Which types of furnaces are used for tin smelting?

In the process of tin smelting, three primary types of furnaces are utilized to reduce tin oxide into tin metal:1

• Reverberatory furnaces: These are the most commonly used furnaces for tin smelting. In this type of furnace, the fuel does not come into direct contact with the ore; instead, the ore is heated by a flame that is deflected over it from a separate chamber.12
• Blast furnaces: These are also employed in the smelting process to facilitate the chemical reduction of tin oxide using carbon.1
• Electric furnaces: These represent the third basic type of furnace used for smelting tin concentrates.1

Before smelting occurs, low-grade concentrates are often prepared in a reverberatory or multiple-hearth furnace to remove sulfur through roasting. Additionally, reverberatory furnaces are used during the refining stage for a process known as liquation, which separates tin from impurities with higher melting points.13