Tag Archives: De Beers

Murray & Roberts Cementation continues to boost mining reputation in southern Africa

Murray & Roberts Cementation continues to add to its order book of business in southern Africa, with the company saying it is engaged in a number of projects in South Africa and having project prospects in nearby countries.

According to Graham Chamberlain, New Business Director at Murray & Roberts Cementation, the busy pipeline of projects demonstrates the mining sector’s faith in the company’s industry knowledge and depth of skills. In southern Africa, the main projects underway are at De Beers’ Venetia Mine, Ivanhoe Mines’ Platreef project and Palabora Mining Company.

At the Venetia Underground project near Musina, work has been ongoing since 2013 in one of the largest investments in South Africa’s diamond industry in decades. Transitioning from open-pit to underground mining will extend the mine’s life until 2046. Murray & Roberts Cementation has been engaged in sinking, lining and equipping of two shafts – the production and service shafts – to a depth of 1,080 m. The company also developed a decline tunnel and is completing associated surface and underground infrastructure, in a project whose scope included raiseboring work to establish ventilation infrastructure.

“In this maturing project, the mine is now getting into ore and starting to develop the infrastructure levels,” Chamberlain says. “At the shaft bottom, good progress continues to be made with the construction of workshops, pumping stations, silos and loading arrangements.”

Murray & Roberts Cementation is also conducting all the infrastructure development at Ivanhoe Mines’ Platreef project near Mokopane. This includes the sinking of a 5.1 m ventilation shaft to meet horizontal development at 950 m below surface. To achieve the high accuracy levels demanded by the project, the raiseboring equipment was guided by directional drilling technology.

“A unique aspect of this project is that the shaft will be hoisting ore at that same time as allowing upcast air to reach surface,” Chamberlain says.

Another vent shaft by Murray & Roberts Cementation – measuring 8.5 m in diameter and reaching a depth of 1,200 m – is nearing completion at Palabora Mining Company near Phalaborwa. Part of the mine’s Lift II expansion, the project has earned an impressive safety record – being fatality free and achieving 574 days without a Lost Time Injury since 2022. Ground conditions were among the reasons why a blind sink was chosen as the optimal method instead of raiseboring, as the side walls needed immediate support to prevent scaling.

“We also have a number of services projects underway related to raiseboring, grout plants and rehabilitation,” Chamberlain explains. “Much of our work in this field is focused on old infrastructure that requires maintenance, repairs or upgrades; we also conduct extensive vertical work in ore passes and silos.”

The company carries out vital rehabilitation in ore passes where ground conditions have deteriorated to prevent ore from moving smoothly – thereby risking production targets. Innovating safer techniques for this work, Murray & Roberts Cementation has developed the tube-and-fill method, first applied about seven years ago at an underground platinum mine in South Africa. These installations are also expected to outlast the lifespan of an ore pass rehabilitated with traditional shotcrete.

“On the engineering front, we continue conducting rebuilds of underground mining equipment at our Bentley Park facility near Carletonville,” Chamberlain says.

He highlights the work of the company’s design department, which remains extremely busy with feasibility studies associated with vertical work. With the renewed interest in commodity segments like copper, there is also previous work that customers are asking Murray & Roberts Cementation to review and update.

Training in underground mining and related skills at the company’s Training Academy on Carletonville continues to empower many thousands of learners each year, Chamberlain points out. This skills development is done on behalf of clients, as well as for the company’s own requirements.

“At any one time, we can host about 420 learners, and we are generally at full capacity,” he says. “We have just recently upgraded these facilities to further enhance training technologies that allows learning to take place safely but in a realistic environment.”

In compliance with many African countries’ localisation regulations, Murray & Roberts Cementation has registered companies in eight countries in the Southern African Development Community – most of which have seen the company active with raiseboring. Chamberlain notes that there are specific opportunities in Zambia that the company hopes to capitalise upon in the near future, and is encouraged by the mining sector’s progress in countries like Namibia and Botswana.

Debswana board approves ~$1 billion investment in Jwaneng underground diamond project

The Board of Debswana, the 50:50 diamond mining joint venture between De Beers Group and the Government of the Republic of Botswana, has announced approval of the investment for a key development phase of the Jwaneng underground project, paving the way for one of the world’s most valuable diamond mine to transition from open pit to underground operations.

