Energy Security
Coal-to-Liquids Create Ultra-Clean Fuels
With global energy consumption projected to increase 70 percent by 2030 and oil imports likely to reach 62 percent, according to the U.S. Energy Information Administration, greater use of coal for energy security makes more sense now than ever. And the process is competitive at oil prices of $40 to $50 per barrel. Today's prices hover around $90.
Btu Conversion technologies allow coal to be turned into clean electricity, natural gas and
transportation fuels, and technology is being advanced to capture and store carbon dioxide.
Coal-to-liquids (CTL) technology converts coal to transportation fuels such as high-performance jet fuel and ultra-low sulfur diesel fuel.
The U.S. Department of Defense is studying the advantages of CTL fuels to serve U.S. armed forces on the ground and in the air. As the nation’s single largest energy user, the U.S. military has set a goal to obtain 70 percent of its aviation fuel from domestic, coal-based sources. The U.S. Air Force also is calling for 50 percent of its fuel needs to be derived from CTL by 2016 and recently certified Fischer-Tropsch fuels for use in B-52s.
Several studies support the call for CTL production. In its “American Energy Security” study, the Southern States Energy Board (SSEB), a consortium of governors and state legislators, calls for producing 5.6 million barrels a day of coal-to-liquids fueled by about 1 billion tons of U.S. coal per year.
Converting coal’s energy into other sources starts with technologies using advanced combustion or gasification.
Coal-to-Liquid Fuels Are Created Using Fischer-Tropsch Technologies
| Step 1 – The coal-to-liquids process utilizing Fischer-Tropsch (FT) technology, is a three-step method. First, commercially available gasification technology is used to convert coal into a synthesis gas comprised of hydrogen and carbon monoxide. | Step 2 – After gasification, the syngas is treated to remove sulfur, carbon dioxide and other impurities. Next, the syngas is fed into a FT reactor containing catalyst where it is converted into base liquid fuels and waxes. Each plant is designed to separate carbon dioxide, which could be captured for sequestration or for another beneficial use. | Step 3 – The base fuel and waxes are then upgraded using hydrogen, which creates ultra-low sulfur diesel or jet fuel. The final product is cleaner than conventional diesel because sulfur, mercury and oil byproducts are removed during the first step of the process. The technology will yield about 75 percent diesel fuel, with about 25 percent naphtha used for chemical feedstock. |
Once coal is gasified, it can be turned into diesel fuel and jet fuel through Fischer-Tropsch (FT) technologies, and technologies are also available to convert gasified coal to synthetic natural gas and hydrogen.
A plant using more than 6 million tons of coal annually could produce more than 3.6 million barrels per year of diesel and naphtha annually. The U.S. Energy Information Administration projects that by 2030, global CTL production will top more than 135 million barrels per year of refined product.