Tag Archives: Northern Cape

Kumba’s Kolomela, Sishen iron ore mines to deploy Rosond nex-gen exploration drill rigs

Rosond of Midrand, South Africa, is combining automation, software, data analytics and machine learning to create a next-generation drill rig that will help transition the company from contractor to technology provider.

The company dispatched the final batch of 28 state-of-the-art drill rigs to Anglo American’s majority owned Kumba Iron Ore operations in the Northern Cape in December, to be rolled out at Kumba’s Kolomela and Sishen iron ore mines. This forms part of a R2 billion ($134 million), five-year tender clinched by Rosond to supply Anglo American with the latest drilling technology as it modernises its geoscience operations.

“We really believe that this is going to be a future game changer,” Ricardo Ribeiro, Managing Director of Rosond, said.

In the face of COVID-19 lockdown restrictions, Rosond said it was able to compress a year’s work into six months. It collaborated with a leading Italian manufacturer to develop the advanced drill rigs, which will be deployed for core, percussion and reverse circulation drilling.

“I am happy to report that the last two drill rigs were dispatched in December 2020,” Ribeiro added. “We are excited to see the entire fleet operational early this year. These are some of the most highly-advanced exploration drill rigs in the world.”

The drill rigs feature increased safety with the automation of most of the arduous and dangerous manual labour involved, Rosond says, taking away the need to handle the drill rods, and load and unload heavy equipment from the drill rigs.

The rig operators are housed in a climate-controlled, air-conditioned control room for an improved work environment that, in turn, assists with fatigue management and also boosts productivity and accuracy, Rosond says.

The opportunity to build such rigs also arose with several women being deployed as part of a team at Kumba. Recruiting and training this team formed part of Rosond’s tender with Anglo American, Ribeiro explained.

Rosond took the strategic step in 2012 to begin developing new technology for the drilling and exploration sectors, with the drill rigs leveraging the latest developments in software, telemetry and automation.

“We brought in a lot of technology from the construction and oil and gas industries to develop specific functionalities such as dust suppression and automation, as well as software and telemetry systems,” Ribeiro said.

The 28-strong fleet at Kumba will be deployed in an 80 km radius to optimise exploration drilling by providing critical geological data about the sites under investigation, Rosond says.

Having successfully developed the hardware of the new drill rigs themselves, the future plan is to launch a software division to focus on the application of data analytics and artificial intelligence in optimising the drilling process, as well as promoting machine learning.

“We are optimistic that in the future our drill rigs will be able to identify all the necessary parameters in order to be able to guide the operators seamlessly,” Ribeiro said. “The end goal in our development process is to have a full autonomous drill rig.”

East Manganese project gears up for production following regulatory approvals

The East Manganese project in the Northern Cape of South Africa has been granted a water use licence, paving the way for mining operations to commence soon.

Menar’s first manganese asset located near Hotazel, the R250 million ($15.1 million) project was granted environmental authorisations in February 2019, a mining right in August 2019 and water use licence last month.

Sitatunga Resources, whose major shareholder is investment company Menar, acquired East Manganese in 2018.

Menar Managing Director, Vuslat Bayoglu, said the timely approvals were encouraging for the company’s planned investments in the medium term.

“East Manganese is part of our group’s planned R7 billion investments,” Bayoglu said. “Speedy regulatory approvals are critical to unlock the investment spend and to contribute to South Africa’s economic revival. We are, therefore, impressed by Human Settlements, Water and Sanitation Minister, Lindiwe Sisulu’s, recent undertaking to continuously improve turnaround times for applications.”

East Manganese holds an approximate 1 Mt run of mine (ROM) resource, and will produce around 30,000 t/mth ROM manganese ore, according to the company. Due to the conical shape of the proposed pit, it will take some 7-8 months to reach first ore, after which steady-state production will be achieved swiftly, Menar said.

