The leaching process is a hydrometallurgical technique, which consists of obtaining copper found in oxidized minerals, which are separated through the application of a solution of sulfuric acid and water. This technique is used to recover uranium, copper, zinc, nickel, cobalt, among others. Pile and dump leaching consists of extracting metals by passing a solution through a pile of ore. The leaching solution reacts chemically with the ore, dissolving the metals and removing them from the mineralized rock, producing a “rich” solution.
The material used to form the leaching piles previously goes through different processes, the first one corresponds to the fragmentation of the ore, which is carried out in primary and secondary crushers, to then be transported by conveyor belts to the location of the pile. Finally, it crosses the irrigation system, which by means of sprinklers and drippers pours the acid solution. It should be noted that the ROM piles correspond to ore without crushing.
One of the most important aspects of this process is the stability of the piles, which is closely related to their height. In the case of copper, silver and gold leaching piles, they have a final height between 30 and 60 meters. Another relevant aspect is the angle which is determined during the design to maintain slope stability.