1. Copper Mining: Extracting Ores
Copper is a precious metal embedded deep within the crust of the earth, and its extraction involves arduous mining activities. The entire process commences at open-pit or underground mines, which are loaded with sulfide and oxide ores. Employees at these copper mines utilize large machines to extract these ores and transport them onto trucks or conveyors for processing purposes. Note that companies prefer sulfide ores as they are richer in copper content compared to oxide ores.
2. Conversion of Copper Ores into Concentrates
Upon extraction from the mines, the copper ores progress to the next phase of refining where they are converted into concentrates. This is executed through a process known as froth flotation. Here, the crushed ores are mixed with water to form a slurry. Further, the processing entails the addition of chemicals, such as pine oil, to the slurry, causing the copper-bearing particles to detach from waste material and adhere to air bubbles. Upon floating to the surface, these ‘froths’ can be skimmed off resulting in concentrates containing about 25-35% copper.
3. Copper Smelting: From Concentrates to Matte
The concentrates are then taken through a smelting process where they are heated intensely. This process yields molten copper that contains 60% copper and 30% iron. This liquid mixture, known as copper matte, also includes sulfur and precious metals such as gold and silver.
4. Converting of Copper Matte into Blister Copper
The copper matte then proceeds to the conversion phase, which involves blowing air into the matte under high temperatures. The oxygen combines with iron to create iron oxide that can be easily slagged off. This process results in blister copper, which is about 98% to 99% pure.
5. Electrorefining: Attaining Refined Copper
The final refining step is electrorefining. Here, a copper anode is dissolved in an electrolytic solution, leaving the impurities to settle at the bottom as anode sludge. Pure copper is then deposited on the cathode by an electrolysation process. The resultant copper cathodes are 99.99% pure and ready for use in a wide range of industries.
6. Copper Futures: Ensuring Continuous Trade
After refining, the copper market operates through futures contracts which are exchange-traded derivatives. These contracts allow copper producers to manage their price risk and provide a basis for pricing physical supply contracts for cathode producers, scrap dealers, and consumers.
7. Copper Recycling: A Sustainable Practice
Lastly, it is essential to mention the role of recycling in the copper industry. Given the finite amount of copper in the earth’s crust, recycling is a sustainable practice that can provide a sizable percentage of global copper demand. Notable is that recycled copper is just as potent as newly extracted copper, making it a valuable resource for several industries.
In conclusion, copper refining is a far-reaching and intricate process that involves several stages, each with its significance. However, it is critical to the production of copper that has significantly impacted numerous sectors globally, from telecommunications and construction to electrical engineering and beyond.
