Estudo sobre a flotação de silicatos em coluna para o processo de concentração da apatita

Abstract

The phophate is an indispensable nutrient to the vegetable and therefore animal development, in Brazil, the mineral wich contains phosphate is the apatite. The progressive content reduction of the ore deposits already discovered and being explored, allied to the growing demand for food, turns imperative the phosphate ore processing in many ways of the processings, mainly in that it says respect to the decrease of contaminants minerals. The flotation process is the main technology applied for the concentrate the apatite mineral, which passed for constants developments in the last decades being distinguished the flotation columns to the improvements of the concentrates gotten and economy in the project investments. Because an increase of the siliceous concentration in the phosphate rock of the Barreiro deposits (Araxá-MG), the objective of this work is developing the flotation of siliceous in column for the process of concentration the apatite. In this context, to quantify the effect of the operational variables as well as of the dosage of reagents in the grade of SiO2 in the product of deep and the recovery of P2O5 in the concentrate, a time that the flotation of siliceous represents in a stage of purification of the ore. In view of the gotten results, a global statistics analysis and a canonic analysis were made in order to optimize the operational conditions. The use of the collector Flotigam EDA showed itself suitable for siliceous flotation in column for the apatite concentration process. The best result carried through the tests realized in this work was a concentrate of flotation with recuperation of 6 wt. % P2O5, and product with grade of 8.12 wt % SiO2. The excellent operational conditions in the explored band was: air flow between 40 e 60 L/h, washed water flow of 0,40 L/min, 0,39 L/min of recycle flow, collector dosage of 450 g/t, depressor dosage of 550 g/t and collector conditioning time of 10 min for 340 g of ore. The results obtained from the benches column had shown the possibility of siliceous flotation in a previous stage of the apatite flotation.