ASTM to Consider Adding 50% F-T Blend to Jet Fuel Specification: Work on Hydrotreated Fats and Oils Also Underway
ASTM International’s Subcommittee D02.J0.01 on Jet Fuel Specifications will consider a ballot to include Fischer-Tropsch-derived synthetic paraffinic kerosene (SPK) for use in blending in jet fuels at levels up to 50% in the jet fuel specification ASTM D1655 when the supporting research report is available, estimated to be later this month.
While ASTM does not approve new aviation fuel formulations—that is the domain of the FAA and the aircraft original equipment manufacturers (OEMs)—it does recognize aviation approvals by incorporating them into specifications. ASTM also is able to assemble diverse experts to advise approval authorities regarding issues relevant to new fuel formulations.
ASTM’s specifications work is organized by technical committee and subcommittee. ASTM Committee D02 on Petroleum Products and Lubricants was formed in 1904, and has a current membership of approximately 1,500 industry professionals and experts with jurisdiction over 580 standards. Subcommittee D02.J is responsible for aviation fuels. It carries out its work in six separate sections:
- Section J01, Jet Fuel Specifications;
- Section J02, Aviation Gasoline;
- Section J03, Combustion and Thermal Properties;
- Section J04, Additives and Electrical Properties;
- Section J05, Fuel Cleanliness; and
- Section J06, Emerging Fuels.
The key sections for the advancement of non-petroleum sources for aviation turbine fuel are Sections J01, J04 and J06.
At the June 2008 meeting of D02.J, the subcommittee considered the issue of the approval of biomass-produced fuels that would help reduce greenhouse gases. In addition to that topic, task force meetings were held to discuss alternate aviation gasoline, improvements and additional fuel quality control procedures.
In addition to preparation for the balloting on the F-T-derived SPK, the J01 meeting noted that the OEM/FAA approval process is under way to expand the definition of acceptable SPK to include hydrogenated fats and oils (HFO). In addition, work has begun to approve the co-processing (by hydrotreating) of fats and oils (that are used primarily to make diesel fuel) with petroleum crude streams that results in small amounts of components in jet fuel, but which have the same composition as typical jet fuel components. This work is also reflected in Section J06.
Sasol fully synthetic jet fuel (FSJF) is expected to be balloted (between July and November) for inclusion in ASTM D1655, as soon as a final piece of documentation is complete, expected to be by mid-July 2008.
Section J06 on Emerging Aviation Fuels is a new start-up group. At the June meeting, they opened with a discussion of the current state of alternative turbine fuels.
The current plans are for this section to help with the modification of ASTM D1655 to identify SPKs as appropriate blend stocks, and to start preparing a new specification for synthesized hydrocarbon turbine fuels, starting with blends of FT derived SPK.
Based on promising data being generated by HFO (hydrotreated fats and oils) researchers, a new task force was formed to develop an approval path for HFO-derived kerosene as a jet fuel blend stream. ASTM expects the approval process is anticipated to be relatively straightforward if the preliminary findings that HFO-derived SPK is very similar to existing FT-derived SPKs holds up to detailed examination.
Preparation of the new specification is the work of a task force group that is part of Section J06.
At the June meeting, a major oil refiner presented information on their renewable diesel produced by hydrotreating fats and oils with diesel fuel. Currently the kerosene fraction that results is disqualified from jet fuel blending because it contains 1-2% of HFO-derived material, which is not yet aviation approved.