Boswell Energy Center Unit 4

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Boswell Energy Center Unit 4 (Boswell 4) is a 585 MW sub-bituminous coal-fired steam electric generating unit that was placed into service in 1980.  It is located at the Boswell Energy Center in Itasca County, near Grand Rapids, Minnesota.  Based on WPPI’s undivided 20% ownership share in Boswell 4, WPPI’s capacity from Boswell 4 is approximately 117 MW. 

Boswell Unit 4 employs a selective non-catalytic reduction system (“SNCR”), low NOX burners and a Separated OverFire Air (“SOFA”) technology for NOX emissions controls.

In 2015, an environmental retrofit project at Boswell 4 was completed as a multi-pollutant solution for reducing mercury, particulate matter, sulphur dioxide and other hazardous air pollutants consisting of a Circulating Dry Scrubber system incorporating a fabric filter (bag house), and  a powdered activated carbon injection system to control mercury emissions.