Tag Archives: narrow vein mining

Sandvik introduces ‘industry’s most advanced’ narrow vein underground drill

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Sandvik Mining and Rock Solutions is introducing the Sandvik DD212i, its first intelligent i-series narrow vein drill and, it says, the industry’s most advanced underground drill of its type.

The Sandvik DD212i is a compact single-boom jumbo with a new carrier and updated design, offering improved productivity, drilling accuracy, intelligence, versatility and easy integration into operations, the company claims. Optimal in narrow vein and medium-sized drifts, Sandvik DD212i ensures more tonnes and maximum profitability, as well as operational efficiency with precise electronic positioning and instrumentation for hole measurements.

Jean-Christophe Goiffon, Low Profile and Narrow Vein Product Manager for Underground Drilling at Sandvik Mining and Rock Solutions, said: “[The] Sandvik DD212i was developed for mines looking for compact equipment with better connectivity and data collection capabilities. Despite its small size, [the] Sandvik DD212i offers increased productivity and drilling accuracy in challenging operations with deeper and narrower orebodies.”

New features available with the Sandvik DD212i include intelligent drilling control, a new narrow vein carrier, SB20i instrumented boom, Sandvik RDX5 rock drills, safer ROPS/FOPS cabin and canopy and versatility in drilling applications. Scalable automation packages will offer a wide range of features for automatic drilling and will help maximise the data collected, according to Sandvik.

These combined features enable increased penetration rates, better advance and better pull-out results compared with predecessors in Sandvik’s narrow vein offering. The total cost of ownership can also be reduced thanks to lower parts and consumables costs.

Sandvik is simultaneously introducing a new module of its Digital Driller™ training simulator for the Sandvik DD212i to train and upskill operators in advance.

“Many regions are experiencing reduced availability of skilled labour, and our customers are interested in easy and fast training solutions with automated functions that enable higher performance for new and low-skilled operators,” Goiffon said.

Operator feedback during field testing in Austria emphasized the short start-up period required thanks to the user-friendly control panels and display, and even compared he Sandvik DD212i drilling performance to that of the twin-boom Sandvik DD422i jumbo.

Sandvik will introduce more optional extras for Sandvik DD212i in the coming months, including Gold level automation and a longhole package specially designed for longhole drilling in narrow vein applications with minimum tunnel profile of 2 x 3 m, it says.

E-Tech evaluating Novamera’s surgical mining technologies for Eureka project

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E-Tech Resources Inc has signed a Memorandum of Understanding (MoU) with Novamera Inc to evaluate the use of surgical mining and Novamera’s technologies as the extraction method for its Eureka project in Namibia.

The MoU sets out a series of milestones that include a conceptual surgical mining economic desktop evaluation (commencing immediately), Guidance Tool calibration activities and a bulk sample. The parties are planning to initiate these activities over the next 12 months.

The solution could provide a more cost-effective and faster path to production, while also radically reducing environmental and social impact, E-Tech says. It aligns well with E-Tech’s values of being a sustainable and responsible company with the goal of supporting the green energy transition.

The Eureka project focuses on two rare earth elements (REEs), neodymium and praseodymium. The project’s mineralogy, processability and favourable logistics have the potential to make it one of the simplest and most accessible sources of REE supply to the global market, according to the company.

Todd Burlingame, E-Tech CEO, said: “E-Tech is advancing the development of the Eureka deposit by utilising innovative and leading-edge technology. The minerals of the future will require techniques and approaches that are in line with the ESG principles of their end use. We believe that Novamera’s technologies are revolutionary and E-Tech is thrilled to be at the forefront of exploring new mining methods.

“We are committed to finding sustainable and cost-efficient ways to mine the materials essential for building a low carbon economy, while also protecting and preserving the environment.”

Dustin Angelo, Novamera CEO, said: “We are excited to be working with E-Tech and demonstrating the capabilities of our surgical mining technologies. Mining companies like E-Tech are looking for solutions to bring deposits into production with a smaller environmental footprint than that of conventional mining methods. The willingness to look at a different business model will open more strategic options to generate value for their shareholders and realise positive cash flow sooner for a project.”

