Recent Advances in ISAKIDD Cathode Design and Cathode Stripping Machines

Since the late 1970s, permanent stainless steel cathode technology has been employed in copper refining, beginning with Copper Refineries Limited in Townsville, Australia. The initial ISA Process featured copper-plated stainless steel hanger bars and split sheet cathodes. Later, the Kidd Creek operation in Canada introduced a solid copper hanger bar and enveloped (taco) cathode design known as the Kidd Process. Today, Glencore Technology has merged both technologies as ISAKIDD. This paper discusses advancements in cathode design and cathode stripping machine (CSM) development within the ISAKIDD technology. Although the cathode product remains either split or enveloped, hanger bar design has evolved based on operational experience and plant requirements, with two main designs currently in use. A newer hanger bar design, the ISAKIDD hanger bar, incorporates a copper core sheathed in stainless steel for enhanced corrosion protection from acid mist. Cathode blade materials have shifted from the initially dominant 316L grade austenitic stainless steel to duplex grade stainless steel, which favoured for its higher tensile strength and improved chloride corrosion resistance, making it suitable for harsher environments. To facilitate plate identification and tracking, refineries have the option to fit RFID tags to cathode plates, enabling more detailed data collection and analysis. CSM technology has seen ongoing improvements in automation, with newer machines employing robotics. However, older technologies like pivot arm semi-automatic machines remain popular in smaller operations due to cost-effectiveness and simplicity. The most recent ISAKIDD technology delivery to Nikkelverk's electrowinning plant includes a state-of-the-art robotic CSM, RFID-tagged cathode plates, ISAKIDD hanger bars, and duplex stainless-steel blades.