Removal of zinc from a base-metal solution using ion exchange at Rustenburg Base Metal Refiners.

Anglo American Platinum’s expansion project, which aimed at increasing platinum production to 3.5 million oz per annum, necessitated an expansion in the Rustenburg Base Metal Refinery (RBMR) to accommodate the associated increase in the production of base metals (Cu, Ni, and Co). RBMR’s name plate capacity increased from 21 000 to 33 000 tonnes of nickel per annum. The expansion project involved various brownfield and greenfield installations and was completed in 2011. The new circuit and various process additions posed a significant risk to the nickel cathode quality with regard to zinc contamination. Mass balancing of the pre-expansion circuit showed that as much as 50% of the zinc entering the plant would exit through the nickel cathode, thus making it the major bleed for zinc from the circuit. The expansion circuit mass balance showed that although a portion of the zinc would exit through the pressure iron removal residue, this small bleed stream would not be sufficient to ensure that the nickel cathode does not exceed 50 ppm (LME specification). Another factor contributing to the zinc problem was the fact that more Platreef ore, with higher zinc levels, was being mined. These factors indicated that a dedicated zinc removal section was required to ensure a sustainable nickel cathode production containing less than 50 ppm zinc.

Grantor dc:publisher.institution

Centre for Bioprocess Engineering Research

Year dc:date.issued

2013

Author dc:creator

• Taute, Jacob Johannes

Advisor dc:contributor.advisor

• Petersen, Jochen

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/5610

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/5610