Flash smelting

The process was developed by Outokumpu in Finland and first applied at the Harjavalta plant in 1949 for smelting copper ore.[2][3] It has also been adapted for nickel and lead production.

[4] The Inco flash furnace has end-wall concentrate injection burners and a central waste gas off-take,[4] while the Outokumpu flash furnace has a water-cooled reaction shaft at one end of the vessel and a waste gas off-take at the other end.

[5] The reactions in the flash smelting furnaces produce copper matte, iron oxides and sulfur dioxide.

[7] In most cases, the slag can be discarded, perhaps after some cleaning, and the matte is further treated in converters to produce blister copper.

In some cases where the flash furnaces are fed with concentrate containing a sufficiently high copper content, the concentrate is converted directly to blister in a single Outokumpu furnace[8] and further converting is unnecessary.