In converting, the impurities are removed from copper matte. The most important are iron, sulphur, lead, zinc, arsenic, antimony, tin and bismuth. At the converting stage gold, silver, nickel and selenium remain in the copper.
Sulphur is oxidized by oxygen enriched air to sulphur dioxide and is then normally converted to sulphuric acid. The iron is oxidized and bound to the silica present to form slag, which is then removed. The increase in copper content achieved during the converting phase after flash smelting is from 55-70% to 98%.
The treating capacity of matte per batch in Kumera Peirce-Smith Converters can vary between 100-400 tons, depending on the smelter capacity and other requirements.
KUMERA TECHNOLOGY CENTER (KTC) FI-11100 Riihimäki
Tel: +358 20 755 4200