Tag Archives: zinc

Vast sees path forward at Manaila with help of TOMRA’s XRT ore sorting solution

Vast Resources says it is continuing to evaluate the recommencement of production at its Manaila polymetallic mine in Romania and, as part of this process, has been working with TOMRA to assess the suitability of X-ray Transmission (XRT) ore sorting technology to optimise the mine’s production profile.

The assessment has demonstrated, to date, that by installing an XRT machine at the plant to pre concentrate ore at the pit, the technology would be highly effective for three main reasons:

  • A reduction in transportation costs as improved mass reduction would significantly reduce the material being transported from the mine to the processing plant;
  • A reduction in processing costs due to reducing the throughput at the plant; and
  • Higher-grade product being delivered to the plant.

It is anticipated that processing and transportation costs could be reduced by up to 55%, according to Vast.

“This cost reduction could have a dramatic impact on the mine’s financial performance,” the company says.

Samples from both types of mineralisation at Manaila, massive sulphide and disseminated sulphide, were sent to the TOMRA Test Centre in Wedel, Germany, to ascertain improved mass reduction and grade upgrade potential. Both mineralisation types showed amenability to the XRT process with metal content recovery on the massive sulphides at 95.4% for copper, 93.6% for lead and 95.2% for zinc in 71% of the mass, the company explains. The disseminated sulphides returned a metal content recovery of 84.2% for copper, 67.2% for lead and 84.4% for zinc in 35% of the mass.

The combined results show that 93.1% of copper, 82.2% of lead and 92.4% of zinc metal could be recovered in 45% of the mass when mining the polymetallic ore on a ratio of three tonnes disseminated sulphide to one tonne of massive sulphide, being the typical historical ratio of mining at Manaila.

Andrew Prelea, Chief Executive Officer of the Vast Resources, says: “These results clearly underpin our view that Manaila is economically viable, and the management team are considering various mine plan scenarios of bringing Manaila back into production.”

The 138.6 ha Manaila-Carlibaba exploration licence contains a JORC 2012 compliant measured and indicated resource of 3.6 Mt at 0.93% Cu, 0.29% Pb, 0.63% Zn, 0.23 g/t Au and 24.9 g/t Ag with inferred resources of 1 Mt at 1.1% Cu, 0.4% Pb, 0.84% Zn, 0.24 g/t Au and 29.2 g/t Ag. Comprising the Manaila polymetallic mine (currently on care and maintenance) and the Carlibaba extension project, Vast intends to establish a larger mining and processing facility at Manaila-Carlibaba which would eliminate the need for costly road transport of mined ore to the existing processing facility located at Iacobeni, around 30 km away.

Preliminary studies by the company indicate the potential for a new open-pit mine to exploit mineral resources to a depth of some 125 m below surface, and to simultaneously develop a smaller higher-grade underground mine below the open-pit mineral resources.

TOMRA XRT ore sorting test work delivers the goods at Kutcho’s copper-zinc project

Higher head grades and recoveries, a reduction in run-of-mine material reporting to the milling and flotation circuit, a smaller tailings management facility, and lower power and water demand are just some of the benefits to have come out of ore sorting test work at Kutcho Copper’s copper-zinc project in British Columbia, Canada.

Recent bulk sample test work was conducted to determine the effectiveness of using ore sorting technology from TOMRA Sorting Mining to improve the processed grade and reduce the mill feed tonnage of mineral resources at the project.

ABH Engineering Inc and TOMRA were commissioned to undertake this work to establish the amenability of Kutcho’s Main and Esso deposits to ore sorting using an X-ray Transmission (XRT) sensor. Two phases of test work, including a representative 0.75 t bulk sample derived from drill core, were undertaken at TOMRA Sorting Mining in Germany under the supervision of ABH Engineering.

“The ore sorting process helps concentrate the metals of commercial interest from the Kutcho deposit, which are principally associated with high density sulphide minerals,” Kutcho explained. “Rocks are individually scanned, and low grade (low density) waste material is selectively diverted away from downstream processing using compressed air jets. Preliminary test work on the sensitivity of the ore to a XRF sensor was also undertaken.”

