Tag Archives: South Africa

De Beers taking major technology steppingstone at Venetia Underground

Automation, Comminution of minerals, Communications in mining, Diamond mining, Environmental, Explosives and blasting, IoT, Mine shafts and equipment, Mine ventilation, Mineral processing, Mineral project development, Mining equipment, Mining project news, Mining safety, Mining services, Mining software, Power supply for mines, Sustainable mining, Water management, , , , , , , , , , , , , , , , , ,

Making the transition from an open pit mine that has been operating successfully for 30 years to an underground operation that could become one of the most mechanised and automated in the world is not something that happens overnight.

De Beers Group embarked on the $2.3 billion underground expansion of its Venetia asset in Limpopo Province in 2012, in a move that represented the biggest single investment in South Africa’s diamond mining industry in decades.

Underground production began at the mine back in June this year, at a point when construction completion was estimated at 70%.

The introduction of autonomous mining systems performing multiple mining processes to deliver up to 6 Mt/y of kimberlite ore – for circa-4 Mct/y of diamonds – is now beginning, with a ramp-up process occurring over the next four years, according to Moses Madondo, Managing Director of De Beers Group Managed Operations.

“The technologies we are implementing – some of which are under development themselves – will be gradually phased in,” he told IM. “Where appropriate, we will take advantage of ‘proven’ technologies first to ease the change management process, before advancing to less mature technologies thereafter.

“The process should see us start operating areas of the mine in autonomous capacity by 2027.”

De Beers has engaged Sandvik Mining and Rock Solutions for its automated production machines, with the OEM delivering a 34-strong fleet made up of LHDs, ADTs, twin-boom drill rigs, roof bolters, cable bolters and production long hole drills. A further 12 units will be delivered in the future. These iSeries machines include 17- and 21-t payload LH517i and LH621i LHDs, 51-t payload TH551i ADTs, DD422i face drills, DS412i roof bolters, DS422i cable bolters and DL422i production drills.

Employee in the cab of one of the fleet of Sandvik machines

The underground mine will use sublevel caving to extract material from its K01 and K02 orebodies. Initially the ore will be hauled to surface using a combination of underground and surface haul trucks. As the operation matures, the hauling systems will transition to an automated truck loop in combination with vertical shafts for steady-state production.

Sandvik is also providing its AutoMine® system for the remote operation of loaders and trucks and its OptiMine® system for machine health monitoring, task management and location tracking.

Automation will be applied through a phased approach, beginning with manual operation and close monitoring of performance through data analytics. Automation will then gradually be introduced with the necessary training and experience in the operation and support of these technologies.

Madondo explained: “Our current fleet is made up of manually operated machines, which are optimised with automated task management. This process still requires an on-board operator, although many functions are automated.

“The next step would be autonomous machines, operated and overseen from surface, with our training centres already set up to deliver that.”

A pilot project to prepare the production team for the use of remote loading at the drawpoints and autonomous tramming to the tip is in the process of being established, with trials set for later this year and into 2024.

With sublevel cave mining, there is a risk of mud rushes and water ingress at drawpoints and remote loading will allow material to be loaded without putting operators at risk.

This pilot project will have a single loader operating under AutoMine Lite in a dedicated area on 46 Level that is isolated from other areas of the mine, with the machine controlled locally from a mobile tele-remote station just outside the autonomous operating area (ie not from surface).

An integrated operations centre on surface has been constructed and is in the final stages of commissioning.

Moses Madondo, Managing Director of De Beers Group Managed Operations

This is but a fraction of the emerging technology the company plans to employ at the mine, as Madondo highlighted.

“Of course, we will be integrating more technologies into the mix – digital mobility, data analytics, a cave management system, collision prevention, personnel alert systems, equipment location and tracking, production management through digital platforms, centralised blasting systems and digital twins,” he said. “All of these projects have people working on them to deliver our project objectives.”

For Madondo, the business case for employing such high levels of mechanisation and automation has only strengthened in the 11 years since the first shovel was placed in the ground for the underground project.

“This is a challenge with deep underground mining projects – they take a long time to develop and, in that period, technology and economics change,” he said. “It is, however, clear that mechanised mining allows you to take on these advanced technologies as the years go by.

“The investments are not just for technology’s sake. The business case must be built on our ability to improve safety and keep our people away from harm; as well as to make us more efficient and beat inflation, ensuring the margins we promised investors are realised.”

