The Orrington, Maine-based Penobscot Energy Recovery Company (PERC), which turns municipal and commercial waste into renewable power, recently held a ribbon cutting for a new multi-million dollar waste processing system that the company says will streamline the waste-to-energy plant’s operations, using less energy and helping recover more metals for recycling.
“This new system represents an important evolutionary change in the way we process waste,” says Plant Manager Henry Lang in a news release. “It allows us to utilize nearly 100 percent of the waste we receive from municipalities and commercial waste haulers, recycling it into steam and electricity and reducing even further the amount that ends up in the landfill.”
The improvements are centered around a new conveyor line that screens and delivers processed waste to the plant’s boilers. It replaces two older lines that date back to the plant’s original construction and were expensive to maintain, PERC says.
The new process line works in combination with PERC’s recent acquisition of slow-speed grinders, called Terminators, from Komptech, with U.S. headquarters in Westminster, Colorado. PERC says the machines help create a more uniform fuel size, which makes combustion more efficient. If some of the waste is not properly sized, the new line sends it back to the Terminator for a second pass, enabling higher utilization of waste.
The Terminators also allow PERC to process oversized bulky waste (OBW), such as carpet, tires, wood waste and other materials that other waste facilities won’t take and previously went directly to landfill. Unlike the plant’s original stationary grinders, the Terminators are mobile and can be moved around the facility to allow easy maintenance and accommodate flexible processing modes.
In the last few years, PERC has a has purchased three Terminators and is planning to acquire a fourth soon.
The new processing line also uses much less electricity. Since PERC generates its own power, Lang says that means more of the plant’s output can be sold on the grid. In addition, PERC says a “sophisticated” new screen in its ash system allows the company to recover more metals from the ash that remains after the waste-derived fuel is burned. The metals are then sold to a recycler.
During the ribbon cutting, Lang lauded PERC’s owners for their continuing investment in the facility and their commitment to its future as a key part of Maine’s solid waste management system. He also praised PERC’s 55 employees, many of whom were directly involved in the design, construction and commissioning of the new processing system.
“Our team in second to none in terms of their ingenuity and commitment to environmental stewardship,” Lang says. “In addition to our employees, our strength has always been that our waste-to-energy technology works. These improvements will help us better serve our customers and operate more efficiently.”
The ceremony was attended by PERC’s owners, which include several of the more than 40 communities the plant serves, local and state officials and area business people.
PERC accepts waste through contracts with more than 40 Maine communities and a number of commercial haulers that serve area businesses.
After processing waste, PERC uses it as fuel to generate renewable electricity, reducing the volume of material that ends up in a landfill by 90 percent.