The bulk sample tests conducted on a production-scale XRT ore sorter indicate that approximately 17% of the ROM material will be <12.5 mm in size and would therefore bypass the ore sorter and report directly to the milling and flotation circuit. Of the >12.5 mm feed, some 15% of the material reporting to the ore sorter was detected by the XRT sensors as being low grade or waste and will be rejected by the ore sorter, thereby reducing run-of-mine material reporting to the milling and flotation circuit by 13%. The overall recovery of metal (copper, zinc, silver and gold) reporting to the ore sorter is in the order of 99% (ie less than 1% of the metals of interest will be rejected by the ore sorter), Kutcho said.

Pre-sorting of the run-of-mine material by the ore sorter has the potential to reduce milling and flotation operating costs corresponding with the 13% rejection of low-grade material, it says. The commensurate increase in the head grade of the ore reporting to the flotation circuit has the potential to also result in improved metallurgical recoveries in the flotation circuit.

Additionally, it is anticipated that potential savings in capital and operating costs related to the smaller milling and flotation circuit will offset the costs associated with the ore sorter, according to the company. Savings will also be achieved by a reduction in the size of the tailings management facility. The optimally sized ore sorter reject waste material could be used as cemented rock backfill in the underground mines at both the Main and Esso deposits, resulting in further potential cost savings, Kutcho said.

Environmental benefits accruing to the project because of the introduction of ore sorting technology include a lower power and water demand, and a smaller tailings management facility, the company concluded.

Earlier this month, Kutcho said in a feasibility study progress report that it was considering open-pit mining for the majority of the Main deposit at Kutcho, allowing the company to capitalise on the high-grade, near-surface mineralisation, resulting in lower operating costs than underground mining. The remainder of the Main deposit and all the Esso deposit will continue to be evaluated assuming underground extraction by longitudinal longhole open stoping, it said.

The ore sorting test work was also being incorporated into the feasibility study design.

Boliden invests $160 million in leaching plant, underground repository at Rönnskär

Boliden has opened a new leaching plant and underground repository at its Rönnskär operations in Sweden as it looks to extract additional metal from residual materials at the smelter and store any remaining waste in a sustainable way.

For many years, residual materials from smelting processes containing copper, zinc and lead, among other elements, have been stored temporarily at the Rönnskär site.

These residual materials, together with future residues from production, will from this point pass through the newly built leaching plant where further metal extraction will take place. The remaining material will then be transported straight down to the underground repository, which is located about 350 m below the site.

This will see Rönnskär become the only copper smelter in the world with a long-term, sustainable on-site storage solution, according to Boliden.

Investments in the two facilities have amounted to SEK 1.4 billion ($160 million), Boliden says.

Daniel Peltonen, President Boliden Smelters, says: “Our aim is to extract as much metal as possible from our raw materials while ensuring the best achievable environmental and climate performance. The investments we have now made represent a new chapter in Rönnskär’s history in both of these areas.”

Rönnskär produced 226,000 t of copper, along with 33,000 of zinc clinker, 28,000 t of lead, 506,000 t of sulphuric acid, 524,000 kg of silver and 14,000 kg of gold last year, according to Boliden.

GR Engineering captures A$90 million of EPC contracts from Galena Mining

GR Engineering Services has been given the notice to proceed with the engineering, procurement and construction (EPC) of a 1.2 Mt/y lead sulphide flotation processing plant at Galena Mining Limited’s majority-owned Abra base metals project in Western Australia.

The contract, which follows a conditional agreement from February 2020, comes with a value of A$79.5 million ($59 million) to be realised predominantly in GR Engineering’s 2022 financial year.

In addition, Abra Mining has also awarded GR Engineering an EPC contract to relocate, refurbish and commission the Abra Mining-owned Higginsville paste plant. The value of this contract is a further A$10 million.

