COPPER: SHAPING THE FUTURE OF THE GREEN ENERGY TRANSITION
Copper
Copper​
Copper ore is a naturally occurring mineral containing copper that can be economically extracted. The most common types of ores are Copper Sulfide Ore and Copper Oxide Ore. Differrent processes are used to extract copper from the respective ores to produce Copper Concentrates.
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Copper Concentrates​
Copper concentrates are used as raw material by smelters to produce the resultant metal which is widely used in various industries becuse of its high electrical and heat conductivity, malleability, ability to form alloys with other metals, and resistance to corrosion.
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Copper Concentrates
Specifications
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Feedstock: Copper sulphide & Oxide ore (average grade 5% Cu).
Primary mineral: Chalcopyrite (CuFeSâ‚‚), Chalcocite (Cuâ‚‚S), Bornite (Cuâ‚…FeSâ‚„) & Cuprite (Cuâ‚‚O)
Final Product: Copper concentrate (average grade 30% Cu).
Moisture Content: 8% (by weight).
Granulometry: 80% passing 200 mesh (75 microns).
HS Code: 2603.00.00
Production Processes for Copper Concentrates
Processing of Sulfide Copper Ores
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Crushing and Grinding: Sulfide ores are crushed and ground into fine particles to liberate the copper minerals from the surrounding material.
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Froth Flotation: The ground ore is mixed with water and specific reagents to create a slurry. When air is introduced, copper-rich minerals attach to bubbles and float to the surface, forming a froth that is skimmed off, producing a concentrate typically containing 20-30% copper.
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Thickening and Filtration: The concentrate is thickened and filtered to remove excess water, resulting in a solid material ready for smelting.
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Smelting and Refining: The dried concentrate undergoes smelting in a furnace, where it is heated to high temperatures in the presence of a flux to separate the metal from slag. The resulting product, known as matte, contains a higher concentration of copper. This matte is further refined through converting and electrorefining processes to achieve 99.99% pure copper.
Processing of Oxide Copper Ores
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Copper oxide ores: Cuprite (Cuâ‚‚O) ores are directly leached with sulfuric acid to produce copper sulfate solutions for electrowinning. Copper oxide ores, including cuprite, tenorite, malachite, azurite, and chrysocolla, are not typically processed into standard copper concentrates but remain essential resources for hydrometallurgical copper extraction.
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Heap Leaching: Crushed oxide ores are stacked on leaching pads and irrigated with a weak acid solution, typically sulfuric acid. This solution percolates through the heap, dissolving the copper minerals into a pregnant leach solution (PLS).
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Solvent Extraction (SX): The PLS is collected and mixed with an organic solvent that selectively binds with copper ions. This process separates the copper from impurities, resulting in a concentrated and purified solution.
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Electrowinning (EW): The purified solution is subjected to an electrical current in an electrowinning cell, causing pure copper metal to deposit onto cathodes. These copper cathodes are then harvested for further processing or sale.
