Solution
With the metallurgical plant running Rockwell Automation technology since 2001, Gold Fields directly commissioned Rockwell Automation to perform the control system upgrades. Rockwell Automation became involved with the new processing system via an EPCM contractor at South Deep Gold Mine. These two projects needed to culminate in a single, fully-integrated control, visualisation and reporting system.The mining solution using PlantPAx
The mining solution using PlantPAx™ is based on decades of mining domain expertise which has been formalised into a highly standardised, lifecycle-managed and easily commissioned solution that’s capable of reducing control system risks, improving diagnostics and reporting, and reducing system-wide complexities.
A more tailored and cost-effective alternative to a traditional DCS-based (distributed control systems) solution, the PlantPAx provides additional flexibility, managed mining-specific standards and reduced commissioning time and costs. This control system also helps ensure the same, high functional standards of a DCS-based system in terms of standardisation and single-tag databases.
System-Wide Implementation
The solution consists of a PlantPAx controller platform, configured to buffer up to 1 000 time-stamped data entries (plant history, events and alarms) to provide uninterrupted data logging in the event of a network failure.
For comprehensive visualisation of plant processes, the PlantPAx visualisation software, based on server-client architecture, was built into the system. ViewTools, licenced to PlantPAx, was also incorporated to provide the benefit of direct client access to the controller without the need for a path through the server.
Microsoft SQL, with built-in reporting services, was installed and configured to log all plant history, events and alarms. The mining solution’s licenced software, SQX, was also installed to allow the SQL to be populated directly by the controllers.
Rockwell Automation engineers further created unique interfaces to support third-party field devices, such as drives and instrumentation.
The final changeover was completed in November, 2012.
Results
Gold Fields was able to improve plant control, visualisation and reporting capabilities with the mining solution using PlantPAx.
Standardisation and comprehensively managed data logging enables the mining solution to provide users with a single, highly accurate status of the plant in real-time.
With the SQL configured to log history, events and alarms, users are able to follow trends, trace individual entries to specific end users, and keep track of analogue and digital inputs such as flow rates, temperatures and various other inputs from across the plant. All data is time stamped by the PlantPAx controllers, helping to ensure data integrity while allowing entries to be accurately injected into the SQL after a network failure has been corrected. Also, by adding SQX software, the SQL database can be added as I/O to the controllers.
The PlantPAx software processes signals from instruments and only report the minimum, maximum and average values per reporting period, which minimises the data logged to the database – as opposed to logging every signal from the field device.
Acknowledgement of alarms is user and time-stamped and logged, which protects operators from being reproached for ignoring essential warnings, while at the same time, improving accountability. This improves overall plant safety, especially at South Deep Gold Mine where cyanide alarms and other safety warnings are critical indicators.