The circa-$1 billion investment in this phase of works, known as the Exploration Access Development Phase, is for establishing a drilling platform to facilitate comprehensive sampling of the kimberlite pipes, delivering the early access decline for the underground mine and developing essential infrastructure to support forthcoming stages of the project.

The initial works, to start in May 2024, follow the successful completion of feasibility studies.

Following the Exploration Access Development stage, the project will be developed in two further phases, Phase 1 mining and Phase 2 mining, to support long-term future production at the mine in an environment of tightening long-term diamond supply.

De Beers Group CEO and Debswana Deputy Board Chairman, Al Cook, said: “Jwaneng stands proudly as the world’s greatest diamond mine. It is a central pillar of both the Botswana economy and the De Beers Group business. The global supply of natural diamonds is falling, so moving forward with the Jwaneng Underground Project creates new value for investors, brings new technology to the country, creates new skills for our workforce and provides new gems for customers around the world. This investment is aligned with our strategy to prioritise investments in the highest quality projects. We are proud to work in partnership with the Botswana Government in creating a bright future for Debswana.”

Since 1982, when the Jwaneng Mine started operating, it has produced an annual average of almost 11 Mct/y. Currently the mine employs 2,100 permanent employees and 3,200 contractors. Pending relevant future Debswana Board approvals, the Jwaneng underground project will ensure a long-term future for the mine while creating new jobs in Botswana and ensuring Debswana continues to make a significant contribution to Botswana’s economy, De Beers says.

Woodsmith-MTS-Anglo

Anglo American lays out 5 Mt/y Woodsmith polyhalite plan ahead of full design review

This week, Anglo American hosted an investor and analyst day at its in-development Woodsmith project, in the UK, with several key technology takeaways cropping up from an in-depth presentation from Tom McCulley, CEO, Crop Nutrients.

In reviewing progress and the past, McCulley stated that Anglo has decided to start Woodsmith as a 5 Mt/y operation, with a staged ramp-up planned to the 13 Mt/y rate. The plan to sink 1,600 m production and service shafts, establish a mechanised mine, construct the 37-km-long underground tunnel and build a materials handling facility with priority access export facilities remain part of this. The potential to phase ventilation & production level development within the underground mine, potential to phase conveyor upgrades in the underground tunnel and the potential to carry out a phased expansion as required for the export facilities are all options for the 13 Mt/y blueprint.

This change has required some of the scope to go back to study phase – hence the reason why Anglo has been mooting detailed design reviews and non-critical path studies – looking at how to optimise investment and modularise the construction to get maximum value from each phase, McCulley said.

“I feel far more comfortable today about how we are setting up the project for the long-term success but managing in a capital efficient way,” McCulley said during his presentation.

Some of the elements keen observers have been watching at Woodsmith are related to mechanised underground development – both vertical (via shaft sinking) and horizontally (via tunnel boring machines (TBMs) for the 37-km-long tunnel).

TBM-led tunnel transformation

In terms of the latter, Anglo American is soon expecting to set a World Record for the longest TBM tunnel developed by a single TBM. This is currently set at 25.8 km, with the Woodsmith team having already reached the 25-km (25.3 km) mark.

“Beyond this we will pass our next intermediate shaft at Ladycross, where we will take a 3-4 month maintenance pause as we set up the TBM for the final push to 37 km, and we expect to reach the Woodsmith mine in late 2026,” McCulley said.

The machine used at Woodsmith is a Herrenknecht hard-rock TBM that, McCulley says, works similarly to the Shaft Boring Roadheaders (SBRs) being used for shaft sinking (more on that soon) in that it cuts the soils, without blasting, and the material is transported through the machine and out of the tunnel via a conveyor that is part of the TBM.

“In addition to excavating the material, the TBM also simultaneously lines the tunnel via pre-cast concrete segments (six segments make up a ring around the circumference of the tunnel); these concrete segments are fabricated at the Teesside port by a project dedicated facility,” McCulley said.

He said in every measure the tunnelling on the project to date has been an amazing success, aided by a solid team performance. This team is made up of contractors from Strabag, Herrenknecht and Anglo’s in-house personnel.

Progress has been aided by consistent ground conditions across the tunnel within what is called Mudstone strata, McCulley said.

