USA . COAL FIRING
US Energy Secretary Spencer Abraham has announced the test site for the ‘lignite fuel enhancement’ system, a new process that reduces emissions, while boosting overall generating capacity, by using waste heat to dry high moisture content lignite fuel prior to combustion.
Secretary Abraham commented “This project demonstrates that environmental protection and energy production are not competing priorities. With advanced clean-coal technologies, we can enjoy clear skies while maximising our use of our most abundant domestic energy resource.”
The Great River Energy project is one of eight selected in the initial phase of president Bush’s Clean Coal Power Initiative, a 10-year, $2 billion commitment and a key component of the national energy policy. The programme seeks commercial-scale technology demonstrations on a competitive basis to continue and expand the use of coal as a fuel source.
Great River Energy and its research partners will conduct the project at it’s Coal Creek Station in Underwood, North Dakota. The $25.6 million project will administered by the energy department’s Office of Fossil Energy, and managed by the National Energy Technology Laboratory. The Energy Department is expected to provide $11 million for the project over its 45 month duration.
In the project’s first phase, a prototype module will be designed to dry about one-sixth of the coal fed to a 546 MW unit at the Coal Creek Station. Following successful demonstration of the prototype Great River Energy will design, construct, and perform full-scale, long-term operational testing on a complete set of dryer modules needed for full power operation of one of the 546-MW units.
The researchers will use North Dakota lignite, which typically contains about 40% moisture. They expect to lower this figure by at least 10 percentage points, resulting in an estimated 2.8 to 5% efficiency gain in the plant. This translates into 25% less emission of SO2, and 7 % lower emissions of mercury, CO2, NOx and particulates per unit of output.
Successful commercial application of the technology could result in striking benefits nationwide. In the US today, 35 power generation units, with an installed capacity of 15 GW, burn lignite; 250 units, with an installed capacity of about 100 GW, burn Powder River Basin coal, a subbituminous coal with a high moisture content. Over the next two decades, the capacity of power plants burning high-moisture coals is projected to increase by another 100 GW.
•The viability of lignite firing in Europe is heavily dependent on its status under carbon emission National Allocation Plans, which were due to be discussed by the EC in mid-July. German utility RWE has embarked on the approval process for a new lignite plant, BOA2, at Neurath, to be constructed by 2010. The decision to build will taken by end-2004, and will depend largely on the final NAP due in summer 2004. Meanwhile Vattenfall Europe AG of Berlin has announced that it intends to build a new lignite powered plant in Saxony and a new hard coal power plant in Hamburg. Sites for these projects have already been licenced, but again, the significant level of investment required for these projects would have to be considered in the light of the NAP CO2 allowances.