On the former, the company has partnered with Booyco Electronics on rolling out the South Africa-based company’s Level 9 – as defined by the Mining Industry Occupational Safety and Health (MOSH) organisation of South Africa – Booyco Electronics CWS850 collision prevention system at the mine.

“All of our Sandvik equipment is Level 9-enabled and we’re busy on this rollout,” Madondo said. “We’re already employing Level 7 (a system that warns pedestrians of their proximity to trackless mobile machinery) for this equipment. It’s now just a matter of getting to that new advanced level efficiently and safely.”

The company is also employing the Mobilaris Mining Intelligence platform for personnel location and situational awareness to help locate individuals in case of an emergency and notify them of incidents should they occur.

On the productivity side, the company is employing a cave management system to prevent overdrawing, Madondo says, linking the sub level caving mine plan with on-board LHD diagnostics and bucket weighing for efficiency and safety.

Process controller overseeing processing operations within the Venetia Mine

On top of OptiMine and AutoMine from Sandvik, the company is looking to integrate Howden’s Ventsim™ CONTROL system for monitoring, control and optimisation of underground mine ventilation in a ventilation on demand (VoD) application.

“We will gradually introduce VoD and Ventsim CONTROL as it allows us to 1) optimise the use of air and ventilation; and 2) retain the right condition and hygiene levels in the areas of the active mine,” Madondo said.

In an automated mining scenario, Ventsim CONTROL could potentially start ventilating an area of the mine in line with the expected arrival of the autonomous equipment, optimising the process and environment, and, as a result, reducing energy use.

Reaching the pinnacle

Also part of that discussion is decarbonisation – an area the company has already made significant progress on with its move underground.

“Transitioning from surface to underground has reset the energy balance,” Madondo said. “This has seen the site become far less reliant on energy from fossil fuel sources, with the big trucks and loaders from the pit replaced with smaller underground equipment and more electrical infrastructure.

“We predict by that, by 2030, 85% of all energy consumed will be electrical and only 6% will be diesel. That is a significant shift from the open-pit operation where nearly 85% of all energy consumed was from diesel.”

The company’s broader electrification work is currently in the review stage, but Madondo did provide some insight into the focus areas.

“We are looking at battery LHDs and trucks; we will consider trolley assist hauling loops and tethered electrical loading in some of the areas too,” he said. “It is all part of a progressive shift that will be integrated with the sourcing of renewable power for the mine.”

De Beers itself has set targets to become carbon neutral across its operations by 2030, Venetia Underground included.

The first electrification project the company is likely to embark on is a battery-electric retrofit of one of its light duty vehicles, Madondo said, explaining that this technology is relatively mature and comes with less infrastructure requirements due to the ability to charge the machines on surface.

“Our wider electrification plans are being influenced by the maturity of the technology; it may be more beneficial to wait until the adoption rate and learnings increase before we commit,” he added.

Even with the planned integration of such advanced technology at Venetia Underground, Madondo says De Beers still has some way to go to achieve the FutureSmart Mining innovation-led approach to sustainable mining that its parent company, Anglo American, advocates for.

“The pinnacle of De Beers mining expertise will probably be realised when we get to rollout our Diamond FutureSmart Mining, which ultimately is a mine design that we can use to develop future mines that make mining safer, more efficient, more sustainable and with a smaller environmental footprint,” he said.

“Of course, Venetia is certainly a steppingstone to that, but we will hopefully apply the learnings from Venetia for Jwaneng Underground (in Botswana) in the not-too-distant future. That could represent a different, more technologically advanced proposition where all processes are setup to benefit from the latest innovations.”

He concluded: “This will ensure we help create a healthy environment, that we catalyse thriving communities, and that we build trust as a corporate leader. We are shaping a future that creates shared value for all our stakeholders.”

Luna Innovations to provide conveyor heat detection monitoring solution in South Africa

Bulk handling, Equipment maintenance, Mining equipment, Mining safety, Mining services, , , , , ,

Luna Innovations Inc, a global leader in advanced fibre optic-based technology, has won what it says is a large contract to provide heat detection monitoring of 40 km of conveyor belt in 11 South African mines.

Luna’s contract is with a leading South African provider of risk-management solutions providing services to the operator of the mines.

To ensure the safety of their employees and protect their assets, Luna Innovations LIOS™ fibre optic cable and heat detection system was selected to provide a fast and reliable monitoring system. The LIOS DE.TECT linear heat detection system can monitor up to 10 km of conveyor belt and provides fast and accurate information about overheating before a fire develops, according to the company.

