Mineral Metallurgy
Mineral metallurgy is a centuries-old field of study that deals with the transformation of metal ores into metal using a combination of physical, chemical and in some cases, biological processes. It combines science and engineering principles to extract, refine, and process base metal ores and to produce metals, alloys and metal products. Mineral metallurgists study and develop methods for creating superior properties and characteristics of metal that can better resist corrosion, enable fastener performance improvements, and extend the lifetime of metal parts in all types of environments. The field of metal production is constantly evolving, driven by improvements in technological advancements and innovations, as well as metal processing techniques.
Mineral metallurgy involves the use of various methods of metal production in two primary categories: pyrometallurgy, which is the use of high-temperature processes such as smelting and vacuum arc remelting; and hydrometallurgy, which is the use of chemical and physical processes such as hydrometallurgical extraction. Pyrometallurgy is used to process raw concentrate ores by reducing the oxide material to be smelted, or reducing ore particles that cannot be smelted. Hydrometallurgy is used to extract metals from ores that cannot be reduced in pyrometallurgical processes, such as those containing high concentrations of salts, organics, or heavy metals.
In mineral metallurgy, the most common type of process used is the sintering process, or the process of smelting ore particles together to form a solid mass. Sintering involves the use of primarily heat and pressure to reduce the particle size of ore and bind the smaller particles together into larger lumps or agglomerates. After being sintered, the ore is then melted into a liquid metal form and cast into different shapes. The process can also be used to produce metal alloys by introducing certain minerals into the furnace. Common metals used in sintering include aluminum, copper, brass, bronze, iron and steel.
Besides the sintering process, mineral metallurgy also employs other methods such as electrowinning and electrorefining for precious metals recovery. In electrowinning, metal is removed from ores via an electrochemical cell, while in electrorefining, impurities are removed from metals using an electrolytic cell.
Mineral metallurgy has evolved over the centuries and is still a subject of active investigation. Today, metallurgists are continuing to make advances in process technology and data analysis to develop innovative new methods that enhance the efficiency, cost effectiveness and safety of mineral processing and metal production. Looking ahead, its continued development will be essential for the continued success of the metals industry.
