Composting is getting high-tech in Ramsey and Washington counties.
Residents of four cities there can now throw compost in the trash — and let artificial intelligence sort it out. Something like.
With the county’s new food scraps collection program, special bags of compost can be tossed into trash carts, where they are picked up by vehicles, transported to the county’s waste facility and sorted using artificial intelligence and robotics hands that can pick them.
If this all sounds different from other curbside compost programs, it is.
“We’re probably one of the first communities of this size program to do it this way,” said Sam Hall, facility manager of the Ramsey/Washington Recycling & Energy Center.
A pilot program expanded in October to all residents of Maplewood, North St. Paul, Cottage Grove and Newport. It is expected to eventually be available to all Ramsey and Washington County residents.
Artificial intelligence and robots
Conveyor belts carry the trash to a small room at the Newport Recycling and Energy Center, the facility where Ramsey and Washington County residents’ trash goes. There, a machine that connects to the belt scans the trash as it moves through it at 73 feet per minute, using artificial intelligence to identify bags of food scraps based on their color and size.
These food waste bags are not your ordinary compost bags. They are specially designed to withstand the ride of the garbage truck and the conveyor belt.
When the AI machine finds one, it tells a robotic arm just down the line where the bag is. With a quick, precise movement, the arm swings and grabs it, separating the bag of food scraps from the kitchen trash bags, expired Halloween pumpkins, and other junk.
At least that’s what happens most of the time. Sometimes the AI misfires, sending the robotic arm to grab a bag that looks like a bag from the food scraps program, but isn’t.
The technology is already used to identify aluminum cans, but using it to retrieve bags of leftover food is new, said Joe Heinz, the facility’s maintenance manager.
Workers at the facility train the equipment: Anything identified as a bag of food scraps — correctly or incorrectly — is fed through the machine again so it can be told whether it guessed correctly or not.
For now, food scraps are sent to a commercial composter. Eventually, they will be sent for anaerobic digestion to generate energy, Hall said.
In Minneapolis and many other communities, residents can order a compost cart that is collected separately from trash.
In Ramsey and Washington counties, residents have been waiting longer for curbside composting, but the benefits of the so-called “co-collection” model, where trash bags and food scraps are collected together, are many, said Annalie Garletz, program food waste recycling manager.
On the one hand, it is easy for residents and waste haulers because it does not change the disposal structure. Second, it is available to renters and homeowners at no additional cost beyond what they already pay for garbage. Counties cover the cost of the bags, which range from $23 to $32 depending on size, and mail them to participants.
Third, “it leads to less greenhouse gas emissions because there are fewer trucks,” Garletz said. “There is no separate compost pickup truck that has to travel down the road and then to the facility.”
With the launch in four cities since last month, the program is available to 40,000 households. As of Monday, 2,283 households had registered.
Sam Ferguson, program coordinator for communications and outreach, said he hopes to see more people join the program.
“The higher the participation rate of people sending food scraps, the better our technology becomes,” she said. The better the technology gets, the easier it will be for other local governments to adopt it.
Residents of Maplewood, North St. Paul, Cottage Grove and Newport can sign up for the food scraps pickup program at foodscrapspickup.com.
A timetable for adding other Ramsey and Washington County cities has not yet been decided, Garletz said. Those residents can still bring food scraps to drop-off locations and can sign up for updates on the website.