Low intensity continuous copper smelting

Abstract

As current advanced copper smelting processes are judged to be inherently inefficient, a case is made for a radical rethink of more appropriate technology to capture the energy content of high energy sulphides, such as chalcopyrite. Generic melt circulation employing non-oxygen enriched air top blowing in the non-splash mode with permanent linings of solidified copper matte is proposed. Two melt circulation loops are interconnected by a siphon to maintain automatically a continuous flow of high grade matte from the first melt circulation loop with a low copper metal activity into a copper saturated matte loop, which takes the place of traditional Peirce–Smith converters. Copper is removed continuously from the converting loop into two countercurrent packed bed gas–liquid contactors. The first packed bed employs controlled air oxidation of residual sulphur, followed then by the second packed bed using an excess of reformed natural gas for copper deoxidation in advance of continuous anode casting.