Tag Archives: Shaft sinking

Murray & Roberts Cementation hits shaft sinking milestone at Palabora

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

The Murray & Roberts Cementation shaft sinking team responsible for delivering a new ventilation shaft at Palabora Copper Mine (PMC) recently celebrated the achievement of a major milestone – reaching the 800 m mark.

This milesttone represents two-thirds of the shaft’s final depth of 1,200 m.

The ventilation shaft forms part of the copper producer’s Lift II project, which 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.

PMC is located within Phalaborwa, in the Limpopo province of South Africa, and the extension of the life of mine will increase shareholders’ value and sustain jobs and livelihoods of the surrounding communities, according to the company. The mine has also initiated several wildlife management programs to minimise the impact of its operations on the environment as well as promote the harmonious co-existence of people, industry and wildlife.

Murray & Roberts Cementation’s contract to sink the 8.5-m diameter shaft was awarded in February 2019. According to Fred Durand, the company’s Senior Project Manager, the shaft sinking is currently making good progress, with 40-or-more lined metres of advance being completed on average each month.

“Shaft sinking operations should be completed by the end of this year with final handover of the shaft to our client, PMC, taking place at the end of the first (March) quarter of 2024,” he says.

Ground conditions have presented a challenge on the project. This has resulted in the shaft lining being taken right down to the blasted face, says Jas Malherbe, Murray & Roberts Cementation’s on-site Project Manager.

“Normally, we would line the shaft to within 12 to 18 m of shaft bottom and support the sidewalls temporarily with split sets and mesh,” he explains. “In practice, this did not prove viable, prompting us to change our approach. The method we’ve adopted is unconventional but has proven to be highly effective.”

Drilling is undertaken by two twin-boom Komatsu 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.

Another key piece of equipment is a Komatsu excavator with a 0.3 cu.m bucket. It is lowered from surface through the stage to shaft bottom and is used for lashing. All the waste rock is loaded into a 11 t kibble, which transports it to surface.

The ground conditions at the shaft are such that blasting tends to produce large rocks that can be difficult to handle.

Malherbe said: “We break these up using the excavator, which has a quick coupler which allows it be fitted with a hydraulic breaker within a few minutes.”

The methods being used at Palabora are based on the Canadian shaft-sinking method Murray & Roberts Cementation has pioneered in South Africa at its Venetia mine contract for De Beers Group.

“We have adapted the method because of the very different conditions we’re facing but many elements remain the same or are very similar,” Malherbe said. “In particular, the high degree of safety offered by the Canadian method has not in any way been compromised.”

The number of Murray & Roberts Cementation personnel deployed per shift is 25. The total labour complement on site is currently just over 120 people, 46% of them recruited from local communities.

Murray & Roberts Cementation has a vigorous CSI program running in conjunction with its contract. It is being implemented in close association with PMC and has mainly focused on supporting local schools in the Phalaborwa area with infrastructure such as ablution facilities, fences, water storage tanks and boreholes.

Durand said: “In addition, we have trained nearly 80 youths from local communities at our Bentley Park Training Academy, near Carletonville. Another 20 are currently undergoing training. This program is giving them skills which are in high demand in mining, and which could lead to them securing permanent employment within the mining industry.”

Anglo American continues SBR-led shaft sinking progress at Woodsmith

Energy minerals, Mine shafts and equipment, Mineral project development, Mining equipment, Mining services, , , , , , , , , , , ,

While Anglo American continues with its detailed technical review of the Woodsmith polyhalite project in the UK, shaft sinking activities at the asset continue to progress, the company confirmed in an investor update today.

The project was acquired by Anglo American in 2020 with the purchase of Sirius Minerals. Since then, Anglo American has been working on refining the development pathway and overall production potential of the asset.

In an investor presentation today, the company outlined physical progress on the site, explaining that shaft sinking for the circa-1.6-km deep service shaft had progressed to the circa-265-m level. It also said the mineral transport shaft, which it is working on with Redpath Group as sinking contractor, had reached the circa-230-m level of a planned 321-m depth.

Regarding horizontal development, it added that the 37-km mineral transport tunnel – which will connect to the mineral transport shaft – had reached the 20-km development mark with tunnel boring machine technology.

