People were able to get their first look inside the Perham Resource Recovery Facility last week. An open house was held in light of expansion work starting to wrap up.
The recent expansion will increase annual processing from 35,000 tons of waste to more than 50,000 tons, according to a press release from Otter Tail County. It also includes the addition of a Materials Recovery Facility (MRF) to sort garbage before it enters the incinerator.
Garbage enters the facility on the “tipping floor,” where trucks dump out their load of trash. Essentially, any waste from the Perham area that is not recycled through pickup programs ends up here, explained Brian Schmidt, who has been the facility’s manager since 2003.
From the tipping floor, payloaders are used to scoop mounds of garbage into a conveyor belt feeder. The belt runs in to the MRF and through several picking stations.
At the picking stations, six workers wearing Kevlar gloves pull out recyclables, non-combustible materials and oversized items that could plug up the rest of the system. Some are sent to a bypass bin to be disposed of elsewhere, Schmidt said, while burnable items are sent directly to be burned. Recyclables are baled to be sold to brokers.
Intact garbage bags are not opened by the pickers. Instead, this is done by the next piece of equipment, a “trommel,” which is a hollow, rotating cylinder with sharp knives and holes of various sizes.
When the bags enter the trommel, they fall onto the knives and get torn open. As the now loose garbage is spun around, items fall through the holes to be sorted. First are smaller, 2-1/2 inch holes to eliminate dirt, batteries and broken glass. Next are holes that are 6-1/2 inches, which allow cans to get out of the stream.
Schmidt said VCR tapes and diapers make the most mess inside this piece of equipment. Once a week, he said, workers used to have to put PVC guards over the knives, then scrape and clean the trommel’s interior. Now, a newly-installed air cleaning system just blasts the equipment clean.
From the trommel, items either go through additional sorting or are burned.
Aluminum and tin cans, other metal items, electronics and more are separated out and sold to be recycled.
“It’s kind of discouraging, the amount of recyclables that come through here,” Schmidt said. “This is not a recycling facility. We just clean the garbage we’re going to burn.”
But selling the recyclables can be profitable.
“WE Fest was awesome for us,” Schmidt said, estimating that they collected 10 bales of aluminum cans, each weighing about 4,200 pounds, from the festival’s waste.
Where the facility earns some for its desirable recyclables, it also loses when TVs, computer monitors and other electronics come through.
“We still have to pay $10 to dispose of each of these,” said Schmidt.
Some heavy debris, called “fines,” such as dirt and rocks, are sent to the Clay County landfill. There, the fines are used as temporary cover to keep down pest activity.
After sorting is completed, the remaining garbage is taken out of the MRF via another conveyor, to be added to the burn pile.
A remote crane operator in the control room supplies the burn pits with fuel as needed. Other employees in the control center monitor the temperature, pressure and emission statistics of the plant’s burner and boiler units. On average, the temperature in the burners is between 1850 and 1900 degrees Fahrenheit.
Ash from the burners is treated and sent to the “bag house,” which is essentially a big vacuum cleaner to remove ash, explained Schmidt.
Since the MRF began operation, he said, ash output has decreased by almost 50 percent. This ash is the only thing that is actually hauled to the landfill.
The facility originally opened in 1986 and continuously operated until closing in July of 1998 because it could not meet air emission permit requirements. In December of the same year, the owners donated the property and facility to the city of Perham.
Once Perham and Otter Tail County owned the facility, a partnership was formed with Becker, Todd and Wadena counties and they began to apply for grant funding from the state to improve and reopen the business in 2002.
The Resource Recovery Facility is now officially run by the Prairie Lakes Municipal Solid Waste Authority, which is a joint powers group comprised of five counties (Clay joined on Sept. 1 of this year). Garbage from these counties is processed and the resulting steam is sold to Bongard’s Creamery and Tuffy’s Pet Foods.