“These conditions are very predictable and cutting is easy for the machine which minimises the bearing wear, which is a key risk area for the TBM,” he said. “This consistent strata has allowed us to switch our strategy from three TBMs to one TBM for the entire 37 km, which means we will not only pass the World Record, but we will also smash it when we reach Woodsmith in late 2026. This reduction in TBMs had a knock-on impact of saving significant capital over what was originally planned.”

Anglo is consistently seeing average rates increase to over 20 m/d and trending closer to 25 m/d, which compares favourably with about 16-17 m/d in late 2021.

Tom McCulley-Anglo American
Tom McCulley, CEO, Crop Nutrients

SBRs on the up

Mine development via TBMs is relatively proven when compared with the use of Herrenknecht SBRs for shaft sinking in mining, with Woodsmith representing only the third deployment of the technology in mining following Jansen (BHP) and Nezhinsky (Slavkaliy).

Anglo has two SBRs on site at Woodsmith, sinking the production and service shafts at the project. Redpath, which carried out the shaft sinking work at Nezhinsky, is steering developments at these two shafts, in addition to the material transport system shaft. Only the much deeper production and service shafts are being sunk via mechanised means with the SBRs.

Overseeing this and all developments at the operation is Worley as an engineering, procurement and construction management contractor.

Sinking of the service shaft began in September-October 2022, followed some six months later with activities at the production shaft. McCulley said these two were now around 550-m deep and 340-m deep, respectively.

“We typically see more daily meters from the production shaft due to the service shaft lessons being applied to the production shaft, so I’m excited as I think we may have a race to polyhalite!” he said. “We are very pleased with the progress made on both shafts since Redpath started sinking in 2022.”

On the advantages associated with using SBRs, McCulley said: “Some of the primary benefits of these machines is they are inherently safer than traditional sinking. They also eliminate the need for explosives, which is a huge benefit to us with the community as we don’t encounter noise complaints experienced in other mines. I expect these machines to be the future of shaft sinking. They are just safer, quicker and more predictable.”

The SBR is generally working in autonomous mode for most of the time following a program with pre-set parameters for cutting, according to McCulley, who said the company is expecting an average rate of 1 m/d in each shaft over the full 1,600-m length of the shafts.

“This 1 m/d includes all routine maintenance and what we call non-routine work, like installing water cubbies for pumping water out of the shafts, probe drilling, tubbing and grouting,” he said.

“Ultimately, this is the right machine for the job at Woodsmith and the cutting rates we achieve are 1.5-2 times what we would do with traditional methods.”

Looking at current sinking progress and plans to hit the orebody in 2027 in the service shaft (with the production shaft being six months behind that), McCulley pointed out a 250-m section of sinking in Sherwood Sandstone, which the company expects to reach next year.

“This 250 m of strata will see our rates reduced from our 1 m/d to something between 0.5 m and 0.75 m a day, and this will impact us for most of next year and early 2025,” McCulley said. “Once through that strata, we do not expect any further issues with the ground conditions significantly impacting production.”

The Sherwood Sandstone is characterised as a strata of highly competent rock, about 120 Mpa, according to McCulley, which is at the top end of the SBR rock hardness capacity given by Herrenknecht.

In addition to the hardness, this strata has the potential for some water fissures (ie cracks in the rock with high pressure water), according to McCulley.

“The good news for us is we hit a 2.5-m layer of this material a few weeks ago and we learned from this that we need to make some adjustments to our cutter heads and cutting picks, and now we are far more prepared than we would have been otherwise,” he said. “We are also prepared with alternative plans, including potential use of lasers, plasma blasting and/or microwaves if needed, but we expect our updated cutter head and next generation picks, developed by Element 6 of De Beers, will cut through the rock at the rates I previously mentioned. In addition, to the hard rock, this strata has a risk of high-water flows in small sections of the strata so we will need to seal the shaft via grout from the shaft. This means as we come across water, we will inject chemical grout into the fractures to block water bearing cavities and control water inflow.”

Adding to McCulley’s confidence is the fact that the nearby Boulby mine encountered the same strata some time ago, which that team progressed through via the same exact grouting technique Woodsmith is planning today.

In terms of priorities for 2023, McCulley said the team expected the service shaft to be between 650-700 m at the end of the year, versus the current circa-550 metres today, whereas the production shaft could reach 450 m by this point.

“Both shafts, if they hit the numbers noted will exceed our planned targets for the year,” he said.

