Mercury Control Technologies
The scrubbers and selective catalytic reduction technologies that Duke Energy is installing on many of its coal-fired power generating units to control sulfur dioxide (SO2) and nitrogen oxide (NOx) emissions have a co-benefit of removing a significant amount of mercury. While we’re still in the process of understanding how much mercury will be removed by these control devices on a consistent basis, we currently estimate reductions in mercury from these devices to be between 60 percent and 80 percent.
Research is being done by government and industry to further develop mercury control and measurement technologies. Duke Energy is contributing to that research in the following ways.
- In 2003, 2004 and 2005, Duke Energy partnered with the U.S. Department of Energy to test the performance of impregnated carbon injection on a hot-side electrostatic precipitator at the Cliffside and Buck steam stations.
- In 2004, Duke Energy tested the mercury removal capability of a pilot wet limestone scrubber at the Marshall Steam Station.
- In 2004, Duke Energy worked with the Electric Power Research Institute to test the performance of impregnated carbon injection on a cold-side electrostatic precipitator at Allen Steam Station.
- Duke Energy funded a mercury monitor study to review existing monitors on the market to determine what changes/improvements should be made to improve their performance. Duke Energy has also purchased and is testing the performance of two types of mercury continuous emissions monitors.
- In early 2006, Duke Energy hosted a research project at the Miami Fort Generating Station to demonstrate the performance of sorbent injection for mercury control. The demonstration included the use of Amended Silicates™ sorbent and Norit’s Darco HG powdered activated carbon (PAC). The demonstration was funded in part by the U.S. Department of Energy’s National Energy Technology Laboratory.