Methods of tin smelting.

Copper is currently mainly smelted by flash smelting; it can also be smelted using processes such as the Noranda furnace, AUSMELT, ISA, and SKS. In these methods, copper concentrate is fed into the furnace either dried or without drying, to produce matte copper, which is then converted into crude copper through blowing processes, followed by refining and electrowinning. Tin smelting involves two processes: direct smelting using AUSMELT furnaces by Yunnan Tin Industry Company, and smelting in reverberatory furnaces. In the former method, concentrate is fed into the furnace where oxygen is used for strong oxidation to remove sulfur, followed by strong reduction to extract tin, with the slag undergoing sulfidation and volatilization ； More companies use boiling roasting of crude tin ore mixed with coal, reduction smelting in reverberatory furnaces for the roasted slag, pyrometallurgical or electrolytic refining of crude tin, and sulfurization of the slag.