Synthetic fuel, also known as synfuel or Fischer-Tropsch liquids, is a type of manmade diesel and jet fuel that is made from coal, natural gas, or biomass. It is classified into three types: CTL, or coal to liquid, GTL, or gas to liquid, and BTL, or biomass to liquid.
CTL is much cleaner and has lower emissions than normal petroleum or oil. Synthetic plants don’t ignite coal like normal coal plants. Instead they gasify coal, which sets off a reaction creating syngas, a mixture of gases that can be created into liquid fuel. Plants that use syngas are know as Integrated Gasification Combine Cycles (IGCC). These plants are among the cleanest electricity generators. No pollutants are sent into smokestacks into the atmosphere. When coal becomes gas, impurities like mercury and sulfur are “stripped out of the gas stream”, instead of being released into the air. The fuel resulting from IGCC plants burn free of pollutants. Sulfur-free fuel equals less smog and acid rain, so synfuel is actually a benefit for the environment.
The IGCC gasification process also allows carbon dioxide to be easily removed from the waste stream. Once removed, it can be buried deep in the earth. This burying of CO2 is called carbon capture and sequestration, and is supported by environmental scientists, especially those who fear global warming. In fact, oil fields use this CO2 to “revive depleted oil wells”, pushing the gas underground with great pressure, forcing leftover oil to be raised to the surface. This process is known as enhanced oil recovery (EOR). EOR allows CO2 to stay deep within earth and stabilize with the rock and water below.
GTL fuel is considered to be the most cost effective alternative fuel. It is colorless, sulfurless, odorless, and can be combined with regular oil. Natural gas is partially oxidized to create syngas, a combination of carbon monoxide and hydrogen. The syngas is then converted into liquid hydrocarbons, using the Fisch- Tropsch synthesis. Lastly, the liquid hydrocarbons become synfuel. GTL can be used with all vehicles fitted with a TDI engine, requiring no “fixups”. It also has a high cetane number, meaning that fuel efficiency as well as engine performance can rise.
Biomass to liquid synfuel begins with the drying and grinding of biomass, which is made into pellets. These pellets are made into a gas called smouldering gas and solid fraction charcoal at a low temperature gas process, then transformed into a synthetic gas. The gas is then liquefied in a Fischer Tropsch reaction, where carbon monoxide and hydrogen from carbo-hydro chains. The result is isomerized to increase stability and then distilled or hydro-treated. In this step, the fuel must be fine tuned to suit its needs. BTL doesn’t release greenhouse gases, is free of aromatics, and is low in sulfur. It is lubricant, reducing wear and tear on machine parts, especially the engine.
The synjet, or synthetic-fueled jet, is what the world of aviation is leaning towards. Since synthetic fuel is created and works similar to petroleum, it is the ideal choice for planes. Other alternative fuel sources such as hydrogen, compressed air, and alcohol are not strong enough, nor will last long enough, for flight. America also has vast reserves of coal, unlike oil.
Already countries such as South Africa make 300,000 barrels of synfuel a day. Other countries, such as Malaysia and Qatar are investing in synfuel production. There is an increased global demand for oil, making synfuel an economically good alternative.
Recently the Office of Defense issued a Clean Fuels Initiative, a proposal to run all battlefield machines on synfuel. This will allow the military to avoid buying oil from unstable countries, (such as Venezuela, whose president is threatening to cut of America’s oil supply, crashing our economy), meet clean air requirements in Europe, simplify battlefield equipment (machines currently run on multiple fuels), and stay away from oil supply vulnerabilities (like earthquakes and hurricanes).
The Airbus A380 super jumbo, the world’s largest passenger aircraft, flew from Britain to Los Angeles on February 1st, 2008. One of the plane’s four giant engines was powered with synfuel. A report from the pilots stated that there was “no difference between the regular engines and the GTL engine”. There was also significantly lower amounts of pollutants, such as particulate, carbon monoxide, hydrocarbon, and nitrogen oxide emissions. The synfuel was provided by the oil company SHELL, who said that it is “a clear, clean fuel, virtually free of sulfur and aromatics, and had a very high combustion level.” This flight was a breakthrough in synfuel production.
A B-52 Stratofortress is being tested by the Air Force at the Minot Airbase. The government is wondering how synfuel works under extreme conditions, such as the ice and frost the fuel is now being subjected to.
A controversy involving synfuel revolves around BTL. Many people believe that BTL will force biodiesel out of business. However, in a recent analysis by European biodiesel industries ended in the statement that there “was enough room in the market for both”.
There are both negative and positive effects about using synfuel as an alternate energy source for airplanes.
Harmful emissions from the burning of petroleum do not occur in the use of synfuels. Synfuel doesn’t contain carcinogens, pollutants, or heavy metals. The cost of synfuel is low as well. It only takes about $35 to create a barrel.
Negative things about synfuel include possible instability, but recent testing has almost entirely eclipsed that former belief. In fact, in 2009, the Airbus Company plans to run another plane entirely with synfuel. Another con is that synthetic fuel is not in mass production, and people do not know about it. Current well-known alternative fuels are hydrogen, as in hybrid cars, and biofuels.
