Scrap tire recycling-a business that has needed all the help it can get-is showing more encouraging signs of taking hold. There's always been plenty of things to do with worn-out tires. They made wonderful mosquito-breeding areas for entomologists interested in studying various plagues. They have art potential (art being very subjective, of course): You could erect enormous amounts of tires into Christo-like artificial mountain ranges, or, on a more limited scale, turn tires inside out, paint them and, presto, you have a planter. I noticed one rural home outside Akron where a lengthy driveway is lined with such rubber delights. Interesting effect.
Actually getting rid of scrap tires, so they no longer waste space on earth, is a different story. Particularly when nearly 200 million ``new'' old tires are tossed per year onto the nation's heap of about 1 billion scrap tires.
Rubber recycling always has suffered from a lack of markets and the need for purity of ground rubber.
The markets problem is improving, although a potential large-scale use for ground rubber probably isn't going to happen. That's rubberized asphalt: The government mandate for mixing rubber with asphalt for roadways has succumbed to state and congressional pressure, and the fatal inability of its proponents to prove it can provide significant benefits at competing costs.
Instead, the hodge-podge of uses of ground rubber in low-tech goods or as filler is growing slowly. Eventually, if tire manufacturers fully embrace the concept of using crumb rubber in new-tire production-as a study by Michelin North America Inc. and Ford Motor Co. proposes-the business will get a major boost.
That brings up the purity question. No tire maker will use a material that lacks consistency. The rubber recycling industry knows this, and efforts at devulcanization are aimed at producing as much a virgin-like material as possible.
Today the scrap tire industry is working to set up standards for ground rubber. If-and hopefully, when-that happens, used tires will become a valued commodity, and not just an avant garde art form.
Noga is editor of Rubber & Plastics News.