East Manganese will be an open-pit mine with a single, 14 ha pit located on a small 50 ha portion of the total 1,000 ha mining right area. The remaining unused portion of the mining right area will be used for cattle and game farming by a local farmer, Menar says.

The mine will utilise a dry crushing and screening plant system, which will reduce water usage at the plant, to produce lumpy (85%) and fine (15%) particle manganese products.

Bayoglu pointed out that all the mine’s infrastructure will be powered by solar energy, including its offices and weighbridge.

The decision to diversify the Menar Group’s commodity portfolio is in keeping with its aspirations of becoming a leading South African diversified mining company, Bayoglu said.

“We are committed to realising South Africa’s full mining potential by continuously seeking out new investment opportunities and East Manganese is a clear illustration of this continued commitment,” he said.

He added: “The establishment of the East Manganese mine will aid economic activities in the area and create between 70-80 direct new jobs on the mining complex once peak production has been reached. If we multiply this figure by 10 [which is the average number of people that are dependent on a single salary earner in South Africa], then, in essence, 700 -800 people will directly benefit from this project.

“In addition, the indirect economic benefit of the operation, even though not quantifiable, is also far reaching. The mine’s recruitment process is being undertaken in conjunction with Joe Morolong Local Municipality which, through its Local Economic Development forum, has been very helpful to date.”

Orion settles on SAG milling and water treatment at Prieska Cu-Zn project

Two significant engineering changes have had a positive impact on the expected returns from Orion Minerals’ Prieska copper-zinc project in the Northern Cape Province of South Africa.

Issuing an updated bankable feasibility study (BFS) for a proposed new 2.4 Mt/y copper and zinc mining operation earlier this week, the company said there had been “numerous improvements” on the previous study completed in June 2019.

This included a 43% increase in post-tax undiscounted free cash flows from the project to A$1.2 billion ($798 million); a 36% increase in after-tax net present value (8% discount rate) to A$552 million; and a five-month reduction in the capital payback period to 2.4 years.

In the plant, the major changes include the use of SAG milling, and removal of secondary crushing, screening and rock conveyors.

The use of a SAG and ball milling circuit followed by differential flotation removes the need for multiple stages of crushing – which was included in the previous study.

The new plan envisages a high steel charged SAG mill operating in an open circuit with a secondary ball mill operated in a closed circuit with a classification cyclone cluster. The SAG mill trommel screen oversize feeds a pebble crushing circuit which returns crushed product to the SAG mill feed conveyor, the company said.

The milling circuit, meanwhile, is fed with (F100) 250 mm primary crushed material from the primary stockpile at a throughput rate of 300 t/h and produces a product size of 70% passing 75 μm, which is fed to the differential flotation circuit.

In a presentation, Orion stated that the processing plant costs from the 2019 study to the latest BFS had dropped 16% to A$91 million.

The next big change was a different de-watering philosophy of the old workings of Prieska, with the BFS including a new water treatment route. This resulted in a 30% decrease in the shaft dewatering timeline, it said.

The Hutchings Shaft and underground workings at Prieska are currently filled with water to a depth of 310 m below surface and contain a volume of 8.6 Mcu.m of water.

Dewatering of the workings via a pumping system to be installed in the Hutchings Shaft is now planned, with water being pumped into a 1 Mcu.m volume dewatering dam on surface, from where mechanical evaporators and a reverse osmosis water treatment plant will be used to dispose of and treat the water for discharge into the environment.

The use of water treatment supplements mechanical evaporation, which allows the pumping schedule to be accelerated by four months, Orion said. “Furthermore, the Department of Human Settlements, Water and Sanitation stipulated as part of the IWUL (Repli Integrated Water Use Licence) application process that provision be made for a portion of the dewatered volume to be made available for social, commercial or agricultural use in the locality.”

Forced evaporation is planned to be used as the primary means to dispose of the water with the water treatment plant (WTP) as the secondary means to treat and then discharge treated water into the environment as irrigation water.

