Combined blasting–reagent effect on extraction of valuable components from model material

The possibility of application of blasting in the processes of preliminary enrichment and oxidative preparation is studied. The influence of a combination of reagent and blasting on a model material simulating rock mass is examined. The model material is a cement–sand mixture with metallic copper powder evenly dispersed in it. The copper content in the model material is 0.3 %. After explosive fracture in combination with the reagent impact, the model material is subjected to leaching. The effect of the blasting and reagent combination was evaluated by the copper content in the pregnant leaching solution. The reagents used in the blasting–reagent combination were distilled water, an activated hydrocarbonate–peroxide solution (NaHCO3*+H2O2), an active hypochlorite–chloride solution (Cl*) and an alkaline–peroxide solution (NaOH*+H2O2). The combination of blasting and reagent impact on the model material had a positive effect on the growth of copper content in the pregnant solution in leaching in all experiments (compared to regular blasting treatment). The increase in the copper concentration was 50.34–83.2%, depending on a reagent used, and for the active hypochlorite–chloride solution, the minimum copper concentration was 3.4 %. The effect of electrochemical activation of the leaching solution on the concentration of copper in the pregnant solution was also studied. In two experiments (combined blasting and reagent impact on the model material with active chloride and alkaline–peroxide solutions), the activation of the leaching solution reduced the time for the copper leaching process to reach a plateau from 2 hours to 44 minutes. The maximum achieved copper concentrations in the pregnant solution in most cases are associated with the combined blast and reagent effect on the model rock mass, as well as with the activation of the leaching solution.The chemical analysis and technological study were carried out at the Shared-Use Mineral Research Center of the Khabarovsk Federal Research Center, Far Eastern Branch, Russian Academy of Sciences.