Tag Archives: narrow vein mining

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.

Fura Gems’ Coscuez mechanisation shift sees it invest in Resemin, Epiroc equipment

Fura Gems has completed the transition from artisanal to fully mechanised mining at its 76%-owned Coscuez mine, with a new mining fleet now working underground at the Colombia operation.

Following declaration of an NI 43-101 inferred mineral resource at Coscuez last year, which included a 3 Mt total grading 2 ct/t for 6 Mct contained, the company started working on a mechanisation plan.

This mine mechanisation program started in August 2019 and saw three underground declines developed from the main LAPAZ level to intersect the inferred resource body in the Santana, Ayata and the Miguel sectors.

The full program was completed in January 2020 and saw the company acquire modern equipment suitable for narrow vein-mining to increase mining capacity as compared with 2018, it said.

The new mining mechanised fleet includes a total of 12 mini-dumpers, with 4 t and 2 t capacities, one electrohydraulic jumbo drilling machine, three LHDs and three tractors, each of which are currently operational on site.

“With this addition, the Coscuez team has reduced manual drilling and eliminated manual loading and hauling operations,” the company said.

A spokesperson for the company confirmed to IM that the mini-dumpers, jumbo and at least one LHD are from Resemin, while another LHD was from Epiroc.

Another improvement the company introduced in 2019 was the implementation of a new active support system consisting of cement-grouted rock bolts, split sets, wire mesh, and shotcrete layers instead of the traditional passive rock support system based on timber sets.

These improvements helped the company mine a total of 31,963 t during 2019, representing a 109% increase on 2018’s mined total, Fura said.

Furthermore, two international consultants, Bisa and MiningOne, have been retained to complete two technical studies at Coscuez.

The first study is a geotechnical study for rock support and mining methods for different types and rock qualities, while the second study is focused on the design of current and mid-term mine ventilation system.

On top of acquiring mobile mining equipment, Fura, in 2019, installed a new 10 t/h pilot washing plant to help the washing process at Coscuez transition away from manual washing to a much more efficient process.

A new commercial washing plant with projected capacity of 100 t/h is currently being designed and is expected to be commissioned by the December quarter, it added.

ARMZ, Aramine partnership brings battery-powered narrow vein LHD to Russia

ARMZ Mining Machinery says it has become the first and only company in Russia and the CIS producing lithium-ion battery-powered mining equipment through a collaboration with Aramine.

The company, part of ARMZ Uranium Holding Co, has started producing the mining equipment in Krasnokamensk, in the Trans-Baikal Territory of Russia, at the site of Priargunsky Industrial Mining and Chemical Union (PIMCU, PJSC is a part of ARMZ Uranium Holding Co).

The project is being implemented under an industrial partnership agreement ARMZ Uranium Holding Co and France-based Aramine, signed in April 2019. As part of this pact, ARMZ Mining Machinery is the project operator.

ARMZ said the production from Krasnokamensk will cover the internal needs of ROSATOM State Atomic Energy Corp (of which ARMZ is a part of), and let the company enter foreign markets with competitive products.

The ARGO LHD 140B is designed specifically for underground work in narrow-vein deposits, according to ARMZ. Based off the design of the Aramine miniLoader L140B, it has a width of 1.1 m and a bucket carrying capacity of 1.3 t. A 50 kW engine and a lithium-ion battery pack provide high mobility and continuous operation for up to four hours; at the same time, offering low noise, minimal heat transfer and no gas contamination in the mine. The machine significantly outperforms the requirements of the Russian standards in industrial safety, according to ARMZ.

Ivan Kiselev, Director General of PIMCU, PJSC, said: “New LHD machines will let us efficiently and reliably carry out operations for the loading and transportation of ore inside the stopes. The transition to a new battery-powered narrow-vein equipment is an economically viable solution aimed at reducing operating costs and improving the quality of ore mining.”

Igor Semenov, Executive Director of ARMZ Mining Machinery, said the production of the ARGO LHD 140B means ARMZ Mining Machinery has become the first and only company in Russia and the CIS producing lithium-ion battery-powered mining equipment.

He explained: “We adapted the Aramine design and specifications to Russia standards, organised the technological process: in-house production of the structural frame, arms and dippers, assembly of body parts, installation of components, start-up and commissioning of machines. Our next step will be the localisation of the production of lithium-ion batteries and the expansion of the product line with other types of underground equipment.”

The first serial vehicles have already passed factory tests, according to ARMZ, and will be sent to the uranium mines of PIMCU, PJSC this month. In 2021, the ARGO LHD 140B will enter the Russia market and will then gradually become available in other countries within the customs union, it said.

Sandvik narrows down market for new class of underground drills

Sandvik Mining and Rock Technology has launched a new class of narrow size drills specifically aimed at the requirements of specialist mining companies as well as drill and blast contractors requiring safe, productive, mobile rigs for use in narrow vein and other confined areas.

The new 2711 class of drills are simple and safe to operate, with robust components, and provide an excellent performance to ownership cost ratio, according to the company.

The 2711 class drills have been developed to cater to the needs of certain mining and tunnelling operations.

Sandvik explained: “Selective mining methods and small tunnel developments have proved to be a good way to extract ore economically, and control the dilution when ore is distributed in narrow veins typically less than 2-3 m in width. Sandvik’s narrow size underground drills are thus designed specifically with the requirements of drilling narrow vein drifts and that of small tunnels projects in mind.”

The drills are also equipped with Sandvik’s Fleet Data Monitoring systems, enabling mines and tunnelling contractors to improve fleet performance and management.

The 2711 class is an ideal solution for specialist mines and drilling contractors looking for smarter control of ore dilution and increasing selective process in mining, according to Sandvik. The series consists of three drill types using a common platform covering different applications: namely development drilling DD2711, rock support bolting DS2711 and long hole production drilling DL2711 and DL2721.

The DD2711 (pictured) is a compact and flexible single boom electro-hydraulic jumbo for mining development and construction in small and medium size tunnels with a minimum cross section of 2.7 m x 2.7 m. The versatile boom delivers large coverage and fully automatic parallelism for fast and accurate face drilling, while 20 kW of drilling percussion power is provided through Sandvik’s HXL5 rock drill.

The rig is designed for underground hard-rock applications that require high capacity and reliability in development blast holes ranging from 3.7 m to 4.3 m in length.

The DS2711, meanwhile, is a one-man operated electro-hydraulic, fully mechanised bolter for rock reinforcement in underground hard-rock mines. The operator works from supported ground while protected under a FOPS-certified canopy structure. “Mechanisation of the bolting process ensures efficient, constant and durable rock bolts integrity,” Sandvik said.

The DS2711 provides “excellent” bolting performance to cost ratio for small and medium size tunnels with minimum cross section of 2.7 m (width) x 3 m (height), according to Sandvik.

“Designed with proven and reliable components, the DS2711 provides high reach, and is able to install all types of mechanised rock bolts ranging in length from 1.5 m to 2.4 m. It is in effect a small premium bolter, compact, mobile and designed for global needs.

The next addition to the range will happen in 2020 with Sandvik DL2711 & DL2721 long hole drills.

Sandvik concluded: “The new 2711 drill family provides, in one modular platform, accurate drilling with high performance, large coverage and drill capacity, with enhanced product safety and excellent mobility, tramming smoothly into small mining drifts and tunnels.

“The selected reliable components and simple electro-hydraulic systems are designed to be used in conjunction with Sandvik’s comprehensive range of underground drills, loaders and trucks, all being supported worldwide by the Sandvik network.”