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1 Rags and Bottles In 2002, I toured a glass-beneficiation facility, a plant whose sole purpose was to ready recycled glass to make new bottles, fiberglass, and high-end sand substitute. Beneficiation facilities are a second stop after glass containers go through a first round of sorting at a materials recovery facility (abbreviated as MRF and called a “murf” in the recycling business). Bottles and jars that residents set out with their cans, plastics, and other recyclables rarely arrive at materials recovery facilities intact, but even those that do are sure to get broken as they proceed. As mixed recyclables move along a conveyor belt, a combination of magnets, electrical currents , air jets, and hand picking remove metal, plastic, and paper, leaving only glass. As glass is sifted out of the moving mix, it emerges crushed, mixed with food residues and bits of label. In this form, known as “dirty mixed cullet,” it is not good for much. At best, it can be used as lowgrade fill or as what is known as “alternative daily cover,” a substitute for the earthen layer that must cover each day’s load of trash at the landfill. If it is going to become anything more, it has to be shipped to a beneficiation facility to get cleaned and color sorted. In the facility I visited, what was being delivered looked like something you would find under your car’s backseat if you hadn’t cleaned it for ten years. To me, it was unrecognizable as glass. But as this mass of gooey, crunchy, whitish material moved through the facility, it was bathed in water, dried with high-speed jets of air, and crushed to a uniform size. Gradually, it began to look like glass again. Optics took over from there—beams of light calibrated to the refraction of clear, brown, and green hues shot through each shard, classifying and then sorting it, with a blast of targeted air, off the belt and into a bunker below. As the now sparkling, gemlike pieces moved along the conveyor, they were neatly blown into gleaming piles by color. After optical sorting, small pieces of plastic and metal as well as an interesting array of china 24 Chapter 1 and ceramic bits were left over, all destined for the landfill. The point of glass beneficiation was to yield green glass that could be shipped to Europe to make new wine and beer bottles, brown glass that would stay in North America to be used to make beer bottles, and the highest-value output—clear glass that could substitute for as much as 30 percent input in the production of a new bottle or jar. Pieces too small to be color sorted were crushed to a fine dust that was utterly indistinguishable from sand. Safe to pick up and handle, this material would also go to beneficial use as sand substitute. As I watched this amazing technology at work, part of me was awed at the precision of the optics and cheered by the restoration of a mass of muck into cleanly sorted piles of useful material. Another part of me was dismayed, however, at the long journey and expenditure of energy and money that these pieces of glass had needed to take from the moment they were set down beautiful and intact in someone’s home. Had the shards in question been extremely valuable, rare, or toxic, such costly, transportintensive , and painstaking attention might have made sense. But as I discuss in this chapter, none of these qualities applies in the case of glass. Several years later I worked on a large and fascinating project whose goal was to sample and classify what was in the garbage that residents of my city discarded everyday. Crews of workers stood around tables, carefully teasing apart the contents of black trash bags into categories of organic and inorganic material. Each category had its own bucket into which sorted items were tossed; these buckets surrounded the sort tables, filling up with separated rotting food, diapers, unrecycled metals, plastics , paper, variously colored glass, and other wastes. Among the buckets were two marked for textiles—one for clothing, another for linens and home furnishings. To my surprise, the clothing bucket filled to overflow each day with clean, intact, and often fashionable apparel. In the other bucket, forlorn but still fluffy stuffed animals, lace curtains, and towels with tags on them burgeoned. Dirty rags were...

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