Dissolution of Copper Sulfide Minerals from Fractured Ore Bodies.
Soc Min Eng AIME Oct 21-23 1970 Preprint 70-AS-329, 1970 Oct; :1-15
Leaching now yields about 15 percent of the nation's annual new copper production. About 220,000 tons of copper was made in 1969 by heap and vat leaching of ore, dump leaching of waste, and in-place leaching of caved underground workings. Although in-place leaching was practiced as long ago as the 15th century, it is little used and contributes only a few percent of the total leach copper production. Current technology in this area is exemplified by practice at the Miami, Arizona, mine of the Miami Copper Comapny. Despite its limited use, the concept of extracting copper by in-place leaching without physically mining and transporting the ore continues to present intriguing cost saving possibilities. Unfortunately, the bulk of the copper in deep ore deposits occurs as sulfide minerals that are not easily dissolved. On the assumption that fracturing of rock and solution injection and collection would be feasible, an assessment is made of solution systems that might be employed for the different copper sulfide minerals in porphyry ore bodies. These include the conventional ferric sulfate-sulfuric acid systems and combinations of sulfide mineral oxidants and different acids.
Soc. Min. Eng. AIME, Oct. 21-23, 1970, Preprint No. 70-AS-329, PP. 1-15