Filtragem de minérios de ferro - comparação entre métodos de filtragem de laboratório: teste de folha e funil de Büchner

Abstract

Once iron ores usually require wet processing methods, it is often necessary to remove most of the water added during the industrial operation. In this case, the finer the product the greater is the difficulty to remove water from filtration cake. These samples represent products of the industrial processing of MBR, the second largest Brazilian iron ore producer, with different size distributions and Blaine indices. The final removal of water from pellet feed fines is usually performed by means of rotary vertical disc filters (RVDF) and, more recently, also by horizontal belt filter at MBR. The filtration tests were performed following two different laboratory procedures. The results indicated significant influence of cake thickness and of the addition of reagents on cake moisture and on unit filtration rate. It was also observed that the industrial operation could be optimised taking into account these laboratory results. The evaluation of the laboratorial procedures (Leaf Test, Modified Leaf Test and Büchner Test) is the target of this work. The dewatering curves obtained under different cake thickness and considering the addition of flocculants and/or surfactants are d iscussed in this work.