The Woodsmith project overview includes the sinking of production and service shafts with 6.75-m diameters – having depths of 1,594 m and 1,565 m, respectively – and the 37-km-long concrete-lined tunnel containing a conveyor belt, which transports the polyhalite ore from Woodsmith mine, near Whitby, to the Mineral Handling Facility, on Teesside, for processing and shipping.

Both the service shaft and production shaft at Woodsmith are being sunk using Herrenknecht’s Shaft Boring Roadheader technology, which has previously featured on the Jansen potash project in Saskatchewan, Canada, where it excavated two 8-11 m diameter blind shafts down to circa-1,000-m-depth and the Slavkaliy-owned Nezhinsky potash project, where it ended up breaking shaft sinking records under the guidance of contractor Redpath Deilmann on a project to sink two 8-m diameter shafts (one to 750-m depth and one to 697-m depth).

The first cut for the service shaft was made in July 2021, with Anglo American and Redpath Deilmann – which is now leading the sinking project as shaft sinking contractor – restarting sinking activities on this shaft earlier this year.

In the same investor presentation issued today, Anglo American said it planned to start sinking in the production shaft in the March quarter of 2023.

While the ongoing review takes place, Anglo American confirmed it had approved $800 million of capital expenditure for Woodsmith next year, focused on shaft sinking and other critical infrastructure as part of its phased approach to the asset.

Stephen Pearce, Finance Director of Anglo American, said on Woodsmith: “As we have said for some time, we are improving the project’s configuration to ensure we realise the full commercial value over the expected multi-decade asset life. This will extend the development schedule and the capital budget, compared to what was anticipated prior to our ownership, and so potentially impact our carrying value of Woodsmith for accounting purposes at the year end.

“Looking ahead, we are even more positive today about the prospects for Woodsmith and its potential to become a high margin, major contributor to our diversified product portfolio given the outstanding nature of the resource and the premium pricing upside we expect to realise for Poly4 – the highly effective, low carbon fertiliser we will produce.”

Alamos’ Island Gold mine keeps giving up its goods

Environmental, Mine operation news, Mine shafts and equipment, Mineral project development, Power supply for mines, Precious metals, , , , , , ,

The latest drill intercepts from Alamos Gold’s Island Gold Mine in Ontario, Canada, have continued to showcase the potential of an asset that already has a more than 17-year mine life ahead of it, John McCluskey, President and Chief Executive Officer, says.

On the same day as releasing an assortment of promising drill intercepts outside of the existing reserves and resources – namely 110.17 g/t Au over 7.79 m, 97.21 g/t Au over 5.05 m and 525.28 g/t Au over 2.33 m – McCluskey continued to highlight the credentials of an asset that had just 1.8 Moz of mineral reserves and resources, and production around the 100,000 oz/y mark when it was acquired by Alamos in 2017 in a $620 million all-share deal for mine owner Richmont Mines.

“We’re now looking at one of the biggest, most profitable underground gold mines in Ontario,” he told IM in a meeting in London this week. “That is a far cry from what the market saw when we first acquired the company. We have since more than tripled the reserve and resource base and continue to build confidence in adding further ounces.”

The Phase 3+ Expansion Study released earlier this year outlined a 2,400 t/d shaft-supported operation with average annual gold production of 287,000 oz, starting in 2026 upon completion of the sinking and equipping of a 1,373-m-deep shaft. This represents a 22% increase from the previous Phase 3 study and a 121% increase from the mid-point of 2022 production guidance of 130,000 oz.

McCluskey confirmed this week that pre-sinking activities at the expansion project had been completed by contractor Redpath, going down to 42 m depth (pictured). He expected full sinking activities to start up next year in line with the above guidance.

The addition of a shaft connected to low-carbon intensity grid power in Ontario will support higher mining rates with a smaller mobile fleet of haul trucks resulting in significantly lower diesel consumption at Island, according to the company. This is expected to drive a 35% reduction in greenhouse gas emissions over the mine life.

