Wallboard Goes Green as Firms Recycle Gypsum

Wallboard Goes Green as Firms Recycle Gypsum

   Gypsum wallboard — the ubiquitous material found in homes, offices and other buildings — is finding new life when recycled as a soil additive, especially for farm crops.

   Rather than seeing wallboard being dumped in landfills, companies such as Quality Soil Amendments (QSA) in California and Agri Marketing, Inc., in Pennsylvania have built successful businesses recycling drywall, then reselling the pulverized gypsum.

   “Doing what we’re doing, whether it’s me doing it or somebody else, is the right thing to do and I believe it is sustainable now and in the future,” said Terry L. Weaver, president and general manager of Agri Marketing based in Reinholds, Pa.

   Both Agri Marketing, with plants in Reinholds and Turbotville, Pa.,  and Quality Soil Amendments based in Bakersfield, Calif., take in new construction scrap drywall from building projects and recycle the material. Each company annually ships about 20,000 tons of gypsum (calcium sulfate dihydrate). 

    There’s no shortage of new drywall, with the U.S. producing approximately 15 tons of the material a year, according to the California Integrated Waste Management Board. California, alone, uses an estimated 1.8 million tons, it said. 

   “Approximately 12 percent of new construction drywall is wasted during installation,” the board said. “Therefore, over 200,000 tons of new drywall scrap may be generated in California per year. The amount fluctuates with the construction industry, and with natural disasters such as floods and earthquakes.”

   Justin Karr, who founded QSA, pointed to statistics showing that for new construction, one pound of scrap was generated per square foot of material used. The vast majority of drywall waste — 64 percent — is from new construction, according to studies.

   “The construction of an average single-family American home (2,000 square feet) generates nearly one ton of new, uncontaminated drywall waste,” reported the Waste Management Division of the Vermont Agency of Natural Resources. “As a result, construction, like that of new homes and commercial building, is responsible for approximately 64 percent of drywall waste; the remaining drywall waste originates from manufacturing, renovation and demolition.”

   Despite the U.S. economy being in free-fall – with government reports showing housing starts in December falling more than 14 percent to the lowest point in more than 16 years and building permits dropping to levels not seen since early 1993 — Karr reported his recycling business was booming.

   “We get more coming in every day than we have time to process now since we’re growing so much,” he said, adding that he has had requests to start up a similar recycling business in Arizona.

   He said QSA receives five to six truckloads of material daily.

   Weaver said his business held steady in late 2008 and that the 20,000 tons of material it handled during the year was a tiny fraction of total drywall scrap being recycled in his area. Having completed one plant expansion in 2006, he said his company could handle a “significantly larger quantity” of drywall.

   “We can easily double the volume we’re handling,” Weaver said. “We believe that we have the markets positioned to not only be able to take it in and process it but to market it.”

   Recycling gypsum is not new. In addition to being used as a soil amendment, it can be used as an ingredient in making such things as cement, compost and in production of new plasterboard. At Agri Marketing, the paper backing on the wallboard is also recycled and sold as animal bedding. As a soil amendment, gypsum usage ranges from general agriculture to residential lawns and golf courses.

   “The purity and quantity of gypsum present in drywall provides a number of opportunities for economically and environmentally feasible recycling and reuse,” Vermont officials said.

   “Recently there has been increasing interest in recycling gypsum wallboard by crushing and sieving scrap material and applying it to crops or on-site at the construction location,” said Richard P. Wolkowski, a soil scientist at the University of Wisconsin-Madison, in his report, Using Recycled Wallboard for Crop Production. “Land application of this material could offer a win-win solution for both the creators and the users of this construction debris because of reduced disposal costs and potential agronomic benefits.”

   Recycling the wallboard keeps it out of landfills — where it can cause  environmental problems with sulfates contaminating groundwater and hydrogen sulfide gas being released into the atmosphere at toxic levels — while preventing the depletion of gypsum as a natural resource. Shipping mined gypsum, much of which is brought into the Northeast from Canada, also requires huge amounts of energy to transport both by sea and then by land, Weaver said.

   As a soil additive, recycled gypsum benefits farmers and other growers and, Weaver noted, it can be purchased at a substantial savings over similar commercial products.

   “Gypsum provides a source of calcium and sulfur for plants . . . Many vegetables, including potatoes and corn, have been shown to benefit from gypsum application,” the Construction Materials Recycling Association reported.

   A study conducted in 2006 on the use of recycled gypsum on a farm in England found that “the overall quality of the potatoes grown with recycled gypsum was higher than those in the untreated soil . . . The farmer involved in the trial was convinced of the benefits of recycled gypsum and intends to continue its use on his fields when required.”

