Optimizing Secondary Grinding Circuits with Real?Time Particle Size Tracking on Individual Cyclones

摘要

The prolonged duration of depressed metal prices has caused mine operators to change their focus away from adding new assets to increase capacity, to optimizing existing assets to increase throughput, recovery and efficiency. This change in focus resulting from a business crisis has been studied in other cyclic industries, and is understood to present an opportunity for significant changes, one of those being asset optimization.To identify the asset optimization process with the best economic return, one should search for key performance metrics that are not being adequately addressed by existing technologies. One of the most important metrics is particle size measurement of the output of grinding circuits that feed rougher flotation. For years traditional online particle size analyzers have been implemented in these applications; however, in many plants their availability has been unacceptably low to permit their reliable use in real-time process control. Additionally, maintenance requirements have been high due to lack of robustness and complexity of sampling systems. Importantly, since they only measure the consolidated output of an entire battery, they do not permit the use of control strategies that can identify and address individual cyclones that are performing poorly.This search for the best asset optimization project has recently led several concentrator plants to select and implement a novel particle size tracking technology on individual cyclones due to the deficiencies of existing technologies and the excellent financial metrics, such as a payback period of less than one year.This paper presents the CYCLONEtrac Particle Size Tracking (PST) technology that has been installed in nine large concentrator plants. Plant data will be presented showing the benefits of improved process control enabled by using strategies based on individual cyclone measurements, and consolidated measurements of the entire cyclone battery.