October 6, 2022
THE ROSH PINAH underground zinc-lead mine, located in southwestern Namibia, has been in continuous operation since 1969. Operated by Trevali (TSX-T), there was a need for the mine to increase both the quality and the quantity of the ore delivered to the plant. Despite having excellent mine plans, they found it hard to accurately forecast production. This was down to difficulties in merging interdepartmental short-term plans, performing conflict resolution, orchestrating pre-shift tasking, and controlling the impact of unplanned work in-shift.
To address those issues, Trevali partnered with MineRP, an Epirocowned software company – headquartered in Centurion, South Africa – specializing in increasing mine productivity through digitally-enabled enterprise interoperability, integrated planning, execution and analytics.
"There were three basic challenges: to integrate all data into one platform where everybody can make use of it, to reduce the dilution of the ore by having a good quality blast every day, and to better understand the mine’s constraints and bottlenecks so that planning and task assignment could be improved", says Jurgens Visser, Mining Executive at MineRP.
When trying to meet the challenges, MineRP had full access to Rosh Pinah’s data. The main task was to create an Integrated Operating Scheduling (IOS) system, a MineRP platform-based solution designed to improve planning and execution. Another important component was to develop a Short-Term Dilution Management solution, in order to stabilize the quality of the plant feed. It was combined with continuous volumetric monitoring.
“The biggest costs for a mine are people and machines, so you cannot afford to lose production hours due to them standing idle,” says Jurgens Visser. “The most important thing for us was to improve the short-term planning through the IOS. The mine used to have separate production schedules and maintenance schedules, and these schedules often conflicted with each other. Our approach was to help Rosh Pinah deconflicts the scheduling between production and maintenance, so there is no constraint on the tonnage capacity due to these conflicts,” says Visser.
The MineRP platform was used to bring on board not only mine planning and design elements, but all of the planning that affects the mine. The IOS that was created reflects all planned work, not just the production activities.
“Success is a combination of proper scheduling and proper task management. This addresses conflicts in the schedule, as well as conflicts caused by emerging work. For example, if something goes wrong during a shift, that information is brought into the schedule so that the next shift is minimally impacted," says Visser.
"We always say that a mine should plan the work and work the plan. What often happens is that they plan the work, and work the mine, so to speak. They get underground and do whatever they are able to do, since there are so many interruptions and unexpected conditions to deal with. Thanks to the integrated schedule Rosh Pinah was able to minimize these unplanned interruptions and actually work the plan."
The improvement started when it was noted that the development detail was on budget. Also, there was much better control of the grade according to the plan. Dilution is still a bit of a challenge, but improvements have been made.
“The daily tons have also improved. During the third quarter of 2021, Rosh Pinah exceeded the daily target almost every day. All in all, better quality tons are coming through the system, the development has improved, and the grade is on target based on the budget," says Visser.