White Paper: PC Recycling

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White Paper: PC Recycling

Very few of the components in your PC are biodegradable—and many are toxic—so dumping your old gear in a landfill is not only foolish but illegal. Besides, so many places will accept electronic waste these days that’s there’s really no excuse for not recycling your old rig.

Once your PC shuffles off to that great Start Menu in the sky, technicians can transplant its viable parts into ailing in-use systems. But if it’s too rickety for that procedure, recyclers can reincarnate it into an entirely new product. We find inner peace imagining our otherwise useless PII coming back as a flower pot or a pair of running shoes.

Reuse

Whether you drop off your old PC at your local landfill’s e-waste center or donate it to a charity such as Goodwill Industries, there’s a good chance it will wind up at a large domestic recycler. These recyclers facilitate and manage the entire process, even if they’re not equipped to handle each and every step. First, the organization logs the PC into its tracking system; next, employees assess the PC’s quality as a whole as well as its individual parts.

If the system functions properly and is not wholly obsolete—the line is typically drawn at Pentium 3–class machines—it can be donated or even resold intact. If it doesn’t meet those benchmarks, components (typically RAM, optical drives, and processors) that meet the company’s quality standards are extracted and delivered to wholesalers or refurbishers. In fact, nearly everything can be salvaged. Some vendors even buy undamaged cases and other cosmetic parts.

Although we recommend that you purge the data from any hard drive you discard, some recycling firms, such as the Texas-based TechTurn, will do it for you: “Our test department performs a functional test on the equipment,” explains William Long, TechTurn’s vice president of strategic partners, “and then erases all of the data from the hard drive and any other electronic media… in accordance with U.S. Department of Defense standards.” TechTurn accomplishes this by overwriting each sector with either random data or zeroes several times. If a bad sector prevents a rewrite, the recycler will typically physically destroy the unit.

Reduce

A massive shredder reduces aging electronics to quarter-size chunks at Hewlett-Packard’s recycling center in Roseville, California.

The actual recycling begins with a tear down and general parts sorting. Some recyclers manually divide the components into numerous streams, organized by part (hard drive, optical drive, keyboard) or commodity (plastic, copper, aluminum, steel); commodities are then passed on to specialty recyclers.

Hewlett-Packard recycles some PCs by removing hazardous materials, such as batteries, and then dumping the entire machine into a powerful shredder. In other cases, the company will remove printed circuit boards and then shred the enclosure. Either way, the recyclable materials are automatically sorted as they move down the disassembly line.

The shredder mulches the computers into successively smaller pieces until they’re coin size. As they pass over an 8mm wire mesh, soft metals such as gold, silver, and copper fall through. Magnets lift steel out of the pile, and the remaining rubble is dumped onto another conveyor belt and zapped with electricity. This action assigns a positive charge to any aluminum material in the debris. Just before the material reaches the end of the belt, a second positive charge ripples through it, which repels the aluminum bits and flings them into another sorting bin. At this point, the only material left on the belt is non-conducting plastic, which is dumped into a final collection bin.

Shredding is a less-common recycling technique because the process tends to eject particles that workers might inhale. But HP’s Tatyana Kjellberg, consumer program manager for the company’s Product Take Back service, tells us the company’s employees are well protected: “There are gloves and glasses at all times. When working close to the shredder and the metal-separating plant, they wear hard hats, just in case. [In] the shredding and separating section, there’s a huge filter attached to all the different separating sections. If there’s any dust or particles floating around, it pulls them in like a big vacuum.” Kjellberg maintains that HP’s air-filtration system is so extensive that the company’s employees don’t need to wear respirators or even masks.

Recycle

Once the primary recycler has extracted commodities such as aluminum and steel, it typically ships them to recyclers that specialize in the respective materials. CRTs, which can harbor considerable amounts of lead, are usually delivered intact to a company with expertise at separating that hazardous material from glass, plastic, and metal. Precious metals and printed circuit boards are often sent to a smelter for separation.

As these materials are slowly heated, each base element liquefies at a different temperature. The liquefied material is then drained off and the process is repeated until everything has been recovered. Since the smelting process can release hazardous materials into the environment, special filters and scrubbers are deployed to trap the potential pollutants.

Where does all this stuff ultimately wind up? Recovered plastic can be used in the manufacture of everything from shoes and roof tiles to park benches and storage bins. Metals recovered from old batteries during the smelting process can be recycled into fresh batteries. And the fiberglass recovered from printed circuit boards is typically used in the construction industry for concrete fill.

Revise and Redesign

The representatives of several companies we interviewed for this story told us that, in theory, they can recycle an entire PC in a closed loop, turning every used material into something new. But they also admitted that reaching that level isn’t always practical. Most companies manage to reuse 90 to 98 percent of the material in a personal computer. It’s often too expensive for a recycler not equipped with a smelter or a shredder, for example, to separate metal rivets embedded in plastic or thin copper wire from its insulating jacket.

That doesn’t necessarily mean the leftover material is bound for a landfill. If it can be incinerated safely, it can be used as fuel for generating electricity, recovering at least some of the energy required to produce it in the first place.

High-profile recyclers maintain detailed paper trails to keep track of the parts they take in and process, often hiring outside consultants, such as Environmental Resources Management, to act as outside auditors. Above-board recyclers avoid shipping recyclables to countries with lax environmental protections, and none of the companies we spoke to ships waste across borders. But dark corners remain in the recycling industry: “There will always be people down the food chain,” said ERM partner Kristyn Malina Rankin, “who will not do the right thing.”

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