About the Materials Recovery Facility
Once the recycling truck has emptied your toter full of single-stream recycling from the curb, it heads to Casella's Auburn Material Recovery Facility (MRF). An MRF is a facility where the recycling (material) is sorted into various commodities (recovered), baled and shipped out to mills that further process the material. The MRF is available for school tours!
The recycling truck gets weighed on the scale at the MRF and then goes to the tip floor to offload the material to be processed. When the truck is empty, it goes back across the scale and gets weighed a second time to get a net weight of the material it just offloaded. The truck leaves the facility to pick up more material curbside, but what happens to the material after that?
A loader pushes the material onto a belt that has a drum to help meter the burden depth of the material. The material is pre-sorted to remove what people put in the recycling that should not go there. Plastic bags, styrofoam, and large metal objects are removed so that they do not damage the equipment.
The material runs over the Old Corrugated Cardboard (OCC) screens. The OCC screen is a series of disks that the material runs between or over. Cardboard floats over the disks and paper, plastics, and metals fall onto one belt, while smaller material like glass, small pieces of paper and bottle caps fall onto a separate belt.
The smaller belt runs up to the next piece of equipment, which acts as a vacuum and sucks up the paper but keeps the glass on the belt. The glass is collected at that point and is ready to be shipped to a local mill. The material on the other belt (all the paper, plastic, and metal) goes through a paper screen that separates the paper with a series of angled, rotating disks. What the paper screen doesn't catch goes through a V Screen, where it is quality controlled, dropped into a compartment, and baled.
The remaining material falls through the center of this V Screen onto a belt. This belt runs under a magnetic belt that picks up tin and deposits it into a bunker, where it waits to be baled.
The material is then hand-sorted for 1- and 2-type plastic and the remaining material goes through an optical sort PET. The optical sort determines the type of plastic and blows a jet of air to send the plastic into the correct bunker to be baled.
The remaining material goes through an eddy current that sorts the aluminum by using a reverse magnet.
Any material that remains is re-run through the entire system to be properly sorted. Material in bunkers is baled with a giant compactor that secures the bale with wire. The bales are stacked until there are thirty of each product. Then, a truck picks up the material and delivers it to a mill for further processing.