Novamera’s proprietary hardware and software seamlessly combine with conventional drilling equipment, allowing mining companies to surgically extract deposits while minimising dilution, according to the company. Real-time data, machine learning and production analytics drive the ‘surgical mining cycle’ to make extraction of complex, narrow-vein deposits not only viable but highly profitable.

A low capital expenditure solution requiring minimal mine development, surgical mining presents miners with a flexible, scalable mining method that can help get into ore quickly with small-scale deposits, it says.

Working together with conventional drilling equipment and operations, the solution generates circa-95% less waste and less than half the greenhouse gas emissions of selective mining methods, according to Novamera. In addition, a closed-loop system is employed to minimise water discharge and real-time backfilling reduces environmental impact and tailings storage needs.

A 2021 proof of concept was designed to test the entire surgical mining system and process, which is made up of three steps. This includes drilling a hole with a standard NQ-sized diamond core rig and sending Novamera’s proprietary guidance tool down through the core barrel on wireline to image the orebody in high resolution and with close spacing; bringing in a large-diameter drill, coupled with the company’s course correction device and positioning control system, to drill to depth following the trajectory provided by the guidance tool and transporting the cuttings using reverse circulation air-lift assist; and backfilling the holes thereafter.

The latest in-field demonstration, completed in late 2022, took place in Baie Verte, Newfoundland, at the same Signal Gold-owned site (the Romeo and Juliet deposit). The trial highlighted the technical capabilities of the guidance tool, the operational impact of real-time data in a production setting and the economic potential of surgical mining, according to Novamera.

Carried out under the auspices of the Canada Mining Innovation Council (CMIC), the demonstration highlighted to the sponsors – OZ Minerals, Vale and an unnamed global gold producer among them – that the guidance tool was integral to effective surgical mining.

In terms of the next steps for the technologies, Angelo told IM back in June that the company was keen to fabricate a “course correction device” able to compensate for the impacts of gravity on drilling such holes and the rock dynamics at play, equip the drill rig with a 2-m-diameter cutting head (as opposed to the 1-m-diameter head used in the proof of concept), prove out the guidance tool at a number of sites to build up a “geological database” and then get to a full production test at a chosen mine site.

Such a mine site test was confirmed around this time after the Government of Canada announced the 24 recipients of support selected through the Mining Innovation Commercialization Accelerator (MICA) Network’s second call for proposals. Novamera was named within this select pool, with the government granting it C$850,005 ($643,984) for a project to deploy its surgical mining technologies at the Hammerdown mine site, in Newfoundland, Canada, a site owned by Maritime Resources.

Novamera plots path forward for surgical mining technologies

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Having completed a proof of concept of its entire surgical mining technologies portfolio in 2021, Novamera has furthered its credentials in the narrow-vein mining space by proving out its proprietary guidance tool in the same setting and testing out the ability to transport the concept to an underground mining environment.

Novamera’s proprietary hardware and software seamlessly combine with conventional drilling equipment, allowing mining companies to surgically extract deposits while minimising dilution, according to the company. Real-time data, machine learning and production analytics drive the ‘surgical mining cycle’ to make extraction of complex, narrow-vein deposits not only viable but highly profitable.

A low capital expenditure solution requiring minimal mine development, surgical mining presents miners with a flexible, scalable mining method that can help get into ore quickly with small-scale deposits, it says.

Working together with conventional drilling equipment and operations, the solution generates circa-95% less waste and less than half the greenhouse gas emissions of selective mining methods, according to Novamera. In addition, a closed-loop system is employed to minimise water discharge and real-time backfilling reduces environmental impact and tailings storage needs.

The 2021 proof of concept was designed to test the entire surgical mining system and process, which is made up of three steps. This includes drilling a hole with a standard NQ-sized diamond core rig and sending Novamera’s proprietary guidance tool down through the core barrel on wireline to image the orebody in high resolution and with close spacing; bringing in a large-diameter drill, coupled with the company’s course correction device and positioning control system, to drill to depth following the trajectory provided by the guidance tool and transporting the cuttings using reverse circulation air-lift assist; and backfilling the holes thereafter.

