Watch Now: Here’s How Midwest Fiber Sorts Your Recycling | Local News
Tilting floor and dosing tank
Garbage trucks—private haulers, municipal trucks, and Midwest Fiber trucks—that roam the city picking up recycling stop at Midwest Fiber to dump loads of garbage on the tip floor. A small loader truck picks up the materials and transports them to the batch bin – the first machine in the sorting process – where the materials are evenly laid out on a conveyor belt at a depth of approximately 6 to 8 inches.
Midwest Fiber staff members stand along the treadmill and remove any objects that could damage the system or not pass through it properly. Items workers look for at this point to remove the treadmill include large pieces of metal, plastic bags, wire, electronics, large plastic buckets, and containers.
Old corrugated containers
The materials then drop into the OCC screen, which is a rotating wheel designed to separate large pieces of cardboard from smaller materials. Cardboard will be carried up and over the wheel into a holding bunker, while smaller pieces will fall through holes between the spinning discs. The glass is broken inside the spinning machine and sent to a storage bunker outside the facility.
Documents that have passed through the pre-sort and OCC screen are sent to the news screen, which aims to separate the paper from the rest. Operating similarly to OCC, materials are sent over a conveyor belt and a series of rotating discs to separate the containers from the paper. The containers fall between the discs and move on to the next stage, while the paper goes up another conveyor belt.
Containers and other materials that were sorted from the paper in the previous step are now sorted by size on the polishing screen. Another series of rotating discs help push the materials, and a steep slope at this point allows heavier three-dimensional items to fall on a different conveyor belt, while two-dimensional items like paper move along its own line.
The two-dimensional articles that have moved through the polishing screen then land on the fiber lines. Midwest Fiber employees stand along a conveyor belt sorting out items that shouldn’t be there, like plastic bags, small pieces of cardboard and flattened containers. The rest of the materials, mostly paper, fall into the bunker containing mixed paper.
The three-dimensional materials that fell through the news and the polishing screens land on the container line. The Cross Belt Magnet, which is a strong magnet that spins on the container line conveyor belt, pulls the steel and tin materials off the line and separates them into its own holding bunker.
After the cross-belt magnet removes all of the steel and tin materials from the three-dimensional material line, the rest of the containers move along the container line, where employees sort the plastics by type. Each worker looks for a specific type of plastic to sort from the line – for example, one worker will monitor #2 plastics without dyes or dyes, such as milk jugs, while another worker will sort #2 plastics with dyes and dyes, such as detergent containers. Another employee will sort through any materials that slipped through the cracks in the previous steps, such as books or boxes.
Materials remaining after all the previous steps, such as aluminum or polyethylene terephthalate bottles, or PET (single-use plastic water bottles), are directed to the eddy current, which is designed to separate the aluminum rest. The machine imparts a positive charge to the foil, blasting it off the tape and over a splitter bar to a holding bunker.
The rest of the materials that have gone through the process then go through the optical sorter. This step separates PET bottles, such as single-use plastic water bottles, from the rest by blowing air on any items it recognizes as PET plastic. The air jet pushes these bottles out of the conveyor belt to be manually sorted and then taken to a storage bunker.
All of the materials that were sorted through the process eventually fell into its own holding bunkers at various stages. Once a bunker is full, an employee transports it to the baler, which condenses the donated material into cubes. Each cube could weigh between 1,200 and 1,800 pounds. The cube of that specific material is tied with wire, moved to storage, and is ready to ship. Semi-trucks or train wagons pick up the cubed materials to transport them to recycling plants where the items are turned into new products. Midwest Fiber ships its materials from Beijing to Indiana, Wisconsin, Georgia, Mexico, China, Taiwan or India.
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Contact Kade Heather at 309-820-3256. Follow him on Twitter: @kadeheather