Tag Archives: Ghana

Sandvik helping facilitate Rocksure’s mining services growth in Ghana

Rapidly growing mining services provider Rocksure International in Ghana, Africa, has had a 100% Sandvik drill rig fleet since it was established and, according to the OEM, the partnership has been delivering spectacular results.

With drill rigs used in mining applications, the secret to success is to keep them in tip top condition throughout their working lives.

So, parts – who makes them and the service that comes with them – is of critical importance for these machines, Sandvik says.

By adopting the best work practices and latest premium equipment, Rocksure has gone from two drill rigs and eight employees when it was established in 2009, to today’s fleet of over 20 rigs and 1,200 workers. In the process, the company has been winning work that was once the preserve of Western multinationals.

In 2020 Rocksure delivered some 50 Mt of material to its customers in Ghana’s gold fields and is soon to be working on a major bauxite project in the West African country.

Partnership is the new leadership

Part of Rocksure’s strategy is to partner with leading equipment brands – and its fleet now includes 123 pieces of heavy equipment, all from the biggest names in the mining industry.

All of its drill rigs are from Sandvik, all of which have been supplied with comprehensive parts, service and training support bundles, the OEM says.

The predominant machine used by Rocksure is the Sandvik Pantera DP1500i. It is a hydraulic top hammer drill rig designed for production or pre-split drilling in open-pit mines, drilling holes with a diameter of 89-152 mm. The company also has a Sandvik DE881 multipurpose exploration rig.

“We work closely with clients like Rocksure to understand their needs,” Daniel Korsah, Sandvik Business Line Manager for Surface Drilling in West Africa, says. “We look at a long list of site variables, including blast efficiency, hole depth, length, type of rock, etc – and that helps inform the type of equipment we recommend. But that is only half of the story – the aftermarket support package is also vital to customer success.”

Fellow Business Line Manager Parts & Services, Ricus Terblanche, added: “It’s our job to make sure the rigs maintain their productivity targets, reduce costs and help the customer be more profitable. To ensure this, we look at the site data and use it to build a comprehensive parts list of the supplies that are likely to be needed. These parts are then ordered in conjunction with the machine sale, and both delivered to site at the same time. For major projects we can put large parts stocks in place, from which Rocksure can draw using a vendor-managed inventory approach. But our support bundles are much more than parts and include machine operation and safety training.

“We would never sell a machine unless we were sure the customer could operate it effectively and safely and had the skills and resources to support it.”

A recent sale of Sandvik Pantera DP1500i machines saw Sandvik support Rocksure with a four-week intensive classroom and practical operator and technical (maintenance) training, along with three months of asset support. This involved technicians being on site 100% of the full time, providing on-the-job coaching and inspections to ensure the rigs are operating to their highest potential, Sandvik explained.

Predictive parts replacement

Using Smart Inspections supported by years of accumulated analysis on component lifespan, Sandvik can calculate predictive operating costs and recommend a parts replacement service policy before parts fail.

Typically, when the machine has reached 14,000 hours of operation, the Sandvik Pantera DP1500i’s operated by Rocksure undergo a comprehensive overhaul, which can include the installation of new engines, pumps, track frames and undercarriage parts. Adding new technology can bring the machines to a better-than-new condition, with a significant reduction in fuel consumption, according to Sandvik. The fitting of new monitoring systems also helps to give much greater visibility of drilling performance – data that can further help boost productivity.

Terblanche said: “Rocksure is the perfect customer. They are professional, experts in their local market and loyal towards Sandvik – as well as growing at a fantastic rate. We do our best to support them with all the tools at our disposal to maximise their production performance. It’s a great partnership – when Rocksure is successful, Sandvik is too.

“A local mining services supplier supported by a global equipment manufacturer is a winning combination.”

Murray & Roberts’ da Costa heralds positive impact of TNT, Insig on mining platform

The global mining platform of Murray & Roberts has significantly extended its capabilities over the past several years with two key acquisitions in the US and Australia, Mike da Costa, CEO of the platform, says.

The two companies in which majority interests have been acquired are San Diego, USA-based Terra Nova Technologies, a materials handling specialist, and Australia-based start-up Insig Technologies, which develops and provides digital solutions in the mining field.

