Copper occurs in two different mineral groups: sulfide ores, oxide ores (carbonate minerals and silicate minerals), and both ore types can be economically mined. Copper sulfide ores are the most profitable types of ores as they have high copper content, and the copper can more easily be separated from the unwanted minerals.
The most common source of copper sulfide ore is chalcopyrite, which accounts for about 50 percent of copper production. Chalcopyrite mainly consists of three types of elements: Cu, Fe and S. Most of the copper ores contains only 0.4%-0.6% copper and other valuable metals (as coproducts or byproducts), including molybdenum, silver, gold, bismuth, cadmium, and cobalt.
For many sulfide copper minerals, the removal of copper is ultimately accomplished with fire, so it is known as a pyrometallurgical process. In this process, ore is processed and then melted at a temperature of more than 2000 degrees.
Copper ore must be blasted with explosives to break it into manageable sized pieces. Then the ore is conveyed to a crusher in which it is reduced to rocks that average 8 inches in diameter-about the size of a football. Normally, copper mining plants crush the rocks even smaller for the next process.
Belts conveyors carry the ore from crushers to mills. The ore is mixed with water as it enters the mills and is crushed into very small pieces, becoming slurry. The copper particles have been broken out of the rock.
As the mill rotates, inner surface of the mill is bumped and collided against the hard rock with sharp angles, so the mill should be lined with wear-resistant material to prolong its service life. Naipu is a professional manufacturer for rubber liners used on copper mining mills. Its rubber & composite liners and rubber trammel screens are preferred choice for many mining plants.
The slurry then flows into the flotation machine with added reagents (collector and frother) and flows out as a mixture of copper and other metals called copper concentrate (approximately 30% copper).
Then, after smelting and refining, a cathode containing 99.98% pure copper is produced.