Kamoto Copper Company (KCC)
Process Plant Optimisation
- Location: Democratic Republic of the Congo (DRC)
- Industry: Mining
- Control System: Siemens Step 7 (PLC) and WinCC (SCADA)
Project overview
Kamoto Copper Company (KCC) is a Glencore operated copper and cobalt mine located in the Democratic Republic of Congo. Mipac was contacted in 2020 to help commission and optimise the operations at the Kamoto Concentrator (KTC) plant and the nearby Luilu Refinery.
Work by Mipac on the first and second stages focussed on the Mills at KTC and CCD circuits at Luilu. Seven grinding mills for oxide and sulphide ores. The second stage focussed on automating the underflow control of the CCDs.
![[3:48 pm] Andrew Hislop two men looking at pipes, valves and pumps on a mine site wearing high vis, discussing how to make logic for its automatic control](data:image/svg+xml;nitro-empty-id=OTE2OjE0Mzg=-1;base64,PHN2ZyB2aWV3Qm94PSIwIDAgMTAyNCA3NjgiIHdpZHRoPSIxMDI0IiBoZWlnaHQ9Ijc2OCIgeG1sbnM9Imh0dHA6Ly93d3cudzMub3JnLzIwMDAvc3ZnIj48L3N2Zz4=)
Background
Mipac has been engaged to provide several different services to the KCC mine. The initial engagement came during the COVID restrictions on travel. Mipac’s ability to assist with optimisation from a remote connection and with experienced engineers being able to guide and assist operations without being there in person was why we were selected to assist.
Mipac was able to apply our remote methodology to execute the KCC’s Mill Control assistance. Mipac’s remote engineering resources defined, configured, deployed, monitored, troubleshooted and supported the automation and optimisation projects.
Scope
The scope of this project included:
- Reviewed the existing logic, working with site engineers to identify improvements
- Prepared Functional Descriptions for new control strategies
- Implemented first mill control strategy (commission and test) remotely and monitored
- Replicated the control strategy for mills 1 - 7
- Monitored and identified further advanced improvements
- Developed feed forward underflow control for the CCDs
- Derived key performance KPIs, including automatic control utilisation
- Developed AVEVA PI Vision dashboards for monitoring KPIs and performance data of key process units
- Implemented downtime monitoring software (RtDuet) for key process units
Further work is being undertaken in stages to continue to optimise and commission plant at the KCC site.
Project challenges
Lack of physical connection with mine
One of the key challenges of this project was the lack of physical connection with the mine. In the past, discovery visits to site would allow the Engineering team to identify and observe the process issues at the site. Armed with this first-hand knowledge of the plant, they can remotely develop a strategy and control system that is then implemented in person on subsequent site visit/s. This case was an example of how Mipac was able to complete discovery, planning and commissioning all without stepping foot onsite.
The safe and successful implementation of project scope has flowed into real-time collaboration and problem-solving with site engineers to address operational issues.
The ability to problem-solve remotely with the client, working together from opposite sides of the world, was a unique opportunity to showcase Mipac’s remote support capabilities. Mipac has been offering this capability to the market for over a decade, but the pandemic made remote commissioning and support a skill that was essential to continue development in areas where travel was severely impacted.
Operating in a shared engineering station
PCS engineering is performed from a single engineering station which must be shared by site engineers and contractors, which makes time consuming tasks such as implementing and commissioning complex control logic and tuning control loops particularly challenging. Mipac has built trust with site engineers and worked flexibly to share the engineering station access in a busy operational environment.
This has included following the KCC MOC procedures, providing post-implementation reports and continuous communication with site personnel to plan and execute works safely and successfully with minimal impact on operation.
Mipac has been able to improve the visibility of plant performance and operational behaviour by creating PI Vision dashboards. Simple dashboards tracking the percentage time that certain process units are in automatic operation help to drive the transition from manual to automatic operation when new control strategies are implemented. Training packages on new logic are also provided to operators and engineers.
Achievements
Feeder control implemented
Feeder control on the mills was implemented to combat the empty feeder occurrences where feed may be disrupted by a feeder running out of ore. Coupled with new load and power control for the mills, the feed is optimised to achieve setpoint for the target feed and to maximise throughput within the power and load constraints for the mills. Cyclone control is now managed to pressure setpoints to obtain the best COF p80 for downstream processes. The cyclone feed hopper level control, cyclone pressure and COF mass work together to minimise disturbances and avoid spillages.
Post leach continuous counter-current decantation (CCD) was being run in manual operation and was creating recovery problems. Enabling a feed forward underflow control allowed autonomous operation of the CCD’s, thereby reducing operator involvement while providing more stable operation and improved recoveries.
Totalisers added to the pre and post leach circuits
Totalisers have been added to the pre and post leach circuits to allow the operations to better balance solids within the circuit and improve recoveries further. This improvement came from listening to the metallurgists at KCC and finding a solution to their pain point. Good communication has been essential in providing effective solutions.
New water constraint logic coded and approved
Assisting the site metallurgists with a series of repetitive cyclone blockages causing the main mill to experience downtime led to the identification of a site water constraint. New water constraint logic for the mills was coded and approved for implementation rapidly to respond to the site issue. Effective diagnosis provided by experienced operational engineers saved the site team from repetitive downtime.
Results
Remote commissioning of feed, load and power control optimised throughput and freed up operator time
- Feed, load and power control for Mills for the KTC plant have been commissioned remotely.
- The implementation of autonomous feeder control improves the throughput for the mills.
- Load and Power constraint control has optimised the throughput for the mills.
- Stability around the cyclones and autonomous control means the operators can focus on other priority tasks for the day.
- Improved throughput and stability around the cyclones improved the downstream processes for the site.
- Improvements to the feeder electrical and mechanical arrangements were able to be identified through commissioning that allowed the site team to fix issues of which they were not aware.
- Mipac developed and implemented new control system logic for the Kamoto Copper Luilu CCD circuit to improve throughput and stability. According to the feedback from site personnel, the logic has stabilized the plant operation and reduced the downtime.
- Introduction of the new logic also improved stability of the CCD Train 1. It brought average rake height under 100mm for each unit and resulted in reduced fluctuation of rake torque.
- There were no significant changes observed in the overall throughput of CCD Train 1 with the introduction of the new logic. However increased throughput was achieved for each unit within the train. The most probable cause of this anomaly is incorrect readings from the density meters.
- Overall, there is enough evidence to conclude that the introduction of the new logic resulted in throughput increases of at least 10% for the individual units within the train.
Where to from here?
Future works to assist with commissioning of flotation mass pull logic and precipitation tank level control demonstrate KCC’s confidence in Mipac’s remote capability. And with COVID restrictions ending, we look forward to visiting site to further meet and build on the foundation already established.