“The MTS shaft and Ladycross shafts are both sunk, and we are working to fit them out during the remainder of the year. In the tunnel we have driven 4.3 km this year, we are at 25.3 km and we expect to reach 27 km, which is our stretch target for the year.”

For 2024, while Anglo continues to work through the studies, it doesn’t see any changes to its plans right now and still expects to be around the $1 billon capex number for the next few years.

McCulley added: “Our vision at Woodsmith with regards to technology is to ultimately develop a peopleless underground mine, where operations and maintenance are all controlled from the surface. This is a journey, but many technologies are already out there, we just need to put the system in place and the wherewithal to help the vendors take the next step. This will not happen from the start, but with our vision and with the team we have in place, I have no doubt that in the future this vision will become a reality.”

When at full production, Woodsmith will be a FutureSmart Mine with all the modern technologies, according to McCulley, with these characteristics ensuring the company has a low cost, high volume mine for many years to come. Continuous miners are expected to be used in a room & pillar mining application, combined with mine cars, shuttle cars or conveyors.

“On top of the mining/processing technology, I see some interesting parallels with the farming industry. They are rapidly adopting technologies, and we are very well placed to support this transition in areas like sensing, scanning, AI, etc. I think with our Anglo American Woodsmith project experience in technology we are uniquely positioned to help support this transition in farming and this is something that will have added value to our product for years to come.”

Japie du Plessis to lead Murray & Roberts Cementation

Underground mining contractor, Murray & Roberts Cementation, has named Japie du Plessis as Managing Director Designate, taking up the MD position on March 1, 2023.

Du Plessis will succeed the current MD, Mike Wells, who retires at the end of February next year.

Wells’ retirement will mark the end of a career in mining spanning 39 years. After studying Mining Engineering at Wits and graduating in 1981, he spent the first 10 years of his career working for the gold division of Anglo American at the Elandsrand (now Kusasalethu), TauTona and President Brand gold mines.

He joined Cementation Africa in 1994, a company which was subsequently acquired by Murray & Roberts in 2005 and merged with its existing mining contracting arm, RUC, to form Murray & Roberts Cementation.

His move to Cementation brought him into project work and in particular the sinking of the 3-km deep, 9-m diameter twin shafts of the South Deep gold mine, representing, at the time, the biggest shaft sinking contract ever agreed anywhere in the world. The project extended over nine years from start to finish, with Wells acting as Project Manager for part of this period, which he regards as one of the highlights of his career.

While engaged on the project, Wells was involved in devising and constructing a concrete plug to seal off a major water intersection encountered during shaft sinking. A technical paper he wrote in on the methodology adopted earned him the Association of Mine Managers Gold Medal for the best paper of the year in 1997.

After successively serving as Senior Projects Manager, Project Executive and Technical Director, Wells was appointed MD of Murray & Roberts Cementation in 2017. Over his tenure, the company has gone from strength to strength, confirming its status as one of the world’s leading mining contracting organisations, it said. A particular achievement that he takes great pride in is the company’s safety record – it has now gone eight years without a single fatality and recently celebrated six million fatality-free shifts.

In du Plessis, Murray & Roberts Cementation has found a successor to Wells with a similar depth of technical and management expertise, it says.

A Mechanical Engineer, he has spent most of his career in mining. His first assignment after graduating was at Anglo American Platinum’s Amandebult mine, where he worked his way up to the position of section engineer. He then left for a two-year stint with a sugar company in Mpumalanga before joining Murray & Roberts Cementation in 2008. He has been with the company ever since.

Contracts he has been involved with over the years he has been with Murray & Roberts Cementation include Paardekraal 2 shaft and Impala 20 shaft, both in the platinum sector, the Wessels manganese mine, the Booysendal platinum mine and the Cullinan diamond mine. Positions he has occupied include Site Engineer, Contracts Engineer, Senior Project Manager, Engineering Manager and Project Executive.

Over the past seven years, he has had special responsibility for the Venetia Underground Project (VUP) of De Beers, one of Murray & Roberts Cementation’s flagship contracts.

Du Plessis was selected by a panel within Murray & Roberts Cementation that considered both external and internal candidates.

“He was by far the best qualified for the position,” Wells said. “His experience is second to none and he has mining contracting in his DNA. The fact that he is an internal candidate is a further advantage as he has a thorough understanding of how the company works and the culture that drives it.”