Conveyor belt issues are the leading source of fires and operational disturbances in the mining industry, Luna says. Belt rollers experience wear and tear over time, which can lead to overheating. Proactive detection of defective rollers and conveyor systems enables preventative maintenance that can help avoid potential hazards.

Scott Graeff, President and CEO of Luna, said: “We are very pleased to be announcing another step forward for safety systems utilising our fibre optic sensing technology. The applications for fibre optic sensors are nearly limitless and this is another great example of how our solutions are helping our customers create safer, more efficient workplaces. We are happy to add this application in the mining sector to our over 2,500 permanent installations of the LIOS sensing platform.”

The LIOS DE.TECT linear heat detection system continuously measures temperature with a resolution of 1°C or better and provides a response time of four seconds or less, according to the company. In the event of a conveyor belt fire, the DE.TECT system provides immediate, location-specific information about the size of the fire and how it is spreading so efficient fire suppression can be deployed, Luna says.

Orion Minerals to test out ITC120 continuous loader at Prieska copper zinc mine

Base metals, Energy minerals, Mineral project development, Mining equipment, Mining services, Sustainable mining, , , , , , , , , , , , ,

Orion Minerals says it has awarded a six-month trial mining contract to P2 Mining, a subsidiary of South Africa-based mining contractor Newrak Mining Group, to undertake the early works trial underground mining program at the Prieska copper zinc mine (PCZM) in the Northern Cape Province of South Africa.

The trial mining will target the +105 Level Crown Pillar, using conventional and alternative underground mining methods, including the use of an ITC120 continuous loader and two 20-t bi-directional trucks in the underground development cycle.

The trial mining will comprise 120 m of footwall ramp development, before accessing the high-grade supergene ore of the +105 block with ore development along strike for 150 m on either side of the primary access as the primary in a cut-and fill mining cycle.

In addition, the Newrak contract also covers the opening of the 143 Level historical stope draw-points for selective loading and hauling to surface of broken ore remaining in the stopes, in order to perform bulk sampling and metallurgical trials on the material. If successful, this exercise will continue to build a stockpile on surface for future processing once the concentrator plant is commissioned.

Orion’s Managing Director and CEO, Errol Smart, said: “This is a tremendously exciting period for Orion as we move to active trial mining at Prieska and start our transition from developer to operating mining company. We have spent the past two months completing essential preparations, such as installing underground refuge chambers, upgrading hoisting capacity of the emergency escapeway to surface and sourcing and installing key ventilation equipment.

“With these essential safety and environmental preparations now complete, we can finally mobilise the mining contractor to commence drilling, blasting and hauling ore to surface.

“The trial mining phase will also see Orion apply our core philosophy of bringing proven, innovative methods matched with appropriate skills and experience to our operations, while at the same time training and upskilling our host community members so that we can ultimately source our staff locally. We also aim to develop local enterprises to service Orion’s mines and the South African mining industry, encouraging our service providers and contractors to support these endeavours and contribute to the skills transfer and enterprise development.”

Orion will be testing an ITC120 continuous loader supported by two specifically paired bi-directional drive trucks at the PCZM operation. The ITC120 loader shows great promise in delivering improved cycle times and development rates compared with conventional mechanised rock loading and hauling methods, according to Orion. It is envisaged that these improvements can deliver significant a positive impact on both the +105 and the Prieska Deeps mining once dewatering has been completed.

The ITC120 continuous loader and the PAUS 20 t dump trucks are supplied via Hurst Mine Tec (HMTEC), the newly established local representative for Swiss group ITC. HMTEC is introducing the European tunnelling technology into South Africa for the first time and will support the imported equipment locally.

Orion said: “During development, the combination of the continuous loader with the two bi-directional drive dump trucks is expected to show significant improvements in safety, cycle time reduction and lowering development costs, with one machine doing all scaling, mucking and loading in a face. Direct conveyor loading into dump trucks driven into the face removes the need for shuttling LHDs and removes the requirement for loading and passing bays in the development tunnels. The bi-directional drive trucks also improve safety, removing the need for reversing long distances by LHDs. Importantly, the number of engines running is reduced, with a resulting decrease in exhaust gases and heat.”

The continuous loader and paired bi-directional trucks are anticipated to have particular application in the drift-and-fill stopes that will be prevalent in both the +105 mining block and in the shallow-dipping Prieska Deeps ore blocks, Orion added.