While the current plan at Island is to sink down to circa-1,400 m, the company made the decision to acquire a hoisting plant for the expansion that could operate down to depths of 2,000 m. This is an indication of the undefined potential at the mine, according to McCluskey, who admitted the shaft could be sunk to even deeper depths should drilling results justify this.

“It would not require too much more engineering or money to extend the shaft below the circa-1,400 m level, so that is something we will continue to weigh up as we conduct further drilling,” he said. “The Island story continues to grow and we continue to see a very profitable future at what will become one of the lowest cost underground mining operations in the province.”

Orefields Raise Boring, Cementation Canada to collaborate on mining project delivery in Scandinavia

Explosives and blasting, Mine shafts and equipment, Mining services, , , , , , , , , , ,

Sweden-based Orefields Raise Boring AB has established a Memorandum of Understanding (MoU) with Cementation Canada Inc that could see the two companies collaborate on projects in Scandinavia going forward.

Cementation, a global mine development contractor, complements Orefield’s’ mining services, which include pilot drilling, raiseboring, down-reaming, horizontal raiseboring and casting/grouting, it says, offering capability and experience to engineer and sink shafts, drive decline ramps, lateral development, production mining and mine construction to access and mine orebodies.

Additionally, the team’s offerings include full in-house engineering and design-supply services for crushing/screening and conveying systems that condition and deliver run-of-mine ore to the processing facility.

In addition to introducing expanded capabilities beneficial to the broader Scandinavian Region, the Orefields + Cementation Tier 1 Team bring innovative delivery model alternatives that reduce risk for the mine owner when compared with the conventional engineering procuement and construction (EPC) or design-bid-build approaches, they say.

For example, creative risk-reducing alternatives include:

  • Design-build-operate/maintain (DBOM)
    • DBOM + system ownership
    • Following an agreed period of operation, option to transfer ownership
    • Owner’s mine build & mining partner

Cementation explained: “Over the life of the facility, operations and maintenance expenses often far exceed the initial cost to design and build systems. Consequently, the design and construction of the system significantly impacts operational reliability and the resultant costs that accumulate over the years. Our DBOM approach, being performed by a single accountable venture, reduces risk inherent in spreading work packages between different organisations (as with EPC or design-bid-build approaches, for example). Simply put, the principle behind the DBOM delivery model is that we ‘pack our own parachute’, so we make sure it is done right from the beginning through to deployment.”

With this partnership specifically being established in Sweden for the benefit and added value to the Scandinavian Region, technical and professional labour resources, as well as the supply of materials, equipment and fabrication/construction, will be procured in the local regions where possible. Depending on the availability of qualified Scandinavian-based resources, secondary preference will be given to other European Region countries.

Redpath continues mechanised sinking evolution with S20+ deployment at Odyssey

Automation, Explosives and blasting, Mine shafts and equipment, Mining equipment, Mining services, Precious metals, , , , , , , , , , , , , , ,

Redpath is continuing its focus on mechanised shaft sinking operations, with the latest example being the planned use of the hydraulic shaft mucker S20+ at the Canadian Malartic Partnership’s (CMP) Odyssey gold project in Quebec, Canada.

Redpath Canada was recently contracted by the CMP to sink a 6.5-m diameter, 1,800-m deep concrete lined shaft at Odyssey, a project that has the potential to become one of Canada’s largest and most technologically advanced underground gold mines.

CMP, which is 50:50 owned by Yamana Gold Inc and Agnico Eagle Ltd, previously laid out plans to extract 19,000 t of ore at an estimated grade of about 2.75 g/t gold and roughly 5,000 t/d of waste rock during peak operations at Odyssey. The ore will be processed at the operation’s existing plant, which will eventually be adapted to the future mine’s needs including shifting from 57,000 t/d to 20,000 t/d. The ore will be hauled to surface using Blair production hoists with use of both shaft bottom and mid-shaft ore handling systems.

The sinking concept at Odyssey includes the use of the S20+, which was built by Redpath Deilmann in Germany. A previous iteration of this machine, the S20, was used with success on four shaft projects in both soft rock – with an integrated tool package – and hard rock.