Looking ahead, Du Plessis says one of his prime objectives will be to extend the company’s African footprint as the majority of its work is currently in South Africa (although it does have raiseboring contracts in progress in Zambia, Tanzania and Burkina Faso). He will also work to ensure that it stays at the forefront of the move by the mining industry towards ‘green’ mining, digitalisation and automation.

Murray & Roberts Cementation is the African arm of Murray & Roberts’ global mining platform, which also includes operations in the Americas and Australia. The platform is headed by Mike da Costa, who is based in Perth in Australia.

Concor to construct new pollution control dam at Venetia Underground Project

Leading South Africa-based, black-owned contractor Concor is engaging on a 17-month project to construct a new pollution control dam at De Beers’ Venetia diamond mine, South Africa’s largest diamond producer.

The well-advanced Venetia Underground Project (VUP) will extend the mine’s life span to at least 2045, and the new dam – Pollution Control Dam 3 (PCD3) – is the main containment facility in its Storm Water Management Project (SWMP). The SWMP is a key part of the mine expansion, ensuring compliance with the Government Notice R704 on the protection of water resources, preventing the possibility of flooding and ensuring the safety of people working in the new underground mine.

Concor Operations Executive, Christo Schoeman, explains that PCD3 will cover some 27 ha to the west of the mine and will be constructed to a maximum height of 13 m. This will equip the facility to hold over 1 million cu.m of water. The water will emanate from upstream catchments including runoff from the adjacent coarse residue deposit and fine residue deposit, as well as potential overflow from the other upstream water containment facility. It will also contain water that has been pumped out the of mine’s open-cast pits and the VUP underground workings.

“Zero harm to our employees and the environment whilst executing our projects remains our principle objective,” Schoeman says. “In order to prioritise these endeavours and ensure that construction work does not impinge on the mining operation itself, among the first tasks required will be to secure the works by installing a new security fence, and upgrading the existing access road to our temporary site facilities which will ensure optimised access to our site and help streamline our workflow.”

As part of the bulk earthworks operations, the topsoil over the dam area will be stockpiled during the excavation operations, to be used later for slope protection and to ensure the regrowth of flora once construction is completed.

“In line with environmental requirements and legislation, the excavated structure will be lined with am HDPE geomembrane to prevent any seepage into the groundwater system,” he says. “A specialised service provider will supply and install the lining.”

Concor’s scope of work includes the construction of a pump station and dam spillways, as well as the installation of a 2.5 km return water pipeline to the mine’s processing plant. This will allow significant volumes of water to be efficiently recycled and re-used in processing, it says.

Schoeman highlights that the project contains a strong local procurement, employment and skills development component. He notes that Concor has always been committed to local enterprise and skills development initiatives in the areas where it undertakes projects.

“We are working closely with our client to source general workers and suppliers locally, who we will, where necessary, upskill with training, supervision and mentoring,” he says. “Certain aspects of the project can be subcontracted to these local enterprises, following the systematic process of identification and engagement.”

Concor supervises the work of subcontractors closely as part of its enterprise development commitments, he notes. Combined with dedicated mentoring, this ensures not only a quality outcome in each deliverable, but also higher levels of sustainability amongst subcontractors once the project is complete.

De Beers taps Sandvik expertise for Venetia underground diamond mine transition

De Beers Group has ordered 19 units of high-tech equipment from Sandvik Mining and Rock Technology for its Venetia Underground Project (VUP), in South Africa.

According to Simon Andrews, Managing Director at Sandvik Mining and Rock Technology Southern Africa, the company will supply a range of intelligent equipment including LHDs, ADTs, twin-boom drill rigs, roof bolters and cable bolters. Amongst the advanced models are the 17 t LH517i and 21 t LH621i LHDs, 51 t TH551i ADTs, DD422i face drills, DS412i roof bolters and DS422i cable bolters.

Partnership will be the watchword in the technological collaboration between the global diamond leader and mining OEM.

South Africa’s largest diamond mine, Venetia has been mined as an open pit since 1992. De Beers Group is investing circa-$2 billion to start mining underground from 2022, extending the mine’s life beyond 2045. The VUP represents the biggest single investment in South Africa’s diamond industry in decades, according to the company.

