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New metal recovery methods save energy and the environment

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From VOA learning English, this is the Technology Report. PLAY

Recycling, or re-using, metals is much less costly than making them from raw materials. But when old cars, household appliances and industrial equipment are thrown away, metals are mixed and often difficult to separate. So they are usually placed into landfills. PLAY

The United States Environmental Protection Agency says almost 15 million tons of this “scrap” metal is placed into landfills every year. Although iron and steel are easily separated with strong magnets, other metals - such as copper, aluminum and titanium - are not. Products with a mix of these metals are either sent to landfills or to other countries, where workers separate the different metals by hand. But a group of scientists say they have created a machine to separate these light metals. PLAY

Don Eggert is the founder of O2M Technologies. His company worked with the University of Utah to develop the metal separation technology. Mr. Eggert says the system is based on the knowledge that all metals react to a strong magnetic field. If you drop the metals into a magnetic field, different metals react in different ways. PLAY

He says changing the frequency of that magnetic field causes the metal pieces to fall into different containers. In this way, they can be separated. Mr. Eggert says the separator is not costly to build. But it works only with metal pieces up to one centimeter wide. The researchers also are building a bigger magnet to separate larger metal parts. PLAY

For VOA learning English, I’m Alex Villarreal. PLAY

Source: VOA

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