![]() ![]() Most of the old CRTs being disposed of are in the United States and Europe, whereas the greatest demand for the material for making new CRTs is in Asia. The biggest issue in recycling CRTs is the imbalance in the centers of supply and demand. “We wanted to see how materials systems evolve over time.” We saw this as an interesting test case,” partly because it deals with a commodity that is gradually being phased out. ![]() “Our interest is in understanding how to make a materials system function in a healthy manner,” he explains, “both for economic benefits, and to minimize the environmental burden. Kirchain says the study was partly an attempt to develop a more general method for analyzing the flow of materials through the whole chain of production, use and disposal or recycling. In some places, including most European nations and Japan, they are included in a category of electronics waste that must be properly recycled, but recycling requirements in the United States and most of the rest of the world are inconsistent, or nonexistent.Īs a result, the study found that in terms of recycling glass from old CRTs to make new ones, “the amount of new glass required is decreasing, but is much greater than the amount of secondary glass collected, which is increasing.” That balance, the authors found, “is sustainable for the foreseeable future.” In other words, manufacturers wanting to use the recycled glass can count on having a supply, and recyclers can count on finding a market for the old tubes, for many years to come. Sales of CRT computer monitors peaked around 2000 at about 90 million units, but have already declined to near zero.īecause the glass used in CRTs contains a substantial amount of lead - used to block X-rays produced by the tube’s cathode ray gun to keep them from posing a health risk to viewers - the old tubes can potentially pose risks to human health if simply dumped in landfills. Virtually all of these CRTs are now manufactured in Asia. Sales of CRT television sets peaked in 2005 at about 130 million units worldwide, and declined to about 90 million last year - almost all of those in Asia and Latin America, where sales stayed roughly constant and are expected to remain so for several years. “That’s an early purchase one makes as one moves up the income ladder.” CRT television sets “are still absolutely the cheapest way to get a first TV,” says Randolph Kirchain PhD ’99, associate professor of materials science and engineering and engineering systems and co-author of the new study. The demand comes mostly from the world’s developing nations, where inexpensive TV sets using CRTs are one of the first luxury items people tend to buy as soon as they have a little bit of disposable income. But a new MIT study reports that demand for these devices is still greater than the supply of old discarded CRTs, whose glass is recycled to make new ones. Many people may assume that conventional television sets and computer monitors - the kind that use picture tubes (technically known as cathode ray tubes, or CRTs) rather than flat panel screens - have virtually disappeared from the market, like buggy whips and 8-track cassette tapes. ![]()
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