Allan Rodel, Project Director of the VUP, says the use of new technology is critical in building the mine of the future and will ensure the safety of its people, as well as create unique employment opportunities.

He adds that the successful implementation of this technology holds the key to further improve the mine’s productivity and cost effectiveness, enabling the quality and accuracy required for precision mining. This will also provide real-time geospatially referenced data that supports digitalisation of processes and provide a wealth of data for analysis and continuous improvement.

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’s Andrews said: “As important as the equipment itself is, De Beers Group was looking to partner with a company who would support them through the VUP journey. Taking a mine from surface to underground has many challenges, including the change in operational philosophy.”

Andrews highlighted that change management processes are as crucial to success as the capacity and performance of the mining equipment. The implementation of the new technology is seldom a straightforward process, and always requires a collaborative effort.

“The expectation of the customer is for a strong relationship with a technology partner who will help them to apply, develop and fine-tune the systems they need, over a period of time,” he says. “This way, the technology is assured to deliver the safety, efficiency and other positive results that the new mine will demand.”

Andrews believes Sandvik Mining and Rock Technology leads the pack from a technology point of view, having introduced its intelligent i-Series machines to enhance remote operation capability. This advanced range combines automation with data management capacity, aligning with the philosophy that De Beers Group has applied to this world-class operation, which prioritises the safety of its people.

Also included in the package for VUP is the Sandvik OptiMine® control system which enables continuous process management and optimisation, focusing on key areas such as face utilisation and visualisation of the operation in near real time. Using data generated by the i Series machines, OptiMine helps mining operations to achieve the lowest operating costs and highest levels of productivity.

Andrews noted that Sandvik Mining and Rock Technology is not new to the Venetia site, having worked with Venetia’s surface operations for some years, providing tools for drilling as part of a performance contract.

“We’ve been following the VUP with great interest and were ideally placed to contribute as we have extensive South African experience with mining customers in transitioning from opencast to underground,” he said. “This has involved providing equipment, implementing the systems and getting a full operation running with the latest equipment.”

He added: “Sandvik Mining and Rock Technology has successfully completed numerous large and ambitious projects, and it reflects our experience in applying automation technologies from first principles. The learnings from these projects will be seen in the VUP as the mining systems are rolled out. We will take the very latest technology and assist the mine to implement it in an underground environment through a collaborative approach using local skills and supporting it from a local base of expertise.”

He emphasises that the automation will be applied through a phased approach, beginning with manual operation and closely monitoring performance through data analytics. Automation can be gradually introduced with the necessary training and experience, ensuring consistency of operation which is the key to success.

“This will allow costs to be driven steadily lower, using the data from the operation of the fleet to guide the transition to automation,” he says. “We will work with the mine to introduce automation and further data management as work progresses deeper into the mine, and as mine employees become more comfortable with this way of working.”

Sandvik Mining and Rock Technology (soon to be Sandvik Mining and Rock Solutions) is geared to support the trackless systems implemented at the mine through the full lifecycle of the machines by supplying spare parts, tooling and components from an on-site Vendor Managed Inventory stockroom and its other South African based facilities.

De Beers contracts Redpath for mining services at Venetia diamond mine

Redpath Australia and Redpath Mining Africa have announced the award of the mining services contract at the Venetia Mine, in South Africa, from De Beers Group.

Venetia is South Africa’s largest producer of diamonds, and is situated close to the town of Alldays in the Limpopo province.

The contract comprises Redpath providing skilled management, operational and maintenance personnel to form part of the Integrated Operations Team at Venetia. The Venetia Underground project involves the transition from an open-pit mine to an underground mine. Open-pit mining at Venetia is likely to run until 2021, with the underground mine set to extend the life of the mine to 2046 and provide an estimated 94 Mct of diamonds.

Redpath Australia Managing Director, Gavin Ramage, said: “We are excited to be working with De Beers Group in transferring our safe and efficient operating processes to the South African workforce. Together with Redpath Mining South Africa, we will utilise the skillsets of both our Australian and African business units.

“Redpath have been successful in doing this at other major projects across the globe so we look forward to providing another successful outcome for De Beers at Venetia.”

Work on-site will commence in February 2021, with recruitment to commence shortly, Redpath said.

Worley out to help miners on their open pit to underground mining transition

As open-pit mines reach their economic end of life, mine owners are considering the viability of transitioning their open-pit operations to underground.