The latest in-field demonstration, completed in late 2022, took place in Baie Verte, Newfoundland, at the same Signal Gold-owned site (the Romeo and Juliet deposit). The trial highlighted the technical capabilities of the guidance tool, the operational impact of real-time data in a production setting and the economic potential of surgical mining, according to Novamera.

Carried out under the auspices of the Canada Mining Innovation Council (CMIC), the demonstration highlighted to the sponsors – OZ Minerals, Vale and an unnamed global gold producer among them – that the guidance tool was integral to effective surgical mining.

Dustin Angelo, CEO of Novamera, expanded on this.

“Throughout the technology development, we have had questions or statements about the ability to carry out the type of narrow-vein mining we are talking about by simply using a large diameter drill rig to extract the orebody following a conventional resource model,” he told IM. “The typical spacing a narrow-vein orebody is drilled on – traditional cross-cutting holes associated with exploration and infill work – is too wide to get the resolution needed for an exact picture of the orebody geometry.

“What we were able to demonstrate in the latest trial is that you need a tool like ours to collect, in real time, the amount of data required to accurately extract the orebody in question.”

Novamera demonstrated this in a March webinar, which highlighted the existing infill model at the Romeo and Julie deposit implied a large-diameter drill hole could be drilled on a 62° dip angle to accurately extract the orebody.

“In actuality when we imaged the hole and used our guidance tool, it suggested the orebody was on a 67° dip angle,” Angelo said. “We validated this assessment with data and then reconciled the results to show the impact.”

The original drill hole dip angle coordinates would have resulted in only 60% of the orebody being extracted, whereas Novamera’s guidance tool-aided drilling obtained 87% of the orebody.

“At the same time, the data coming back allowed us to locate where the other 13% would be, allowing the company to pick the remainder up with the next hole,” Angelo said.

Also part of the CMIC consortium, the company brought the guidance tool to an underground mine and was able to successfully operate it in that underground environment.

“We had never been underground, so we simply wanted to show we could take the tool underground, operate it and gather data in real time,” Angelo said.

Able to break the unit down into two pieces and mount the technology in stages on the drill rig, this was a pivotal demonstration for the company, opening up further possibilities with its solution.

“Novamera’s technologies can go underground; it is the large diameter drill we are piggybacking off that has issues due to its sheer size,” Angelo said. “We are working with OEMs and contractors to augment existing large diameter drilling equipment so it can be easily deployed in the confines of an underground deposit for the surgical mining application.”

In terms of the next steps for the technologies, Angelo was keen to fabricate a “course correction device” able to compensate for the impacts of gravity on drilling such holes and the rock dynamics at play, equip the drill rig with a 2-m-diameter cutting head (as opposed to the 1-m-diameter head used in the proof of concept), prove out the guidance tool at a number of sites to build up a “geological database” and then get to a full production test at a chosen mine site.

Such a mine site test was recently confirmed after the Government of Canada announced the 24 recipients of support selected through the Mining Innovation Commercialization Accelerator (MICA) Network’s second call for proposals. Novamera was named within this select pool, with the government granting it C$850,005 ($643,984) for a project to deploy its surgical mining technologies at the Hammerdown mine site, in Newfoundland, Canada, a site owned by Maritime Resources.

This project, which has a budget of circa-C$8 million – will see the company test out its technologies on a vein located outside the current proposed open-pit mine plan, demonstrating one use case where surgical mining can help mining companies add production to supplement the conventional method being employed.

Angelo said of such testing: “When we get to this point, it is no longer about simply a proof of concept, it is about demonstrating the capabilities and value of our technologies to enable surgical mining by reconciling the grade and tonnes associated with that mining exercise against an already established resource model.

“This is where we will really generate significant interest from the mining community, when we can show that we can help mining companies add production and extend mine life from currently uneconomic, steeply-dipping narrow vein deposits or zones in their mineral resource portfolio.”

Sandvik LH202 joins the Toro family and moves to Stage V engine configuration

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Sandvik is upgrading its three–tonne loader for narrow-vein applications, offering the newly rebranded Toro™ LH202 with an EU Stage V compliant engine.

