The Big Sort: A Major Upgrade to Charlotte’s Recycling is Coming – Charlotte Magazine

Standing in the middle of Mecklenburg County’s Material Recovery Facility, off West Craighead Road in northeast Charlotte, is like being in a version of Willy Wonka’s chocolate factory that processes anything but chocolate. The 100,000-square-foot warehouse contains an intricate array of loud, buzzing machinery and whirring conveyor belts filled with foul-smelling garbage, all rising to the ceiling alongside metal staircases and walkways that appear to lead nowhere.

The county doesn’t collect recycling from curbside bins. The City of Charlotte, and cities and towns within Mecklenburg, do. But the Material Recovery Facility, or MRF—pronounced “murph”—is where all of that curbside recycling ends up, some 80,000 tons of it every year. “If you’re in Mecklenburg County, you put your curbside out, they come to the facility, they’re sorted, they’re baled, and they go off to market,” explains Joseph Hack, a senior project manager for the county’s Solid Waste Division. Hack is a 35-year division veteran, and his matter-of-fact tone suggests he’s seen some things.

The county manages programs that handle 800,000 to 1 million tons of solid waste every year. About 500,000 tons goes directly to the Charlotte Motor Speedway Landfill in Concord, owned by Republic Services, the Arizona-based solid waste disposal giant that also operates MRF under contract with the county. The rest includes recycling that goes through four county-owned sites.

But major changes are coming in October, when work begins on a $26 million retrofit. “We expect an improvement in the recycling rates when we put the equipment in,” Hack says, “because it will be better designed for what’s actually in the market right now.” Work is expected to take 10 months, and the county will use its Hickory Grove recycling center as an interim MRF until the project is done.

The reason for the overhaul: Recycling has evolved since Charlotte implemented single-stream recycling in 2010. Two global events upended the industry. In 2018, China, in an initiative dubbed the Green Sword, stopped accepting waste from Europe and the United States. Municipalities could no longer ship solid waste, mostly paper and plastic, overseas for hand-sorting, which created a backlog and caused the value of recycled materials to plummet.

Then COVID-19 changed purchasing habits. As stores and restaurants closed, residents had more food and household items shipped to their homes. The additional packaging ended up in curbside bins, and MRF was unprepared to handle the increase. Hack says the upgrades will help the MRF capture more recyclable materials from the waste we already discard. That indicates a sea change in recycling philosophy: For decades, recycling has been primarily consumers’ responsibility.

Overall, the upgrade is expected to ease a problem few consider: extending the lifespan of the Speedway Landfill. Allowing more—and more kinds of—recyclables could mean less garbage dumped there and less need for a new landfill and the environmental hazards that would entail. It also may improve Mecklenburg County recycling rates that are headed in the wrong direction. In 2022, Mecklenburg’s ranking among North Carolina counties dropped from 14th to 16th in public per capita recycling.

Of the 500,000 tons that go to the landfill every year, 400,000 comes from weekly trash collection. Part of that additional tonnage, however, comes from materials going into the recycling center that shouldn’t be there, Hack says. Many people put items MRF can’t process—food scraps, ceramics, lithium batteries—into their curbside bins. He calls that “wishful recycling.”

The MRF’s overhaul will expand the system of sensors that separates types of recyclables—which will allow for a broader range of recyclable plastics.

Wearing a hard hat and a yellow safety vest over his dark quarter-zip, another project manager, Martin Sanford, greets many of the more than 30 afternoon-shift workers by name as he tours the facility.

Sanford starts in the middle of the building, where dump trucks enter through large garage doors and tip their loads onto the floor. The materials—paper (called “fiber” in the industry), glass, aluminum, tin, and plastic—are scooped onto conveyor belts at ground level. The belts rise to the roof as they enter and exit sorting machines encased in giant blue metal boxes. I try to keep up with Sanford as he points from one station to another, but it’s difficult to trace a path through the labyrinth. At the end of the process, the separated materials end up at the four corners of the building.

“The system, and in general most MRFs, are designed to sort three ways,” Sanford says. His deep voice booms over the din. “Sorting is based on the shape of the material, the size of the material, or the density of the material.”

Sanford, who will oversee the retrofit, explains that they use what’s called an eddy current separator to sort aluminum cans. That’s a fast-rotating magnet that creates an electrical “eddy current” that pushes out metals like aluminum—classified as “nonferrous,” or not containing iron. After that, other powerful magnets pull tin cans and other ferrous metals in another direction.

