Efeito dos parâmetros de processo na potência de moinhos verticais

Abstract

The Minas-Rio regrind circuit is the largest vertical milling plant in the world today. It was designed with sixteen equipment of 1,500 HP each to process 24.5 million tons of Pellet Feed concentrated by reverse flotation of iron ore and adjust this material for transportation via pipeline. This process step is crucial for production system performance as low productivity can cause upstream production constraints or failure to meet safety specifications of the product's transport. Thus, the objective of this work was to study the main variables that influence the vertical grinding process and to evaluate their impact on the equipment productivity. To carry out this study, laboratory grind tests and industrial samplings were done throughout the life of the mill liners. With these data it was possible to define the effects of the liners, the slurry density, the grinding media and the height of the media charge. In the last stage of the work was built a mathematical model to predict the power of the mills and thus, give subsidies to define the best operational strategy of the system.