Terra Nova designs, supplies and commissions overland conveyors, crushing/conveying systems, mobile stacking systems and in-pit crushing and conveying systems. It has delivered around 75 projects in more than 15 countries, according to Murray & Roberts.

“Terra Nova is a perfect fit for M&R’s mining platform and gives us the capability of delivering, for example, conveying systems of up to 12 000 t/h capacity,” da Costa says. “Its biggest market is North America but it is also active in South America and has an office in Santiago, in Chile. It has, in fact, just won a major contract in Chile.

Our intention is to grow the business by leveraging our global footprint. We will soon establish an Australian arm and we could also bring the company’s services to the African market.”

Commenting on the Insig Technologies acquisition, da Costa says the company is playing a key role in the mining platform’s move towards greater digitalisation of its operations.

“We’ve been working on a digital strategy for the mining platform for some time now and the acquisition of Insig is central to our digital journey,” he says. “Insig’s speciality is extracting data from underground mining environments in real time and then using this data to optimise operations. The company also has in-depth capability in the remote control of machines. We will be using its systems in house initially but will eventually market them to the wider mining industry.”

Interestingly, Insig is playing a key role in developing an energy-saving solution at an Australian mine where our Australian company is working. “Basically, we’re looking at capturing the energy that would normally be wasted in a hoisting shaft and storing it in batteries,” da Costa explains.

Insig Chief Technology Officer, Giacomo Alampi; Toran Filippi – Manager Operations Technology; Peter Ellery, Growth Executive; and Brett Hartmann – Manager Digital & Technology at Murray & Roberts, went into detail about this project in a discussion with IM earlier this year.

The Murray & Roberts mining platform consists of three regional businesses. These are Murray & Roberts Cementation, headquartered in Johannesburg but with branches in Kitwe in Zambia and Accra in Ghana; Cementation Americas (which incorporates Cementation USA), based in Salt Lake City, which handles the Americas; and RUC Cementation, which operates out of Perth in Australia and works throughout Australasia and South-east Asia.

Knelson concentrator, Gekko ILR set to boost gravity gold recovery at Asante’s Bibiani

Asante Gold’s plan to bring the Bibiani mine in Ghana into production in the September quarter of 2022 remain on track after mobilising a contractor to refurbish the process plant and made plans to upgrade its gravity gold recovery equipment.

The company acquired the mine earlier this year from Resolute Mining, embarking on a journey to return the former operating mine to its past glories.

In a market update, Asante said all activities for the restart were on track.

“Asante is preparing a plan to deliver a mine that can produce approximately 190,000 oz of gold at Bibiani in its first 12 months of operation and circa 240,000 oz every year thereafter for a minimum of six years,” it said.

Tenders have been invited for the selection of a mining contractor, with mobilisation of said contractor expected to proceed in the March quarter of 2022.

At the same time, the process plant refurbishment is slightly ahead of schedule and on budget, the company said.

Harlequin International has been contracted to complete the refurbishment engineering procurement and construction management (EPCM) and has mobilised as scheduled. The full EPCM team, plus requisite complement of tradespeople, is on site to provide training, safety and project delivery systems and resources needed to ensure achievement of a safe and productive work environment, the company said.

Asante explained: “All work activities are proceeding as planned. Principal equipment motors and drives have been taken off site, to be serviced as needed. Electrical components, instrumentation and control systems have been tested and are being upgraded as needed to provide improved performance, above the original design.”

The company said gravity recovery equipment was being upgraded to “2020 level” of competence and automation. This includes the purchase of a new high efficiency “6G Knelson concentrator” (from FLSmidth) and Gekko ILR (InLine Leach Reactor).

Sub-contractors have been engaged to proceed with sand blasting, metal and pipework repair, painting, installation of liners and belts, and to ensure safe and efficient operation, Asante said.

“Equipment that is on site but that was not fully installed by the former owners is in the process of being made ready for operation,” the company added. “As of the last week of October, there are more than 200 workers on site. To date the project remains on budget.”

In July 2018, Resolute Mining, based on some 50,500 m of drilling, released an updated feasibility study for Bibiani reporting JORC compliant resources of 21.7 Mt at 3.6 g/t for 2.5 Moz of gold.

