(58b) Evaluation of Fuels Produced Via the Fischer-Tropsch Process for Use in Aviation Applications

The need to secure sources for the domestic production of liquid hydrocarbon fuels has been a growing concern for the United States (U.S.). The U.S. is heavily dependent on foreign sources for crude oil; many of which are located in unstable regions of the world. Combined with competition for energy sources by developing nations, these factors could have significant logistical and economic implications for the U.S. In particular, the Department of Defense (DoD) is concerned how this situation could affect the ability of the military to respond to worldwide situations. Development of a process and an infrastructure to produce liquid fuels using domestic feedstocks could assist to alleviate the current situation and provide security in the future. Specifically, the production of jet fuels for aviation applications is of interest due to the relatively large quantities required by DoD.

The U.S. has vast resources of solid and non-conventional hydrocarbon reserves. It is believed there are approximately 800 million barrels of oil equivalent in its coal reserves and approximately 1 trillion barrels of unconventional oil in oil shale. These domestic sources make up more than three times the potential than known Middle East reserves. Coal is of specific interest for use since an infrastructure already exists for mining, handling and transportation of this feedstock. It is possible to produce liquid hydrocarbon fuels from non-crude sources via the Fischer-Tropsch (FT) process. FT technology has existed for decades and has been used to produce fuels ranging from gasoline to diesel from sources such as natural gas, coal and biomass. However, several key operating parameters require further development and evaluation prior to successful implementation at large-scale. These parameters include: optimizing the process for coal as the feedstock, maximizing the yield and selectivity to the desired jet fuel product, and minimizing undesired emissions and by-products during production. Most importantly, the jet fuel produced via the FT process must be compatible for use with legacy aircraft as well as next-generation platforms. Therefore, evaluation of the fuel product for use on these applications is of significant importance.

The DoD, working in conjunction with the Department of Energy, has been working to develop, test, certify and use jet fuels produced form coal. Recent research and development activities have been focused on evaluation of the FT fuels, both neat and in blends with conventionally-derived petroleum fuels, for use as replacement/supplement jet fuels. Specific efforts have included evaluation of related physical and chemical properties, thermal stability characteristics, gaseous and particulate combustion emissions, and fit-for-use properties. Results from aspects of this work will be presented and implications related to potential implementation of these fuels will be discussed.