US EPA

2006448 

Journal Article 

PRE-FLOTATION LEACHING OF POLISH CARBONATE COPPER ORE 

Zarudzka, E 

2009 

43 

85-92 

WOS:000263907300008 

The copper ore deposit of LGOM (Legnica-Glogow Copper Basin) is located in the Foresudetic Monocline (SW Poland) and has a polymetallic character because of content of silver, lead, copper and accompanying metals such as cobalt, zinc, nickel, rhenium and gold. Over 110 metalliferous minerals were identified in the deposit. A sedimentary nature of the deposit results in necessity of fine grinding for effective liberation of sulfide particles prior to flotation. Fine dissemination of metalliferous minerals, particularly in the carbonate type ore, considerably reduces the susceptibility to effective liberation. A beneficial effect of non-oxidative leaching of carbonate gangue with sulfuric acid on copper ore flotation was presented in the paper. It was shown that the non-oxidative leaching of the flotation feed is a selective process leading to liberation of sulfide minerals disseminated in the gangue carbonate matrix. Acid leaching causes chemical decomposition of carbonate matter and releases fine grains of copper minerals. Kinetics of leaching of the investigated ore sample with various amounts of sulfuric acid were presented. It was shown that after decomposition of 70% of carbonates in the flotation feed, metal recovery and concentrate grade increased remarkable in comparison to the results observed for the unleached feed. The products of leaching contain solid hydrated calcium sulfate (gypsum), soluble magnesium sulfate and gaseous carbon dioxide. Carbon dioxide evolving during the reaction creates a non-oxidizing atmosphere in the pulp during leaching and therefore effectively prevents digestion of metals from sulfide minerals. The liberation of copper minerals due to leaching provides better separation of metallic ore components by flotation. 

leaching; flotation; carbonate copper