Geoff Jones, Managing Director, said: “GR Engineering looks forward to continuing its solid working relationship with the Abra Mining team on the delivery of the project and supporting Abra Mining as it becomes the next Australian base metals producer.”

New Century Resources and Senex Energy agree on natural gas supply pact

Senex Energy Ltd has announced a sales agreement involving around 7 PJ of natural gas over three years with New Century Resources Ltd.

New Century, which owns and operates the Century zinc mine in Queensland, Australia, will receive this natural gas supply from the Diamantina Power Station in Mount Isa (owned and operated by APA Group), with the 7 PJ being enough to operate the mine, it said.

Under the three-year agreement starting January 1, 2022, Senex will provide around 7 PJ of natural gas to support New Century’s processing operations at a fixed price, in line with current market levels. Senex will further supply around 1 PJ of additional natural gas at New Century’s election by mid-2022 in support of material increases in production levels associated with the potential development of existing in-situ deposits at Century.

Senex Managing Director and CEO, Ian Davies, said: “Century Mine generates significant state royalties and export earnings and is a critical project in the Queensland Government’s Strategic Blueprint for the North West Minerals Province.

“Senex also acknowledges APA as an important part of the value chain delivering energy to Mount Isa.”

Mastermyne looks for hard-rock exposure with PYBAR Mining buy

Mastermyne has accelerated its hard-rock mining strategy with an agreement to acquire PYBAR Mining Services in a cash and share deal that comes with an expected equity purchase price of A$47 million ($35 million).

The acquisition for PYBAR Holdings, owner of PYBAR Mining Services, will see Mastermyne, a metallurgical coal-focused contractor, exposed to PYBAR’s gold, copper, zinc and lead-related revenues, it said.

The deal is expected to create a leading Australia-based diversified mining services business with material scale, it said, adding that the combined group will have a A$1.7 billion-plus order book and an active tender pipeline of A$2.7 billion-plus after completion.

To reflect the changing make up of revenues, Mastermyne is proposing to change its name to Metarock Group Ltd.

Mastermyne MD and CEO, Tony Caruso, said: “The PYBAR acquisition is highly complementary to Mastermyne’s existing underground business and expands the combined group’s addressable markets to support ongoing growth, in addition to increasing the earnings resilience of the group by diversifying our commodity exposure.”

PYBAR Mining Services was established in 1993 and has gone on to become one of Australia’s largest underground mining contractors, serving the likes of Glencore (Black Rock mine), Diversified Minerals (Dargues gold mine), Gold Fields (Hamlet North mine), Evolution Mining (Cowal gold mine), OZ Minerals (Carrapateena) and more.

It has a large fleet of equipment, which includes Sandvik DD421 and DD421i series drills, a fleet of Cat R1300, R1700, R2900 and Sandvik LH621i LHDs, Cat AD45V-AD60 sized trucks and several Sandvik TH663s haul trucks. It provides services such as mine development, raiseboring, mine production, shotcreting, cable bolting and production drilling.

Mastermyne says PYBAR will continue to operate as an independent business unit within the group with the existing management team should the deal go through.

Subject to Mastermyne shareholder approval and the satisfaction or waiver of other conditions associated with the transaction, Mastermyne anticipates the deal completing by the end of the year.

Mine cooling solution set for 2022 start up at MMG’s Dugald River zinc mine

MMG’s Dugald River mine, in Queensland, Australia, is designing, supplying and installing a A$20 million ($14.7 million) cooling solution that, it says, will bring 9.5 MW of bulk air underground to facilitate ongoing zinc extraction.

MMG Dugald River General Manager, Tim Akroyd, said consistent temperature control is critical for the safety of the mine’s employees and contractors working in northwest Queensland’s hot climate.

“MMG has sourced a long-term refrigeration plant and ventilation system designed to deliver a safe work environment for our teams,” he said.

