The Franke open pit mine is located in the Atacama Desert in the Taltal region of Chile, in the southern part of the Antofagasta region, which is the largest Chilean copper basin. The mine is located at an altitude of approximately 1730 meters above sea level.
Copper ore extraction from the Franke deposit has an almost 100-year history. Initially, the ore was extracted by independent miners called “pirquineros”, and for years they carried out uncontrolled ore extraction from surface deposits. In the second half of the previous century, the deposit was explored by many companies, but mining did not commence until 2009.
Extraction of copper ore from the Franke mine is carried out using conventional methods typical for open pit mines, i.e. blasting and transporting the ore with haul trucks.
The production of copper in the Franke mine is based on the solvent extraction and electrowinning (SX/EW) method which involves subjecting the ore to sulphuric acid. The pregnant leach solution (PLS) is pumped out of the heap and after the initial mechanical cleaning is subjected to the SX process, followed by the EW electrowinning process. The final products are copper cathodes.