The Toro LH202 loader is, Sandvik says, a reliable workhorse designed specifically for narrow-vein underground mining applications. With its robust structure, very compact size and three–tonne payload capacity, the loader is tailored to meet productivity targets in challenging environments and is optimised to fit tunnel widths between 2 m and 2.5 m, to reduce dilution.

In addition to underground narrow-vein mines, the Toro LH202 is suited for tunnelling.

Due to its relatively light weight and the possibility to disassemble the equipment for transport, the Toro LH202 is ideal for projects located in remote areas with challenging access, according to the company.

The new Stage V engine from Deutz on board the machine delivers best in class MSHA and CANMET ventilation rates with ultra-low-sulphur diesel fuel while maintaining performance and fuel efficiency, Sandvik says. The Stage V engine aftertreatment is a diesel particulate filter (DPF), which uses passive regeneration during normal engine operation to oxidise the soot trapped in the DPF core. The other available engine configuration is a 50 kW air-cooled turbocharged direct injection diesel engine, also from the engine manufacturer Deutz, with catalytic purifier and muffler, the company added

In addition to traditional fossil diesel fuel, the Stage V engine can use paraffinic diesel fuels, meeting the requirements of EN 15940, which reduces emissions of CO, CO2, HC, NOx and diesel particulates. Further, these engines can also use biofuel blends (such as FAME) meeting requirements of EN 590. Higher blends may also be used after consulting with Sandvik representatives, the company says.

GHH delivers first LF-7 LHD to Indian market

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A month after announcing the first delivery of a Tembo 4×4 electric light vehicle to India, GHH says it has now shipped the first LF-7 LHD to the country.

The vehicle was shown at the Mining Expo in Kolkata, in April, with GHH then arranging the onward transport to the unnamed launch customer, who also ordered further machines from the OEM.

The previously delivered Tembo 4×4 ELV, which went to Hindustan Zinc, is an electric multi-purpose light duty vehicle based on the Toyota Land Cruiser and Hilux models. It is available in many versions ranging from a pickup truck to a passenger transporter (10 seats). GHH is a regional distributor of the vehicle.

According to GHH, the LF-7 currently offers the largest bucket, most powerful engine and best climb performance in its class.

It carries 7 tonnes or 3.6 cu.m, is 8.9-m long in driving position, 2.24 m-wide at the bucket and 2.2-m high at the cab when fully loaded. This makes the LF-7 suitable for narrow-vein operations, as well. The loader is powered by a 164 kW Cummins diesel engine and complies with Tier 3/4 and EU Stage V emissions standards, GHH says.

Maintenance requirements are eased with the addition of GHH InSiTE software, which allows vehicle data to be called upon in real time and evaluated.

Novamera carries out first field trial of SMD narrow-vein mining process

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Novamera says it has completed a very successful field trial of Sustainable Mining by Drilling (SMD) at the Anaconda Mining-owned Romeo and Juliet narrow vein gold deposit in Newfoundland, Canada.

The company, back in July, closed a C$5 million ($4 million) Series A financing round, providing the necessary funds to carry out the first full field trial of SMD.

This proof of concept was designed to test the entire SMD system and process, which combines industry-proven, directional drilling equipment and high-resolution, downhole imaging with transformational innovations, smart systems and data analytics. The result, Novamera says, is a two-pass process that identifies vein shape and is highly flexible to changes in vein geometry; with a selective, surgically-accurate mining process that’s clean, efficient and offers the potential for low capital expenditure with high return.

Komatsu brings hybrid drive, narrow vein LHDs to Australian hard-rock market

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Komatsu Australia says it has, for the first time, entered the hard-rock underground mining market with a concerted solution made up of two larger hybrid LHDs and two diesel-powered narrow-vein loaders.

Two high-tech hybrid drive underground loaders, equipped with durable independent electric motors in each wheel, headline this substantial investment by Komatsu to provide a complete service solution to miners and contractors, it said.

“Providing hard-rock miners with reliable underground loaders is part of a broader understanding of the need to assist their overall productivity in the face of global competition,” Joshua Foale, Product Manager Mining, Komatsu Australia, said.

The hybrid Komatsu WX22H and WX18H LHDs each claim to be the lowest total operating costs in their class.