“To sustain mine production at a depth of 500 m below ground, cooling is essential and dramatically improves air quality. Mine ventilation firm, BBE Consulting, helped to scope options that are now spearheading MMG’s cooling works that are well underway, planned for completion by early 2022. The cooling system will be operational for the life of the mine, a period of up to 20-plus years.”

The scope of work covers the installation of 9.5 MW bulk air-cooling capacity, with a centralised refrigerative plant with distributing water circuits to the south and north mine. Water-cooled custom mine chillers, bulk air coolers, cooling towers and ancillary equipment are being deployed.

Water-cooled refrigeration machines have a lower capital project cost and use less power over a 20-year project life, when compared with air-cooled refrigeration machines, MMG said.

Suppliers and local contractors include CivilPlus Constructions, GNH Engineering, Bell Rural Contracting and Total Generators in Cloncurry to name just a few.

Aggreko ups the mine cooling ante with modular BAC10000s

Twenty years after establishing modular mine cooling solutions in Australia, Aggreko has released an offering for mines going deeper with its latest modular bulk air coolers (BACs).

These 40 ft (12.19 m) mobile BAC10000s coolers are “unique” and relatively new to the mine cooling market, according to Aggreko Australia-Pacific Managing Director, George Whyte.

“They are scalable, portable and boast three times the cooling capacity of our previous largest offering – the 20 ft long (about 6.09 m) containers,” he said.

Aggreko has delivered more than 50 mine cooling projects globally, and always draws on the experience of its engineering, procurement, construction and maintenance teams to stay at the forefront of technology, according to Whyte.

“Aggreko’s mining services pioneered mine cooling as a rental service 20 years ago as a result of mines looking for alternatives to capital refrigeration plants,” he said. “Previously mining companies would need to use capital to install built-in cooling systems which were not scalable, modular or as effective.

“In the past two decades we have witnessed mines becoming deeper and this has resulted in the need for larger cooling capacities and innovation. The need for deeper mines in increasingly remote locations, coupled with rising global temperatures, is forcing operation managers to seek affordable alternatives to cooling and ventilation systems.”

Aggreko Underground Cooling Sector Manager, Mitch Bevan, said the BAC10000s were used at a Western Australia mine last year and will soon arrive at a mine in New South Wales, Australia.

Bevan said part of the new modular BACs appeal were their simplicity and convenience when compared with purpose-built on-site cooling plants. The new BACs used a simple design involving pipes, chilled water and three axial fans – all comprised in a modular shipping container. He expected more mines globally would become interested in the company’s new product offering, particularly in regions such as Africa, Latin America and North America.

“The unit is more suited for larger installations and offers improved efficiency rather than using a large number of smaller BACs,” Bevan said.

“Capital refrigeration plants take a long time for mines to prepare for financially, as well as to install, whereas we can mobilise on relatively short notice. A rental option also provides a great deal of flexibility, which is often crucial for underground vent systems where it is difficult to predict the requirement year on year.”

Bevan said Aggreko re-engineered their cooling towers to come up with the 40 ft modular BAC10000s after anticipating there would be global demand for such an offering.

“Long running mines have continued to grow and their refrigeration requirement grows with the mine, so BACs are appealing as they can be scaled up or easily moved on-site,” he said.

“While mines are expanding, our clients are also focused on energy efficiency, and safer operation – such as more environmentally friendly refrigerants – and we are constantly working on new developments in these areas.

“The water-cooled BACs have less of an environmental impact seeing as the modular container sits on the ground’s surface and requires no serious ground modifications, such as concrete.

“The units only require water and power and, while some mines use diesel-generated power, as time goes on, that will shift to renewable energy. Our company has made major commitments to greener energy to help miners achieve net-zero emissions by 2050. That is why we are constantly exploring and investing in new technologies. Currently, our water-cooled chillers use half as much power as air-cooled options, which is part of their appeal, and we are the only rental company to provide such modular and scalable products.”

