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Vanalco is in the business of smelting aluminum. In 1987,
Vanalco purchased its smelting facility from ALCOA, which had
begun operations at this facility in 1940. The basic elements
required to make aluminum are alumina, electrical energy, and
carbon. The chemical process involved in the production of
aluminum is electrolysis.
In the smelting process, large buckets carried by overhead
cranes bring alumina to hoppers positioned on top of reduction
cells (cells). The hoppers feed the alumina into the center of
each cell where it is dissolved in a bath of a molten cryolite
solution (bath). An anode, which is a cubical carbon block
attached to a copper rod, is introduced into the cell, and
electrical current is passed from the anode, through the alumina-
cryolite solution, and into a cathode. Cathodes are carbon
blocks that line the bottom of the cell. The electrical current
flows out of the cathode through embedded steel collector bars,
then through a riser and into the anode in the next cell. The
electrical current reduces the alumina to aluminum and oxygen,
and this process produces aluminum continuously. Every other day
the molten metal is removed from the cells and transferred to a
casting area called the ingot plant (the plant). In the plant,
the molten metal may be either poured into molds directly and
allowed to solidify or combined with other alloys and cast into
pig or log shapes.
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Last modified: May 25, 2011