New casting moulds for anode copper

Norddeutsche Affinerie's (NA's) primary smelter continually increased production in the past decade. The smelter's concentrate capacity was expanded from 500,000 in 1993 to 1,000,000 t/a dry concentrate in 2000 and the goal of the present upgrade is 1, 150,000 t/a. These goals were reached without erecting new equipment in the anode area, but instead by refitting the existing plant. The life-span extension of the casting moulds was absolutely necessary to increase the casting performance from 260,000 to 450,000 t anodes per year on a single casting wheel. Different mould manufacturing processes and alloys were tested in order to find the optimal mould. In the past the moulds were cast directly, now the anode mould is milled into NA copper cakes. Accompanying measures taken were the shortening of maintenance and repair times as well as improvements in the refining furnace equipment.