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Aluminum cans
are the real success story of the recycling movement. By far, the most
valuable component in the consumer waste stream, they enjoy the greatest
public recognition as a recycled household item. Aluminum cans are often
the economic backbone of municipal and private recycling programs. The
price can fluctuate with the commodity price for new aluminum, but
aluminum can scrap has always had a strong price in comparison to other
recyclables.
Aluminum cans are collected
in a variety of ways. In some countries, cans are returned through
deposit schemes. With these systems you pay a deposit or fee when you
purchase a full container. When the container is empty, you return it to
a designated collection site and your fee is refunded. This collection
method is very effective but the cost usually exceeds the recycling
value for the containers. Buy back collection mechanisms is still very
popular in many parts of the western hemisphere. People are offered
money for aluminum cans that they collect and redeem at a recycling
center or reverse vending machine. Most locations buy the cans by weight
but some of the older systems pay for each can. Voluntary drop off
locations are still in use in much of the EEC, and in more rural parts
of the US. Many of these programs have been replaced by blue box
programs, where a number of household recyclables are picked up at the
curb and taken to large recycling facilities that sort and package the
items for sale.
Recyclers can process
aluminum cans in a number of ways. Small low volume processors will
normally flatten cans and sell them to a nearby wholesaler. Larger
operations will bale, densify or in some cases shred cans for shipment
to aluminum consumers. The aluminum companies have defined
specifications on how aluminum cans should be prepared.
How, exactly are the cans
recycled ? After collection and processing the aluminum UBC ( Used
Beverage Cans) are shipped by truck, railcar or sea container to
smelting plants. The bales of cans are unloaded and tested for quality
and moisture content. After inspection, the bales of cans are broken up
in a shredder into small pieces. These shredded cans are then conveyed
into a De-lacquering oven to remove the paint and residual moisture. The
hot shredded aluminum is then passed over a small screen to remove and
dirt and contaminants and fed directly into a reverbatory furnace.
Heated to 1400 degrees Fahrenheit ( 650 Centigrade) the cans melt and
blend in with the molten metal already in the furnace. A mixture of salt
and KFl are added as a flux to help separate out any oxides (dross) that
are skimmed off.
Molten aluminum is checked
for proper chemistry and then tapped ( removed) from the furnace and
poured into large molds that cast sheet ingots. These large rectangular
ingots ( 20 to 40,000 lbs each) are allowed to cool and harden. When
they are needed, the top and bottom surface of the sheet ingot ( alloy
3105) is milled to a smooth surface in a process called "Scalping". The
scalped ingot is then passed between two giant steel rollers in a large
rolling mill. The sheet is passed through a few more times until it is
about 1/2 an inch (1.25 Cm) thick and maybe 1000 feet (300 meters)long.
This long sheet is then annealed to soften it and passed to a series of
rollers in a finishing mill where it acquires the necessary hardness and
thickness. The edges are trimmed in a slitter and the coil is rolled up
for shipment to a can manufacturer. The finished coil may be 2 miles (3
kilometers)long and made from over 1.2 million recycled cans.
If not properly recycled, an aluminum can will still be on the surface
of the earth after 500 years. Aluminum recycling can reduce air
pollution by 95%. It can save 90% to 95% of the energy required to
manufacture aluminum from recycled aluminum cans than from aluminum
core.
If each person recycles one
aluminum can in each month, 1,750 to 3,500 gallons of gas can be saved

Tin cans
can be processed in bales or into high density bricks for direct
shipment into a steel mill. Material can be shipped via railcar, van
trailer, dump trailer, flatbed or in walking floor trailers. Like
aluminum, each mill has preferences on how they want material packaged
and delivered. It takes a fairly substantial baling press to make a
decent tin can bale. The product must be tight, especially if you are
shipping on a flatbed truck. We currently purchase tin cans in the east,
midwest and southern US and Canada. Let us know what you have available
and we will contact you with a price.
Tin can bundles are
relatively low in value and are seldom imported. The value to recyclers
depends mostly on the amount of freight it takes to reach a steel mill.
Recycling processors were paid between $30 and $80 a ton for baled tin
cans picked up at their facilities in 1998. Fortunately, this material
is abundant and easy to process so the handling costs are fairly low.
Because they are magnetic, they are sorted from other recylables
automatically with a magnetic conveyor belt. These belts usually feed
the steel directly into an automatic baling press which produce mill
quality 1000 to 2000 lb bales that are ready for shipment.
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