Last month, in Part One, we began a discussion about gypsum recycling coming to America. We saw how a Danish company, Gypsum Recycling International (GRI), has revolutionized the gypsum recycling industry and how, in Europe, the European Union has mandated stricter landfill regulations making gypsum recycling much more practical and economical than in the past. This month, we’ll conclude with a look at the technology that GRI and its American subsidiary, GRA (Gypsum Recycling America), is employing and its impacts on the domestic drywall construction industries.


There are three sources for the raw material gypsum – Calcium Sulfate DiHydrate (CaSO4*2H2O) – used in gypsum board panel production:

• Mined (Natural Gypsum)

• Synthetic (FGD Process)

• Recycled (Mill and Installation Waste)

Both synthetic and recycled gypsum are considered “recycled” gypsum. However, synthetic gypsum produced via the Flu Gas Desulfurization (FGD) process (see past article “Gypsum Synthesis”) is considered “pre-consumer” recycled material. The FGD process combines elemental calcium (from crushed limestone) and water with the sulfur oxides present in high sulfur content coal-burning power plants to produce synthetic gypsum, the purest form of gypsum at less than half the cost of mined and/or natural gypsum. By removing the sulfur from the smokestack’s effluent, most sulfur emissions into the atmosphere are eliminated. Mandated by the federal Clean Air & Water Act, the FGD process supplies the gypsum industry with a dependable, cheap and high-quality source of raw material and has simultaneously helped to mitigate the problem of acid rain caused primarily by sulfur oxides present in the Earth’s atmosphere.

Only recycled gypsum made from the mill-waste of the gypsum board manufacturing process and construction and demolition waste is considered “post-consumer” recycled material. In fact, almost all recycled content gypsum board made in the United States contains very little of this post-consumer variety; it is almost all synthetic gypsum or pre-consumer recycled content, but that is about to change. Gypsum Recycling America is bringing gypsum recycling to America in a very neat, compact package.

True GRT

GRA’s Gypsum Recycling Technology is a mobile, self-contained machine that consumes gypsum board scraps at one end and excretes a very pure gypsum powder and paper fragments at the other end. By being mobile – it can be placed on three or four trailers – the need to replicate the recycling machinery at each warehouse location is eliminated. The machinery simply moves from warehouse to warehouse as needed. In Scandinavia, a single GRT machine services Denmark, Norway and Sweden.

Helping Hand

To help get GRA off to a good start on this side of the pond, both U.S. Gypsum and National Gypsum have committed to purchase the recycled gypsum produced by GRA, adding up to 25 percent post-consumer recycled content in their manufacturing process for gypsum board. Though not expecting to realize profits for several years, USG is nonetheless assisting GRA with their initial operations here in the U.S.

As mentioned previously, gypsum board represents fully 1 percent of the entire solid waste stream presently. That’s not surprising considering the fact that gypsum board is the most widely used building material in the world. According to the Construction Materials Recycling Association, gypsum board is, perhaps, the most difficult C&D waste material to recycle. Known as “The Monster,” the GRT arrived in July 2006 at GRA’s main warehouse in Cambridge, Mass. Three other locations in Massachusetts will be set-up eventually, but initially, the Cambridge warehouse and another warehouse on Cape Cod (Holbrook, Mass.) will accept only virgin (non-demolition) waste gypsum board. Capable of processing both virgin and demolition waste when fully operational, GRA expects to accept demolition waste at all locations by the end of 2007.

Since the system is mobile, the distance the waste gypsum has to be transported is greatly reduced, thus making it more competitive with landfills. Being the only system capable of dealing with “old” gypsum waste that may contain nails, screws, wall coverings or other impurities, it has attracted not only the attention of USG and National Gypsum but other industry players including Lafarge, Armstrong and, of course, Denmark-based Knauf and CertainTeed (formerly BPB). With the technology making all gypsum waste 100 percent recyclable, the gypsum powder, representing plus or minus 94 percent of the waste, will close the loop of the manufacturing/recycling process while the paper (plus or minus 6 percent) will be used for a variety of things such as:

• Building Materials

• Composting

• Heat Generation

The Technology

Gypsum recycling is not a new idea. It has been around for quite a while, but not until recently has the process been perfected. Many gypsum companies tried to process gypsum waste from their manufacturing processes (mill waste) with dismal results. Typically, only 5 percent of the net product of their recycling process could be used in the mix with virgin gypsum powder. They had difficulty separating the gypsum powder from the paper faces and edges. No manufacturer or, for that matter, any gypsum recycler was ever able to process demolition waste.

Natural gypsum, or calcium sulfate dihydrate, is found worldwide, but the main producers via open-pit mining operations are the United States, Mexico, Thailand, Canada and Spain. With high oil and gas prices ongoing into the foreseeable future, power plants producing synthetic gypsum via the FGD process have been affected. This is all the more reason to consider the introduction of recycled gypsum. The GRT system includes:

• Collection System/Containers

• Logistics System

• Compact Mobile Recycling Unit

By taking waste from its place of generation to a process facility, the waste is economically and efficiently transformed into a usable raw material and delivered in a timely manner to a nearby production plant.

Win-Win Situation

By eliminating waste destined for landfills, the Earth’s resources are being conserved while mitigating the effects of hydrogen sulfide gas produced by waste gypsum. GRA has dedicated itself to being an “open system,” whereby all gypsum waste in a designated area, regardless of the original manufacturer, will be accepted. This openness has worked well in the European Union generating high gypsum recycling rates (65 percent in Denmark) by creating a non-competitive environment for gypsum recycling whereby all parties may benefit – not least of all mother earth.

Check out GRA for yourself