An in-depth process model was developed for the pyrometallurgical, off-gas systems and water
balance of the Kalgoorlie Nickel Smelter. This model was used to assess plant capacity with
changing concentrate grades, increased throughput and tighter environmental emissions under a
range of potential future operating conditions. Comparison of modelled results allowed for flow sheet
optimisation across a range of metrics including sustainability, processing capacity and costs.
Process modelling software, METSIM® (ver 2020.06 by METSIM International), was used to simulate
the flash furnace, integrated electric slag cleaning furnace, Pierce-Smith converters, matte
granulation, waste heat boiler, hot gas handling equipment, wet gas cleaning plant and acid plant.
The METSIM® model was divided into three separate, yet interconnected models: metals, off-gas
and water balancing. This allowed for improved modelling efficiency and traceability while minimising
manual error.
The METSIM® model was supported by inputs from other specialised software. Chemical
thermodynamics software, FactSage™ (ver 8.2 by GTT Technologies), was used to establish
relationships for the flash furnace fluxing strategy and determine the operating temperature. Arena®
(ver 16.0 by Rockwell Automation), a discrete event modelling software, was used to simulate
material movements within the aisle as well as Pierce-Smith converter operation, allowing for
integration with upstream and downstream systems. A dynamic data exchange (DDE) was used to
connect the results of each software package, interfacing through Excel® (version 4203 by
Microsoft). The integration between models provided a streamlined approach to test capacity,
bottlenecks, water consumption and emissions under a range of operating conditions, enabling a
more robust process.
Further downstream modelling techniques were used to assess mechanical equipment. METSIM®
outputs provided key parameters for combustion assessments using computational fluid dynamics
and finite element analysis for the furnace mechanical design.