The Production Process of Copper

Copper, one of the earliest metals used by humans, plays an indispensable role in modern industries, construction, electronics, and other fields. From copper ore hidden deep underground to various refined copper products, its production process embodies sophisticated craftsmanship and technology.

The production of copper begins with mining. Open-pit mining and underground mining are the two main methods. The former is suitable for ore veins with large reserves and shallow burial, while the latter is used for mining ore bodies buried deeper. The mined copper ore has a low copper content and needs to go through pretreatment processes such as crushing and grinding to reduce its particle size for subsequent ore dressing.

Ore dressing is a crucial step in increasing the grade of copper ore. Through the flotation method, by taking advantage of the differences in the physical and chemical properties of mineral surfaces and adding specific reagents, copper minerals adhere to bubbles, thus separating from gangue minerals to obtain copper concentrate.

Copper concentrate enters the smelting stage, and there are mainly two methods: pyrometallurgy and hydrometallurgy. In pyrometallurgy, copper concentrate is first roasted to remove part of the sulfur and moisture, and then smelted to produce matte. The matte is converted to obtain blister copper, which generally has a purity of about 98% and requires further refining. Hydrometallurgy, on the other hand, uses solvents to leach copper from copper concentrate, and then obtains electrolytic copper through processes such as extraction and electrowinning.

Refining is the final step in producing high-purity copper. Pyrometallurgical refining removes impurities in blister copper through oxidation-reduction reactions. Electrolytic refining uses blister copper as the anode and pure copper sheets as the cathode, and conducts electrolysis in a copper sulfate solution, allowing copper ions to precipitate on the cathode, ultimately obtaining electrolytic copper with a purity of over 99.95%.

From the mine to the refinery, every step reflects human wisdom and technology, ensuring that copper, an important metal, meets the needs of various industries around the world in high-quality forms.