Forced evaporation requires the use of a large evaporation dam, according to Orion, which impacts environmental considerations when compared with the small footprint required by the WTP.

“This is mitigated through the early construction of the tailings storage facility (TSF) which serves a dual purpose for early project phase dewatering and later as a TSF during the operational life of the mine,” the company said.

These actions, in addition to prioritising the extraction of higher grade (and confidence) mineral resources earlier in the mine schedule, helped significantly improve the project return economics, according to Orion.

While the changes also came with a 9% increase in peak funding requirements to A$413 million to cater for the operational improvements, it would also see 20% more payable copper produced – 226,000 t – and 17% more payable zinc produced – 680,000 t – over the 12-year mine life.

Orion’s Managing Director and CEO, Errol Smart, said: “With the Prieska BFS update now complete, the development of the Prieska project is ideally positioned to play a vital role in the local economic recovery plan for the Northern Cape region.

“The project’s low exposure to imported materials and foreign labour reduces construction challenges as the world overcomes and recovers from COVID-19.”

Smart added that the company was targeting a production start-up in 2024 as market conditions permitted.

Kwatani upskills Northern Cape contractor to carry out maintenance work

Specialist vibrating equipment manufacturer, Kwatani, says it leveraging a recent multi-year service contract with a large mining customer in the Northern Cape of South Africa to further boost the area’s local economy.

Kim Schoepflin, CEO of Kwatani, said: “Our branch near the customer’s mining operation has for many years employed and developed local expertise. Our latest initiative takes this further, by upskilling a local sub-contractor to conduct certain maintenance work on our behalf.”

A lengthy selection process was conducted by Kwatani to find a suitable sub-contractor, followed by ongoing training to empower artisans and other workers with specialised skills. Schoepflin says it was also important to involve the mine itself, so that it remained confident in the strength of its supply chain.

“Promoting local employment, skills and sustainability cannot be a tick-box exercise,” Schoepflin says. “It has to be based on proper engagement, hands-on training and the sub-contractor’s own commitment.”

Mining legislation and regulatory pressure can tempt stakeholders to rush such a process, she warned. “This would be a mistake; rather, it should be treated as an opportunity to strengthen the capability of all stakeholders.”

Kwatani’s 35 years of experience in heavy duty minerals applications means the OEM now has around 800 vibrating screens and feeders in the Northern Cape. The maintenance contract is an ideal opportunity to involve and foster the technical capability of local players, Schoepflin says.

It was vital that the chosen sub-contractor already had considerable experience and capacity, equipment and relevant expertise, according to the company.

“As a South Africa OEM with our own technologies and intellectual property, we are able to certify the sub-contractor and their quality of work,” Schoepflin says. “Phase 1 of our initiative will see them conducting basic service and maintenance functions.”

Kwatani retains responsibility for all work conducted, and continues with services such as detailed technical inspections, engineering support, on-site testing and diagnosis. It also supplies OEM spare parts, ensuring quality control, increased lifecycle time and reduced downtime, the company said.

Schoepflin noted that communities countrywide are eager to see more benefits from economic activity, and the country’s Mining Charter provides clear guidance on how mining companies can contribute to this process. “Kwatani’s mining customer is therefore also eager and incentivised to promote local businesses, both directly and through the supply chains of its main local contractors,” Kwatani said.

Schoepflin highlights the importance of supporting local firms to build sustainability in the local economy. This also strengthens the skills base for this economy to diversify, making it less dependent on mining and more resilient to commodity cycles and eventual mine closure.

“Our own business is local from the ground up, sourcing 99% of direct purchases from inside South Africa,” she says. “So, we understand the positive role that local procurement and skills development can play.”

It also makes financial sense to root the company’s cost base in the local currency, making it less vulnerable to foreign exchange fluctuations and allowing more affordable and consistent pricing.

“Working collaboratively with our mining customers and businesses close to their operations, we can help spread local economic benefits,” she says. “In turn, we can continue to develop our focus on leading-edge technology and quality manufacture.”