The S20+ offers similar capacity/productivity to a North American pneumatic telescopic boom mucker but with a much easier learning curve for operators, according to Kevin Melong, Vice President – Shafts and Technical Services, at Redpath Canada.

Unlike the RD S100, which can move independently of the galloway within the shaft via a telescopic boom, the S20+ is connected to the galloway, requiring the lowering of the galloway to move the mucker into position for mucking.

Melong added: “The S20+ does present some potential for concurrent mucking when in and around the shaft station construction/excavation, but, in general, does not act independent of the stage as in the S100 design.”

Fitted with a bucket as standard, the S20+ offers a maximum digging depth of 7.96 m and a bucket volume of 560 litres. It also offers good flexibility, with the bucket capable of six rotations per minute.

Alongside the S20+ and the aforementioned S100, Redpath has been mechanising the shaft sinking process in mining through the use of large-diameter raiseboring equipment and operation of Herrenknecht’s Shaft Boring Roadheader (in soft-to-medium rock). The company is also working with Herrenknecht on the development of the Shaft Boring Cutterhead, a machine developed for medium-to-hard rock applications up to 250 MPa UCS.

South32 making engineering and design headway at Hermosa project

Automation, Base metals, Energy minerals, Environmental, Mine shafts and equipment, Mineral project development, Mining services, Precious metals, Sustainable mining, Water management, , , , , , , , , , , , , , , , , , , , , , ,

A stellar set of annual financial results has provided the ideal backdrop for South32 to update shareholders on its rapidly progressing Hermosa project in Arizona, USA.

Released late last month, the company’s 2022 financial year results showed off record earnings of $2.6 billion, record free cash flow from operations of $2.6 billion and record return on invested capital of 30.1%.

With group copper-equivalent production expected to increase by 14% in the next financial year, South32 looked to be well leveraged to in-demand metal markets at the right time.

The company has progressively been repositioning its portfolio toward metals critical for a low-carbon future, having already established a pipeline of high-quality development options. One of these high-quality development options is Hermosa.

Hermosa, which the company acquired outright back in 2018 as part of a takeover of Arizona Mining, is key to the company’s critical metals pursuit, having exposure to base and battery metals that are expected to grow in demand – both domestically in the US and internationally.

It is being designed as South32’s first ‘next generation mine’, according to Hermosa President, Pat Risner, with a series of technical reports highlighting its use of automation and technology to minimise its impact on the environment and target a carbon-neutral mining scenario in support of the group’s goal of achieving net zero operational greenhouse gas emissions by 2050.

These same reports also highlighted the potential to develop a sustainable, low-cost operation producing zinc, lead and silver from the Taylor deposit, with the bonus of possible battery-grade manganese output for rapidly growing domestic markets from the Clark deposit.

In the latest results, the company said it was devoting $290 million of growth capital expenditure in the 2023 financial year to progressing Hermosa as it invests in infrastructure to support critical path dewatering and progress study work for the Taylor Deposit. This is ahead of a planned final investment decision expected in mid-2023, which should coincide with the feasibility study.

South32 is devoting $290 million of growth capital expenditure in the 2023 financial year to progress Hermosa

Some $110 million of this was assigned to construction of a second water treatment plant (WTP2) to support orebody dewatering at the asset, alongside dewatering wells, piping systems and dewatering power infrastructure.

An additional $95 million was slated for engineering and initial construction ahead of shaft sinking at the operation, plus work to support power infrastructure and road construction.

The remaining amount was expected to support work across the broader Hermosa project, including Clark study costs and the Taylor feasibility study.

All signs from these results are that the company is laying the groundwork to develop this project ahead of that mid-2023 deadline.

In another sign of progress, South32 recently signed a “limited notice to proceed” for shaft engineering and design at Hermosa with contractor Redpath, Risner confirmed, adding that the award represented a positive step forward for the project.

“We look forward to continuing our engagement with local communities and all of our stakeholders as we make further progress with the project,” he said.

Redpath will no doubt be evaluating the technical studies that have been signed off to this point and informing future reports.

