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TURNING COAL INTO GAS IN ALASKA
Coal Bin article by Harold Hough Dec/Jan 2010
Cook Inlet Region Inc. (CIRI), a Native Alaskan Company has announced that it intends to build an underground coal gasification (UCG) plant on the west side of Cook Inlet. “Our project we believe is a very exciting one,” Margaret Brown, CIRI president and CEO, told Alaskan politicians. “We have been quietly investigating this project and the technology for a year. We feel we have something to offer the citizens of Alaska.” This will be the first commercial underground coal gasification operation in the United States.
Turning coal into synthetic fuel isn’t new. There are several UCG plants in operation around the world; including India, China, and South Africa. The fuel produced by these plants is called Syngas, and is produced by heating coal with water and oxygen. The result is carbon dioxide, carbon monoxide, hydrogen and methane.
CIRI intends to begin drilling this winter (2009 – 2010) as part of its site evaluation. If permitting goes through as hoped, the company plans to begin construction of its wells and plant in two years. One of the permitting issues is making sure that the coal burn doesn’t pollute any aquifers. Although there are impervious clay layers between the water table and the coal, there is some concern that the depleted coal seam could cave in and create cracks in the clay layer, which could pollute the water table. Since UCG is a new process in Alaska, there is also some uncertainty as to how the permitting process will proceed.
The UCG process requires pumping compressed air into a coal seam deep underground to allow the coal to burn. The heat from the burning converts excess air and the bulk of the coal to Syngas, which is brought to the surface through production wells. In the CIRI project, carbon dioxide produced along with the syngas will be used to improve oil recovery in Cook Inlet oil fields. About 80 percent of the energy content of the coal would be recovered in the syngas.
The Syngas will be used to power a 100 megawatt plant for the Alaska Railbelt power grid at Beluga. CIRI officials expect the plant to be online by 2014. This will be timely because power company officials were growing concerned that the amount of natural gas produced by oil wells in Cook Inlet was declining and would unable to meet power generating needs.
The project, which is expected to equal the production of 9 billion cubic feet of natural gas a year, is north of the Beluga River, in remote, generally uninhabited land, near the Chugach Electric Association’s Beluga gas-fired power plant on the Railbelt power grid. It’s also close to a pipeline system that ships natural gas to Anchorage.
If the Syngas project is successful, CIRI intends to expand operations to include synthetic gas production. The original process was discovered by German scientists Franz Fischer and Hans Tropsch in the 1920s (hence the name Fischer-Tropsch Process). They discovered that carbon monoxide and hydrogen (products of the UCG process) could be converted into liquid hydrocarbons through a chemical reaction. This synthetic liquid fuel is being certified by the United States Air Force for use in its air fleet.
CIRI has a lot of coal to fuel the operation. There is a 50 foot thick seam of coal 1,800 feet underground. Engineers calculate that the 100 megawatt plant will only use the coal under one square mile of land during its 30 year life. Given that CIRI has potential coal reserves on thousands of square miles, the potential for additional Syngas production is great.
The biggest problem is whether or not the Syngas can be economically produced. The first underground coal gasification project will cost about $30 million and the power plant $150 million. Then there is the cost of separating out the carbon dioxide and using it to produce additional petroleum from nearby oil fields. If natural gas prices drop too much in the current economic climate, the project could become uneconomical.
However, CIRI officials are confident that this project will reach completion. Ethan Schutt, the CIRI senior vice president for land and energy development noted that CIRI has world class coal reserves and this project is the key to commercializing them.
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