Per: renata monteiro furtado (CBMM), arthur pinto chaves (universidade de são paulo), francisco gregianin testa (cbmm), priscila tavares de paula (cbmm), andré soares braga (basf)
Abstract:
The conventional way to carry out the disposal of tailings is in dams with dilute slurries is intensively discussed today. Successive accidents in recent years have shown the shortcomings of this practice. An alternative is the use of high-density slurries. It can eliminate particle size segregation into the dam reservoir, improve life cycle, water recovery and render possible safety gains. To obtain high-density slurries they must be dewatered with thickeners, for example. This study is aimed to verify thickening optimized parameters for niobium ore flotation fine tailings. Physical, chemical and mineralogical characterization were performed, and batch thickening tests were carried out with different solids content in feed, pH, flocculant type, concentration and dosage. The results of settling rate, overflow turbidity, and solids content in underflow indicated best conditions are 5% of solids in feed, flocculant concentration of 0.05%, Magnafloc® 1011 flocculant (anionic polyacrylamide) addition of 60 g/t and pH 5.4. It was obtained 41% solids in underflow with 125 NTU of turbidity in the supernatant liquid and 52x10-3 m/s of settling rate.