The PFS design for Taylor is a dual shaft mine which prioritises early access to higher grade mineralisation, supporting zinc-equivalent average grades of approximately 12% in the first five years of the mine plan. The proposed mining method, longhole open stoping, is similar to that used at Cannington, in Australia, and maximises productivity and enables a single stage ramp-up to the miner’s preferred development scenario of up to 4.3 Mt/y.

Yet, the Clark deposit opportunity – which has become even more tantalising with the US Government invoking the Defense Production Act and supporting the production of critical metals including manganese – could see the plan change.

The company says it may accelerate the prefeasibility study for the Clark deposit, which is spatially linked to the Taylor deposit. A scoping study has previously confirmed the potential for a separate, integrated underground mining operation producing battery-grade manganese, as well as zinc and silver from the deposit.

South32 previously said Clark has the potential to underpin a second development stage at Hermosa, with future studies to consider the opportunity to integrate its development with Taylor, potentially unlocking further operating and capital efficiencies.

With a PFS selection study expected later this year, investors and interested parties will soon know the role Clark could play in the wider Hermosa project.

What is easy to gauge already is that Hermosa is progressing on a track that many other development projects in in-demand sectors have gone down.

Woodsmith Shaft Boring Roadheaders about to re-start cutting process

Energy minerals, Mine shafts and equipment, Mineral project development, Mining equipment, Mining safety, Mining techniques, , , , , , , , , , , , , , , , , , , ,

One of the most-watched shaft sinking projects in the sector right now is located in the UK, with the Woodsmith project in north Yorkshire having been on the radar for a number of reasons.

First off, it is a project that has changed hands recently.

Originally guided by Sirius Minerals, the 10 Mt/y project was acquired by Anglo American in 2020, a transaction that came with a fresh look at the whole project execution phase.

The change in ownership and re-assessment of plans drawn up by Sirius – a much smaller company guided by different investor pressures and operating procedures – led to Anglo American relieving DMC Mining, the lead shaft sinking contractor, of its duties.

Another reason for watching the project is the planned use of Shaft Boring Roadheader (SBR) technology from Herrenknecht.

After debuting at the Jansen potash project in Saskatchewan, Canada, where it excavated two 8-11 m diameter blind shafts down to circa-1,000-m-depth with the help of DMC as the contractor, SBR 2.0 – the second generation of the technology – was put to the test in Belarus at the Slavkaliy-owned Nezhinsky potash project. It ended up breaking shaft sinking records under the guidance of contractor Redpath Deilmann on a project to sink two 8-m diameter shafts (one to 750-m depth and one to 697-m depth).

Herrenknecht, with its experience in mechanised tunnelling, developed the SBR for the mechanised sinking of blind shafts in soft-to-medium rock. Based on the proven technology of the Herrenknecht Vertical Shaft Sinking Machine, the SBR offers improved safety performance compared with conventional shaft sinking methods while also achieving higher advance rates, according to the company.

The SBR is a 60-m tall, suspended shaft sinking machine, with 12 work decks and two service platforms. A telescopic, boom-mounted cutting head is used to precisely excavate rock via a partial-face cutting method. The cutting head works in a cycle, starting each cut from shaft centre to shaft wall, repeating until a layer of material is removed. Excavation proceeds in 1-m increments, followed by SBR lowering sequences.

The SBR was chosen for Woodsmith by Sirius over the conventional drill and blasting method due to its advantages in improving safety and schedule. This methodology, Sirius said, would allow the company to satisfy several operational objectives, moving away from the use of explosives and providing a safer, more predictable work method. Instead of a linear process, the SBR allows work to be completed concurrently as the shaft is sunk, as well as minimising damage to exposed host rock, and further improving safety while minimising downtime. Work decks above the cutting head allow workers to install shaft lining and tubbing as excavation continues, while a pneumatic mucking system removes waste rock.

The third generation of technology – which builds on the first two deployments with, among other things, the addition of two retractable robotic probes to test and grout the ground ahead for safer excavation and an additional control cabin on surface for more remote operation – is due to sink production and service shafts with 6.75-m diameters to depths of 1,594 m and 1,565 m, respectively, at Woodsmith based on the Sirius plan.

These SBRs are being supported by four triple sheaved winches from SMS SIEMAG and conveyors from Herrenknecht-owned H + E Logistik GmbH, among other support equipment.