AMS to continue servicing AngloGold’s Iduapriem with help of MAXMASS

AMAX, a joint venture between Perenti Global’s surface mining business in Africa, African Mining Services (AMS), and Ghana-based mining services company MAXMASS Ltd, has been awarded a new circa-A$470 million ($346 million), five-year contract at AngloGold Ashanti’s Iduapriem gold mine in the Western Region of Ghana.

Perenti’s work in hand will increase by circa-A$280 million over the term of the contract, which is expected to commence immediately.

The new contract is structured as a 60:40 joint venture agreement between AMS and MAXMASS and represents AMS’ significant and ongoing commitment to developing and expanding the capacity and capability of local partners, Perenti explained.

Mark Norwell, Managing Director and CEO of Perenti, said the continued transformation of AMS, including the winning of quality projects underpinned by robust financial and commercial disciplines, remains a key strategic initiative in Perenti’s 2025 Group Strategy.

“We’re delighted to be extending our relationship with our long-standing client, AngloGold Ashanti,” Norwell said. “AMS has a reputation for delivering excellence while generating enduring value and certainty for stakeholders and the award of this new contract at a site where AMS has previously operated for AngloGold Ashanti provides further support for that reputation.”

Perenti Mining Chief Executive Officer, Paul Muller, said AMS had a long history of delivering operational excellence and value to clients, having provided mining services in Ghana for 30 years.

“We have provided surface mining services at the Iduapriem gold mine since 2012, establishing a successful partnership with AngloGold Ashanti,” he said. “We look forward to continuing to strengthen this partnership and also welcome the opportunity to work with our newest joint venture partner, MAXMASS.

“We have a strong commitment to support and build local capability to generate social and economic value for the regions in which we operate. Under this contract, and through the AMAX joint venture, we expect to continue to support the many local businesses that have become important suppliers and contractors to our operations under previous contracts. The joint venture also expects to employ more than 475 Ghanaians with approximately 40% of the workforce employed from the surrounding local communities and the remaining 60% from other regions within Ghana.”

Iduapriem is an open-pit mine with two circuits each comprising two-stage milling – a gravity circuit and a carbon-in-leach (CIL) plant. The gravity circuit recovers about 30% of the gold and the remainder is recovered by the 418,000 t/mth capacity CIL plant, according to AngloGold.

Newmont to add to Ghana gold production with Ahafo North development

Newmont Corp’s Board of Directors has approved advancing the Ahafo North project, in Ghana, into the execution phase, setting the company up to develop four open-pit mines and a standalone 3.7 Mt/y plant.

The project exceeds the company’s required internal rate of return, adding profitable production from the best unmined gold deposit in West Africa, it said.

Newmont President and CEO, Tom Palmer, said: “I am pleased to announce the approval of full funding for the Ahafo North project, expanding our existing footprint in Ghana and adding more than 3 Moz of gold production over an initial 13-year mine life. The development of this prolific orebody will leverage our proven operating model and will be supported by our existing world-class Ahafo South operation.

“The project will be developed and operated in a sustainable and responsible manner to create value for all our stakeholders.”

Located some 30 km north of Newmont’s existing Ahafo South operations (pictured) – which are expected to produce 515,000 oz of gold this year – Ahafo North’s production is expected to average approximately 275,000-325,000 oz/y with all-in sustaining costs of $600-$700/oz for the first five years. Projected capital costs are estimated to be between $750-$850 million with construction expected to be complete in the second half of 2023. At current gold prices, the project is expected to deliver more than a 30% internal rate of return, Newmont said.

The project will create approximately 1,800 jobs at the peak of construction with more than 550 permanent roles created once the mine is operational.

“Newmont will work to create lasting value for host communities through local sourcing and hiring,” the company said, adding that a key aspect of the Ahafo North project’s workforce planning will be a target to achieve gender parity in the workforce when operations begin.

The full scope of funding will be deployed to high-impact activities, including but not limited to finalising engineering and EPCM services, relocating the national highway and support of additional resettlement activities, mining development for four open pits, constructing and commissioning a 3.7 Mt/y plant, constructing a tailings and wastewater management storage facility, long-lead sourcing including the acquisition of 14 Caterpillar 770 haul trucks.

