7. The Many Steps of the Recycling Sorting Process

Sims-Municipal-Recycling-Facility-Sunset-Park-Material-Recovery-Facility-Brooklyn-NYCEDC-Untapped-Cities-NYC-014The orange boxes are the optical sorters

After the material goes through the liberator shredder, it goes towards disc screens that jostles the items while pushing them forward. The glass shatters, falls through the cracks and is collected to be sent to the facility in New Jersey. Then, the rest of the items pass over a drum magnet which pulls of all the ferrous metals (metal that contains iron).

Next, the plastics are sorted primarily using the 16 optical sorters (the orange boxes you see in the photographs) which are set to look for particular types of plastics and papers using infrared light. When the type is detected, an air jet is triggered at the end of the belt that shoots the item onto the next conveyor belt.

At this point, most of the plastic, glass and ferrous metal has been removed from the stream, and what’s left passes over an eddy current separator, a reverse magnet that charges metals that aren’t naturally magnetic. Metals like aluminum (the most common material removed using the eddy current), copper, brass, etc. will be repelled. Then, the remaining materials go through a trommel to remove the final unwanted pieces, and the final sort is done by hand.

Each of the separated products are then stored in a large bunker. When those bunkers are full, they will unload onto a conveyor and be sent to the balers. Through a large amount of the force, the balers compress the plastic or aluminum into bales that way about 1,000 pounds each. About 30 to 40 bales can be loaded onto a truck and sent to Sims customers, while other bales leave by rail and barge float.