AER installed a scrubber on its Duck Creek Power Plant, near Canton, Illinois, and a scrubber on Unit 1 of Coffeen Plant, near Coffeen, Illinois. Reducing sulfur dioxide emissions by over 90%, the scrubbers are designed to redirect the outlet stack gas through a spray-tower scrubber design where the gas mixes with water, a 20% limestone mixture and compressed air.
The sulfur dioxide in the flue gas then reacts with the limestone to produce a gypsum by-product that can either be sold for commercial use or placed into a landfill for disposal.
The company will be completing the installation of another scrubber and electrostatic precipitator within the first quarter of 2010 on Unit 2 of the Coffeen Plant.
In 2009, a new precipitator was also installed at the Duck Creek Plant. Electrostatic precipitators offer an efficient way to capture particulates before they go into the atmosphere.
To further reduce mercury emissions, AER has also installed activated carbon injection systems at the E.D. Edwards Plant, at its Meredosia Plant near Jacksonville, Illinois, at Newton Plant, in Jasper County, Illinois and at the Joppa (Illinois) Power Plant (an Electric Energy plant that is 80% owned by Ameren).
With activated carbon injection systems, powdered activated carbon absorbs the oxidized mercury from the flue gas, and the mercury is then collected with the fly ash in the plant’s particulate collection device.
These initiatives follow the installation of a range of combustion control technologies, like low-nitrogen oxide (NOx) burners that reduce NOx emissions at many of the Illinois plants.
