Tag Archives: narrow vein mining

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

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 using SR drive and KESS has previously been tested at OZ Minerals’ Prominent Hill copper-gold mine in South Australia, in addition to 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

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

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

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.

Paus releases new PMKM 8030 mining dump truck for narrow vein market

Germany-based Paus has released a new 16 t payload underground dump truck suitable for the narrow vein mining market.

The brand-new PMKM 8030 dump truck is one of most compact and powerful machines in its class, according to Paus, coming with EU Stage V/US Tier 4 Final engine options from Cummins and Caterpillar with up to 190 kW of power.

Paus explained: “Whereas the well established sister machine, type PMKM 8010, is a machine with less width at increased length and height, the new PMKM 8030 comes up with a broader, shorter and narrow design at a reduced loading height and with improved driving characteristics due to the lowered centre of gravity, bigger tyres and new axles with an integrated oscillation.”

A more powerful driveline and increased performance at reduced lifting and tipping times means the overall cycle time has been reduced significantly, according to the company.

The PMKM 8030 has an 8 cu.m dump box, a mining safety package including ROPS/FOPS protection and SAHR brakes, plus a new spacious, comfortable cab with 90° rotating driver’s seat.

Options for the dump truck include an ‘HD’ dump body, ‘LD’ dump body, and tailgate for dump body. The machine also has a data communication interface through PausConnect, the OEM’s lifecycle cost monitoring solution. It also operates as standard in temperatures ranging from -20°C up to 50°C.

Further state-of-the-art safety equipment like a button for brake test, three-point seat belt, seat belt and/or seat contact monitoring, different HRD on-board fire extinguishing systems, bird view camera, tyre pressure monitoring, gas monitoring system and others are available as an option.

“The selection of new components, the arrangement and a variety of options available along with the machine unveil the new PMKM 8030 as a more durable, more efficient and more easy to maintain machine for first and foremost economic use in underground mining,” Paus concluded.

Redpath puts Australia’s first Sandvik DD212 into operation at Silver Lake’s Rothsay

Redpath Australia says it has taken delivery of the first Sandvik DD212 production drill in Australia, putting it into action at Silver Lake Resources’ Rothsay gold mine in Western Australia.

The DD212 is a single-boom, electro-hydraulic drill for mining development and production and has been highly anticipated in the Australian narrow-vein market, Redpath says.

Redpath Australia’s Plant Manager, Chris Riethmuller, said the contractor specifically needed a rig that could drill in a 2 x 3 m drive and was able to drill within 100 mm of each wall to minimise dilution and increase recovery.

“Sandvik Mining and Rock Solutions stepped up to the challenge to the extent of redesigning the boom configuration to accommodate the request,” he said. “We then challenged them further and requested a 12-rod carousel be fitted to both of the rigs we have ordered. Sandvik had a plan in the pipeline for this carousel but agreed to fast track the project for us.”

The carousel has not yet been fitted to the first machine working at Rothsay due to scheduling requirements but is due to arrive in June, according to Riethmuller, who said the company is looking forward to taking advantage of the increased safety and expected productivity gain this tool will deliver.

In January, Sandvik announced the introduction of the DD212 rig, an upgrade of the Sandvik DD210 development drill rig, which is designed for narrow-vein operations.

Redpath, back in April 2020, announced it had been awarded a contract to carry out underground mining services at Rothsay.

Nippon Dragon refining thermal fragmentation process at Rocmec 1

Nippon Dragon Resources, a pioneer of the innovative thermal fragmentation mining process, says it has begun transforming its flagship gold property Rocmec 1, in Quebec, Canada, into a dynamic mine through investments in exploration, development, infrastructure and equipment.

In January, the company produced 1,000 t of mineralised material from the project. With the implementation of strict grade control procedures, the samples returned average grades of 6.5 g/t Au.

Nippon says plans have been completed to ramp up production to 3,000 t/mth within the next six months.

Mining at Rocmec 1 is based on state-of-the-art technology that integrates management and planning processes into digital platforms for project control and reporting, the company says. While it is currently finalising agreements with third-party milling facilities to readily bring bullion to market, its plans are to build a processing facility underground at Rocmec 1.