Work on the service shaft commenced in 2021 with former Anglo American Chief Executive, Mark Cutifani, confirming in July of that year that the “first cut” with the SBR had taken place in the service shaft.

This progress was made while the company was still completing a detailed technical review on Woodsmith to ensure the technical and commercial integrity of the full scope of its design. This review has a particular focus on the sinking of the two main shafts, the development of the underground mining area, and the changes required to accommodate both increased production capacity and the more efficient and scalable mining method of using only continuous miners, Anglo American said.

Since the first cut was made in July 2021, however, Anglo American and Redpath Deilmann – which is now leading the sinking project as shaft sinking contractor – have been reviewing the existing plans for sinking with the SBRs, carrying out minor hardware changes on the machines and ensuring all staff have the appropriate training to facilitate the completion of the shaft sinking process. The Redpath Group is also involved in the drill-and-blast-based sinking for the materials transport system (MTS) shaft.

Various shaft sinking rates have been mooted in the past at Woodsmith, and Anglo American is currently working to develop the optimal solution for the facility based on technical standards.

The sinking at Woodsmith represents a different challenge to the two previous SBR projects conducted to this point.

For starters, there is no ground freezing expected to take place at Woodsmith – unlike what happened in Canada and Belarus. This process, while time consuming and only used to freeze unstable water-bearing strata around the shaft, can create more rock uniformity to aide consistent cutting rates.

There is also the MTS level to consider at Woodsmith, with plans to carry out lateral development work around the 360-m-level to join up the production shaft with this level where polyhalite ore will be transported along a 37-km tunnel to Wilton near the port. This means vertical cutting and loading may be halted while the MTS level connection is established.

All these factors, along with the performance of previous SBR work, will be incorporated into the engineering work Anglo American is carrying out at Woodsmith, but, in terms of the SBR, signs are that work on the service shaft could recommence shortly, with plans to start sinking in the production shaft by the end of the year.

Cementation, Sandvik and Micon achieve flexible raisebore-based sinking at Solvay Chemicals #5 shaft

Energy minerals, Explosives and blasting, Mine shafts and equipment, Mineral project development, Mining industry recognition, Mining safety, Mining services, , , , , , ,

Cementation Americas has announced the completion of the full faced raisebored raise at Solvay Chemicals #5 shaft in Green River, Wyoming, USA.

The project required the company to complete a 22 ft (6.7 m) diameter shaft, complete with concrete liner, from surface to a depth of 1,506 ft (459 m).

Concrete liner thickness increased as the depth of the shaft increased, so the initial concept was to complete a pilot slash raise with a raisebore drill and then slash from the top down to achieve the differing diameters to accommodate concrete liner thickness, the company explained. Cementation instead proposed a full face raisebored shaft solution with variable diameters for each section.

“We worked closely with Sandvik to design, engineer and manufacture a reaming head that could be diminished in diameter rather than manufacturing different diameters of outside wings,” Cementation said. “Final design allowed for five diameter options; maximum of 26.67 ft (8.1 m), down to 24.48 ft, in increments of 6.6 in (168 mm). The 26.67 ft. diameter reamer consisted of 12 individual sections, 46 cutters and weighed 136,000 lbs (61,689 kg).”

Following completion of 68 ft deep collar excavation and lining, Cementation’s Strata 950 Raise Drill was set up over the collar and a 16 in diameter pilot hole was drilled with Micon’s rotary vertical drilling system (RVDS). When the completed pilot hole was surveyed, the total deviation from vertical was found to be less than 4 in over entire length of pilot hole, according to the company.

Based on the pilot hole survey, it was determined that the first leg of the shaft would be reamed to 26.13-ft diameter for 588 ft of shaft, followed by 25.02-ft diameter for the next 285 ft of shaft and 24.47-ft diameter for the final 535 ft of shaft to surface.

Reaming of the shaft was completed on April 24 and the Cementation shaft crews are now in the process of completing the shaft lining.

This raise was one of the largest ever pulled in the Americas and was completed without incident, the company noted.

