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Mecklenburg County’s Unpainted Gypsum Board (Drywall) Recycling Program

Mecklenburg County’s Unpainted Gypsum Board (Drywall) Recycling Program. Michael Talbert Mecklenburg County Solid Waste Dept. What is unpainted gypsum board?.

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Mecklenburg County’s Unpainted Gypsum Board (Drywall) Recycling Program

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  1. Mecklenburg County’s Unpainted Gypsum Board (Drywall) Recycling Program Michael Talbert Mecklenburg County Solid Waste Dept.

  2. What is unpainted gypsum board? • a family of panel products that consist of a noncombustible core, composed primarily of gypsum, and a paper surfacing on the face, back and long edges. It is used to make interior walls and ceilings. • Gypsum board is also known as drywall, plasterboard, and wallboard. Note: Sheetrock is a trademark brand name of drywall • Gypsum = calcium sulfate dihydrate, CaSO4·2H2O

  3. Why Recycle Gypsum Board? • Save landfill space • Reduce hydrogen sulfide gases • Positive public information story that encourages building community to recycle

  4. Mecklenburg County’s Program • Have been recycling gypsum since 2008 • We offer a $10/ton reduced tipping fee for clean drywall from new construction (no painted drywall or material from demolition. • We were paying $20/ton for a company to pick it up and process it for sale to a fertilizer market • Beginning Summer 2014, that market couldn’t keep up with supply of material

  5. 2014 2016

  6. Gypsum Agricultural Applications • One of the earliest forms of fertilizer used in the US. It has been used in agriculture for more than 250 years. • Agricultural Crops • Nursery, Greenhouse, Landscape, and Sports Field Use

  7. Gypsum Agricultural Benefit Findings • Adds calcium and sulfur • Increases crop yields • Remediates sodium-affected soils • More soluble than lime • Doesn’t need to be tilled to provide calcium and sulfur to grasses. • Ameliorates aluminum toxicity from high nitrogen fertilizer applications • Improves deep rooting, water and nutrient uptake • At 2 tons/acre – most effective and cost efficient way to reduce phosphorus in surface water runoff • improves surface infiltration • Reduces soil erosion

  8. Sources of Gypsum for Agricultural Use • Synthetic Gypsum: Coal-fired power plants – Flue Gas Desulfurization (FGD) • Mined Gypsum • Gypsum Board (Drywall)

  9. Steps We Took To Develop a Market for Drywall • Contacted Agricultural Extension Agents in Mecklenburg and surrounding counties. • Found a farmer that was using a significant amount of gypsum. • Approached the farmer to see if they were interested in substituting some of their purchased gypsum with our gypsum board (drywall). • Worked with farmer to obtain relevant approvals

  10. Submit crushed drywall sample to NCDA for a Waste Report (not a soil sample report)

  11. In NC, Farmer applies to State Ag. for permission to land apply drywall material as a nutrient source • Description of material • Method of land application • Specific benefit to be derived from the land application • Best Management Practices to be used for land application • Best Management Practices to be used for storage

  12. Application rate and diversion potential • Can be applied at a rate of between ½ - 4 tons per acre depending on the soil analysis and crops planted. • NCDA has established a load limit of 5 tons/acre for our farmer with our material. • Farmer we are working with currently buys about 30,000 tons per year. • About 4-5 times what we are currently collecting at our landfill annually • Not applied between mid-April and August

  13. The Operational Challenge Our drywall What the farmer was buying

  14. First we tried crushing with landfill compactor

  15. Getting Better Our uncrushed drywall Our crushed drywall

  16. But more work was needed Our crushed drywall What the farmer is buying

  17. Equipment demo in fair weather determined a processing path forward...

  18. And then it rained…a lot

  19. Ground Material – ready for shipment

  20. 2016-17 Drywall Recycling Metrics

  21. 2016-17 Drywall Recycling Costs

  22. Bonus Slide – according to the Gypsum Association, Gypsum can also be used: • As an additive in turbid water, particularly ponds, to settle dirt and clay particles without injuring aquatic life. • To create surgical and orthopedic casts. • As a food additive. Gypsum (calcium sulfate) is recognized as acceptable for human consumption by the U.S. Food and Drug Administration for use as a dietary source of calcium, to condition water used in brewing beer, to control the tartness and clarity of wine, and as an ingredient in canned vegetables, flour, white bread, ice cream, blue cheese, and other foods. • As a color additive for drugs and cosmetics. • A primary ingredient in toothpaste. • Gypsum also has played an important role in the entertainment industry. Historically, before the era of computers and high-tech special effects, film and television producers would drop “showers” of gypsum in front of the cameras to simulate snow storms.

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