A new process to recycle copper and copper alloy scrap

The present technological cycle to produce secondary copper includes two main steps: a preliminary thermal refining to produce cast anodes having a copper content of about 99%, followed by anode electrorefining to produce HSG copper. The new proposed process avoids the pyro-refining operation and produces anodes by cold compacting of granulated copper and copper alloy scrap. The direct electrorefining presents economical and environmental advantages due to furnace exclusion, but also to the possibility of using low-grade scrap. Once the electrorefining has been tested on a laboratory scale by using parameters similar to those used in traditional operations, the main critical aspects of the process have been analyzed. In particular technology of anode production, best scrap size, compacting parameters, anodic scrap residue and electrolyte purification process have been tested on a laboratory pilot plant.