This article was extracted with permission from "Stuff: The secret lives of everyday things" by J. Ryan and A. Durning. Published by Northwest Environment Watch, Seattle WA, 1997.
The beige computer that stares at me 40 hours a week consists of about 55 pounds of plastics, metals, glass, and silicon. But the heart of this fantastically intricate machine is one-fiftieth of a pound of silicon and metal formed into integrated circuits, also known as semiconductors, or simply chips.
Though the chips weigh next to nothing, making them generated more waste than making any other part of my computer. The 400-step process of making chips and covering them with millions of microscopic electrical switches began with silica mined in Washington. Silica, or silicon dioxide, the basic ingredient of sand, is the most abundant substance in the Earth's crust. The silica was heated with carbon in an Oregon plant to form carbon monoxide and 98 percent pure silicon. This silicon was heated with hydrochloric acid, then with hydrogen gas, and cooled to form a "hyperpure" silicon rod eight inches across. The crystalline rod was sliced into wafers less than a millimeter thick, and these chip's were ground and chemically polished to a mirrorlike shine and trucked to the chip manufacturer in California's Silicon Valley.
The chip factory, called a wafer lab, stretched longer than two football fields and housed equipment manufactured by more than 100 companies around the world. My computer's chips--one wafer's worth--were made in "clean rooms," where only one to five particles were present in each cubic foot of air and workers wore gowns, booties, and gloves to avoid contaminating the wafers. In contrast hospital operating rooms have 10,000 to 100,000 particles per cubic foot; outside air contains 500,000 to 1 million particles. Keeping these rooms particle free required pumping the inside air through special filters that removed fine particles. But the filters did not remove solvent vapors, some of which were toxic, from the air the workers breathed.
My silicon wafer was cleaned with acid, then heated to form a protective surface layer of silicon dioxide. Workers looking through microscopes used ultraviolet light, light-sensitive chemicals, chemical developers, patterned masks, and some of the most precise machinery ever invented to etch a pattern of minute circuits across the wafer. Further etching created holes in which high-energy machines planted phosphorus and boron, which would eventually carry electricity through my finished chips. Each of these steps was repeated several times, and after most of the steps, the chips were chemically or mechanically cleaned.
Producing the chips in my computer generated 89 pounds of waste--4,500 times the chips' own weight!--and used 2,800 gallons of water. State-of-the-art wafer labs could have made the same chips, allowing me to do all the same computer tasks, with less than half the waste.
Paper-thin layers of Arizona copper were applied
to each chip's surface, chemically etched (to create the wiring connecting
the chip's circuits), cleaned, then oxidized for insulation. Machines applied
an even thinner layer of gold to the back of each chip. After more chemical
cleaning, a ship carried my wafer to Malaysia in a box of unbleached Oregon
Douglas-fir pulp with shock-absorbing inserts of black polypropylene foam
from Japan. The shippers would reuse the box and the foam inserts six times
before recycling them.
In a factory operating around the clock near Kuala Lumpur, Malaysian workers earning about $2 an hour and Japanese robots running on coal-fired electricity cut my wafer into hundreds of individual chips and assembled them into "packages." Each package consisted of a chip, frame, wires, and plastic housing. The packages enabled the chip to be wired to the rest of my computer.
Face-masked, gloved workers glued each chip to
an etched copper frame, ran tiny wires of South African gold between the
frame and the chip, and molded a plastic compound around the package. Because
gold is so expensive, almost none is wasted. But because it is so expensive,
gold miners can profitably mine ores that have less than one part per million
of gold, leaving behind huge piles of mineral waste contaminated with toxic
metals and the cyanide used to extract the gold.
My completed chip packages were shipped back to the United States.There my computer manufacturer inserted them into printed circuit boards in the disk drives, keyboard, and other devices, as well as into the "motherboard," the main circuit board on which most internal components are mounted.
A Texas factory made my circuit boards. Their manufacture used more chemicals, energy, and water, and generated more hazardous waste, than the making of any other part of my computer. Machines cut boards made of copper, fiberglass, and epoxy resin to size, drilled holes in them, and cleaned them. In a process not unlike making chips, the holes were plated with a thin layer of copper and the boards etched with circuit patterns. This process generated airborne particulates, acid fumes, VOCs, and other chemical wastes.