Automation, electrification, alternative haulage weighed for GSR’s Wassa UG expansion

A preliminary economic assessment (PEA) on the potential expansion of Golden Star Resources’ Wassa gold mine in Ghana has flagged the potential for applying alternative underground haulage methods, and autonomous and battery-electric equipment at the operation.

The PEA provides an assessment of the development of the Southern Extension of Wassa and the increase in mining rates to fully use available process plant capacity. While the study itself represents a conservative plan that excludes exploration opportunities from the scope and adopts the current mining practices and equipment, the “opportunities” section of the technical report outlines some more innovative approaches to expanding mining rates and filling the plant capacity.

Wassa, which Golden Star owns 90% of, produced 168,000 oz of gold in 2020 using the sub-level longhole open stoping method.

The PEA is focused on the development of the large inferred mineral resource (just over 7 Moz) which comprises the Southern Extension zone. Around 50% of the total resource was included in the PEA inventory, which showed off a life of mine of 11 years, with total gold production of 3.5 Moz. Average annual gold production of 294,000 oz represented an approximate 75% increase on the current production rate.

The mine plan considers a production rate targeting the processing capacity, at or close to 2.7 Mt/y run-of-mine material, after a five-year ramp-up period. The plant has previously operated at these rates with feed from both Wassa and the Bogoso-Prestea operation (since sold).

Mining would be by underground trackless decline access (1:7 gradient), with access from duplicate access ramps and independent ventilation infrastructure on each side of the deposit to support the increased mining rate and provide efficient access across the mineralised footprint (circa-850 m along circa-300 m across strike). Truck haulage will utilise the dual access ramps.

The mining method proposed for the expansion is bottom-up long hole open stoping with 25 m level spacing and nominal stope sizes of 25 m length x 30 m width x 25-100 m height with cemented paste backfill. Stopes will be mined in a primary-secondary sequence down to around 1,000 m depth, transitioning to pillarless retreat below that point to account for increasing in-situ stress, which will need to be further investigated in future work.

The PEA assumes average recovery of 94.8%, which is supported by current plant performance and metallurgical test work on a small number of samples that suggest processing performance for the Southern Extension feed will be similar to material currently treated. This will be evaluated in the next phase of work.

Capital expenditure is expected to total around $790 million over the life of the PEA mine plan. Of this total, 29% is growth capital and 71% is sustaining capital. The PEA mining method relies on paste fill, with Golden Star confirming the paste fill plant was constructed in 2020 and commissioning is expected to be finalised this quarter. Capital has been allowed for an expansion of the paste fill system in the PEA mine plan.

Based on a $1,300/oz gold price, the expansion project is expected to generate a post-tax net present value (5% discount) of $452.2 million.

So far, so conventional…

The company said it planned to complete option and trade-off studies to optimise the project plan ahead of a feasibility study on the expansion, due in early 2023.

Just some of the innovations being considered in these trade-off studies include the use of automation, electrification and alternative haulage.

In terms of increasing machine productivity through technology, the study listed off the potential use of semi- or fully-autonomous vehicles to increase shift operating time and remove operators from hazardous areas. It said the highest likelihood applications were in production drilling and drawpoint loading.

Golden Star confirmed current projects included in its in-development technology roadmap were the introduction of tele-remote loading and digitalisation of production data.

In terms of haulage infrastructure opportunities, Golden Star said it was considering the replacement of truck haulage with an infrastructure system like shaft hoisting, conveyor, or Rail-Veyor. The capital demand for such options would be offset by a large reduction in operating costs with automated systems, reduced diesel consumption and reduced ventilation demand, it noted.

These haulage options were being studied to design different systems, estimate capital and operating costs, then complete a trade-off analysis, the company said.

The current mine design assumes loaders digging from open passes to load trucks, but Golden Star said feeder systems could be installed to automate loading, increasing efficiency and reducing operating costs.

And, of course, the company said it was considering options for clean energy technology applications, particularly battery-electric trucks. As part of this, it was assessing available systems and developing fleet selection criteria. This will have knock-on benefits to the mine’s ventilation requirements.