Its success was the result of a collaborative effort by all parties involved by providing the best technical solution for the Solvay Chemicals #5 Shaft, which is part of the company’s trona operations in Green River.

Pictured is the Solvay reaming head at the Sandvik workshop in Sudbury, Ontario, Canada

Master Drilling talks up MTB 2.0 as it progresses work on Shaft Boring System

Automation, Explosives and blasting, Mine operation news, Mining equipment, Mining services, Precious metals, Sustainable mining, , , , , , , , , , ,

Master Drilling Group’s annual results presentation provided a few eye-opening updates on the company’s mechanised mine development fronts, with Director, Koos Jordaan, highlighting a potential first deployment of the company’s Shaft Boring System (SBS) at Royal Bafokeng Platinum’s Styldrift mine in South Africa.

A raiseboring specialist that has diversified into other complementary areas over the last decade, Master Drilling has consistently devoted capital towards its technology developments.

During the 2021 annual results presentation, Jordaan confirmed that the company had started tunnelling work on an exploration decline at Anglo American Platinum’s Mogalakwena PGM mine in South Africa, using its Mobile Tunnel Borer (MTB), as well as highlighted the ongoing development of a next-generation design that would cater to the industry need to safely and quickly establish twin declines for mine access.

The MTB is a modular horizontal cutting machine equipped with full-face cutter head with disc cutters adapted from traditional tunnel boring machines. Unlike these traditional machines, it is designed to work both on inclines and declines, with the ability to navigate around corners and construct 5.5-m diameter decline access tunnels.

Having initially been tested in a quarry in Italy in soft rock, it then made the trip back to South Africa to carry out a 1.4 km project at Northam Platinum’s Eland platinum group metals operation in South Africa, in harder rock. This project was terminated in March 2020 due to the COVID-19 pandemic. Last year, however, the company announced it had signed an agreement with Anglo American Platinum to deploy the MTB at Mogalakwena as part of a turnkey contract to sink an exploration decline.

On the development of MTB 2.0, Jordaan said: “We are already working on the second-gen MTB being confident that the concept provides competitive value versus the past as well as other current developments.”

He said the company envisioned future projects using two MTBs simultaneously to establish traditional twin declines for access to underground mines for fast access from “A-to-B” and a quick turnaround to steady-state mining operations.

The company is also carrying out early-stage work with Element Six and the De Beers Group on cut and break technology which, when applied in tandem with the use of the MTB, could enable even more continuous cutting applications.

Element Six, as a company, was established to harness the unique properties of synthetic diamond (polycrystalline diamond or PCD) and tungsten carbide to deliver supermaterials that improve the efficiency, performance and reliability of industrial tools and technology. One of the obvious applications was in hard-rock cutting where OEMs have trialled PCD materials.

Jordaan said the company could leverage cut and break technology with MTBs to create flat floors and breakaways, allowing the circular MTB to continue cutting the face without stoppages.

Looking at vertical developments, Jordaan also provided an update on the SBS.

This machine was initially billed as a blind shaft boring system able to sink 4.5-m diameter shafts in hard-rock down to 1,500 m depth.

Last year, Jordaan said it planned on introducing a “smaller scope system” as part of its introduction to the industry, adding that it had signed a letter of intent with a prospective South Africa project that could see a machine start sinking activities in the first half of 2022.

In the most recent update, he said the letter of intent was with Royal Bafokeng Platinum’s Styldrift mine.

“We are now building the SBS and working towards hopefully converting the letter of intent from RB Platinum to a contract award; we already engaged with them in investigation and readiness work should approval be granted,” he said.

The first SBS being built is a 4.1-m-diameter scope machine with a capability of sinking shafts up to 1,500 m depth, according to Jordaan, who explained that this “smaller shaft scope” was part of a plan to lower the machine’s implementation cost.

“But we are already engaged with opportunities regarding a larger scope of service,” he clarified. “The cost benefit of this method drastically increases as the scope increases versus conventional sinking.”

Aside from the MTB and SBS projects, Jordaan said the company was working on the LP100 development project for its raiseboring division. This is a highly mobile and high-capacity articulated wheel carrier to carry out up and down slots, as well as smaller raiseboring holes, remotely, he explained. At the same time as this the company is looking at developing electric track carriers for its raisebores that, when applied, would come with a much lower carbon footprint.

