Valves for copper concentrates production, smelting and electrolysis
Selecting the right valves for copper concentrates production, smelting and electrolysis processes
Increasing the efficiency of copper concentrates production, smelting and electrolysis is possible by carefully selecting the optimal valves for each process. The most common copper ore types, copper oxide and copper sulfide, undergo two different refining processes – hydrometallurgical and pyrometallurgical, respectively. By global copper production volumes, pyrometallurgy is the dominant processing route.
Each ore deposit is unique in its concentration and mineral composition. Therefore, the most economical plant flowsheet varies from site to site. Even though the unit processes might be site-specific, the principle for the processing of sulfide ore remains the same.
Copper processing plants turn to flow control experts to isolate and control various process flows. In the upstream processing, valves regulate, for example, flotation and dewatering. In the downstream smelting and electrolysis processes, valves control, gas, air and electrolyte solution flows.
Valves for froth flotation
Valves commonly control the slurry feed and discharge, reagent addition and water flows in flotation equipment. Knife gate valves are used extensively in this application. Another typical valve type is rubber-lined butterfly valve. Segment valves are an excellent solution for the reagent feed and control.
Valves for dewatering
As particles become finer, the resistance against removing water increases. Dewatering can no longer be achieved by gravitation, so pressure must be utilized. A mechanical filter press is one option for the dewatering service. The machine contains several valves: Pinch valves are typically used in the slurry inlet feed, while the rest of the valves for water and air service often consist of butterfly valves.
Valves for the smelting process
The smelting process is a complex, multi-stage process involving high temperatures and molten liquids. Oxygen and air control are key to a reliable and efficient process. For these operations, valve materials need to be carefully selected, and cleanliness is of paramount importance due to the inherent danger of oxygen reacting with any grease, oil, or combustible material left in a piping system. The evaluation of valves for an oxygen application requires an understanding of metallurgy as well as valve geometries.
Valves for electrolysis
The electrolyte solution is piped to the tank. As pressures are typically rather low, butterfly valves are a good choice and provide the lowest total cost of ownership.