Drawing on its deep level mining expertise in South Africa, Worley helps mine owners around the world to explore the feasibility of underground life of mine extensions and identify the most efficient and safe underground mining methods.

Among the driving factors in the transition to underground mining are declining ore grades, deeper ore deposits, and an increase in demand for minerals required for the global energy transition, such as copper, lithium, manganese and nickel, Worley says.

“Worley’s centre of excellence for copper in Chile has been supporting open-pit copper mine customers for nearly three decades,” the company said. “The company is gearing up its underground capability as these mines shift their operations to below surface to access deeper ore reserves.”

Going deep in South Africa

Worley’s South Africa operations is one of the company’s mining centres of excellence with niche experience in deep level mining.

Mining has been the mainstay of South Africa’s economy for well over a century, and a major source of employment as well as foreign investment. Consequently, Worley has grown its South Africa mining team in one of the best mining environments in the world, with a collective experience of over 120 years in deep level mining and process expertise.

Robert Hull, Vice President for Mining, Minerals & Metals in Africa, says Worley’s South African operation is recognised for its deep level shaft experience, and the company also has experience across most commodities including base metals, coal, platinum, gold, diamonds and ferrous metals.

Hull says Worley has a strong global workshare philosophy and culture of collaboration. The specialist skills in South Africa gained from working on some of the biggest underground projects in the world are an integral part of Worley’s mining, minerals and metals global project delivery offering.

Deep level mine skills

Some of South Africa’s specialist deep underground skills include shaft design, ventilation and refrigeration shafts, high pressure pumping, and deep level hoisting.

Worley says it is one of the few companies in the world that has the expertise to design hoisting systems for mass hoisting, such as at the Venetia Underground Project, which will hoist approximately 6 Mt/y of rock.

The De Beers Venetia Mine in South Africa is the biggest source of rough diamonds in the country, according to Worley. The mine is in the process of transitioning from open pit to underground, to extend its life by some 25 years.

As engineering procurement and construction management contractor for South Africa’s largest mining execution project, Worley is using 3D designs for the project infrastructure to provide 3D models for the entire project’s surface and underground infrastructure, it said.

Intelligent mines

Hull says Worley is leading the way in developing digital solutions for the planning, design and execution of mining projects, with the South Africa office having played a key role in the design and development of much of the group’s digital technology in mining and minerals processing.

Hull (pictured) cites the Wafi-Golpu (owned by Harmony Gold Mining and Newcrest Mining) feasibility study update, in Papua New Guinea, where the South Africa team drew on SmartPlant design technology, which uses rapid prototyping and Building Information Modelling. The technology allowed the entire project team to visualise project objectives as never before, greatly improving operational efficiency in a dynamic time and cost-saving environment, according to Worley.

The Wafi-Golpu project is ranked as a world-class deposit in terms of its size and the grade of gold and copper within it. If developed, it will be the largest, deepest and most complex underground mine in Papua New Guinea, with a mine life of 28 years, Worley says.

Integrated project delivery teams

Worley’s South Africa team is also supporting its Australia counterparts to project manage the delivery of the deepening and expansion of an underground gold mine. This includes construction of a 1,460 m shaft, additional capacity in the processing plant, and supporting infrastructure to enable profitable recovery of ore at depth to 2 140m below surface. IM understands the project in question is the Newmont-owned Tanami Expansion 2 project, in the Northern Territory of Australia.

Mega machines for mega mines

Hull says every underground project Worley has executed has drawn on the company’s large material handling capabilities.

“In South Africa, we have a dedicated materials handling department that has the latest tools including discrete element modelling and finite element analysis, and advanced simulation tools for conveyer design,” he said.

Coenie Mynhardt, Winder Engineering at Worley, adds that mine payloads have increased dramatically in the last two decades in pursuit of higher productivity rates. Mines such as Impala and Phalaborwa, in South Africa, with an approximate 12-t per skipload, were considered ‘mega mines’ in their day. The mines of the future are more than double that size.

“The mega mines of the future need mega machines to be able to handle such big payloads,” Mynhardt says. “Materials handling technology for such deep, high tonnage operations will test current technology for capacity and reliability to bring the ore from the production levels to surface. We have the skills and expertise to find the solutions to these challenges.”

