Recent Operations at Hitachi Refinery

Abstract

Hitachi refinery of Nikko Smelting & Refining Co. Ltd. changed its operation scheme by introducing the ISA permanent cathode technology for the first time in Japan in December 2002. The change resulted in higher productivity, better cathode quality and lower operational costs. The operation has been continuously improved to reach a 20% higher production capacity than the original one.
For the electrolyte purification process, the Hitachi refinery introduced a sulfuration process in April 2001. This process removed sulfide (As, Sb and Bi) formed by the reaction of hydrogen sulfide from electrolyte with increasing in production of copper cathode by partially eliminating liberator cells.