Namibia is one of the largest fluorspar producers in Africa. Acid-grade fluorspar is used as a raw material in the manufacture of nuclear products and for water fluoridation, and the fluorspar mining industry provides one of Namibia’s main income streams.
A fluorspar mine makes high demands for water to process ore. Water is a precious commodity in Africa but is a critical production element, so its management is a major issue for these mines.
Looking specifically at one mine, this location receives its water supply from two boreholes, and has also instigated a recycling programme to make use of waste water produced by the open-pit mining process. One borehole lies nine kilometres to the south of the mine, and the second borehole five kilometers to the north. At each borehole, and at the waste water containment dam, pumping stations have been built to push water to the mine works. Given the distances involved, pumping can prove problematic, so early detection of pump defects or a possible pipe burst are essential to maintain rates of excavation.
The mine wanted to create a new IP backbone infrastructure for its Water Control and Monitoring System. By integrating remote telemetry, audio, alarms and digital transmission for control with the existing IT network, the mine could ensure connectivity for troubleshooting from anywhere in the network, including remotely via VPN. Because of the distances involved and the physically extreme, mountainous nature of the mine site, the IP-based Ethernet Platform would need to be carried over a radio network.
Wood & Douglas and local partner Desert Technical Solutions (DTS) designed and implemented a wireless network to provide flexible monitoring and control of the mine’s water supplies.
Remote Terminal Units (RTUs) provide the physical interface with the water supply itself, presenting telemetry data in IP Ethernet format. This is achieved with flow meters providing the data from the remote pump sites, while monitoring and control of the Variable Speed Drives (VSD) on the pumps themselves enables the remote management of water pressure, ensuring the on-demand supply of water throughout the mine.
Given the long distances and challenges of the terrain, grid antennas with a 30 dBi gain were selected for the installation. Where no line of sight was available between the pump sites and the Control Room mast, a repeater station was installed with a self-contained 12V DC solar power supply with battery backup. For shorter distances, panel antennas with a gain of 19dBi were used.
To create the wireless Ethernet network between the boreholes, repeater station and control room, Wood & Douglas deployed its Insight radios. Operating on the 5.4 GHz frequency, Insight radios are specifically engineered for mesh, bridge and multipoint applications interfacing with IP or analogue. Rapid to install and set up, Insight radios provided a rugged, reliable, high-performance wireless link allowing data and video information to be carried over a single transmission link.
“Ethernet over a wireless network was far more cost-effective to implement and maintain than the alternatives available” -
Mine IT Administrator
- Cost-effective to implement and maintain
- Rugged, reliable and flexible
- Scalability ensures network remains future proofed