Caracterização e valorização de placas de circuito impresso de aparelhos smartphones

Abstract

The cell phones are the electronics that have become the most frequent in Brazilian homes in recent years, especially smartphones, offering several benefits to users in the field of telecommunications. As a consequence also has been growing the amount of cell phones discarded in a lower range of time due to the advancement of technology. Cell phones contain several heavy metals that can cause environmental impacts due to your inappropriate disposal. On the other hand, there are elements such as copper, iron, aluminum and others can be recycled. Thus, the aim of this study was to characterize smartphones devices and employ mechanical processing (through milling, grinding, magnetic and electrostatic separation) on printed circuit boards (PCBs) in order to concentrate metals, especially copper, identifying the key elements obtained by means of the processes employed. There were collected, removed manually and weighed 87 smartphones devices that consist of housing (31 %), display (30 %), battery (20 %), PCB (16 %) and other (3 %). PCBs were comminuted in knife mill and separated into 4 size ranges (F1, F2, F3 and F4). After characterization of 4 granulometric fractions it was observed medium quantities of copper (35 %), silicon (11 %), aluminum (5 %), iron (3 %) aluminum (5 %), iron (3 %), nickel (3 %), tin (3 %) and other in smaller quantities, varying according to the particle size. The PCBs were subjected to magnetic separation, by which was obtained in magnetic fraction 9-34 % of iron, increasing the concentration depending on the size of particle size, plus 3-11 % of nickel. The non-magnetic materials, in order to concentrate copper, passed through electrostatic separation process. Electrostatic separation generated conductive fractions concentrating up to 52 % of copper, decreasing the concentration as the particle size increases.