“Through the use of a completely mechanised thermal fragmentation extraction process, highly concentrated mineralised material is produced with minimum dilution,” the company explained. “Minimum mining waste is produced, and all waste material is stored underground, with zero environmental impact. Mine water is also recycled, drastically reducing our environmental footprint.”

Nippon has an exclusive licence for the thermal fragmentation mining process for narrow vein mining. The process involves drilling a series of 6 in (15 cm) pilot holes into the vein with a conventional drill. Thermal fragmentation (thermal head, compressed air and water) is then inserted and spalls the rock, quickly increasing the diameter of the hole to 30-110 cm. After this, ore can be extracted in 0-13 mm fragments. The leftover rock between fragmented holes is then broken to recover the remaining ore.

The proposed development plan at Rocmec 1 is based on the company’s permit to extract up to 44,000 t of mineralised material underground from its mining lease. The company says it is working on preparing and gathering the required information for the various government agencies and authorities to go beyond the permitted 44,000 t.

Alongside this work at Rocmec 1, Nippon says it has established a series of agreements with “renowned engineerin firms” to provide engineering services and support to operations. Service agreements have also been made with organisations to provide mining supplies and equipment maintenance services, it said.

The development and production equipment fleet has also been recently upgraded to meet the production targets, it said. Nippon has, in particular, optimised its thermal fragmentation units to permit full recovery of its narrow vein mineralised material economically and with minimum dilution.

LGA brings in narrow-vein mining specialist for Second Fortune gold project work

Linden Gold Alliance Pty Ltd says it has awarded a two-year A$45.7 million ($36.4 million) contract to Mako Mining for carrying out underground mining services at the Second Fortune gold project in Western Australia.

Mako is a specialist narrow-vein underground mining contractor with a proven track record of successfully mining narrow-vein orebodies and has held an ongoing 10-year contract at Western Areas Forrestania nickel project, also in Western Australia, LGA said.

“Mako Mining’s performance at Forrestania has included consistently meeting production and development targets whilst maintaining an enviable safety record with zero LTIs recorded since the company’s inception,” the company added.

The contractor has an extensive fleet of narrow-vein underground equipment, coupled with the required management and operator skill sets to ensure productivities are maximised, LGA believes.

“Along with LGA’s extensive technical expertise in narrow-vein gold mining, this alliance of companies will provide the project with the best opportunity to exploit this terrific high-grade narrow-vein resource,” the company said.

Mako mobilised to Second Fortune during November to commence underground works in December.

LGA’s General Manager of Operations, Andrew Rich, said: “The appointment of a leading narrow-vein underground mining contractor is an exciting time for both companies and allows LGA to continue its development plans to exploit the resource at Second Fortune in a safe, efficient and productive manner.”

LGA acquired Second Fortune in September 2020 from Anova Metals Ltd with dewatering and rehabilitation completed during the December quarter. First ore production is expected during March 2021.

The Second Fortune project area was originally mined during 1941 to 1988 from a small open pit and underground via shaft and handheld methods. Anova acquired the project in 2017 and completed infrastructure upgrades and Stage 1 of underground mechanised mine development, including dewatering of historic workings and portal establishment. Following Stage 1 completion, the mine was put into care and maintenance.

Sandvik advances narrow-vein drilling options with new DD212 rig

Sandvik Mining and Rock Solutions has introduced a new compact and intelligent single-boom electro-hydraulic drill for tunneling and mining development in narrow-vein drifts.

The Sandvik DD212 is an upgrade of the Sandvik DD210 development drill rig, and is designed for narrow-vein operations. It delivers both high level productivity and low cost of ownership, the mining OEM says.

Based on factory and field tests, the Sandvik DD212 delivers an up to 20% reduction in boom positioning time per face and a circa-15% improvement in drill penetration rate. Its 3% improved pull out ratio, meanwhile, can result in an up to 10 cm greater advance per face when compared with similar equipment.

The machine reached 93% mechanical availability during its mine site test period, accumulating 300 hours of percussion drilling within two-and-a-half months of operation.

“The drill provides great performance with net penetration rate, drill quality and rock tools improvements with zero drill rods jammed during the test period,” Sandvik added.

Among the new features are a drilling control system, the THC562, which provides torque control and reaming hole selection. This enables the DD212 to provide increased drilling performance, while reducing the wear on both the rock drill and rock tools.

