Construction and demolition debris buried at the Collier County Landfill, Naples, FL, for 15 to 18 years has been reclaimed and successfully recycled in a mining/recycling test.
Modern Recycling Inc. of Florida conducted the test to determine the feasibility of landfill mining.
Of nearly 919 tons of construction and demolition (C&D) debris reclaimed, more than 78% (721 tons) was recycled. Only about 198 tons had to be returned to the landfill as waste.
After the tires and electrical wire (2.5 tons total) were removed, the remaining mined material was processed through a Grasan-designed recycling system. The system featured a horizontal-shaft impact crusher designed specifically for C&D recycling. Also comprising the system were an electromagnetic separator for removing ferrous metals, a specially-designed screen, an air sorting tower (for separating aggregates and wood), and radial stackers for conveying to storage piles.
The system produced fines for use as landfill cover and aggregates for building roads. It also yielded concrete-free rebar, dowel pins, and wire mesh ready for sale to metals recyclers.
"We didn't make use of reclaimed wood, as we do when we recycle incoming new C&D debris," said Brent Minet, project operations manager for Modern. "If we had, we would have returned less than 7% of the mined materials to the landfill as waste. Normally we sell recycled wood as fuel for power plants.
"The Grasan system is efficient, durable, and well engineered for our landfill recycling operation. We're … happy."
Contact: Grasan, 440 S. Illinois Ave., Mansfield, OH 44907-1809. Tel: 419-526-4440; Fax: 419-524-2176.