Effect of curing time on the dissolution of a secondary copper sulphide ore using alternative water resources

In the north of Chile, due to water shortages, the depletion of oxide ores and the abundance of chalcopyrite ore, mining industry is searching for sustainable hydrometallurgy processes that can use alternative water resources. The leaching process must enhance the dissolution of copper sulphide ore that are refractory to conventional leaching. This paper reports a study on the effect of addition of chloride ion using seawater and discard brine in the agglomeration stage of a secondary copper sulphide ore. The effect of curing time on the same ore also is reported. The leaching tests have been carried out in column irrigated with raffinate under ambient conditions. A size distribution with a P80 of 17 mm is used. A maximum of 72% of copper extraction is obtained using discard brine and 68% using seawater. The use of discard brine and seawater are favorable in all the tests performed. Through an Analysis of Variance (ANOVA), it is determined that the curing time has the highest contribution (92.37%) on the percentage of copper extraction.