The anticipated improvements in development cycle time and associated cost reductions will be demonstrated during trial mining and carried forward to the revised bankable feasibility study (BFS) for the early mining start and planned future deeps mining at PCZM.

The 2020 updated BFS outlined an initial 12-year, 2.4 Mt/y operation targeting 22,000 t/y of copper and 70,000 t/y of zinc, with life of mine production slated at 226,000 t of copper and 680,000 t of zinc.

Talisman’s ProdMate evolving from its big data roots

Automation, Communications in mining, IoT, Mining safety, Mining services, Mining software, , , , , , , , , ,

“The wider mining industry might have been talking about the concept of ‘big data’ for less than 10-12 years, but it’s been on our agenda since 1988,” Chris Wilkinson, ProdMate Chief Executive Office, tells IM.

“We were the first to apply flash memory in a non-military application, at the time buying 156 kb flash drives to record data coming off continuous miners.

“We were pioneers of ‘mining’ data for improving operational performance.”

Wilkinson and his team, now within Talisman Partners under the Talisman Technical subsidiary that acquired ProdMate in early 2022, have come a long way in the 35 years since it started in the data and process improvement realm.

The company has expanded from analysis of continuous miner operation in coal mines into developing a four pillar-strong ProdMate integrated production management platform that has applications across all types of operating mines.

These make for a holistic, equipment- and mining method-agnostic platform that, when used in tandem and with an adequate change management process in place, can increase production by up to 40% within six months, according to the company.

ProdMate found its feet in the South African coal market in the late 1980s and early 1990s. Then, around 1999, a large international mining corporation came to the company looking to apply the system and change management at one of its mines in South Africa.

“They initially saw a 44% increase in production in the first year and continued driving process improvement and KPI analysis over a further three years to achieve an 80% production improvement and world-class productivity,” Wilkinson said of this mine-site installation.

Such results – with a high-profile client – put ProdMate on the map in South Africa, with around 85% of the domestic coal market eventually taking up its use.

The step-up in performance at numerous mines was also a reflection of ProdMate’s ongoing evolution, according to Wilkinson, moving from a hardware and software company to one focused on powerful software that could be applied on all equipment and mining methods, regardless of vendor.

“We soon realised that it didn’t matter how many sensors on the equipment you had feeding you data, you still needed humans to tell you things about the mining environment to provide that required operational context,” he said.

This led to the development of mobile device software to report, in real time, what the machines were doing. This has since become the ProdNote mobile device software that makes up one of the four modules within ProdMate.

A planning board followed soon after, providing an alternative to the Excel-based reporting that miners had been using. This Excel alternative creates a digital shift plan and targets that all team members can follow. Combining digital planning with machine data process analytics and actual production data, as well as task completion and downtime recorded in real time via the ProdNote mobile device software, completed the “closed loop” digital management system.

The MOS Meeting Manager was the last input to complete the puzzle: “What we felt was missing was an electronic meeting manager that could help clients track issue resolution through action tracking across the mines hierarchy of MOS meetings, making accountability and resolution of problems simpler to manage,” Wilkinson said. “Many clients implemented MOS systems but mine management were concerned that people spent too much time in meetings and not enough time supervising their core functions. We auto linked information to the correct meetings, created data analytics to help make meetings more efficient and allowed clients to track organisational efficiency.”

As it stands today, customers can pick and choose between all of these modules, integrating with any other software platforms they may be using to improve and track their operations.

“The real power of this is when you integrate it all together,” Wilkinson said. “When all four modules speak directly to each other, and to any other complementary systems, there is a clear cause and effect that allows for accelerated and effective decision making.”

It goes further than this, with an embedded digital twin allowing companies to sketch out theoretical scenarios if, for example, a critical production machine goes down.

“This digital twin keeps running and automatically updates, allowing the operation to see what effect this outage has on the mine schedule,” Wilkinson said.

All this information comes with a digital record to allow for not only regulatory reporting, but also ongoing learnings and knowledge transfer.

“At any point, shift managers can go back into the data log and carry out a post-shift review of what happened in that particular moment,” Wilkinson said. “This is priceless for new employees as they can follow the same path that resolved a similar situation last time.”

There are also integrations with the ProdMate system – think fleet management, personnel proximity, air quality station systems, etc – some more advanced applications already benefit from.

Wilkinson sees further functionality being added to ProdMate in the future, too.

“We’re no longer in the big data realm; data paralysis is a real thing and the biggest cause of falling ROI on software systems,” Wilkinson said. “We’re now all about information transfer and utilisation; making sure only valuable data gets to decision makers or analysis systems.

