O ciclo de vida do alumínio

Abstract

Aluminum is widely used for the industry of many ways. The major use of this material is due to the fact of its versatility and excellent performance in most applica-tions, besides its ability to be recycled indefinitely without losing its properties. In 2010, the aluminum world production was 40,800 millions of tons. The United States of Amer-ica (USA) was the 5° bigger producer with 1,726 millions of tons and Brazil the 7° with 1,536 millions of tons. With the increasing domestic aluminum use, consumption in Brazil is expected to triple by 2025. One of the major challenges for aluminum produc-tion is the high levels of energy consumption and its high cost; this input comes to represent almost half of spending on the transformation of aluminum. In this paper, we performed a comparative study between the energy matrix used in the US and the one used in Brazil to produce 1 kg of aluminum, consisting in 52% of primary aluminum from the bauxite mining, and 48% of secondary aluminum from recycling. The objective of this thesis is to evaluate the different potential environmental impacts caused by the production of aluminum considering the Brazilian energy matrix and the US energy matrix, as well as the different contributions in emissions of primary and secondary aluminum. The data from aluminum production and energy consumption were obtained from the data base Ecoinvent v.3. In The aluminum production inventory, the energy matrix was changed from the one used in the US to the one used in Brazil. The poten-tial impacts were calculated using the impact assessment method ReCiPe (I). The soft-ware Microsoft Excel was used to tabulate and present the results. The data normali-zation showed that among the 18 categories of impact, initially studied, only 11 were statistically significant. From these 11 categories, the US energy matrix had higher values of emissions in 7 of them, however despite the great difference between the energy matrices, the substances and the processes of higher impact were the same for both matrices, showing that the change did not exert great influence on the emis-sions values. Furthermore, the secondary aluminum has shown more efficient in terms of emissions compared to the primary aluminum.