Wireless telemetry enables smarter mine water monitoring

Remote monitoring specialist Omniflex has implemented a new wireless telemetry system for the Nkomati Nickel plant in South Africa, thereby facilitating mine-wide monitoring of its water and pumping systems. The mine has changed ownership several times since Omniflex originally supplied a telemetry system over a decade ago, with some of the original equipment reaching the end of its operational life.

Ian Loudon, international marketing and sales manager at Omniflex, said the mine’s hilly terrain is challenging for wireless communications as monitoring points need to be carefully positioned to maintain line of sight with the central control room. “Where a monitoring point is in a dip and can’t see the control room directly, we can route the signal through another nearby station — thus keeping all outstations on the network,” Loudon said.

The new system’s technical design accounts for the site’s varied terrain, with the lowest point between Pit 2 and Pit 3 potentially requiring signals to be routed through a repeater or another outstation to maintain connectivity with the control room. A technical survey also confirmed that the terrain is suitable for a radio telemetry system, building on the previous Omniflex installation.

The mine site’s exposure to lightning presents a further challenge, as the mountainous area is known for its high rate of lightning strikes. Surge protection, battery back-up and careful positioning of the equipment therefore form an important part of the system design.

The new system provides a modernised monitoring infrastructure, comprising six outstations connected to a central control room. It provides operators with visibility of flow rates, water levels and pump status across the site, with information transmitted to the control room’s SCADA system. This will allow Nkomati to keep track of water management more efficiently, while pumps can also be switched on and off remotely. If a pump trips while water is being transferred between dams, operators will receive the information almost immediately, allowing them to respond before the failure creates wider problems such as a pump failing to extract water, which could lead to a dam overflowing.

Omniflex’s modular approach allows additional monitoring channels to be added as Nkomati’s requirements develop, without requiring the system to be redesigned.

With limited engineering facilities close to the remote site, Omniflex also provided onsite commissioning assistance. Its engineers worked alongside Nkomati personnel during installation to help configure the system, troubleshoot connectivity and provide practical guidance on its operation. The first two systems have already been delivered with the remaining outstations expected to be installed over the next 12 months.

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