As commodity prices surge in these inflationary times, mining activity continues to increase. Miners can increase their throughput, efficiency, and sustainability by applying advanced process control in their operations. In a North American Mining article, Optimizing all the variables related to comminution and separation requires sophisticated control strategies, Emerson’s David Harrach teamed with Devin Marshman from Emerson Impact Partner, Spartan Controls.
David and Devin open by describing the ore processing process.
Ore processing operations connected with mining sites are a critical but costly step in the larger effort to produce refined metals. Regardless of the final purification process, ore must be prepared to meet refiner composition specifications, create optimal particle size, support preliminary separation, and impart other characteristics necessary to ensure efficient final separation, whether by chemical means or traditional smelting. Steps can involve grinding, screening, thickening, flotation, and others to achieve the desired intermediate product.
Energy consumption is high, especially when grinding ore.
Grinding operations are generally the most energy intensive steps of a processing plant, often consuming up to 10 kilowatt hours per ton of ore processed.
They describe regulatory control at the base layer, which handles the basic ore processing requirements. Advanced Process Control (APC) can address some more complex processing requirements. Model Predictive Control (MPC):
…has gained popularity for ore processing because it can handle complex operations where there are multiple potential variables. Under operating conditions where the process is generally stable and changes are gradual, MPC can be effective, so it should be in a designer’s toolbox.
Integrated Quadratic Control (IQC)
Integrated Quadratic Control (IQC):
…is a single-input, multi-output controller… that uses velocity-form quadratic optimization to split the output signal. This allows it to control multiple functions simultaneously, even to the point of adjusting and optimizing its strategy where it has multiple options to achieve the desired setpoint.
David and Devin explain how IQC is most successfully applied in SAG mills and flotation separators because it can balance:
…multiple variables, while responding quickly to process changes and upsets.
Read the article for more specifics of how IQC can effectively manage the challenges and complexities in these two applications to drive throughput, efficiency, and sustainability gains. Visit the Mining, Minerals & Metals section on Emerson.com for ways to help you extract more availability, more efficiency, and more productivity from your operations.
