The Harmonious Design on the Beneficiability of the Pt-Pd Ores Containing High-MgO Gangues in Yunnan

摘要

Flotation characteristics of the fine-disseminated copper-nickel sulfides containing Pt and Pd and thermodynamic properties of high amounts of serpentine gangues by diluted acidic leaching in the ore sample of Yunnan were investigated by bench flotation tests and acidic leaching tests and their combination tests have also been conducted to exploit the harmonious design to extract all the values from the ore sample. Based on the results of bench flotation tests, it has been suggested that traditional flotation with the target of only metallic values in the ore was not available and profitable due to the fact that it was inevitable of the deteriorated dilution of serpentines in the flotation concentration using common various kinds of flocculants or depressants, in which the content of MgO in the concentrate was around 20.0%, while leaching tests by waste acids from producing TiO_2 indicated that this may be a promising method to extract MgO andα-Fe_2O_3 from the ore sample, since it can weaken the disturbance of serpentines significantly and lead a satisfied results of the Cu-Ni sulfide flotation. In this study, a harmonious flow-sheet, which involves leaching by waste acids and traditional flotation process, had been designed with the objective of extracting the metallic values and two non-metallic products, which includes α-Fe_2O_3 and MgO, from the ore sample. It is worthy noticed that the acidic waste liquids from a TiO_2 company in Panzihua was used as leaching agent, which can dissolve 98.81% Mg~(2+) and 78.43% Fen+ with little Ni~(2+) and Cu~(2+). By the comparison of the flotation results and benefits between traditional flotation alone and harmonious design, besides the two more qualified non-metallic products, α-Fe_2O_3 and MgO, a better concentrate containing a grade of only 2.64% MgO at the grades of 2.58% Cu, 2.97% Ni and 81.02 g/t Pt+Pd with the recoveries of 93.79% Cu, 83.14% Ni and 79.19% Pt+Pd respectively, were harvested from the harmonious design.