Monday, December 1, 2008

Drywall...with a conscience

A colleague of mine at Philadelphia University recently told me about a new drywall plant in PA that is actually built right next to a coal-fired power plant in order to readily capture the synthetic gypsum byproduct for use in their drywall. I am looking into sourcing all our drywall from this plant.

United States Gypsum Corporation
Lycoming Mall Dr
Washingtonville, PA 17754
(About 2.5 hours from Philadelphia)

The facility produces wallboard using recaptured gypsum, uses 100 percent recycled paper for the surfaces of the finished wallboard products, recycles 100 percent of its production waste and feature a closed-loop liquid effluent system, which translates to zero discharge into nearby waterways. It was purposefully located right across the road form the Montour (coal-fired) Power Plant. At the power plant, scrubbers (the environmental controls that remove the sulfur dioxide from the emissions of coal-fired power plants) work by spraying a mixture of crushed limestone and water onto the exhaust gas before it goes out the plant’s chimney. The limestone and water react with the sulfur in the plant’s exhaust to form synthetic gypsum, which is collected and shipped to the USG facility that is across the road from the power plant.

OR...if that doesn't pan out

Green Depot actually stocks drywall that contains 95% recycled coal ash that they get from another Pennsylvania drywall plant (also USG, I believe) that employs the same process as the Washingtonville plant, it's just not right across the street from the power plant.

The price per sheet is virtually the same as any other drywall. We are going to look into both options but seeing that we need have drywall on site in two looks like we might be giving Green Depot a call. It's nice to know they're close by.


Anonymous said...

What's the pollution factor? Is the byproduct safe to use? Is the power plant contaminating the byproduct?

Southern Liberties, LLC said...

It is my understanding that the "scrubbing process" separates the harmful byproducts (carbon dioxide and nitrogen oxide...which go to the stacks and get filtered) from the sulfur portion of the coal exhaust by adding in the dampened limestone element (or other sorbent). The calcium slurry reacts with the sulfur and forms hydrous calcium sulfate (or gypsum). Synthetic gypsum meets all the purity standards that natural gypsum (which you could basically eat if you so desired) meets.

(ref. USGS Fact Sheet 076-01)