The BAC10000s have been successfully used at 29Metals’ Golden Grove mine – a high grade copper, zinc and precious metals mine, about 450 km northeast of Perth, which mills about 1.44 Mt/y.

When the mine underwent an expansion, which required almost two years to up-scale its permanent cooling plant, a quick and effective solution was needed in time for the 2020-21 summer, according to Aggreko. The power specialist was able to quickly supply the BAC10000s to install a 4.5 MWr water-cooled plant.

As well as water cooled refrigeration plants such as Aggreko’s 20 ft and 40 ft BACs, Aggreko also offers air cooled refrigeration plants (with power provided, if required) and underground spot cooling solutions.

“Newer mines are also continuing to come online in Australia and around the world,” Bevan said. “We are supplying modular cooling solutions throughout the entire mining lifecycle.

“We are constantly looking for opportunities to improve on our strengths to assist our clients further into the future. We provide flexible energy solutions and services to the mining sector and provide high standards regardless of a mine’s location in the world.”

PYBAR sets records at Glencore’s Black Rock mine with Sandvik DL432i longhole drill

The introduction of PYBAR’s new Sandvik DL432i longhole drill in October 2020 has led to month-on-month improvements in drilling productivity at the Black Rock copper-lead-zinc mine, in Queensland, Australia.

Versatile and compact, the Sandvik DL432i is a fully mechanised electro-hydraulic top hammer longhole drill, designed for large-scale mining. The Sandvik iSOLO drilling control system allows the client (Glencore in this case) to provide electronic drill plans on a USB, which is plugged straight into the drill. The operator then lines the drill up on the survey markings and selects the required drill design, with the remainder of the drilling taken care of by the iSOLO software.

Since arriving on site, a specialised pump has been installed on the DL432i, allowing AMC (a subsidiary of IMDEX) to add a Bore Hole Stabiliser™ to the water circuit while drilling to improve hole integrity in the soft ground conditions. This technology, combined with Sandvik’s iSOLO drilling control software, has been key to PYBAR’s production success at Black Rock to date, the contractor said.

“The ground conditions at Black Rock have put Sandvik’s iSOLO drilling control system to the test, and the technology has proven itself with flying colours,” PYBAR said. “After several months of on-site refinement of the automated drilling system, the drill can now operate with minimal operator input.”

This has led to month-on-month increases in production drilling rates with a record month in March, closely matched in April, according to PYBAR. This, in turn, has meant a significant increase in available production fronts resulting in increased tonnes and improved overall project performance.

Trials of automated drilling for complete firing patterns will begin shortly at Black Rock to enable drilling to take place during firing and shift change, as well as free up the operator to assist with other tasks around the mine, PYBAR said.

The transition to further automation has the potential to significantly maximise both productive drilling time and overall performance for the project, it added.

SENET wins EPCM gig at AMAK’s Moyeath copper-zinc project in Saudi Arabia

Al Masane Al Kobra Mining Co (AMAK) has awarded SENET, a wholly owned subsidiary of DRA Global, the engineering, procurement and construction management (EPCM) contract for the design and execution of the Moyeath copper-zinc project in the Kingdom of Saudi Arabia, SENET says.

AMAK has been producing copper, zinc in concentrate and gold and silver in doré from its operations in the country since 2012.

Moyeath is a third major orebody (together with Saadah and Al Houra) discovered in the immediate vicinity to the AMAK underground mines. The Moyeath orebody is a high-grade copper-zinc volcanogenic massive sulphide deposit, SENET says.

The planned 400,000 t/y run of mine flotation process plant will produce copper and zinc concentrates, while filtered tailings will be trucked to an existing dry stacking area operated by AMAK, which handles tailings from its Al Masane (pictured) and Guyan process plants.

Preliminary test works shows it is possible to produce saleable copper and zinc concentrates, with most of the gold and silver reporting to flotation concentrates, SENET noted. The mineralogy of the Moyeath orebody is complex and requires a similarly complex approach to produce copper and zinc concentrates at favourable recoveries and saleable concentrate grades.