Upgrading Technologies
By Turra Ossau
Brazil, in the last years, has improved its technology on diminishing pollution emissions.
For example, today, São Paulo has the one of the biggest aluminium recycling plant. It
recycles almost 85% of all the aluminium cans used for beverages like soda and beer. The
process starts by removing the ink of the cans’ surfaces. Then they are melt and sent to
factories to be reused. Another big trend in São Paulo’s recycling is methane. Most of the
organic rubbish is sent to big recycling plants where they are decomposed and turned into
methane gas, which is sent to thermal energy plants, where it is burnt and used to generate
energy for the city. Not only aluminium is recycled. Steel is also recycled, at COSIPA, the
second biggest steel recycling plant in the world. There, scrap metal is melt to produce
steel. Cars, trains, boats and even buildings’ guts are melt at about a third the Sun’s surface
temperature and separated from impurities. As the steel follows through its way, the
impurities can be used to generate energy and/or improve plantations.
But São Paulo is known for its most known invention. The Tetra-Pak carton. It is made of a
combination of six layers of aluminium, to prevent oxygen and light to get into the carton,
plastic, to make it impermeable and cardboard, to make it
resistant. However, as they are made, the layers cannot be
separated anymore. The scientists have split apart the atom, but for
years, no one could split apart the Tetra-Pak layers. Until now.
São Paulo has the first Tetra-Pak recycling plant, in which TetraPak cartons are shredded to produce recycled paper. By using
Tetra-Pak fibres in recycled paper, it will end being much more
resistant, than normal recycled paper. The remaining parts of the
carton, which are aluminium and plastic, are separated in a plasma
jet, about thrice the Sun’s temperature. The molten aluminium
settles down and the plastic floats. The aluminium, which is 99%
pure, will be reused to make cans and Tetra-Pak, and the plastic
will be transformed in wax, to be used in production of candles.
Not only products can be recycled. Cubatão, at the outskirts of the city, is an industrial
complex. Before 1990, it was considered the most polluted place in the world. However
after 1990, São Paulo’s government decided to order the industries to reduce all their
pollution emissions. Nowadays, for each piece of equipment in any industry at Cubatão,
there’s another one that neutralizes or reduces the pollution emitted.
April 1st 2007
Practicising for C.A.E. test.
Paper based on documentary “Metropolis” from National Geographic Channel.