“I think we’re just scratching the surface with this as an industry and ProdMate will continue to evolve to integrate with new solutions that provide valuable information, not simply data.”

Murray & Roberts Cementation hits 1,000 m shaft sinking milestone at Palabora’s Lift II expansion project

Base metals, Explosives and blasting, Mine shafts and equipment, Mineral project development, Mining services, , , , ,

Leading underground mining contracting company, Murray & Roberts Cementation has achieved what it says is a remarkable milestone at the end of July 2023, successfully reaching the 1,000 metre mark on its contract to sink the 1,200 metre ventilation shaft at Palabora Mining Company’s Lift II expansion, in South Africa.

This significant feat stands as a testament to the company’s exceptional capabilities and dedication to safety, it says.

The Palabora Mining Company Lift II expansion project is a crucial endeavour for PMC, aimed at enhancing the efficiency and capacity of its operations. The 8.5-m-diameter ventilation shaft will serve the Lift II block cave and plays a pivotal role in the overall mining infrastructure.

Reaching a depth of 1,000 metres in the ventilation shaft is a major accomplishment, highlighting the expertise and commitment of Murray & Roberts Cementation in tackling complex mining projects, it says.

Fred Durand, Murray & Roberts Cementation’s Senior Project Manager, says one of the most remarkable aspects of this project is the unwavering focus on safety.

“Despite the immense challenges involved in underground mining and especially blind sinking, we have maintained an impeccable safety record throughout the Lift II expansion project,” he says. “The team’s relentless dedication to safety protocols and best practices resulted in an impressive milestone earlier this year of 574 consecutive days without a Lost Time Injury (LTI).”

He says that the achievement of this safety milestone showcases the company’s commitment to ensuring the wellbeing and safety of its workforce.

Durand concluded: “As the ventilation shaft project enters its final stages, the excitement and anticipation among all stakeholders, including PMC and Murray & Roberts Cementation, are palpable. The successful completion of this project will not only mark a significant engineering feat but will also have a profound impact on PMC’s mining capabilities.”

Murray & Roberts Cementation has aligned with the owner’s team to display technical excellence, professional management and passionate safety leadership from the day site establishment commenced in October 2019, according to Aidan Schoonbee, Senior Manager for PMC’s Lift II Construction, Concentrator and Vent Shaft.

De Beers delivers first production from Venetia Underground

Diamond mining, Mine operation news, Mine shafts and equipment, Mineral project development, Mining people, Mining project news, , ,

De Beers Group has celebrated a key milestone with the delivery of first production from underground operations at its Venetia Mine in Limpopo, South Africa. The overall construction of the underground mine is now 70% complete, with construction and production ramp-up continuing over the next few years.

Venetia Mine, South Africa’s leading diamond mine, ceased open-pit mining operations in December 2022 after 30 years of production from the Tier 1 asset. De Beers embarked on the $2.3 billion underground expansion in 2012, in what represents the biggest single investment in the country’s diamond mining industry in decades. The highly mechanised underground operation will deliver up to 7 Mt/y of kimberlite ore to produce ~4 Mct/y of diamonds.

Moses Madondo, Managing Director of De Beers Group Managed Operations, said: “The investment in taking the world-class Venetia Mine underground enhances De Beers Group’s global production for the long term and is an indication of our commitment to South Africa. Our incredible team of employees and contracting partners have pulled together fantastically to achieve this major milestone of first production from the underground operation. We look forward to seeing this high performing team continue the good work as we ramp up production over the next few years, bringing profound benefits to our workforce, our host communities, commercial partners and South Africa as a whole.”

The underground project currently employs 4,300 people, mostly from the host communities of Musina and Blouberg Municipalities. De Beers commissioned a $10.5 million training centre in June 2021 as part of its operational readiness framework to enhance the transformation of people, processes and systems for the successful transition from open pit to underground mining. To date, a total of 180 employees have successfully transitioned to underground operations without any job losses for Venetia Mine’s permanent employees.

Davra and IoTDC to pair expertise for enhanced tailings storage facility monitoring

Communications in mining, IoT, Mining safety, Water management, , , , , , , ,

Industrial IoT solutions providers Davra and IoTDC have announced what they say is a landmark partnership that merges their expertise to launch a state-of-the-art suite of software applications for the comprehensive safety monitoring of mining operations.

