Around the country, dozens of coal-fired power plants are racing to install pollution controls to comply with new mercury rules from the Environmental Protection Agency. But how do they keep 100,000 tons of coal-fired pollution out of the air? Install thousands of air filters.
Todd Kollross is managing the $750-million project at the Homer City Generating Station in Indiana County, Pennsylvania. Inside the new unit, he shows off what look like hundreds of holes in the floor. Each is lined with a filter bag. They’re basically super-sized Shop Vac filters.
Here’s how it works: Coal exhaust coming out of the boilers at the plant is sprayed with a powder. The powder absorbs the pollution and particulates in the exhaust, and the filters — or bags — catch the powder.
“You got 40,000 [bags] between the two units,” Kollross said. “All the particulate that we collect from the flu gas comes into these bags.”
And that pollution goes into the landfill, instead of residents' lungs.
One small problem: Those filters don’t take out carbon dioxide, the main culprit in global warming. And the EPA plans to limit carbon dioxide emissions from coal plants.
Just in case, Homer City is applying for permission to start burning natural gas, which produces half the carbon emissions of coal.
Read more of this and other stories at the website of our partner The Allegheny Front.
