Aluminum is produced through the electrolysis of alumina, obtained from bauxite ore. Approximately, 4 tons of bauxite are necessary to produce 1 ton of aluminum, which is enough to produce 60 thousand cans of 33cl. Aluminum production demands large amounts of energy: to obtain 1 ton, you need about 16 thousand kilowatts and the equivalent to 1,7 ton of petrol. The use of recovered waste might save up to 95% of the energy, not considering the energy spent in collecting and sorting out the materials. The use of aluminum for containers presents obvious positive points when it comes to weight, which influences the amount of energy spent in transportation. The comparison to other kinds of containers, however, is the subject of various discussions since the appreciation of all variables is extremely complicated. The European Aluminum Association formed an Aluminum and Echology Group to study and clarify some questions, analysing the complete cycle of the material in all products in whose composition it is present, from beer cans to automobiles. The results, however, will only be known after some time dut to the difficulty of colletcing data and developing a methodology suitable to this evaluation. Also from an environmental point of view, it is hard to assess the impact resulting from the use of aluminum. Just to give an idea of the range of analysis on this subject, let’s examine the following cases: the manufacture of a 33cl. beer can in England, using cast aluminum in Norway with hydrelectric power and laminated in Germany afterwards, will produce 110 grams of CO2 (that equals 6,4 tons of CO2 per ton of aluminum). But, if the same can were produced in Germany, with energy obtained from the burning of coal, the amount of CO2 produced will be 280 gramas. This value can be even higher if the can were to be made in the Tzchec Republic, with lower-quality coal
Fonte: | Warmer Bulletin - World Resource Foundation |
Autor: | José Penido |
Email do Autor: | jpenido@resol.com.br |