Use of dispersants to optimize low content phosphatic ore flotation

Abstract The concentration of the igneous phosphatic ores is determined through froth flotation. However, the fine particles present in the pulps cause a decline in selectivity and metallurgical recovery because they can cover thick particles and increase the consumption of reagents. Therefore, the objective of this study is to evaluate dispersion during the desliming and bench flotation of low content phosphatic ores. Sodium hexametaphosphate, sodium silicate, DP-304A, and lauryl ether sulfate were tested as dispersants in a Denver mechanical cell. Saponified soybean oil was used as the collector and cassava starch was gelatinized as a depressant. Desliming combined with flotation, dispersion combined with desliming and flotation, and dispersion combined with flotation were evaluated. The optimal conditions for desliming and flotation were the use of sodium silicate at a dosage of 3000 g/t. Sodium silicate served as both a depressant and a dispersant. Statistical analysis showed that desliming with flotation increased the content and recovery of apatite. Dispersion resulted in decreased metallurgical loss during desliming and increased apatite recovery during flotation.