How are different types of copper ore flotated?

Priority flotation

For disseminated copper-sulphide ores, a priority flotation process is employed, whereby copper is floated first, followed by sulphur flotation of the tailings. To reduce sulphuric acid consumption during sulphur flotation and ensure safe operation, process conditions with low alkalinity should be used as far as possible during copper flotation.

Mixed-separation flotation

This process is particularly advantageous for copper-sulphide ores with low sulphur content in the raw ore and where the copper minerals float readily. The copper-sulphide minerals are first subjected to mixed flotation in a weakly alkaline pulp; the mixed concentrate is then treated with lime in a highly alkaline pulp to separate the copper and sulphur.

Semi-Priority Mixed-Separation Flotation

Semi-priority mixed-separation flotation utilises highly selective collectors, such as aliphatic oils, in the semi-priority copper flotation stage to first float the easily floatable copper minerals, yielding a partial quantity of qualified copper concentrate. This is followed by mixed flotation of copper and sulphide minerals, with the resulting mixed copper-sulphide concentrate processed using a flotation process designed to float copper whilst suppressing sulphides. This method avoids the suppression of easily floatable copper minerals caused by high lime consumption and eliminates the need to consume large quantities of sulphuric acid to activate pyrite.