Application of Response Surface Methodology for Optimization of Vat Leaching Parameters in Small Scale Mines: Case Study of Tanzania
In this work, the Response Surface Methodology (RSM) was used to study and optimize the vat leaching operating parameters namely as cyanide concentration, slurry pH and particle size. The experimental design was performed with aid of Minitab (version 16) statistical software. The Central Composite Design (CCD) was used to model and analyse the effect of the operating parameters. According to a quadratic model, the optimal conditions for highest gold leach recovery of 83% were found by a cyanide concentration of 950 ppm, slurry pH of 10.5 and particle size of 240 µm. The results are much significant compared with the current gold recovery of between 60 to 70%. The samples were collected at Nyarugusu small scale mines (Geita, Tanzania).
RSM, Vat Leaching, CCD, Optimization, Nyarugusu Small Scale Mines
J. Marsden and I. House, The Chemistry of Gold Extraction, West Sussex, England: Ellis Horwood, 1992.
La Brooy, S.R., Linge, H.G. and Walker, G.S. (1994) Review of Gold Extraction from Ores. Minerals Engineering, 7, 1213-1241. http://dx.doi.org/10.1016/0892-6875(94)90114-7
Rubisov, D.H., Papengelakis, V.G. and Kondos, P.D. (1996) Fundamental Kinetic Models for Gold Ore Cyanide Leaching. Canadian Metallurgical Quarterly, 35, 353-361. http://dx.doi.org/10.1179/cmq.1922.214.171.1243
Adams, M.D. (2005) Advances in Gold Ore Processing, Developments in Mineral Processing. Elsevier, Amsterdam
Chryssoulis, S.L. and McMullen, J. (2005) Mineralogical Investigation of Gold Ores. In: Adams, M.D., Ed., Advances in Gold Ore Processing, Elsevier, The Netherlands, 21-71. http://dx.doi.org/10.1016/S0167-4528(05)15002-9
Chen, T., Cabri, J. and Dutrizac, E. (2002) Characterizing Gold in Refractory Sulfide Gold Ores and Residues. Journal of Minerals, Metallurgy and Materials, 54, 20-22.
P. Ling, V.G. Papangelakis and S.A. Argyropoulos, An Improved Rate Equation for Cyanidation of a Gold Ore. Can. Metall. Q., 35(1996), No 3, pp. 225-234
P.D. Kondos, G. Deschênes, and R.M. Morrison, Process Optimization Studies in Gold Cyanidation, Hydrometallurgy, 3 (1995), pp. 235-250.
G. Deschênes and G. Wallingford, Effect of Oxygen and Lead Nitrate on the Cyanidation of a Sulphide Bearing Gold Ore. Miner. Eng., 8(1995), pp. 923-931.
G. Deschênes and P.J.H. Prud’homme, Cyanidation of Copper-Gold Ore. Int. J. Miner. Process, 50(1997), pp. 127-141.
Ogundare, O.D., Adeoye, M.O., Adetunji, A.R. and Adewoye, O.O. (2014) Beneficiation and Characterization of Gold from Itagunmodi Gold Ore by Cyanidation. Journal of Minerals and Materials Characterization and Engineering, 2, 300-307. http://dx.doi.org/10.4236/jmmce.2014.24035
S. Ellis, and G. Senanayake, The Effects of Dissolved Oxygen and Cyanide Dosage on Gold Extraction from a Pyrrhotite-Rich Ore. Hydrometallurgy, 72(2004), pp. 39-50.
L.R.P. De Andrade Lima and D. Hodouin, A Lumped Kinetic Model for Gold Ore Cyanidation. Hydrometallurgy, 79(2005), pp. 121-137.
X. Dai and M.I Jeffrey, The Effect of Sulfide Minerals on the Leaching of Gold in Aerated Cyanide Solutions. Hydrometallurgy, 8 (2006), pp. 118-125
M. M. Aghamirian and W.T. Yen, Study of gold of gold anodic behavior in the presence of various ions and sulfide mineral in cyanide solution. Miner. Eng., 18(2005), pg 89-102.