This came on top of plans for a new box hole boring machine, two new core drilling rigs – one for underground and one for surface – and an experimental rock cutter machine it is working on with African Rainbow Minerals in South Africa.

Anglo American signals design changes at Woodsmith polyhalite project

Energy minerals, Explosives and blasting, Mineral project development, Mining services, , , , , , , , , , , , ,

Anglo American has outlined plans to change elements of the design at its Woodsmith polyhalite project in the UK, which will have a bearing on both the sinking of the two main shafts and development of the underground mining area at the project.

The company has been running a detailed technical review on Woodsmith since mid-2020 to ensure the technical and commercial integrity of the full scope of its design. This followed the acquisition of the asset as part of a takeover of Sirius Minerals earlier that year.

“Now largely complete, the review has confirmed the findings of Anglo American’s due diligence that a number of elements of the project’s design would benefit from modification to bring it up to Anglo American’s safety and operating integrity standards and to optimise the value of the asset for the long term,” the company said.

Anglo is also making a change to the leadership at Woodsmith following its integration into Anglo American and ahead of the full project execution phase. Tom McCulley, who has led the development of the Quellaveco copper project in Peru, will take over from Chris Fraser as CEO of Crop Nutrients. This will see Fraser step aside and take on a strategic projects role for Anglo.

“The Woodsmith team is further developing the engineering to optimise the configuration of the project, recognising the multi-decade life of the mine,” Anglo said.

Particular attention is on the aspects identified at the outset of Anglo American’s ownership – namely, the sinking of the two main shafts, the development of the underground mining area, and the changes required to accommodate both increased production capacity and the more efficient and scalable mining method of using only continuous miners, it said.

The sinking of the two main shafts is due to be carried out using Herrenknecht’s Shaft Boring Roadheader (SBR) technology. DMC Mining, a company familiar with the technology thanks to its work sinking shafts at Jansen in Saskatchewan, Canada, was previously tasked with sinking the production and service shaft, each around 1,500 m deep, and two smaller shafts associated with the materials transport system, each approximately 350 m deep. Its contract was ended in 2020.

These improvements will, the company said, require the installation of additional ventilation earlier in the development of the underground mining area.

“Anglo American expects that these changes to the design of the mine infrastructure – which will result in a different, enhanced configuration and therefore a different construction and production ramp-up schedule – will ensure that its exacting standards are met and the full commercial value of the asset is realised,” the company said.

Mark Cutifani, Chief Executive of Anglo American, said: “We are very happy with the high quality and exciting potential of Woodsmith, with the scale and quality of the polyhalite orebody pointing to a quartile one operating cost position and strong margins. This is a very long-life asset and we are going to take the necessary time to get every aspect of the design right to match our long-term vision and value aspirations.

“We have said from the outset that we expect to make improvements and that we will execute certain elements of the construction differently and with a more conservative schedule. We expect to have completed our design engineering, capital budget and schedule at the end of 2022, with a fully optimised value case that recognises the upside potential we see in Woodsmith, and we will then submit the full project to the board.”

In the meantime, construction of the major critical path elements of the project, principally the two main shafts and the mineral transport tunnel, is progressing, with approximately $700 million of capital expected to be invested in 2022, Anglo said.

The plan at Woodsmith under previous owners Sirius was to extract polyhalite via two mine shafts and transport this outside of the National Park to Teesside on a conveyer belt system in an underground tunnel. It would then be granulated at a materials handling facility, with the majority being exported to overseas markets. The company was previously aiming to achieve first product from the mine by the end of 2021, ramping up to an initial production capacity of 10 Mt/y and then full production of 20 Mt/y.

The changes to McCulley’s and Fraser’s roles are effective January 1, 2022. Anglo American has appointed Adolfo Heeren as CEO of Anglo American in Peru, effective from the same date. Heeren will work together with McCulley during the first half of 2022 to ensure a smooth transition from the construction and commissioning phase of Quellaveco into operations, expecting first copper production in mid-2022.