Avaliação da troca do revestimento do moinho de bolas sobre a qualidade física do produto em uma usina de beneficiamento de bauxita no Nordeste do Pará

Abstract

Comminution is an operation in the minerals industry, and is notable for its high energy consumption. In this sense, proper operation of the equipment is essential to obtain the desired particle size without wasting energy. In the plant, the ball mill is widely used to promote particle size reduction and consequently mineral-ore liberation, in order to meet the concentration stages. In addition to the operating parameters of this equipment, attention must be paid to the wear of the internal lining. Some aspects of the lining, such as the height of the lifter, the A/B ratio, among others, play a significant role in the efficiency of the grinding process. The aim of this study was to evaluate bauxite granulometry and the efficiency of the operation, comparing the product obtained before and after replacing the ball mill lining. The results obtained showed a 16,84 % increase in grinding efficiency when compared to previous analyses, which also showed a significant change in the grain size of the 0,5 mm mesh. In addition, there was a thinning of the grain size curve of the milling product, caused by the change of lining. Thus, after changing the lining, gains were seen in the processing of the mineral, providing satisfactory results in the beneficiation plant.