Meanwhile, Komatsu’s analysis shows the conventionally powered Komatsu WX07 7 t loader (pictured) is 14% more productive than any other machine in its category. The WX04 4 t LHD offers 20% more breakout force in its class, based on published information.

Komatsu hybrid loaders

Komatsu’s WX22H and smaller WX18H achieve up to 20% increase in tonnes moved, compared with conventionally powered loaders, the OEM said. They also have an up to 20% decrease in fuel costs, based on operating trials.

An independent life cycle analysis identified a 30% reduction in operating costs, compared with their conventionally powered counterparts.

Improved work cycle performance is achieved by use of high efficiency electric traction motors in each wheel, making conventional mechanical power drive redundant, resulting in substantial reductions in operating costs, Komatsu said.

The Komatsu WX18H produces 280 kW

The Kinetic Energy Storage System (KESS) is at the heart of the switched reluctance hybrid drive, which captures and reuses braking energy from each of the four wheels. Heat-energy generated when the machine stops abruptly at the dig face is captured by the bi-directional KESS loop instead of being lost to the atmosphere.

KESS stores and releases 3 MJ of energy, supplementing power from the conventional diesel engine for greater acceleration to maximise cycle performance, according to the company.

A smart traction system provides smoother acceleration and results in less tyre wear and component degradation. It generates less inertia at each stop, significantly reducing potential damage to the drive train.

Fewer underground emissions, lower heat rejection and greater operator comfort are all intended benefits of the hybrid system.

Komatsu’s 22 tonne WX22H produces 320 kW, with the smaller WX18H producing 280 kW.

Both engines are rated to the strictest EU Stage V requirements for emission control, and both use the same KESS, capable of delivering 410 kW, effectively doubling power delivery on demand.

A Joy 22HD hybrid LHD (now the WX22H) using SR drive and KESS has previously been tested at OZ Minerals’ Prominent Hill copper-gold mine in South Australia, in addition to a WX18H having been trialled at Codelco’s El Teniente underground mine in Chile.

Narrow-vein focus

Komatsu has designed the WX04 and WX07 for maximum productivity, with the WX07 a forerunner of a new breed of LHDs using improved chassis, power train and operator cabin environment.

Large capacity fuel tanks – 243 litres in the case of the WX07 – allows longer operational cycles between refuelling, while the cabin access, visibility and ergonomics have been optimised. Critical service points have been placed at ground level to minimise the need for technicians to climb or use ladders to reach key areas, the company said.

A new more efficient bucket design enables greater penetration into a load pile for fast bucket filling.

The Komatsu WX04 delivers 97 kW and the WX07 delivers 160 kW.

Komatsu says it range of hard-rock mining machines establishes new standards of strength and durability.

“In developing our machines, we have been specific in providing protection for critical structural components, linkages and joints,” Foale said. “Reliability has been a paramount consideration in the design of long-life moving parts.

“In the case of our hybrid drive machines, there are no commutators, brushes or rotor windings to replace, and our wiring systems are double insulated.”

Novamera finds funds for first full field trial of Sustainable Mining by Drilling tech

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Novamera has closed its C$5 million ($4 million) Series A financing round, providing the necessary funds to carry out the first full field trial of its Sustainable Mining by Drilling (SMD) solution for narrow-vein mining.

BDC Capital’s Industrial Innovation Venture Fund was the lead investor and Chrysalix Venture Capital also participated with a follow-on investment through the Chrysalix RoboValley Fund.

The field trial, which is taking place at Anaconda Mining’s project site in Newfoundland, Canada, has commenced and will be ongoing until the end of November. The company says it is carrying out a proof of concept, testing the entire SMD system and process.

Dustin Angelo, President and CEO of Novamera, said: “The financing, along with the non-repayable funding from Sustainable Development Technology Canada, will help us develop the first generation SMD system and position the company to be the global leader in precision mining. The mining industry faces many challenges that require more sustainable and environmentally-friendly solutions and SMD will be an economically viable option to extract narrow vein deposits with minimal waste and disturbance.”

