ASTM committee votes to approve biojet fuel in blends up to 50%; final issuance of spec expected by August
An ASTM committee has voted to approve the addition of a new bio-derived jet fuel annex to the alternative jet fuel specification D7566 (Standard Specification for Aviation Turbine Fuel Containing Synthesized Hydrocarbons). The new annex details the fuel properties and criteria necessary to control the manufacture and quality of this new fuel, now referred to as “Hydroprocessed Esters and Fatty Acids” (HEFA) fuel, to ensure safe aviation use.
With the approval of the alternative jet fuel specification for HEFA—sometimes referred to as “hydroprocessed renewable jet” (HRJ) fuel—hydroprocessing of plant oils becomes another pathway for production of alternative jet fuels. Once issued by ASTM, the revised specification will enable use of HEFA fuels from biomass feedstocks such as camelina, jatropha or algae, in combination with conventional jet fuel up to a 50% blend.
This vote effectively concludes the technical review process, allowing for final issuance of the revised specification by August of this year.
The committee endorsement of this specification is significant for all consumers of jet fuel, bringing the airline industry one step closer to of widespread production of cleaner, alternative fuels that will help meet our environmental goals while enhancing the security and competitiveness of our energy supply.
This standard provides another pathway for alternative jet fuel production, and will enable increased commercial production. At the same time, we continue to explore other pathways that may be able to meet the rigorous criteria needed under the jet fuel specification.—Nicholas E. Calio, President and CEO of the Air Transport Association (ATA)
Work undertaken by the Commercial Aviation Alternative Fuels Initiative (CAAFI), which ATA helped co-found in 2006, supported the development of the specification.
Background of the new specification. In 2009, ASTM approved Fischer-Tropsch processing as the first pathway to be covered by its alternative jet fuel specification; the initial version of this specification included Fischer-Tropsch (FT) hydroprocessed synthesized paraffinic kerosenes (SPK) as the first approved synthetic blending component. (Earlier post.)
An initial ballot to add a second Annex to the specification to incorporate Bio-SPK—bio-synthesized paraffinic kerosenes—as a second approved hydroprocessed SPK blending component was circulated to Subcommittee J in May, 2010. The ballot identified these blending components as hydroprocessed SPK from fatty acid esters or free fatty acids.
That ballot was withdrawn due to the submittal of seven negative votes. The new ballot, which received approval, included a draft specification revised to add two new requirements for the HEFA blend component: existent gum and FAME. Both are intended to protect against impurities and trace materials that might result from unanticipated process or feedstock issues.