Effect of Grinding Environment on Galena Flotation

The generation of H 2 O 2 during the grinding of galena and its effect on the oxidation of galena particles leading to a decrease in flotation recovery has been studied.The influence of two types of grinding media in wet and dry grinding of galena on the formation of hydrogen peroxide and its flotation response was examined.Galena ground in mild steel grinding media generated more hydrogen peroxide compared to stainless steel media.Thus, lower flotation recovery of galena ground in mild steel could also be attributed due to the presence of higher amounts of H 2 O 2 in the pulp liquid, besides widely reported galvanic interactions between grinding medium and mineral.The extent of galena surface oxidation because of either galvanic interactions or H 2 O 2 presence or both, is not very clear.Clearly, both mechanisms operate in galena oxidation and needs further investigation to distinguish the predominant mechanism among the two or the extent of each contributing to surface oxidation.