Novamera says it is developing “keyhole surgery” for mining, an innovative clean technology and process that will be able to mine the numerous small-scale narrow vein mineral deposits found worldwide more safely, economically and sustainably using pilot hole diamond drilling and downhole directional sensors with machine-learning algorithms to to identify vein/host rock interfaces. Then it will use industry proven drilling technology – a variant of conventional Pile Top RCD drills used successfully by the construction industry followed by a form of reverse circulation drilling – to extract the ore.

Hochschild Mining plans electric equipment fleet expansion

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Hochschild Mining, in its 2020 sustainability report, has flagged the arrival of further electric vehicles at its mine sites in Latin America as it looks to cut emissions and reduce ventilation requirements at its underground operations.

The company said it has been operating six electric mine vehicles, purchased between 2017 and 2018, at its San Jose narrow-vein silver mine in Argentina for some time. This includes an Aramine L130E miniLoader® (pictured), a 1-2 t capacity electric LHD suitable for narrow-vein mining applications with a 0.5-0.75 cu.m bucket and an operating width of 1,046 mm. The miniLoader L130E is fitted with a cable reel designed for tramming off the mine power grid. The company also has an Aramine L150E tethered-electric LHD in its fleet.

In 2020, Hochschild added a battery-electric vehicle to the mix at its Inmaculada gold-silver narrow-vein operation in Peru.

It said: “In 2020, we piloted the use of the first electric vehicle at Inmaculada for liquid waste management. Working in partnership with our on-site waste management contractor, the project is the first of its kind in Latin America and, if successful, will be scaled up throughout 2021.”

Hochschild told IM that its waste management contractor, Resiter, was operating an Alke ATX 330EH battery-electric off-road light utility vehicle with a flatbed for liquid waste. This vehicle is fitted with a tank and suction motor to be used to clean portable toilets throughout the mine site.

“It is also worth noting that the trials carried out indicate some modifications are needed for it to be able to be used in the irregular surfaces at Inmaculada, and it is still under investigation by the supplier,” the company said.

Hochschild added in the report: “In 2021, we hope to expand our electric fleet with the purchase of electric vehicles for use in larger underground chambers that will not only reduce our carbon footprint but will also cut ventilation costs.”

Scotgold boosts underground fleet at Cononish with DUX truck

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Scotgold, as it looks to further enhance safe production at its Cononish gold-silver mine in Scotland, has added another DUX underground truck to its fleet.

The second DUX truck at Cononish is a DT-12N, a narrow vein version of the DT-12 produced by DUX that measures 1,625 mm wide, has an 11 t payload and a 6 cu.m capacity. The first DT-12N has been operating at the mine for some time.

In the company’s announcement on June 1, it said the mine has been producing both gold concentrate and gravity separated gold dore, following the resolution of various outstanding technical issues affecting the processing plant earlier in the year. The first shipment of concentrate was made on May 11, 2021, achieving a major milestone for the company. The mine poured first gold back in December 2020.

“We shipped 25 t of concentrate at an average of 182.4 g/t of gold, exceeding the target of 150 g/t, achieving maximum price within the agreed terms within the offtake agreement,” the company said. “Modest amounts of gravity gold dore was also produced and sent to refiners this month for further treatment.”

Scotgold said it is encouraged with the mine and process plant performance, although performance had been intermittent to date.

“On given days throughout April and May, both the mine and process plant have been achieving near design rates of production,” it said. “The company is also pleased with the quality of ore that has been mined and produced through the process plant.”

Scotgold says its focus is to further enhance safe production through consistency and stability of mine and process plant operations in parallel with the opening of multiple faces of ore in the underground mine itself.

“The current limited available number of ore faces does limit our immediate ability to focus on the highest-grade ore zones of the Cononish orebody,” it explained. “Having proved that the mine and processing plant can operate as designed, our focus is on reducing outages through more efficient management of spares and having further redundancy in our mining mobile fleet with the arrival of the second haulage DUX truck.”

This new DUX truck will be complemented by an existing fleet that includes an Epiroc T1D single-boom face drilling rig and Epiroc ST2G Scooptram LHD.

When ramped up, Cononish is expected to average annual gold production of 23,370 oz over a nine-year life of mine.