Orion Minerals looks at renewable options for Prieska zinc-copper project

Orion Minerals, through its subsidiary, Repli Trading No 27, has entered into a collaboration agreement with juwi Renewable Energies South Africa to investigate renewable energy generation for its Prieska zinc-copper project in the Northern Cape of South Africa.

The preliminary scope is to investigate the feasibility of generating and supplying 35 MW of electricity for Prieska, from a hybrid power system using integrated wind and solar technologies. The renewable energy generation site will be located within 20 km of Prieska, making the establishment of a dedicated feed via an overhead power transmission line possible, Orion said.

juwi is part of the international juwi Group, one of the world’s leading renewable energy companies. Its business is focused on both solar energy and onshore wind energy. To date, juwi South Africa has built five utility-scale solar plants totalling 121 MW and developed the 138 MW Garob Wind Farm, which will soon start construction.

juwi South Africa also participates in the South Africa Government’s Small Independent Power Producer Program and operates and maintains all its solar projects on behalf of their owners.

In Australia, juwi was recently responsible for the project development, design, construction and now operations of a $40 million, 10 MW solar power facility which came into commercial operation in 2016 at Sandfire Resources’ DeGrussa copper-gold mine in Western Australia. Orion said: “This facility has since attracted international attention as the largest off-grid integrated solar and battery storage facility in the world. With close to three years of operational data and 100% uptime, this successful project has established juwi as leaders in hybrid power supply solutions for mines.”

The investigations into renewable energy solutions at Orion’s Prieska project will complement the ongoing bankable feasibility study, with the additional benefit of potentially improving the base case plan of obtaining national grid power directly from the Cuprum sub-station already established on site, Orion said.

“Developing the renewable energy potential of the region is also a strategic goal of local government, as communicated in its Integrated Development Plans,” Orion said.

The Prieska copper mine operated from 1971 to 1991, employing approximately 4,000 people. The mine milled 46.8 Mt, producing more than 430,000 t of copper and more than 1 Mt of zinc in concentrate. Post May 1987, no more than 2 Mt of ore was blasted, with milling of surface stockpiles carried out from 1989. In 1991, the mine was closed and the site rehabilitated. It now has a defined maiden resource under the Orion ownership of 1.1 Mt of contained zinc grading 3.8% Zn and 365,000 t of contained copper grading an average 1.2% Cu. The deposit is regarded as one of the world’s 30 largest VMS orebodies, according to Orion.

President cuts the ribbon on Vedanta’s Gamsberg zinc mine in South Africa

South Africa President, Cyril Ramaphosa, has officially opened Vedanta Zinc International’s (VZI) Gamsberg mine, outside Aggeneys in the Northern Cape Province.

Ramaphosa was joined by Minister of Mineral Resources, Gwede Mantashe, Northern Cape Premier, Sylvia Lucas, and hosted by Vedanta Chairman, Anil Agarwal, Vedanta CEO, Srinivasan Venkatakrishnan, and VZI CEO, Deshnee Naidoo, at the ceremony.

The Gamsberg zinc resource, though discovered more than 40 years ago, had been held undeveloped in the portfolios of various South Africa mining companies until Vedanta acquired it in 2011, as part of the Black Mountain Mining complex. Vedanta gave the project the go-ahead in 2014, and the first blast occurred in mid-2015, eight months later. Gamsberg has a reserve and resource of more than 214 Mt with a grade of 6-6.5% Zn and an estimated life of mine (LoM) of 30-plus years.

Phase 1 of Gamsberg, celebrated today, represents a $400 million investment by Vedanta in South Africa. It has a LoM of 13 years and will see 4 Mt/y of ore produced from the open pit and 250,000 t/y of concentrate from its concentrator plant.

Investigations into Phase 2 and 3 are underway and will see production of zinc-in-concentrate increase to 450,000 t/y, and in a modular fashion ultimately, to 600,000 t/y. It will reflect an additional investment of $350-$400 million.

