Comparative Study of Approaches based on the Taguchi and ANOVA for Optimising the Leaching of Copper–Cobalt Flotation Tailings

Abstract

Approaches based on Taguchi and analysis of variance (ANOVA) methods have been proposed for studying the leaching of copper–cobalt flotation tailings. Taguchi method was used to determine the optimum leaching conditions as well the most influential operating parameters. ANOVA was used to determine the relationship between the experimental conditions and yield levels, as well as to define the significances of parameters on the leaching yields. An L₂₅(5⁵) orthogonal array experimental plan was used to assess the effects of initial acidity (25, 50 , 75, 100, and 125 g/L), leaching time (30, 60, 90, 120, and 150 min), temperature (25, 35, 45, 55, and 65°C), pulp density (S/L = 10, 15, 20, 25, and 30 solid percent), and ferrous iron concentration (0.0, 1.0, 2.5, 5.0, and 7.5 g/L) on individual dissolution of Cu and Co. Under the optimum conditions (50 g/L, 60 min, 45°C, 15%, 2.5 g/L for Cu; and 100 g/L, 60 min, 65°C, 15% and 2.5 g/L for Co), leaching yields were 95.98% Cu and 97.74% Co. pH and Fe²⁺ were found to be key influential parameters of Cu and Co, respectively.

Keywords:

• ANOVA
• Cobalt
• Copper
• Flotation
• Leaching
• Taguchi
• Tailings