Gold Fields installs CAS safety solution at Tarkwa gold mine

Gold Fields is upping the safety stakes at its Tarkwa gold mine in Ghana, employing a collision avoidance system (CAS) that should reduce the number of vehicle-to-vehicle and vehicle-to-personnel interactions at the open-pit operation.

Having installed a fatigue management system back in 2012-2013 – which saw equipment interactions and accidents decrease – the company has now purchased the HxGN MineProtect Collision Avoidance System Pro as part of a “discrete, dedicated project”, a company spokesperson confirmed to IM.

Hexagon says the CAS Pro system protects all mining vehicles, assets and vehicle operators within 500 m of the installed cab-based unit in open-pit mines.

The solution provides 360° awareness for surrounding vehicles and selected assets, as well as a collision avoidance function based on path prediction, the company explained.

Using GNSS and RF technologies, the solution enjoys high operator adoption because of minimal nuisance alarms and enhanced safety for all mine and vehicle types, according to Hexagon.

The Gold Fields spokesperson said CAS Pro was being used in line with Earth Moving Equipment Safety Roundtable (EMESRT) guidelines. The solution includes operator awareness and advisory controls, the spokesperson added.

As part of the project, Gold Fields has issued 150 personal tags to employees working near operating equipment, including spotters and samplers. The operating equipment to benefit from the new solution includes 84 dump trucks, 21 excavators, 65 pieces of ancillary fleet (including loaders, dozers and service trucks) and 100 light vehicles (50 with fixed CAS units and 50 with removable units).

While the CAS solution does not include anti-braking functionality, it does have a range of other intervention procedures, according to the spokesperson.

“Stopping a plus-200 t haul truck in milliseconds in an open-pit environment may create other hazards,” the spokesperson explained.

Gold Fields to trial Caterpillar dual-fuel solution on haul trucks at Tarkwa mine

Gold Fields plans to test the use of LNG to power haul trucks in a trial at its Tarkwa open-pit gold mine in Ghana, CEO Nick Holland told attendees of the IMARC Online event this week.

Speaking on a panel reviewing progress of the Innovation for Cleaner, Safer Vehicles (ICSV) initiative – a supply chain collaboration between the International Council on Mining and Metals (ICMM) and original equipment manufacturers (OEMs) – Holland said the trial would involve a mix of LNG and diesel fuel at the operation, and four trucks would initially be tested with the fuel combination in 2021.

Gold Fields later confirmed to IM that the trial would take place in the second half of 2021 and involve the use of Caterpillar’s dual-fuel LNG Dynamic Gas Blending (DGB) retrofit system on four of the mine’s Cat 785C 146 t payload dump trucks.

The DGB conversion kits, available on Cat 785C and 793D haul trucks, are a dual-fuel technology that enables miners to substitute diesel fuel with LNG, according to Cat. The use of LNG has been proven to reduce emissions by up to 30%, as well as lower costs by up to 30%, Cat says.

DGB vaporises liquid fuel into natural gas, then replaces diesel fuel with LNG when possible. On average, DGB replaces about 60-65% of diesel with LNG, according to Cat.

Tarkwa, which is 90% owned by Gold Fields, produced 519,000 oz of gold in 2019, 1% lower than the 525,000 oz produced in 2018. It employs Engineers & Planners Co Ltd as mining contractor.

While this trial will potentially lower the company’s carbon emissions – as will Gold Fields’ plan to fit “diesel filters” on all its machines underground in the next 12-18 months – Holland pointed to a much loftier long-term goal during the ICSV panel.

“The challenge to our teams and OEMs is to move away from diesel completely,” he said.

Such a move could see the company employ both battery-powered and hydrogen-powered solutions at its underground mines, he added.

Obuasi gold mine becomes ‘modern, mechanised mining operation’

The renowned Obuasi gold mine, in Ghana, is back in action with AngloGold Ashanti confirming the redeveloped asset has poured first gold, five years since mining activities were suspended.

This achievement signals the successful redevelopment of the mine into a “modern, mechanised mining operation”, the company said.