Global project delivery

“Countries such as Chile have immense potential for transitioning from open pit to underground if the geology supports it,” commented Hull. “With the wealth of experience across locations and over 4,000 staff in our mining, minerals and metals business line, we can safely and successfully deliver our customers’ underground mine assets through collaborative development of the mine and associated infrastructure anywhere in the world.”

ABB to energise world’s largest advanced diamond recovery vessel

ABB has won a contract from Damen Shipyards Group to deliver an advanced power system for Debmarine Namibia’s custom-built diamond recovery vessel.

The Switzerland-based company will supply an integrated power system package that will ensure the world’s largest and most technologically advanced diamond recovery vessel meets exceptional safety, efficiency and availability requirements, it said. The vessel is being built by Damen at Damen Shipyards Mangalia on the Black Sea, in Romania.

With a total cost of $468 million, the vessel is the largest single investment ever made in the marine diamond industry, according to Debmarine. It deploys advanced subsea crawling – a technique for recovering diamonds from the seabed. The new build will be delivered to Debmarine Namibia, a joint venture between the Government of the Republic of Namibia and De Beers Group, in 2022.

Debmarine Namibia extracts some of the highest quality diamonds available anywhere from water of between 90-150 m deep off the south west coast of the country.

The new 177 m ship has been designed by Norway-based naval architects, Marin Teknikk. It will become the largest ship in the owner’s fleet, exceeding the size of Debmarine Namibia’s current largest vessel, the Mafuta, by 8,000 t displacement (vessel weight based on the amount of water displaced by the hull). It is expected to increase the shipowner’s annual production by 35%, contributing an additional 500,000 ct to today’s production levels.

The offshore mining specialist previously installed ABB’s power systems on board the SS Nujoma (SSN), Debmarine Namibia’s deep-water diamond exploration and sampling vessel.

Michael Curtis, who is heading the new build project for Debmarine Namibia, said: “The success of the SSN, with high reliability, efficient positioning and low fuel consumption coupled with safe operation, was instrumental in selecting the same systems for the new diamond recovery vessel, with ABB’s power systems being an integral part of the solution.”

The latest ABB technology will ensure the vessel achieves unsurpassed uptime, according to the company.

In addition to the advanced system for power generation, distribution and variable speed drive propulsion systems, the solution includes a large online double-conversion marine uninterruptible power supply (MUPS) to support the ship’s control processes, significantly reducing the risk of critical power loss and downtime.

“ABB’s MUPS is designed for undisrupted availability, ensuring power backup for the vessel’s on-board control systems of the subsea-crawler and processing plant that sorts through sediment lifted from the seabed to extract diamonds,” ABB said. “ABB’s advanced and tightly integrated power system will help optimise engine loading, as well as reduce running hours and fuel costs, and decrease maintenance needs.”

Juha Koskela, Managing Director, ABB Marine & Ports, said: “This is a truly special ship, packed with sophisticated technology, and a project demanding an especially close relationship with the customer to ensure that optimal solutions were delivered for exact specifications.

“We are thrilled to see that the team behind this advanced vessel recognises the benefits of efficiency, safety and uptime available through integration. This success is also consistent with growing traction for ABB’s electric, digital and connected solutions across an increasing number of vessel types and operational profiles.”

Metso equipment to rough up diamonds at De Beers Venetia mine

Metso is to install high-performance crushing and material handling equipment underground at the De Beers Group’s Venetia diamond mine, in South Africa, as part of an order booked in the September quarter.

In the throes of a transition from open-pit mining to underground operations, Venetia is reported to produce around 4 Mct/y, making it one of South Africa’s biggest diamond mines.

In 2013, an underground extension project commenced with plans to start producing carats in 2022, climbing to full production in 2025 and extending the mine life to 2046.

Metso said Venetia approached Metso to deliver two primary jaw crushers and a number of feeders. All the equipment will be installed underground, which is a very challenging installation, especially given the shaft constraints (dimensions) and weight limitations for transportation underground, the company added.

Venetia decided on Metso’s Nordberg® C Series™ jaw crusher range as the pinned and bolted design of the crusher allowed for the extensive disassembly, Metso said. “This enhances ease of transportation and installation, especially where there are critical space constraints such as an underground installation – as is the case with this project.”

The Metso apron feeders, meanwhile, are used for extracting or feeding ores that are wet, sticky, dry or even frozen.