Where Christmas Lights Go to Die (and Be Reborn as Slippers)

By Veronique Greenwood | December 28, 2011 11:17 am

The holidays are hard on Christmas lights. Exposed to the vagaries of small nephews and exuberant pets, most strings will experience a few casualties, and while a missing bulb no longer means the entire set stops working, Americans still throw out millions of pounds of lights a year. Adam Minter, who’s writing a book on the globalization of recycling, describes exactly what happens to your old lights when they’re shipped over to a concern in China, which, ironically, makes better use of minced-up lights than any US company could.

Workers untangle the lights and toss them into small shredders, where they are chopped into millimeter-sized fragments and mixed with water into a sticky mud-like substance. Next, they’re shoveled onto a large, downward-angled, vibrating table, covered in a thin sheen of flowing water.

As the table shakes, the heavier flecks of copper (from the wire) and brass (from the light bulb sockets) flow in one direction, and the lighter plastic and glass (from the insulation and bulbs) flows in another. It’s the same concept that miners use when panning for gold, and the results of this updated, age-old technology can be found at the far end of the water tables: baskets of roughly 95% pure copper and brass alongside baskets of insulation and glass. The contaminated water, meanwhile, flows into a recovery system, where it’s re-circulated, over and over, through the recycling system.

Recyclers in China, Minter explains, actually reclaim more of Christmas lights’ component parts than American recyclers do. Copper has good resale value in the US, but the plastic insulation, which is used to make slipper soles in China, and mixed copper and brass pieces, which the Chinese refine for use in manufacturing, have no market in the United States. So American companies send them to the landfill, while the Chinese sell them on to be used again.

  • Paul D.

    It’s more important to recycle the copper and zinc in the metals than it is to recycle the carbon, hydrogen and chlorine in the plastic. The latter are available inexhaustibly, while the metals have to be mined from leaner and leaner sources.

  • John D

    Plastic are made from petroleum, hardly inexhaustible.

  • http://oceanobservations.blogspot.com/ Sara M.

    My question is why can’t the plastic be recycled into something useable like slipper soles in the U.S.? You see things like old flip flops being made into mats under playgrounds. I imagine it would be a similar process.

  • Paul D.

    John D.: plastics are currently made mostly from ethane and other light hydrocarbons, derived mostly from natural gas. But even if fossil fuels become unavailable, plastics can be made from any carbon-containing feedstock, including biomass or even CO2 (with enough energy input).

    Copper, on the other hand, is copper, and unless you’re doing transmutation it has to be either recycled or mined.

  • Geack

    @ Sara M 3. : When was the last time you bought a pair of plasitc slippers made in the US? Just too darn expensive. No point in recycling materials for something you don’t make. And, no, the two processes aren’t likely that similar. The playground mats you’re talking about are made from a very simple, low-effort process of basically grinding up the rubber and binding the chunks togehter with heat. Anything more complex than that gets much more expensive, which makes it impractical even if the US had a use for the material. Sad but true.


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