Then the boards were plated with layers of copper and of tin-lead solder. The tin was imported from Brazil, and the lead was recovered from dead car batteries in Houston. Recycled lead meets 60 percent of U.S. demand annually. The United States consumes half the world's lead, mostly for car parts. Because lead is highly toxic and hard to dispose of legally, 90 percent of car batteries are recycled after use. Yet lead waste from electronic goods is almost never recycled. Scattered throughout the computer, lead solder is costly to recycle.
Etching and cleaning left behind a pattern of copper wiring on the circuit boards. Assembling and soldering the boards also produced lead, copper, VOCs, and solvent wastes.
When I use my computer, I don't see the chips, chip packages, and circuit boards hard at work on the inside. All I pay attention to is what appears on the screen--the wide end of a cathode-ray tube (CRT), a vacuum tube made of glass with electron guns at the far end. Like almost all computer monitors sold in the United States, my CRT was made in Japan.
A manufacturer in Osaka used various chemicals and ultraviolet light to etch a minute pattern of black stripes and then red, green, and blue phosphors on the glass for my monitor's front panel. Every color I see on my screen is actually a combination of these three colors.
The sides of the CRT were soldered to the front panel with lead oxide and heated, fusing the parts together to form a bulb. Discarded color monitors are classified as hazardous waste because of lead in the glass. By the year 2005, about 150 million personal computers will have been sent to landfills in the United States. They will occupy about 300 million cubic feet, equivalent to a football field stacked a mile high in computer trash.
Ships, planes, and trucks, brought the various computer components to the California plant where they were assembled. The finished computer was carefully boxed with polystyrene foam inserts and trucked to a suburban superstore. I ordered it over the phone; a delivery truck brought it to my office.
In all, the factories making my 55-pound computer generated 139 pounds of waste and used 7,300 gallons of water and 2,300 kilowatt-hours of energy (about one-fourth the energy the computer would use over its four-year lifetime). State-of-the-art factories could have made the same computer with half to two-thirds less waste. And different computers--with flat-panel displays (like those in laptop computers) instead of todays' big vacuum tube monitors, for example--could have been made with even less waste.
The computer industry thrives on the rapid adoption of new technologies and resists change much less than older industries. If nudged by governments and consumers, the computer industry could apply its technical expertise toward cleaning up its own act--and fast.
I stepped out to grab some lunch. I left my computer on.
What to do?
× Turn off your computer, or at least your screen, whenever you're not using it.
· Choose the most power-saving settings in your computer's setup. Look for EPA's Energy Star logo if you buy new equipment.
× If you need to upgrade your computer, have new memory or circuit boards added rather than replacing the whole thing.
· If you need a new computer altogether,
refurbish a used one or buy a laptop, before buying a new desktop. Laptop
computers weigh about one-tenth as much as desktop computers and require
about one-third the electricity.
In fact, for a typical computer system, it takes
at least as much energy to make a year's worth of paper as it does to run
the computer for that time. Computers were supposed to herald paperless
offices, but with multiple drafts and reprinting to correct every little
error, computerization has probably increased paper--and energy--demand.
Garbage In, Garbage Out?
|Total Waste||Hazardous Waste|
Does not include other computer components or
waste from raw material extraction
About 700 different materials and chemicals went into manufacturing my computer; half of these were hazardous. Computer plant workers exposed to toxic chemicals have suffered lung diseases, skin rashes, and even increased rates of miscarriage. Electronics manufacturers have bestowed California's Silicon Valley (Santa Clara County) with large areas of contaminated groundwater and the highest concentration of Superfund hazardous waste sites in the United States.
Chemical use and pollution remain heavy in the
industry, but computer manufacturers, at least in the United States, have
made progress in reducing their toxic releases. According to EPA's Toxic
Release Inventory, computer manufacturers generated 10 million pounds of
toxic waste in 1990, two-thirds less than they did in 1987.
