:: MIPAC Stabilises Zinifex Century Mine

Zinifex’s Century Mine is the second largest zinc mine in the world in terms of production. It has a very large and complex flotation circuit which is very sensitive to grinding circuit performance. In 2006, Zinifex commissioned MIPAC to review its operations and then design and implement improved SAG mill control. MIPAC completed the project in 2007 and as a result, has provided Zinifex with automatic stabilising control for the primary grinding circuit at Century Mine. The system has been implemented using the plant DCS with significant emphasis on producing a robust system which can be easily maintained by local site personnel.

As a core basis for the project, MIPAC utilised four key strategies:

• Determined the real requirements of Century personnel
• Making the best use of the plant DCS
• Loop-tuning and commissioning skills
• Support for operators to understand and use the system

Specifically, MIPAC provided the following services:

• Control and instrumentation audit of the grinding circuit
• Grinding expertise (from a process control perspective)
• Design of the new control strategy
• Operator training and testing, commissioning and support
• Evaluation of the new control strategy

“Century Mine recognises that grinding is a critical process in operations and it is important to have a good quality, robust, high performance control system that can be maintained independently, said Andrew Thornton, Principal Process Control Specialist, MIPAC “They embarked on this project with a view ultimately to improving recovery and therefore production output and profitability."