At the top of a flight of stairs, another belt runs under two electronic sensors, one that scans for 2D objects (fiber) and another for 3D objects (plastic bottles and aluminum cans that survived the eddy current). When the 3D sensor identifies an object like a water bottle, a hidden mechanism puffs air at it and sends the lightweight bottle flying off the belt. The 2D objects stay on the belt and descend again. Sanford explains that if people crush their bottles and cans to make more room in the bin or if they get smashed during transport, they become 2D objects and don’t go where they’re supposed to.

Next to last is glass. Since glass often gets broken during transport, it’s considered 2D and continues with the paper as it descends into a “hopper,” a large metal tray with 2-inch holes through it. Although you can’t see it, you can hear the glass break into smaller pieces as the hopper vibrates. Heavier glass—and anything 2 inches long or less—falls through the holes onto another conveyor belt that passes a giant fan, which blows away lighter detritus like bottle caps. Paper, which passes through the hopper, goes in another direction, where it’s pressed into giant bales.

Whatever’s left over ends up on the floor. If workers spot an intact aluminum can or plastic water bottle, they can collect it and put it in the proper place—but they often don’t have time for that. When they don’t, workers push-broom the remaining slurry into front-end loaders that scoop it into trucks bound for the landfill.

Sanford climbs a flight of stairs and enters the pre-sort stations, enclosed in a room about the size of a shipping container, above the moving belts. During their journey around the plant, two belts travel up and into this room, staffed by humans bundled in manufacturing’s version of PPE: thick coveralls or sweatshirts, steel-toed safety boots, ear plugs, neck gaiters, safety glasses, heavy-duty work gloves, and hard hats. They use crowbars to pull out plastic bags, the recycling industry’s biggest headache. Sanford says the new pre-sorting stations will have wider belts so workers can see the items coming to them sooner.

The plant’s retrofit will increase the waste handled from 30 tons per hour to 40 and sort glass at the beginning of the process instead of the end. “You see how far into the process we are pulling out glass, which is part of the problem because it gets mixed in with the paper and everything else. We’ll pull it out sooner. … It will put less wear and tear on the machinery because glass is abrasive, and as it’s running through the plant, it’s wearing on the belts.”

But the most important change is one that, on the surface, doesn’t seem revolutionary: an upgrade and increase in the number of sensors that separate 2D recyclables from 3D. The improved system will not only have 16 sensors instead of the current two. It’ll allow for a broader range of plastic containers the county can recycle.

The only kinds of plastics MRF can currently process are polyethylene terephthalate (PETE), or Number 1 plastic, used to make containers like water, soda, and mouthwash bottles; and high-density polyethylene (HDPE), Number 2 plastic, used for sturdier containers like shampoo, laundry detergent, and cleaning-product bottles. The new sensors accept items like drinking cups and clamshell food containers—objects that are easily crushed and end up in the 2D belt, where they don’t belong.

“Recycling will no longer be as much based on shape,” Hack notes. MRF’s current sorters identify recyclables by shape. The new ones will recognize resin types and more accurately distinguish between types of plastic.

Hack and Sanford hope the upgrade means a more efficient and environmentally responsible approach to recycling that will pay off for years to come. Like many essential public services, it involves a process that taxpayers happily leave to the professionals—just throw your bottles, cans, and wastepaper in the bin and forget about it. But the process matters, and on this day, I witness a procession of trucks with full beds stream steadily into MRF to offload their collections and leave to pick up more loads. The train of trucks operates on its own kind of conveyor—in, out, back in again—that serves as a reminder: After the overhaul, the machine will keep on running, and it’ll be needed more than ever.

The King of the Foam-Eating Lizards Is Hungry

The county enlists the help of a big, green dinosaur to promote plastic foam recycling

In 2022, Mecklenburg County’s Solid Waste Division founded a program called Enhanced Recycling that accepts items not allowed in curbside bins. People can drop off things like books, food waste, furniture, and clothing at any of the county’s four recycling and disposal centers. But the most important and popular item—one that inspired the rebirth of a creature long thought extinct—is white, rigid polystyrene foam, commonly known by the brand name Styrofoam.

At each of the recycling centers is a trailer-sized bin adorned with bright-green cartoon Tyrannosaurus rexes with a new designation. “Please Feed Our Foam-a-Saurus Rex,” reads the message on the side. “More Foam Please!”

From these bins, the foam is hand-fed into a densifier, a machine that heats and condenses it into 65-pound chunks of plastic that look like sausage as they come out. The program proved to be enough of a success to merit a second densifier, which allows the county to process more than 70,000 pounds of foam per year. Polystyrene foam is more than 90% air, so keeping it out of the landfill is a huge win, for humans and lizards alike.