Scrap Metal Separation May Become
Less Costly
Scrap Metal Separation May Become Less Costly
http://learningenglish.voanews.com/content/article/2685935.html
Recycling, or re-using, metals is much less costly than making them from rawmaterials in
the Earth, called “ore.” But when old cars, household appliances
and industrial equipment are thrown away, metals are mixed and often difficultto separate
. So they are usually placed into landfills without being separated.
The United States Environmental Protection Agency says almost 15 milliontons of this
“scrap” metal is placed into landfills every year.
Although iron and steel are easily separated with strong magnets, othermetals, such as co
pper, aluminum and titanium, are
not. So products with amix of these metals are either sent to landfills or
to other countries, whereworkers separate the different metals by hand.
But university scientistsworking with a private company say they have created a very acc
uratemethod to separate these light metals, using a machine.
Don Eggert is the founder of
O2M Technologies. His company worked withthe University of Utah to develop the meta
l separation technology. Mr. Eggertsays the system is based on
the knowledge that all metals react to a strongmagnetic field.
“When the metal falls through the field, even (if/though) it’s non-ferrous, it’s
not attracted to the magnet, but the magnet causes there to be
an electriccurrent inside the metal, and
that causes the metal to have a magnetic fielditself, which interacts with the magnetic
field that it’s falling through andpushes it to the side.”
Mr. Eggert says changing the frequency of
the magnetic field causes metalpieces to fall into different containers.
“So,
for example, if we want to separate aluminum and copper we hit the rightfrequency for it
and the aluminum would push more (further) away from
themagnet than the copper will. So the copper falls straight down, (and)
thealuminum falls into a different bucket.”
Mr. Eggert says the separator is not costly to build.
“What we have calculated so far is that the expense-to-value ratio -- that
is,how quickly you can pay back the cost of the technology over time -we’recurrently estimating it to be less than one year.”
The separator works only with metal pieces up to one centimeter wide. But
the researchers are building a bigger magnet to separate larger metal parts.They hope to b
egin operating it at a metal shredding center by the end of thisyear. There, they will
be able to test it in a real-life environment.
I’m Jonathan Evans.
George Putic reported this story from Washington. Jonathan Evans wrote it for
VOA Learning English. Christopher Jones-Cruise was the editor.
________________________________________________________________
Words in This Story
appliance – n. a machine (such as a stove, microwave or dishwasher) that
ispowered by electricity and that is used in people’s houses to perform aparticular job
accurate – adj. able to produce results that are correct; not making mistakes
ferrous – adj. of, relating to or containing iron
magnetic field – n. of or relating to a magnet or magnetism;
the magneticeffect of electric currents and magnetic materials
frequency – n. the number of times that something such as
a sound wave orradio wave is repeated in a period of time
What happens to scrap metal in your country? We want to hear from you.
Write to us in the comments section.