The announcement was made during the recent visit of the Irish Tánaiste (Deputy Prime Minister), Micheál Martin, to Wits University in Johannesburg.

This initiative builds on Davra’s established collaboration with the European Space Agency (ESA) on the Protelum project, ensuring stringent compliance with the Global Industry Standard on Tailings Management (GISTM).

The advanced software suite focuses on real-time monitoring and management of tailings storage facilities (TSFs). By harnessing the power of advanced sensors, predictive analytics, machine learning algorithms, and Earth Observation (EO) data from the European Copernicus program and other sources, the software provides early detection of irregularities and potential hazards, thereby enhancing the safety and operational efficiency of mining enterprises, the companies say.

Additionally, the suite ensures full GISTM compliance, helping mining operators align with the highest international standards for tailings management safety and integrity, they claim.

Key features and benefits include:

  • Real-time tailings monitoring: the software suite employs EO data from the Sentinel satellite constellation and IoT sensors to provide real-time insights into tailings dam stability, enabling swift detection and response to potential issues;
  • Predictive analytics and machine learning: utilising the capabilities of AI, the software predicts and prevents potential incidents by analysing behavioural trends and patterns in tailing dam operations;
  • GISTM compliance: the suite assists mining operations in achieving rigorous GISTM compliance, ensuring the utmost safety and integrity in tailings management; and
  • Enhanced operational efficiency: with continuous monitoring and AI-powered analytics, mining operations can significantly improve productivity, reduce downtime and minimise environmental impact.

“We are thrilled to announce this partnership with IoTDC during the Irish Tánaiste’s visit to Wits University,” Paul Glynn, CEO of Davra, said. “By combining our ongoing engagement with ESA on the Protelum project and our cutting-edge IoT technology, we’re equipping mining operators throughout South Africa with an unparalleled tool to manage and monitor their tailings storage facilities.”

Ewald Fourie, CEO of IoTDC, added: “This collaboration with Davra brings together our local mining sector expertise and their global IoT and space data experience to deliver a unique solution. We’re confident that this technology will set a new standard for safety and sustainability in the mining sector.”

Murray & Roberts Cementation shaft sinking alternative takes safety to a new level at PMC Lift 2

Automation, Base metals, Explosives and blasting, Mine operation news, Mine shafts and equipment, Mineral project development, Mining industry recognition, Mining safety, Mining services, , , , , , , , ,

The sinking of a 1,200 m ventilation shaft as part of the Palabora Mining Company (PMC) Lift 2 expansion in South Africa is proving to be a partnership success story, based on an unshakeable commitment to safety, according to Murray & Roberts Cementation.

PMC commissioned this new ventilation shaft – which measures 8.5 m in diameter – to service its Lift 2 block cave, awarding the project to Murray & Roberts Cementation in February 2019. Now in its final phases, the project has earned an impressive safety record; it has been fatality-free, and, last year, achieved 574 days without a Lost Time Injury (LTI), the contractor reports.

The Lift 2 project will extend mine life by more than 15 years. Originally an open-pit mine, the Palabora mine transitioned to underground block cave operations in the early 2000s when Lift 1 was commissioned. Back in February, Murray & Roberts Cementation outlined that it had recently celebrated the achievement of a major milestone – reaching the 800 m mark – at the project.

“Feasibility studies indicated that a blind sink was the optimal method, despite its higher cost and longer time frame,” Jas Malherbe, Murray & Roberts Cementation’s Project Manager, explained. “Ground conditions were among the reasons why raiseboring was not an option, as the side walls needed immediate support to prevent scaling.”

Traditionally, the shaft would be lined to within 12-18 m of the shaft bottom, with the sidewalls being temporarily supported with split sets and mesh. However, the difficult ground conditions led to high levels of scaling that made this practice unviable.

“With ground conditions being such a key challenge on the project, we responded in an innovative way by taking the shaft lining right down to the blasted face,” Malherbe says. “The shaft sinking methodology in this project is, therefore, based on the Canadian shaft sinking method pioneered by Murray & Roberts Cementation – but has been adapted to ‘the PMC way’. This has involved lining the shaft to within 1.5 m of the shaft bottom, after mucking out the waste.”

Murray & Roberts Cementation uses a specialised concrete mix for rapid setting and early strength which hardens to 3 MPa within four hours – and this would be in place for at least eight hours before blasting. This solution requires that the blast is conducted while the shutters are still in place – so the shutters are strengthened and a toe added that would better handle the blast. The exposed concrete above the shutter is able to withstand the blast, as it has already cured for 48 hours.

