backlight whose bulb contains mercury. Old CRTs have lead in their monitor glass. Even that humble iPod is stripped of its battery, which, I’m told, can be tricky because bending them can have unfortunate consequences. Toner and ink are also put aside for proper disposal.

Once the safety hazards have been removed, the remainder of the device, known as the carcass, is tossed into a large cardboard box. Or if it’s something too big to fit, such as a photocopier, it’s moved aside until it’s time to meet its doom.

As they’re filled, the boxes are scooped up by one of many forklifts zooming around the plant, and deposited onto a conveyor belt. That photocopier we left lying around is ushered to an elevator; its destination is the same, a giant shredder that munches the equipment into chunks (the cardboard boxes and pallets are rescued and reused). Those chunks are fed to a second shredder that chews them up some more, and its output goes to a third shredder that emits pieces about two inches in size.

Okay, so now we have little pieces, but they’re composed of all sorts of different substances. Next comes the sorting process.

First, the output stream passes over a screen. Little pieces of wire and other small objects ( 4 to 6 percent of the material) fall through, and are sent to a smelter that cleanly melts them down and incinerates plastic coatings without polluting the atmosphere.

Next, magnets snatch up any ferrous metal from the mix. That accounts for about 40 percent of the material, and it, too, ends up in a smelter.

Finally, clean aluminum is extracted by an eddy current separator, a device that uses each substance’s conductive properties to sort out the valuable metal.

Now we have a mish-mash of bits of plastic, old circuit boards, and components left to deal with. According to Sims, although the company is currently running a pilot project to separate and recycle certain kinds of plastic, for the moment the bulk of leftovers are sent to the smelter, incinerated (and emissions scrubbed to contain airborne toxins), and the remaining metals recovered.

Back at the Sims plant, the job isn’t over. The company not only has to safely break down the recyclables, it has to ensure that the residue of its work doesn’t pollute the environment. Even the dust in the air is collected and sent off for processing to recover metals, and the drainage system is isolated to ensure that anything unpleasant can be intercepted before it escapes. Employees are regularly tested as well to make sure they haven’t been exposed to bad things.

The bits and pieces deemed toxic are then sent off for proper destruction or reclaiming (believe it or not, the mercury in those backlights can be recovered and reused).

When this “mining” operation is complete, the result is environmental savings on multiple levels. Reclaimed metal is metal that doesn’t have to be dug out of the ground; that doesn’t mess up human, plant, and animal habitats; and doesn’t have to be extracted from ore, leaving huge piles of waste. And equipment that is recycled doesn’t litter up our already overtaxed land-fills, and doesn’t have the opportunity to leach chemicals into soil and ground water.

And it also gives us nice empty drawers and closets to fill up with mor~e of our for- _{merly adored electronic toys.}

DOI: 10.1145/1377016.1377019

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