Washington, D.C.— The success of a U.S. Department of Energy (DOE) Clean Coal Power Initiative (CCPI) project has led to a repayment of $580,000 to U.S. taxpayers, with much more – potentially exceeding $13 million – possible in the future.
Great River Energy (GRE) of Maple Grove, Minn., made the payment to the Office of Fossil Energy’s National Energy Technology Laboratory (NETL) recently as part of an agreement associated with the DryFining™ CCPI project. Implemented by NETL, CCPI is a cost-shared collaboration between the Federal government and private industry aimed at stimulating investment in low-emission coal-based power generation technologies through successful commercial demonstrations.
The repayment is the result of two components in the agreement: (1) operational, paid upon use of the DryFining technology at the Coal Creek Power Station in Underwood, N.D., where it was tested; and (2) licensing, which depends on application of the technology in power plants outside of GRE. If the technology reaches its repayment potential, it has the possibility of delivering the largest return of any currently completed CCPI project for the research and development (R&D) investment made by taxpayers.
DryFining is a fuel enhancement system that uses a plant’s waste heat and a proprietary fluidized-bed drying process to remove moisture and impurities from low-rank coals, such as lignite, making their use cleaner and more efficient. It segregates particles by density, allowing a significant amount of higher density compounds, containing pollutants, to be removed rather than oxidized in the boiler.
As a result, sulfur dioxide and mercury are reduced by 40 percent, nitrogen oxide by 20 percent, and carbon dioxide by 4 percent. Removal of moisture prior to combustion decreases the volume of flue gas by 17 percent and improves the efficiency of fans, motors, and existing emissions-control equipment.
GRE initially tested a 115-ton prototype dryer at the 546-megawatt Coal Creek Station Unit 2. Following a successful increase in boiler efficiency and reduction of emissions, GRE expanded the project, using funding from DOE to consruct a full-scale dryer module for demonstration in Unit 2, and installing a full-scale dryer module for Unit 1 at their own expense. Ultimately the DryFining process improved the overall performance of the Coal Creek Station by almost 4 percent.
GRE said DryFining has a lower initial cost of installation and reduces expenses by more than $20 million annually. The financial and operational advantages of the technology for the Coal Creek Station, in comparison to alternative emissions control equipment, could eventually be seen in similar plants.
DryFining promotes the use of the nation’s vast resources of lignite—a low-rank, high-moisture coal—for power production. According to the Energy Information Administration (EIA), lignite accounts for about 9 percent of demonstrated U.S. coal reserves, and is located primarily in Montana, Texas and North Dakota. Since nearly one-third of U.S. electricity generation comes from plants burning high-moisture coal, the success of the technology has important implications for the nation’s energy supply and security.
DryFining received Power Engineering magazine’s prestigious Coal-Fired Project of the Year award in 2010. In addition to NETL and GRE, other team members on the DryFining project are Lehigh University, WorleyParsons, Heyl & Patterson, and the Electric Power Research Institute (EPRI).