LMC has installed an FLSmidth ECS/ProcessExpert system to control the processing plant’s grinding circuit.
To optimise operation and to facilitate ramp-up to full production, LMC chose to install an advanced process control system. All the equipment installed in the grinding circuit was supplied by FLSmidth. LMC therefore decided to employ FLSmidth’s ECS/ProcessExpert system which is a hybrid using model predictive control supplemented by Fuzzy Logic to perform complex and continuous evaluation of process conditions. Comprising an open toolbox and specialised application, the ECS/ProcessExpert is specifically tailored to the needs of the plant and is able to execute control actions on a more frequent and reliable basis than possible by human operators.
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The system, which is designed to manage process control from the raw ore stockpile to the cyclone overflow delivery into the flotation plant, was installed at the plant in August 2009. After final commissioning, the system was evaluated over a three week a test period during which results were gathered and compared.
The LMC grinding circuit flowsheet (simplified)
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ECS/ProcessExpert control of the grinding circuit resulted in the following main achievements:
• Circuit stability on startup was attained twice as quickly with the system ON than when it was OFF (generally within 60 minutes).
• Cyclone feed pump energy consumption was reduced 3.4%.
• SAG mill weight variability was reduced 64%.
• The occurrence of load-induced undesirable impacts was greatly reduced.
• Improved stability and better pump control kept cyclone pressures in the optimum operational range for twice as long as was achieved under manual control.
• Pump speed process variability was reduced by more than 40%.
• Cyclone operational pressure process variability was reduced by more than 55%.
Although LMC are still ramping up production, the benefits already identified are expected to contribute significantly to increased revenue at this large copper mine.
The system utilisation factor at LMC is approximately 97% and reflects the high degree of confidence the plant operations personnel have in using the system.
FLSmidth is confident that the ECS/ProcessExpert installation will continue to deliver benefits and improved plant performance well into the future. The plant continues to be supported via remote monitoring and support services that allow FLSmidth to monitor the health of the system and to make adjustments to control strategies to suit the dynamic operational conditions if necessary.
FLSmidth is known for its advanced ECS/ProcessExpert control system and has delivered many such systems to the cement industry over the past more than 15 years. As FLSmidth continues to grow as a leading supplier in the minerals industry, the Automation Division now also offers leading edge control solutions to minerals processing plants.
FLSmidth ECS/ProcessExpert for Grinding Applications has been designed specifically with the following goals in mind:
• Circuit stability
• Circuit throughput optimisation
• Improved energy consumption
• Improved product quality
• Maximum equipment performance