The computer's 2.5 pounds of copper began as copper sulfide ore, nuch of it mined from the Chilean Andes for export to Asia, By law, 10 percent of Chile's copper revenues go to the Chilean military.
If the ore contained 0.9 percent copper (the global industry average), making my computer required excavating 280 pounds of ore and at least 300 pounds of other rock lying on top of the ore. The ore was pulverized, mixed with water and chemicals, and boiled to obtain pure copper. Boiling also produced sulfur dioxide (5° 2)l which causes acid rain. Worldwide, the SO2 emitted in copper production is equivalent to one-fourth the SO2 emissions of all industrial nations.
Though my computer contains less copper than my car (40 pounds) or the pipes and wires in my house (even more), it was enough to have a big impact. Mining, crushing, grinding, and smelting the 2.5 pounds of copper required the energy equivalent of 73 gallons of gasoline. Mining and producing metals accounts for about 7 percent of global energy consumption.
A glassworks in Kobe made the glass for the front of my monitor, using mostly local sand and electricity from a power plant burning Australian coal. The glass also contained 5-10 percent each of strontium oxide (from Mexican ore), sodium oxide (from local salt), potassium oxide (from Russian ore), and barium oxide (from Chinese ore).
A different manufacturer made the CRT's sides. Its glass contained 22 percent lead oxide (to absorb x-rays generated by the CRT) from Australia and was coated with graphite made from Saudi petroleum. Because a monitor contains five different types of glass, and their compositions vary by manufacturer, the glass from old monitors is seldom recycled.
Hi John, I do not mean to pick on you and I am aware that you are not the author of this article. I also agree with you when it comes to think that the semiconductor industry wastes much energy and material and happily pollutes around the world. What bothers me in the article are small inaccurate details spread throughout. The details that I have problem with are relatively minor in a sense but spoil the impact of the writing. For instance, it starts with the silica mined in Washington. Clean sand found around the world is usually the starting material but the state of Washington or Oregon are far from being significant sources. Silicon crystals are no longer produced in substantial quantity in the US most of the production has migrated to the Far East. Silicon is used in many common metal alloys such as steel or aluminum. Producing silicon raw material involves carbon to reduce the silica, not hydrofluoric acid. The environmental problems start when producing the crystals from the raw silicon because of the large amount of energy needed for the furnaces to melt the silicon. Dicing and polishing the wafers uses huge amount of water in conjunction with hydrofluoric acid that is not a particularly friendly acid. Cheap sources of power and water made the Vancouver WA area attractive to the silicon refiners and to the growth of silicon ingots where for instance SEH America Inc employs 1,800 people and Wacker Siltronic employs 1,700 people in Portland OR. Komatsu and Mitsubishi (Salem) are also nearby have but very small plants. The Pacific Northwest plants are threatened by the poor economy arising from the growth of manufacturing in China where labor is cheap and you can pollute your heart content without contending with an EPA. Some US plants are outrageous resource drains for example the Shin-Etsu wafer plant, north of Phoenix AZ, is depleting the water table under the desert and justifies its presence because the peons are even cheaper in Arizona than in Oregon and Intel and ON (ex Motorola) are nearby. Other examples are that nobody uses ultraviolet light to pear through microscopes, gold has not been applied to the back of chips for decades, the silicon industry in Japan has decreased to noise in the background for the same economical reasons prevailing in the US. Cyanide is too expensive to throw in the gold extraction waste, the circuit board industry no longer pollutes much in the US because of regulations but pollute in the third world. Most CRT or flat screen panels are no longer made in Japan but in China. Packaging chips has not been done in the US for 30+ years, even Mexico is too expensive for assembly, all this is done in Taiwan, Singapore, China, Korea etc. I could go on and on... Two and a half pound copper in his 55 lbs computer? My 64 bits AMD computer weights 1/3 of that and you certainly would be hard pressed to find more than 200 grams of Cu. Yes, much needs to be done to recycle the water or stop wasting gobs of energy because it is cheaper than cleaning one's act but I am only a coyote howling in the dark. It does not stop the caravan. Regards, John