The SB20i intelligent boom is used for accurate hole electronic positioning, which enables the precise and fast navigation of drill feed and tool, with automatic parallelism and instrumentation for hole angle measurements, Sandvik says. The boom offers a large face drill coverage from 6-25 m² thanks to the 1 m boom extension and the two narrow-vein type rotation actuators.

The development drill has an extended, 12 ft (3.7 m) TF feed rod, which optimises the advance/round, while its RDX5 rock drill provides a fast drilling cycle time and low operating costs.

The specific compact and versatile CFX telescopic feed, meanwhile, can retract from 12 ft to 6 ft (1.8 m), enhancing multipurpose operation in small tunnel sizes of 2.5 m x 2.5 m to 3.5 m x 3.5 m.

“The DD212 delivers accurate face drilling, cross cutting and bolting and enables mines to open smaller tunnel sections, reducing overbreak, dilution and drilling costs,” Sandvik says.

The company added: “The new DD212 brings operational safety and versatility for tackling different applications, precise electronic positioning, ergonomic operator interface and data monitoring, all leading to a superior pull-out ratio and reduced tool consumption, ensuring that the new DD212 delivers the best fit in narrow-vein drilling.”

K92 Mining continues to add new equipment at expanding Kainantu gold mine

K92 Mining, despite the onset of COVID-19, has made significant progress on its plans to increase production at its Kainantu gold mine in Papua New Guinea.

In March 2020, Kainantu achieved a major milestone, commencing the first long hole stope using the modified AVOCA method. This method is ideal for narrow vein/lens higher-grade stopes and can provide higher tonnages through continuous fill and blasting, as well as improved dilution control, according to the company.

The commencement of this new mining method is significant since previous mining has been exclusively from lower productivity and higher-cost development and cut and fill stoping, K92 said.

The first stope was from the K1 Vein and, to date, long hole stoping activities have performed in-line with design and have been increasing, providing a notable positive impact on operational flexibility, the company added.

Mining operations, which have been expanding in line with the 2019 decision to expand throughput to 400,000 t/y, from 200,000 t/y, have also benefited from further additions to the mining fleet.

The Papua New Guinea COVID-19 State of Emergency declared on March 20, 2020, saw limited impact to freight, with the arrival of a third Sandvik LH517i underground LHD loader with AutoMine® capabilities, a third CAT AD45B 45 t underground truck and two Terex Articulated surface haul trucks, since its declaration. The Government of Papua New Guinea ended the COVID-19 State of Emergency on June 16, resulting in a further easing of some of the restrictions, particularly around domestic movement.

“The equipment joins a significantly expanded and modernised fleet since the decision to proceed with the Stage 2 Expansion on March 13, 2019,” K92 said.

Back in January, the company said it expected a Sandvik DS421 cable bolter to arrive this quarter, alongside a modular batching plant. The company said earlier this month that this unit (pictured), as well as three new and high powered diamond drill rigs were in transit to the mine.

Twin incline activities have recently recommenced at Kainantu with the easing of restrictions from the state of emergency. Ground support for the portal is also underway, with portalling and the installation of steel sets expected to commence in the first half of the September quarter, the company said.

The process plant, meanwhile, has achieved multiple daily throughput records during the June quarter, significantly exceeding the 200,000 t/y, or circa-550 t/d nameplate capacity, with over 700 t/d achieved on multiple occasions.

“The strong performance of the process plant and underground mine to date are expected to result in gold-equivalent production exceeding March quarter output,” the company said.

The March quarter saw K92 produce 19,240 oz of gold, 339,993 lb (154 t) of copper and 6,937 oz of silver for a total of 19,934 gold-equivalent ounces, representing the second highest quarter on record. Gold-equivalent production in 2019 was 82,256 oz, with 115,000-125,000 oz of gold-equivalent scheduled in 2020.

Preparations are also being made to recommence Stage 2 process plant commissioning in the near term, to double plant throughput capacity to 400,000 t/y. All the equipment is installed, and commissioning is expected to commence in first half of the September quarter, with completion targeted at the end of that three-month period, K92 said.

John Lewins, K92 Chief Executive Officer and Director, added that a Stage 3 Expansion preliminary economic assessment is planned for July.