Vedanta is simultaneously pursuing a feasibility study into the development and construction of a smelter-refinery complex, it said.

Vedanta’s CEO, Srinivasan Venkatakrishnan, said: “More than 90% of our $400 million investment at Gamsberg has been spent in South Africa. Our expenditure with local enterprises was around R77.5 million ($5.5 million) in 2018, while we invested more than R44.6 million in 2018 on training and social projects aimed at skills development, education, health, enterprise development and municipal infrastructure support. And this was before the mine had made a single cent.”

Delivering the keynote address, Cyril Ramaphosa, said: “The Vedanta Gamsberg project is an important step in our shared journey to revive our mining industry. It confirms our view that with an effective regulatory framework, improved collaboration between all stakeholders and sustained investment, mining has the potential to be a sunrise industry. South Africa has vast undeveloped mineral deposits that we have the opportunity to exploit for the benefit of all the people of this country.”

Gamsberg is one of the most digitally advanced greenfield mining projects in South Africa, according to Vedanta. Digitalisation at Gamsberg includes Smart Ore Movement, Spatial Risk Monitoring and Management and Collision Avoidance Systems.

Weir Cavex hydrocyclones prove their worth at South Africa diamond mine

Weir Minerals’ Cavex® hydrocyclones have been put to the test at a diamond mine in South Africa’s Northern Cape Province, proving the technology can be applied in dense medium separation (DMS) plants treating diamondiferous material, according to the company.

In her presentation to the Southern African Institute of Mining and Metallurgy (SAIMM) diamond conference in Johannesburg in 2018, Weir Minerals Africa’s Senior Process Engineer, Boitumelo Zimba, said the hydrocyclones improved plant efficiency and produced 40% more tonnage than the mine’s target.

“As the Cavex hydrocyclone is tried and tested in hard-rock mining and coal classification, the Cavex 360° laminar spiral inlet profile was used as a basis for the development of a dense medium cyclone,” Zimba said. “Individual casting patterns were developed and produced in order to fabricate the Cavex dense medium hard chrome cyclone with the exact laminar spiral feed chamber that exists when moulded out of rubber.”

The customer required a solution that could offer at least six months wear-life, and a probable error of separation (Ep) of no greater than 0.08 at a cut density of 3.1 t/m³. Tracer tests were used to monitor the efficiency of the separation achieved by the Cavex hydrocyclones to ensure all of these requirements were met.

“Ep values achieved were 0.042 for the 4 mm tracer tests and 0.035 for the 8 mm tracer tests, which were below the set maximum target of 0.08 from the mine,” Zimba said. “This highlighted the benefits and improved efficiencies of the Cavex laminar spiral feed inlet.”

The lower the Ep – or probable error of separation – the more efficient the separation; it is defined as half the difference between the density at which 75% is recovered to sinks, and that at which 25% is recovered to sinks, Weir said.

“The customer’s tracer tests on the Cavex hydrocyclones showed that cut points of 3.08 t/m³ were achieved for both the 4 mm and 8 mm tracers,” Zimba said. “This was within the performance levels of 3.1 t/m³ that the customer had specified.”

Initially, the hydrocyclones were commissioned to treat only fines at the diamond plant – the minus 8+1 mm material. Later however, the mine decided to run a combined DMS, after which the full DMS size range of minus 20+1 mm was treated through all the fines DMS hydrocyclones.

“The unique design of the laminar spiral inlet geometry delivers sharper separation and maximises capacity while delivering a longer wear-life than conventional involute or tangential feed inlet designs,” Weir says. “By providing a natural flow path into the hydrocyclone body the design allows the feed stream to blend smoothly with the rotating slurry inside the chamber, reducing turbulence and improving separation efficiency.”