   Tests conducted in various states in the U.S. have had mixed results. In Wisconsin, a two-year study in 1997 and 1998 on sites growing potatoes found the addition of the crushed wallboard or commercial gypsum fertilizer “did not significantly affect potato yield.” In New York, the addition of gypsum to highly acidic soil growing corn resulted in a 25 percent positive yield, the same as achieved with agricultural gypsum or lime.

   “Unlike lime, gypsum does not raise the pH of soils and it is thus preferred for crops that require calcium but where the soils are already alkaline and cannot accommodate pH adjustment,” noted the Construction Materials Recycling Association. “Gypsum has also been found to be useful for reclaiming very salty soils; the calcium in the gypsum substitutes for the sodium in the soils, allowing the sodium to leach away. Gypsum has the ability to flocculate clay soils that have drainage problems.”

   Karr, who launched his business in October 2000, and Weaver, who started Agri Marketing two years earlier, readily agree that gypsum helps improve soil conditions in a variety of ways, from helping plants absorb nutrients to stopping water runoff and erosion.

   “When you have heavy clay soil, you have salts in the soil, so the soil is locked up,” Karr explained. “Water just goes straight across the soil. But when you add the calcium sulfate to the soil from the gypsum, it takes those salts and swells them up and opens up the soil so you get water penetration.”

   Karr initially worked for a Bakersfield company that also recycled wallboard before deciding to launch his own business. He has a background in agronomy.

   “There really isn’t any magic to it,” he said. “We just crush up the wallboard and extract the gypsum.”

   Initially, QSA took in the drywall debris, pulled out the contaminants and crushed it with a dozer and screened it in a trommel. QSA pays for the scrap wallboard, which Karr said helps offset the trucking costs borne by the construction companies shipping the material to his facility.

   After sorting through the construction debris brought to QSA from California and Arizona and pulling out metal, paper and plastic — all of which he says ends up being recycled — the drywall is loaded into a high-speed grinder where it is pulverized. The paper backing on the wallboard is also pulverized in the process.

    “The paper gets ground up and we’re seeing organic levels coming up because of the wood fiber from the paper,” Karr reported.

   Karr sells the crushed gypsum to farmers, stretching to the California-Oregon border, who grow crops including almonds, carrots and grapes. Additional soil amendments are rarely added to the gypsum, he said.

   “It depends on the soil analysis,” Karr said. “All our work is done off a soil analysis. We don’t do anything without it.”

   That soil analysis provides details on everything from calcium levels to the iron, copper, zinc and sulfur in the soil.

   “Nine times out of 10 we’re just delivering straight gyp,” he said.

   QSA has a staff of four plus Karr and is housed on a 50-acre industrial site. Four other companies lease space on the site. Karr said he is looking ahead to adding customized equipment to streamline and improve the process of sifting the materials.

   He also is looking at expanding his services, which could involve processing sulfur as a soil amendment and lumber for a sawdust application. While not revealing details of the lumber plan, he indicated it would have something to do with using sawdust as a replacement material in an existing application.

   Agri Marketing, which sells its recycled gypsum under the USA Gypsum label, offers different methods of collecting drywall, including placing dedicated roll-off containers at construction sites or cleaning the job site after the drywall contractor’s job is complete. Unlike QSA, it does not pay contractors for the scrap drywall. 

   Agri Marketing services and sells its products throughout a triangular geographic area from New York City in the northeast to Pittsburgh in the west to Washington, DC, in the southeast.

   Drywall that is brought to Agri Marketing is processed in a pulverizer, which produces three waste streams: a fine pulverized gypsum, a coarse granular gypsum and the paper facing which is used for animal bedding. A proprietary secondary process produces an ultra-fine gypsum. The recycled gypsum is sold in bulk tractor-trailer loads, in one-ton Super Sacks and in 40- or 50-pound bags which can be purchased in hardware and garden supply stores as well as ordered directly online (www.usagypsum.com).

   Agri Marketing sells pure gypsum; it does not do any soil analysis for customers, leaving to others that task and the addition of any amendments that may be needed to meet specific soil conditions.

   The company has a staff of eight, as well as six dedicated subcontractors. Its 16,000-square-foot Reinholds plant has a monthly capacity of 1,500 tons; the 14,000-square-foot Turbotville plant and can handle 3,200 tons per month.

   Even though Karr is helping divert drywall material from landfills — with other applications to possibly follow — he said he doesn’t really consider himself an environmentalist.

   “I brought it (drywall) in because the landfills didn’t want it for health and environmental reasons,” he said.   Weaver, however, said he views Agri Marketing as more than just a business.

   “I like the term sustainable business,” he said. “I believe that conserving the earth’s resources and being a steward of those resources is a very important issue. . . I want to feel good about what I’m doing, feel like I’m making a difference and feel like I’m making a difference not just for me here and now but for future generations.”