Optimization of flotation variables for the recovery of hematite particles from BHQ ore

Abstract

The technology for beneficiation of banded iron ores containing low iron value is a challenging task due to increasing demand of quality iron ore in India. A flotation process has been developed to treat one such ore, namely banded hematite quartzite (BHQ) containing 41.8wt% Fe and 41.5wt% SiO₂, by using oleic acid, methyl isobutyl carbinol (MIBC), and sodium silicate as the collector, frother, and dispersant, respectively. The relative effects of these variables have been evaluated in half-normal plots and Pareto charts using central composite rotatable design. A quadratic response model has been developed for both Fe grade and recovery and optimized within the experimental range. The optimum reagent dosages are found to be as follows: collector concentration of 243.58 g/t, dispersant concentration of 195.67 g/t, pH 8.69, and conditioning time of 4.8 min to achieve the maximum Fe grade of 64.25% with 67.33% recovery. The predictions of the model with regard to iron grade and recovery are in good agreement with the experimental results.

Keywords

hematite / iron ore treatment / flotation / metal recovery / design of experiments / mathematical models / optimization

References

[1] Ma X, Marques M, Gontijo C. Comparative studies of reverse cationic/anionic flotation of Vale iron ore. Int. J. Miner. Process., 2011, 100, 179.

[2] Rocha L, Cançado RZL, Peres AEC. Iron ore slimes flotation. Miner. Eng., 2010, 23, 842.

[3] Quast K. Flotation of hematite using C6-C18 saturated fatty acids. Miner. Eng., 2006, 19, 582.

[4] Montes-Sotomayor S, Houot R, Kongolo M. Flotation of silicated gangue iron ores: mechanism and effect of starch. Miner. Eng., 1998, 11, 71.

[5] Turrer HDG, Peres AEC. Investigation on alternative depressants for iron ore flotation. Miner. Eng, 2010, 23, 1066.

[6] Araujo AC, Viana PRM, Peres AEC. Reagents in iron ores flotation. Miner. Eng., 2005, 18, 219.

[7] Li L, Liu JT, Wang YT, Cao YJ, Zhang HJ, Yu HS. Experimental research on anionic reverse flotation of hematite with a flotation column. Procedia Earth Planet. Sci., 2009, 1, 791.

[8] Shen HT, Huang XY. A review of technical progress in iron ore processing (2000–2004). Min. Metall. Eng, 2005, 25, 26.

[9] Zhang GQ, Li WB, Bai XM. Research and practice of technological flowsheet of Qidashan iron mine. Met. Mine, 2006 37.

[10] Wang YH, Ren J W. The flotation of quartz from iron minerals with a combined quaternary ammonium salt. Int. J. Miner. Process., 2005, 77, 116.

[11] Pradip M. Processing of alumina-rich Indian iron ore slimes. Int. J. Miner. Met. Mater. Eng., 2006, 59, 551.

[12] Das B, Mishra BK, Prakash S, Das SK, Reddy PSR, Angadi SI. Magnetic and flotation studies of banded hematite quartzite (BHQ) ore for the production of pellet grade concentrate. Int. J. Miner. Metall. Mater., 2010, 17, 675.

[13] Raj B, Rao BSS, Chandra S. Development of a process flow sheet for beneficiation of Indian banded hematite quartz (BHQ) iron ore. Proceedings of Iron Ore Conference, 2007 375.

[14] Lazic ZR. Design of Experiments in Chemical Engineering, 2004, Weinheim, Wiley-VCH

[15] Box GEP, Wilson KB. On the experimental attainment of optimum conditions. J. R. Stat. Soc. Ser. B, 1951, 13, 1.

[16] Box GEP, Hunter JS. Multi-factor experimental designs for exploring response surfaces. Ann. Math. Stat., 1957, 28, 195.

[17] Kwak JS. Application of Taguchi and response surface methodologies for geometric error in surface grinding process. Int. J. Mach. Tools Manuf., 2005, 45, 327.

[18] Gunaraj V, Murugan N. Application of response surface methodology for predicting weld bead quality in submerged arc welding of pipes. J. Mater. Process. Technol., 1999, 88, 266.

[19] Aslan N. Application of response surface methodology and central composite rotatable design for modeling and optimization of a multi-gravity separator for chromite concentration. Powder Technol., 2008, 185, 80.

[20] Naik PK, Reddy PSR, Mishra VN. Optimization of coal flotation using statistical technique. Fuel Process. Technol., 2004, 85, 1473.

[21] Martínez-L A, Uribe S A, Carrillo P FR, Coreño A J, Ortiz JC. Study of celestite flotation efficiency using sodium dodecyl sulfonate collector: factorial experiment and statistical analysis of data. Int. J. Miner. Process., 2003, 70, 83.

[22] Kelebek S, Khan A, Wall B, Pettingil J. Statistical evaluation of the effect of polyamine type in flotation of a Ni-Cu complex sulphide ore. Proceedings of XXIII International Mineral Process Congress, 2006 1830.

[23] Sheridan MS, Nagaraj DR, Fornasiero D, Ralston J. The use of a factorial experimental design to study collector properties of N-allyl-O-alkyl thionocarbamate collector in the flotation of a copper ore. Miner. Eng., 2002, 15, 333.

[24] Mehrabani JV, Noaparast M, Mousavi SM, Dehghan R, Ghorbani A. Process optimization and modelling of sphalerite flotation from a low-grade Zn-Pb ore using response surface methodology. Sep. Purif. Technol., 2010, 72, 242.

[25] Kulkarni RD, Somasundaran P. Kinetics of oleate adsorption at the liquid/air interface and its role in hematite flotation. AIChE Symp. Ser., 1975, 71(150): 124.