Malherbe explains that drilling is undertaken by two twin-boom electro-hydraulic jumbo drill rigs. These are slung down the shaft from surface and nested in the four-deck stage for drilling the shaft bottom, a procedure which is repeated for each 48 hour blast-to-blast cycle. Waste rock is lashed using an excavator with a 0.36 cu.m bucket, which is lowered from surface through the stage to shaft bottom.

After blasting, an excavator is used for loading rock from the shaft bottom, which is safer than the conventional cactus grab, according to Murray & Roberts Cementation. Ground conditions lend themselves to the generation of large rocks during blasting, which can be difficult to handle. These are broken up using an hydraulic breaker, which can be coupled to the excavator. An 11-t kibble transports the waste rock to surface.

The Lift 2 project will extend mine life by more than 15 years

“Lashing a shaft with an excavator is not a new idea, but it is usually a back-up method to the cactus grab,” Malherbe says. “In this project, we decided that the excavator would be the primary lashing method, to further enhance safety on site.”

Steps have also been taken towards automating the headgear, to avoid the safety hazards of manually hooking the kibble to tip out the waste rock. This includes the winding engine driver being able to use a camera to check for correct hooking.

“We also opted to use electric actuators in this project, rather than the traditional pneumatic and hydraulic cylinders on equipment such as the bank doors, swing chutes and tipping chutes,” Malherbe continues. “This has allowed us to mitigate the risks such as hearing loss from the noise of certain actuators, and contamination from oil leaks.”

According to Sechaba Letaba, PMC’s Package Manager on the project, PMC took a deliberate decision to prioritise safety in the sinking of this ventilation shaft.

“By taking the PMC way, we have accepted that the pace of sinking would have to be compromised,” Letaba says. “This has proved to be a positive approach, as we have an outstanding safety record on the project. This is in stark contrast to the history of shaft sinking, which would often claim lives and cause injuries. We are therefore very proud of what we have achieved to date.”

He highlights the pivotal roles played by Sam Ngidi, PMC Senior Manager Operation & Lift 2 Project, and Aidan Schoonbee, Senior Project Manager Construction – in driving the project and ensuring its success.

Fred Durand, Murray & Roberts Cementation’s Senior Project Manager, points out that unexpected challenges tend to have an impact on scheduling, so the strong relationship of trust with PMC was vital to solving any issues as they arose.

“Our approach has always been to work closely with customers on solutions, and to ensure they are regularly updated on progress,” Durand says. “As a team, for instance, we decided that the rock breaker was the right solution for the issue of oversized rocks, and it was accepted that this would have an impact on the cycle times.”

Similarly, encountering more challenging ground conditions than expected required a significant mindset change about how the team approached the project.

“With the supportive relationship between PMC and Murray & Roberts Cementation, we were able to agree on the necessary remedies and adjust the timeframe to suit our priority – which was safety,” he says.

Malherbe concludes that, for Murray & Roberts Cementation, the lessons learnt on this project have shown the industry a viable alternative method of shaft sinking that takes safety to a new level.

JUWI’s renewable rollout in South Africa continues with Sibanye-Stillwater deployment

Environmental, Mining services, Power supply for mines, Precious metals, , , , , , , , , ,

JUWI Renewable Energies, a leading global solar, wind and hybrid project developer, EPC (engineering, procurement and construction) and operations and maintenance company, has announced that it has 400 MW of EPC projects in advanced stages of development for mines in South Africa.

The news follows the financial close of the 89 MW Castle Wind project by the African Infrastructure Investment Managers (AIIM) Consortium for Sibanye-Stillwater’s mining operations, a project initially developed by JUWI for the South African government’s Renewable Energy Independent Power Producers’ Programme (REI4P). The AIIM Consortium included African Clean Energy Developments as developer and Reatile as investment partner.

“We’re seeing a wave of formal requests for renewable energy projects from South African mines, largely driven by the energy crisis, commercial considerations and decarbonisation targets,” Richard Doyle, Managing Director, JUWI SA, said.

“The right regulation has been needed to translate this demand into actual projects for mines. The amendments to the licence-exemption threshold and ability to wheel electricity are now allowing us to pivot projects initially developed for REI4P, such as the Castle Wind project, into the private sector, making them a reality. This is a significant milestone for our team of experts who work tirelessly to advance the renewable energy transition in Africa.”

