How are metals, glass, plastics, and carton recyclables sorted at the Materials Recovery Facility (MRF)?
at the MRF
In NYC, commingled metal, glass, plastics, and food and beverage cartons are set out for recycling collection in clear bags or properly labeled recycling bins, separate from paper and cardboard recyclables (see what to recycle in NYC).
Department of Sanitation workers collect the commingled metal, glass, plastic, and cartons together in a truck, and transport the load to one of the Materials Recovery Facilities (MRFs) owned and operated by Sims Metal Management Municipal Recycling , a private firm holding a long-term contract with NYC to accept, process, and market these materials (see what happens to NYC's recyclables).
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At the Materials Recovery Facility (MRF)
In order to market, or sell, recycled items to buyers who will turn them into new products, Sims must separate the different material streams that will be of value to a buyer.
To do this, the commingled loads are fed through different kinds of sorting equipment, and workers also manually separate material.
Magnets attract ferrous metals (steel) from the mix, then electrical currents separate aluminum cans and foil. Glass, which is crushed into glass "cullet" less than two-inches in size, is sifted out of the mix through a screen. Slightly larger items, mainly plastic caps and lids that have popped off during this processing, fall through a second screen.
Rigid (hard-sided) plastic containers move past a series of optical sensors that identify different types of plastic, including #1 PET, #2 HDPE, and #5 PP. Air jets blow off each type of plastic into its own bay to be baled.
Workers stationed along the conveyor belt pick off beverage cartons for recycling. They also pull out other recyclable material that did not get separated by the equipment.
Plastic bags and other objects that were mistakenly included in the recycling (TV's, bowling balls, etc.) are caught and removed manually. These items cannot be marketed and must be discarded as refuse.
Sims tries to find buyers for the mixed material left over at the end of the conveyor belt journey. If no market can be found, it is disposed of as refuse. (See quantities of different plastics in NYC's waste for more info.)
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The process described above extracts about 80% of all deliveries as baled metal, glass, beverage cartons, and plastic with weak to strong markets. The rest is material that has no recycling market and must be disposed of as refuse.
The energy, labor, time, and technology needed to run this system all cost taxpayers money. The viability of the system requires material to move through consistently, yielding enough marketable material to cover the costs of sorting. The goal is to extract most of the value from most of the material that moves through the system at a reasonably efficient rate.
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what happens to nyc's recyclables
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