The Obuasi Redevelopment project, which seeks to access Obuasi’s 30 Moz orebody over the next two decades and beyond, has completed the first phase of construction on time and on budget. Refurbishment of an existing plant and construction of new infrastructure and underground development, in line with a new mine plan, has taken place over the last 18 months.

AngloGold Ashanti Chief Executive Officer, Kelvin Dushnisky, said producing first gold on budget and on a tight schedule was a “significant achievement” for the company, the community of Obuasi and Ghana as a whole.

“Restarting this important mine is testament to the focused execution by our team on the ground, as well as the clear investment framework and supportive environment created by the President of Ghana and his government, and the King of Ashanti,” he said.

Following a ramp-up period, AngloGold Ashanti estimates mining at a rate of 2,000 t/d from Obuasi during 2020, climbing to 4,000 t/d by year-end. The mine will be producing gold at an average run-rate of 350,000-400,000 oz/y for the first 10 years, and above 400,000 oz over the life of mine at all-in sustaining costs of around $800/oz, according to the company.

Graham Ehm, AngloGold Ashanti’s Executive Vice President of Group Planning and Technical, who is overseeing the project, said: “The team has done an excellent job completing the first phase of this project and will be focused on ramping up production through next year.

“The difficult decision was made to suspend production in 2014 to rebuild the mine’s foundation for a sustainable long-term future that will bring benefit to the region over the coming decades. We are tremendously proud of what has been achieved since then.”

The underground mine development is ongoing, with deepening of the Obuasi Deeps Decline and access to the KRS shaft on schedule for mid-2020. The construction of new plant and infrastructure will continue in 2020. The initial project capital for Obuasi remains in the range of $495-$545 million, spent between 2018 to the end of 2020.

AngloGold Ashanti says it is working closely with government and community stakeholders to ensure that the Obuasi mine is developed sustainably, fuelling growth for Ghana and benefitting the communities around the mine. A committee, including local stakeholders and regulators, has been created to track execution of the reclamation of the mine site and the mine will also be contributing $2/oz of gold produced to a Community Trust Fund, over its life, to facilitate development projects in the local area.

Some 80% of the capital thus far has been spent in-country, according to the Managing Director of the Obuasi Mine, Eric Asubonteng. “Ghanaian companies have been given preference in the procurement of goods and services, from the large-value underground mining contract all the way to catering and security contracts,” the company said.

Employment has also prioritised Ghanaians from the immediate area around the mine wherever possible, with Ghanaians from elsewhere in the country next in line for recruitment in available roles.

Newmont Goldcorp delivers the hat-trick with Ahafo mill expansion

Newmont Goldcorp has announced that the Ahafo mill expansion in Ghana achieved commercial production, on schedule and within budget for around $175 million.

Combined with the Subika Underground operation, which was successfully completed in November 2018, the mill expansion is expected to increase Ahafo’s average annual gold production to between 550,000-650,000 oz/y through 2024, while lowering life-of-mine processing costs.

“The Ahafo mill expansion represents our third profitable project delivered on schedule and within budget in 2019, along with the Tanami power project in Australia and the Borden mine in Canada,” said Tom Palmer, President and Chief Executive Officer. “The mill expansion is expected to generate an internal rate of return of more than 20% at a $1,200 gold price, while also extending profitable production at Ahafo through at least 2029.”

Features and benefits of the mill expansion include:

  • Increasing mill capacity at Ahafo by more than 50% to nearly 10 Mt/y with the addition of a crusher, grinding mill and leach tanks to the circuit;
  • Adding annual gold production of 75,000 to 100,000 oz/y for the first five full years beginning in 2020;
  • Accelerating efficient processing of ore from stockpiles and the Subika underground mine, as well as harder, lower-grade ore from Ahafo’s existing pits; and
  • Supporting profitable development of Ahafo’s highly prospective underground resources, which continue to demonstrate considerable upside.

Ahafo is expected to deliver record production this year – with improved costs – driven by higher grades from the Subika open pit, a full year of mining from the Subika underground mine and the completion of the Ahafo mill expansion.

Commercial production began at Ahafo in 2006, and, in 2018, the operation sold 436,000 oz of gold at all-in sustaining costs of $864 per ounce.