleum refinery or at a separate facility. To create a sustainable jet fuel blend that meets the specifications, the blend must contain at least 50% of fossil jet fuel. The 50% blend limit is a precautionary measure enabling the industry to start using sustainable jet fuels, while additional assessments are undertaken on the need to maintain required levels of aromatic content in fuels.
Aromatics are absent in the HEFA and Fischer Tropsch fuels and this currently restricts the use of sustainable jet fuels to a 50% blend in order to guarantee aromatic content of the final sustainable aviation fuel (SAF) blend. Once blended, the sustainable jet fuel blend is sampled and analyzed to confirm that the blend stocks have mixed well and the SAF blend meets the specifications.