The project at Coffeen station is part of a $1bn environmental improvement program conducted at AER’s coal-fired power plants in Illinois. The Coffeen project called for Alberici to construct a new scrubber facility to remove sulfur dioxide from combustion gases coming from the plant’s two coal-fired boilers.
To construct the facility, Alberici installed two large absorber vessels and related equipment manufactured by Hitachi Power Systems America. The facility grinds limestone, adding it to water to create a slurry that is then sprayed over the combustion gases in a large absorber vessel.
This chemical reaction extracts sulfur from the gases and converts the limestone slurry to gypsum – a potentially useful by-product. Alberici worked with AER’s engineering firm, Sargent & Lundy, to perform the design-build project.
In addition to the sulfur dioxide scrubber system, the project called for Alberici to construct a new electrostatic precipitator system, which uses electric charges to remove particulate matter from the plant’s combustion gases.
