This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
Chances are, what happens to your recycling once you set it out by the curb is a mystery. Maybe once a week, or like in Austin, every two weeks, the good people from the City swing by in large trucks and take away 96 gallons worth of cardboard, glass, and plastic. I feel good about myself when I dump items in the recycling bin, and I imagine the landfill breathes a gentle sigh of relief, too.
As a nation, we toss about 250 million tons of trash each year. Another 87 million tons heads to recycling centers. That works out to about four-and-a-half pounds of garbage per person each day, where nearly one-and-a-half are recycled. More and more cities are offering what’s called single-stream recycling, where you dump all recyclables together in to one bin. Someone else does the sorting.
But what happens to those glass bottles, endless advertising inserts, and water bottles once you toss them in the bin? How is it all sorted?
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NPR’s Jess Jiang and Lam Thuy Vo visited a murph – that’s Materials Recovery Facility (MRF) – in New Jersey to see how one item, a glass bottle, goes from being a used glass bottle into a new glass bottle, told in six animated GIFs.
The story is one of Rube Goldberg contraptions made of conveyor belts, shakers, vacuums, and magnets that shake and sort the various materials. The optical scanner, which takes pictures of items as they pass along a conveyor belt, can capture specific materials at will using a puff of air.
For the glass bottle in question, Jiang and Vo trace its journey as the glass is broken up and then mixed together with other ingredients for making glass bottles (soda ash, limestone, and sand). The ingredients are then melted down together at 2,700 F in a massive furnace.
Globs of glass are blown in to bottles, glowing orange as they cool down. Once cool and solid, the bottles are ready to be filled with your favorite beverage and await your purchase at your local grocery store. And likely, thrown in to the recycling bin for another journey. Here is a video of Jess Jiang and Lam Thuy Vo's story:
For another look at a MRF, Waste Management, the nation’s largest hauler awayer of our undesirables, gives a fun corporate-y tour through a flagship facility in Philadelphia. I’ve fast-forwarded to the good stuff. Enjoy.