Highly Efficient Slag Cleaning–Latest Results from Pilot‐Scale Tests

Modern life would not be possible without copper. The high worldwide demand for copper raises several questions for the copper industry in terms of economic and ecological considerations regarding the main product copper as well as the by-product iron silicate. The future challenge for copper smelters is to increase the yield by reducing the copper losses and to obtain the iron-silicate as a marketable by-product. This can be achieved by further treatment of the slag. A newly developed slag cleaning technology has been evaluated in a specially designed pilot furnace integrated into an industrial process. Applying a magnetic field across a DC field improves stirring, thereby fostering the settling of entrained copper droplets. The results showed that a 30 % to 50 % reduction of the Cu content in the iron silicate product is feasible, depending on the composition of the incoming copper slag. This makes the process economically attractive.