Wheeling is the act of transporting electricity from a generator to a remotely located end-user through the grid. With most large mines and energy users in South Africa lacking land for large-scale wind and solar projects, the ability to wheel electricity is essential for self generation, according to JUWI.

Chris Bellingham, Head of Project Development, JUWI, explained: “The ability to wheel power through the network combined with the far lower electricity tariffs of solar and wind projects, incentivises mines to either remotely generate their own electricity or purchase it from remote independent power producers, thereby sourcing generation from sites where the resource is stronger. This is a real win for mines, allowing them to save costs, reduce greenhouse gas emissions, and when used in combination with backup technologies, avoid load shedding.”

Sumeet Ramandh, the project’s Development Manager, said  JUWI initiated the Castle Wind project in 2011 and, although there were extensive delays with the government’s procurement process, it remained dedicated to transforming the site into a notable renewable energy asset for South Africa.

“With the recent regulatory improvements, JUWI took the decision to sell the project to the AIIM Consortium, which secured an Eskom agreement to wheel energy from the wind farm to power Sibanye-Stillwater’s mining operations,” he said.

At the start of the year, JUWI reported that it had 4 GW of renewable energy projects in various stages of development across Africa, with another 1 GW to be initiated in 2023. The company also recently signed an EPC agreement with Pan African Resources to construct a 8.75 MW solar plant for the its Fairview mine.

Murray & Roberts Cementation hits the accuracy mark on Platreef ventilation shaft development

Explosives and blasting, Mine shafts and equipment, Mineral project development, Precious metals, , , , , , , , , , ,

Murray & Roberts Cementation is helping Ivanplats deliver the Platreef project in South Africa through the provision of drilling services at the ventilation shaft.

The dual purpose use of the new ventilation shaft at Ivanplats’ Platreef project required extreme pilot hole accuracy, according to Murray & Roberts Cementation.

The vent shaft, or Shaft 3, which meets horizontal development at a depth of 950 m, also needs to be equipped with a hoist and rope guides to carry personnel in the case of emergency. The rope guides for the hoist require the shaft to be drilled vertically within tight parameters. According to Dirk Visser, Senior Project Manager at Murray & Roberts Cementation, this meant offering the client minimal deflection of the pilot hole using a continuous steering tool.

“Using the well-proven German-designed-and-manufactured Micon, Rotary Vertical Drilling System (RVDS), we were able to achieve the set parameters required for a rope guide installation,” Visser says. “The worst deflection was no more than 0.05% – or 452 mm – and, by the time we bottomed out, the deviation was only 0.02% or 226 mm off centre over a final drilling depth of 950 m.”

Micon’s specialised RVDS is a continuous self-steering tool working on a close loop system which steers the tool using two-axis gyro inclination sensors that activate the hydraulic steering system. It can determine in real time if there is any deviation from the vertical course, and communicate this information to the operator on surface via pressure waves in the drilling water by converting the pressure waves into information through transducers, according to the company.

The Murray & Roberts Cementation drilling team not only ensured accurate directional results, but also optimised the performance of the RVDS. By keeping an eye on key variables like voltage levels and water cleanliness.

Visser highlights that drilling to these tolerances with this highly technical equipment demands a very experienced team. On this project, for instance, the most ‘junior’ person has worked with the RVDS for 15 years, while another member has 28 years of experience in raiseboring.

Platreef is owne 64% by Ivanhoe Mines. A 26% interest is held by Ivanplats’ historically disadvantaged, broad-based, black economic empowerment (B-BBEE) partners, while a Japanese consortium of ITOCHU Corporation, Japan Oil, Gas and Metals National Corporation, and Japan Gas Corporation, owns a 10% interest in Ivanplats.

In May, Ivanhoe Mines said that underground development work had been focused on the vertical development of waste passes between the 750-m, 850-m and 950-m levels, and lateral development towards the orebody, as well as lateral development required for underground infrastructure on each level including access to the bottom of Shaft 3 on the 950-m level. Shaft 3, with a diameter of 5.1 m, is currently being reamed with approximately 150 m of 950 m completed to date, it said. Planned completion was scheduled for the December quarter of 2023.

Platreef’s commercial production is expected in 2024, with Shaft 2 now expected to be commissioned in 2027. The initial scope of the phased development plan is to fast-track Platreef into production, starting with an initial 700,000-t/y underground mine using the existing Shaft 1 and a new on-site concentrator. Platfreef, Ivanhoe says, is projected to be Africa’s lowest-cost producer of platinum-group metals, nickel, copper and gold.