A commingled solution
Romerike Avfallsforedling (RoAF) operates the world's first completely automated MRF.

A commingled solution

RoAF’s automated MRF in Norway offers an innovative way to separate recyclables, organics from waste stream.

August 14, 2019

The smell of the facility always comes as a shock, says Matthew Everhart, CEO of Stadler America, who has taken several people to tour the world’s first totally automated municipal solid waste (MSW), recycling and anaerobic digestion facility in Skedsmo, Norway, just outside of Oslo.

“Anyone that’s ever been to a landfill knows what waste smells like when there’re organics in it,” he says. “This plant doesn’t smell at all.”

The other thing they notice while touring the $234 million facility, operated by waste and recycling company Romerike Avfallsforedling (RoAF), is how clean the fiber looks.

“The thing you hear about mixed waste processing is that it’s hard to get good quality fiber out of it,” Everhart says. “Any recycler I’ve taken to this plant couldn’t believe how good the paper looks and the fact that it didn’t smell.”

That’s because, as part of a new recycling program, the Norwegian municipality developed a system where residents place their organics in bright green bags, which they then put in the recycling bin with other materials. The first step in the plant design is to remove the organics from the rest of the stream.

Norway has high labor costs, Everhart explains, which is one of the reasons why the municipality in 2016 decided to put out a bid for an automated facility. The plant has been fully operational since late 2017.

“Essentially, the cost of labor to recycle outweighed the value of recyclables,” Everhart says. “They put out a bid to all the major European players for a system that was fully automated with no manual labor sorting required because it made financial sense for them.”

He adds, the automated concept was “not only new for us, it was new for the world.”

Stadler Anlagenbau, Germany, was awarded the bid and constructed the facility in three months. The plant requires only two operating staff to load materials and remove baled materials.

“It has happened in stages,” Everhart says. “The plant was built in 2016. Within a year, they said, ‘this really works,’ and they did a big expansion to allow for future growth.”

Norway uses a three-bin collection system: one for organics; one for plastic, paper and cardboard; and a third bin for glass and aluminum cans. There is also a red bin for electronic scrap and household hazardous waste. The plant recovers 5,000 tons of recyclables per year. Of that, 2,500 tons are plastics, including polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP) and film grades.

When the organics arrive in the green bags at the plant, they are separated from the other materials as quickly as possible. The bright green color was chosen by the municipality because it’s easily recognized by the optical sorters. The plant features a combination of 16 near-infrared optical sorters by Norway-based Tomra and Stadler's mechanical sorting equipment, including drum screens, bag openers, ballistic separators, an eddy current, magnets, a vibrating screen and a shredder.

Material flows through screening separation first, then optical separation for bag removal and dimensional separation before being processed by specific material recovery systems for fiber, plastics, metal, glass and organics.

“The first thing we do is eject out the green bags the machines can recognize as separate,” Everhart says. “Then we start breaking down the material by particle size, dimension, then by density and then by polymer for the plastics and by its ability to absorb light.”

The technology and sorting process is common among material recovery facilities (MRFs) around the world; however, the municipality’s way of collecting organics in green bags in the same bin as other materials and the plant's design to remove paper, plastics and metals from the organics and residual waste for further recycling is what makes the facility different.

“The difference is rather than asking the consumer to do the first step in recycling, we’ve given them a way to separate them, but still put them all in one bin,” Everhart says.

He adds, “The real skill is our ability to know how to take our own equipment and integrate it with Tomra’s optical sorters. The system has a very advanced amount of technology to separate the organics material but also to get the fiber away as soon as possible so the material doesn’t absorb that odor.”