http://www.newsobserver.com/2010/03/11/381525/pmi-applauded-for-making-green.htmlAs the state and its utilities grapple with what to do with coal ash - the residue left when coal is burned to make electricity - a Cary company is quietly doing something about it.
PMI Ash Technologies pipes the residue, fly ash, out of the coal plants, extracts the residual energy and then produces a material that can be used to make concrete. That product is considered an ecofriendly building material because it reduces the amount of ash that is put in coal ash ponds and landfills.
"Concrete is like banana bread: Everyone has their own recipe," saysLisa Cooper, PMI's senior vice president. "Within concrete there is a binder called portland cement (like the eggs in your recipe). The fly ash can replace that binder."
Using ash in this way is popular with environmental groups because it reduces the amount of ash that can leach into groundwater. Concrete makers like it because it's durable and less expensive than portland cement.