1. A Comparison of S8, Sasol IPK, and Jet A Fuels to Determine the Possibility of Alternate Fuels in the Aerospace Industry
Scott Dyke1, Martin Muiños2, and Dr. Valentin Soloiu3
Undergraduate Student 2. Graduate Student 3. Combustion and Emissions Professor
Department of Mechanical Engineering , Georgia Southern University, Statesboro, GA USA
INTRODUCTION
ECONOMIC NEED FOR ALTERNATIVES
VISCOMETER RESULTS
In this study, Sasol IPK and S8 were compared to Jet A in hopes of uncovering new alternative jet fuels.
S8, Sasol, and Jet A were tested with a viscometer, calorimeter, and TGA-DTA to determine if they possess similar properties that would allow these fuels to be considered as viable alternative jet fuels.
Jet A is the most common and most used jet fuel today, Jet A is usually used only in the United States, while Jet A-1 is the standard fuel for the rest of the world.
Sasol IPK is a synthetic kerosene derived from coal.
S8 is a synthetic kerosene derived from natural gas.
Calorimeter testing reveals the lower heating value of fuels in MJ/kg. This value determines the energy content of the fuels.
Viscometer tests determine the viscosity of the fuels in cP, showing the thickness of the fuel and its resistance to flow.
TGA-DTA determines at what temperature the fuel combusts, as well as when the reactions of the fuel alternate between endothermic and exothermic reactions.
In the U.S. alone, over 10 billion gallons of jet fuels have been consumed by airlines in each of the past 15 years with some years over 13 billion gallons used.
The total usage of jet fuel in the U.S. in 2009 was 20.2 billion Gallons.
Fuel costs have increased from $.80/gallon in 2000 to over $2.85/gallon in 2014.
In 2010, world jet fuel consumption was 5, barrels per day or over 163,000 gallons per day.
CONCLUSION
Each fuel was tested through three methods: calorimeter, viscometer, and TGA-DTA.
Through calorimeter testing, both Sasol IPK and S8 have a lower heating value approximately 1 MJ/kg higher than Jet A.
At a temperature of 26 degrees Celsius, Jet A has the highest viscosity of approximately 1.38 cP, while S8 has a viscosity of 1.33 cP, and Sasol 1.11 cP.
These fuels will most likely be used in aircraft applications meaning temperatures will likely be lower than 26 degrees Celsius due to higher altitude and lower pressures; therefore, viscosity will likely increase slightly due to temperature changes.
TGA-DTA results show that each fuel undergoes clear endothermic and exothermic reactions throughout the course of the test. Jet A is nearly all vaporized by 200 degrees Celsius while S8 is nearly all vaporized at around 250 degrees Celsius, and Sasol is nearly all vaporized around 170 degrees Celsius.
These fuels, while differing in some aspects, post similar results on all three tests and both Sasol IPK and S8 seem to potentially be viable alternative fuels.
OBJECTIVE
SASOL IPK AND S8
The goal of the study is to determine whether or not Sasol and/or S8 are capable of serving as alternative jet fuels to decrease America’s dependence on foreign oil.
Sasol IPK is a synthetic fuel produced through a Coal to Liquids (CTL) process. Iso-paraffinic kerosene, IPK, is a stream of synthetic fuel with a small percent of n-paraffins and no aromatics. Paraffins are major components of natural gas and petroleum, with n representing an integer. Aromatics are organic compounds such as benzene; low aromatic means that the fuel is lower in content of these compounds and is designed to reduce petrol sniffing and its effects. Sasol IPK is used by the company Sasol to blend their semi-synthetic jet fuel. It has been approved and supplied at Tambo International Airport since July 1999.
S8 is a synthetic fuel derived from natural gas. This fuel was developed for the U.S. Air Force by Styntroleum to demonstrate that synthetic fuels could be developed and meet jet fuel standards.
TGA-DTA RESULTS
FUTURE WORK
Calorimeter RESULTS
Future work will delve into more comparison tests between these fuels as well as a closer look into the economics of alternative fuels as well as testing each fuel in a small gas turbine engine.
ACKNOWLEDGMENTS
Fuel Type and Trial Number
Fuel Mass (g)
Mass of Wire Before (g)
Mass of Wire After (g)
Change in Mass of Wire (g)
Energy from Wire (Calories)
Gross Heat (MJ/kg)
Lower Heating Value (MJ/kg)
Jet A 1
0.52
11.466
41.875
Jet A 2
13.09
41.218
Sasol IPK 1
13.552
41.574
Sasol IPK 2
0.50
0.0158
0.0068
0.0090
12.6
43.636
S8 1
13.706
43.53
I would like to acknowledge Martin Muinos, Tyler Naes, Remi Gaubert, Julia Heimberger, and Dr. Valentin Soloiu for the assistance in this project.
REFERENCES
The TGA graph displays the mass vaporization rate while the DTA graph displays the temperature at which the sample undergoes endothermic and exothermic reactions. The negative peak of the DTA graph defines the point at which the reaction is endothermic while the positive peak defines the point at which the reaction in exothermic.
“Airline Fuel Cost and Consumption (U.S. Carriers-Scheduled) January 2000-February 2015.” U.S. Department of Transportation .Accessed 21 Apr <
Moses, Clifford A. “Comparative Evaluation of Semi-Synthetic Jet Fuels.” Sept
“World Jet Fuel Consumption by Year.” Figure. <
“Jet Fuel Price in 2012 $.” Figure. < >
CONTACT INFORMATION
Dr. Valentin Soloiu
Scott Dyke-