Zimba explained: “Combining our cone and spigot components in the hard metal range is an important contribution to the reduction in turbulence. Another vital factor is the Cavex inlet design with 360° scroll; this design was proven through extensive computational fluid dynamics analysis as well as our multiple installations to date.”

Weir Minerals also conducts ongoing research and development on methods to minimise turbulence on assembled casted components. The Cavex hydrocyclones are designed with a variety of inlet sizes to accommodate a wide top size at specified medium-to-ore ratios. The inlet sizes range from 0.2 to 0.33 as a function of the hydrocyclone diameter.

“The Cavex CVX hydrocyclone also has a wide range of vortex finder sizes to maintain separation efficiency at different operating yields and spigot sizes. The vortex finder sizes range from 0.4 to 0.5 as a function of cyclone diameter, and are designed to maintain a strong air-core at different spigot sizes,” Weir says.

To prolong life and efficiency, the hydrocyclones can also be manufactured with different materials.

“Cavex CVXA hydrocyclones are hard-wearing and are cast in 27% chromium iron for maximum abrasion resistance; components are designed for ease of maintenance, with all surfaces joined with a layer of epoxy cement,” the company says.

Weir Minerals Africa operates two foundries in South Africa – one at its Isando facility and the other at its Heavy Bay Foundry in Port Elizabeth. “This allows the organisation to cast items in-house leveraging its local foundry personnel’s knowledge, experience and expertise, ensuring that the highest standards are maintained,” Weir says.

“This approach ensures optimal life of the hydrocyclone in operation, and reduced maintenance costs by replacing worn parts in situ. It also eliminates the risk of any adverse effects on performance arising from mixing old and new hydrocyclone components. Further, safety on site is enhanced by minimising the maintenance work necessary on the installed hydrocyclones.”

Zimba said future work will include the investigation of various alloys to combat high wear rates on some of the hydrocyclone components, in particular the vortex finder and the cone sections. “This will allow longer operation and plant stability,” she said.

Sandvik OptiMine to boost safety, productivity at Vedanta Zinc’s BMM operations

Sandvik is to deliver a full OptiMine® platform to Vedanta Zinc International’s Black Mountain Mining (BMM) operations in South Africa’s Northern Cape Province.

The company will commission OptiMine for trucks, loaders and drills next year, accelerating BMM’s data-driven operation for world-class mining safety, efficiency and productivity, Sandvik said.

The OEM-independent OptiMine digital platform includes equipment/asset location tracking; planning and task management; scheduling; monitoring equipment and operations and OptiMine Analytics with IBM Watson IoT.

Andre Trytsman, General Manager, BMM, said: “OptiMine gives us end-to-end visibility and control over our underground mining operations. It was important to us to have the full scope, from scheduling to analytics, to ensure we’re optimised for the safest and most productive operation possible.

“The OptiMine platform is the next step in Black Mountain’s digital journey, delivering efficiency and increasing operational performance allowing us to unlock more value. We are excited to partner with Sandvik and incorporate the OptiMine technology into Vedanta Zinc International’s exciting digital strategy.”

Last year, Vedanta Zinc signed an agreement with GE South Africa to collaborate on digitalisation at the Gamsberg zinc project, part of the BMM operations.

Sandvik says OptiMine integrates all relevant data into one source, delivering powerful real-time and predictive insights to improve operations. It is open and scalable, providing flexibility to grow as needed, and incorporate other equipment, systems and networks, the company added.

BMM’s current operations are comprised of two underground mines – Deeps and Swartberg – and a processing plant. The Deeps shaft produces copper, lead and zinc, with silver as a by-product, and the Swartberg mine produces primarily copper and lead, with silver as a by-product. BMM is also developing Gamsberg in the Northern Cape.

Patrick Murphy, President, Rock Drills and Technologies, Sandvik Mining and Rock Technology, said: “Sandvik is proud to work with the BMM team to integrate and optimise their mining processes with OptiMine, developing a world-class, data-driven operation and accelerating their productivity and safety.”