SA mines need innovative methods of drought control

23rd November 2018

Barrier Balls could be the innovative drought control solution mining sites in South Africa have been waiting for, says South African mining engineering consultancy VBKom director Eduan Pieterse.

Founded by Chilean company Exma, Barrier Balls protect tailings ponds, water desalination pools and process water pools from evaporation by creating a floating cover system. Made from high-density polyethylene, the water-filled balls are 100% recyclable.

Together, they cover 91% of the surface they are placed on, consequently, creating a barrier that helps protect large masses of water from extreme heat and evaporation, says Pieterse in an October post on VBKom’s news blog.

By reducing the exposed surface and the passage of sunlight (photosynthesis), Barrier Balls significantly limit the loss of heat, the release of gas emissions and smells, and the growth of algae.

Further, by eliminating water mirror (wildlife attraction), pool contaminations and wildlife fatalities are reduced.

The Barrier Balls advantages comprise quick, easy and safe installation, which can be done when pools are full or empty, and requires zero maintenance. Fluid level variations are also automatically sorted, with the water freezing point lowered to –10 ºC.

The scalable solution can also operate in combination with aerators and mixers, it enables equipment to navigate and circulate through the liquid, and is unaffected by wind, powder, rain or snow.

Further, by reducing heat losses, biological reactions are kept in cold weather, while the solution captures and accumulates rainwater through permeable floating coverage.

“Positive results have been seen by The National Copper Corporation of Chile, which claims to have improved algae control and wildlife protection, while reducing evaporation, odour emissions and energy consumption,” states Pieterse.

With an expected life span of 15 years, he says, Barrier Balls could provide a long-term solution for not only the mining industry but for South Africa’s water crisis as a whole.

“Unfortunately, desalination is not a long-term solution. Not only is it expensive, but it holds negative effects for both the environment and humans.”

Unlike freshwater, Pieterse explains that seawater contains a chemical called boron. “During the desalination process, only 50% to 70% of boron is removed, leaving a substantial amount of the chemical behind. “Boron has been linked to reproductive problems and developmental problems in animals, as well as irritation of the human digestive track.”

Additionally, by-products of desalination include coagulants, bisulphates, and chlorines, he adds. The amount of concentrated waste deposited back into the ocean following desalination is extremely destructive to marine life and environments, killing 3.4-billion fish and other marine organisms yearly, Pieterse states.

In addition, he emphasises that the process requires 14 times more energy consumption than groundwater protection, while emissions contribute to climate change, a leading cause of the droughts.

“Mining companies in South Africa need to move towards more innovative, environment-friendly methods of drought control.” Founded in 2008, VBKom celebrates its tenth anniversary this year and offers consulting engineers who know how to successfully develop and optimise mining projects with drought management in mind, says Pieterse.

“Our mining consultants provide tailor- made mining engineering solutions for each unique challenge in our dynamic industry.”

Outsourcing for Survival

South Africa’s mining sector is showing signs of sustained recovery, but are “we out of the woods yet”, he asks in a June blog posting on VBKom’s website.

Mines that were able to sustain themselves during the three-year downcycle did so by outsourcing services and essentially lowering costs.

Outsourcing offers several solutions to the mining industry, notes Pieterse.

“Mining companies operate under permanent pressure. Operational targets, costs and profitability are all constant factors. When the three-year downcycle began, mines were left with no choice other than to cut costs, drop weight and reassess their investments. However, even with the recent signs of the industry’s revival, mines are still opting to outsource services instead of hiring their own in-house specialist teams.”

Although, he says outsourcing is more than just a cost lowering factor, explaining that outsourcing services give mines access to groups of specialists, their range of skills and the latest technologies – while also avoiding any long-term commitments. “Outsourcing gives mines the financial flexibility they need during a time of uncertainty.”

Additionally, job-shedding during the downcycle has left the industry with a lack of mine-based skills, Pieterse continues, stating that this gap needs to be quickly filled if mines wish to capitalise on higher prices. “However, it’s hard for mines to attract local talent with the correct skill sets while also ticking the small and medium-sized enterprises development box.”

Mining consultants are driven by task completion for compensation. Therefore, Pieterse says, opting for short-term contracts in the interim is the only way mines can ensure successful task completion. Further, potential graduates and professionals are now left with the challenge of filling senior positions and their duties, while also facing day-to-day operational and technical challenges.

“Outsourcing services to external mining consultants helps avoid duties being neglected, while also opening doors for possible learning and mentorship,” he concludes.