Tag Archives: XRT

TOMRA XRT ore sorters providing Mt Carbine with tungsten upgrade, circular economy advantages

TOMRA X-Ray Transmission (XRT) sorters are providing a game-changing solution for the EQ Resources-owned Mt Carbine mine in Queensland, Australia, reducing costs and achieving high-purity tungsten ore for follow-on processing while contributing to a circular economy by producing green aggregates for sale, the ore sorting company says.

The Mt Carbine mine, northwest of Cairns, Queensland, was acquired by EQ Resources in 2019. The company entered a joint venture with Cronimet Group to set up tungsten extraction from the mine’s large waste dump and tailings. It is also planning to operate the open pit and underground mine, of which it has full ownership.

EQ Resources management has a long-standing relationship with TOMRA, having used its sorters with success on a variety of projects since 2011, TOMRA says. Based on this experience, the company turned to TOMRA once again for the Mt Carbine mine, with test work conducted at TOMRA’s Test Center in Wedel, Germany, confirming its XRT technology would provide the solution for the project.

“We were confident it would work, but we sent a small sample for testing to make sure,” Kevin MacNeill, CEO of Mt Carbine mine, EQ Resources, said. “The advantage of TOMRA’s sorters compared to others is in the image resolution: it is able to resolve the finer inclusions in the tungsten. This high resolution gives us better recovery and more control over the sorting process.”

Mt Carbine is currently mining the 12 Mt of low-grade historical stockpiles. The ore is crushed and screened at 6 mm and 40 mm. Two TOMRA XRT sorters are used to pre-concentrate the feed in the 6-40-mm-size range before processing in the wet plant. Approximately 10% of the sorters’ feed mass is ejected as product with a recovery of tungsten of well over 90%. This means only 10% of the mass is processed in the wet plant, dramatically cutting running costs, reducing the required size of the wet plant, as well as saving water and energy, TOMRA says.

“We let the technology do the work for us and take out all the rubbish and we’re left with just the pure tungsten to send to the processing plant – and we do that very cheaply using the sorters,” MacNeill says. “One of the best things about the TOMRA XRT is the cost savings to the operation. It costs approximately A$1.5/t ($1.02/t) to sort and then it costs A$14/t for wet processing: as we take out 90% of the sortable fraction mass, we only have to process 10% of the higher grade concentrate and natural -6 mm material while maintaining recovery, so our cost benefit is obvious.

“We couldn’t afford to run this waste dump if we had to crush everything to 6mm and process it through the wet plant, it would be too low grade and costly.”

EQ Resources is also taking advantage of the TOMRA XRT sorters to create an additional revenue stream from the waste material.

MacNeil explained: “Normally you would grind the waste down to 6 mm and put it through the jigs, but, by putting it through the TOMRA sorters, we are able to keep a whole range of aggregates on the coarser size fractions. The sorters remove any material containing acid-forming sulphides and the waste rock that comes out is incredibly clean. We are, therefore, able to use it in making all kinds of different quarry products – from road bases to concrete aggregates. It’s a perfect example of a circular economy.”

“Selling these green aggregates adds a significant portion to our business – about A$5 million a year – and that’s all because of the TOMRA sorters. In fact, we’ve probably paid for each machine from this revenue five times over.”

The TOMRA XRT sorters are delivering both environmental and business benefits to the Mt Carbine operation, to the satisfaction of MacNeill: “They’re dry, they create no water usage, they require very little power compared to what we use in the processing plant, so it’s a real advantage to us to have these, and we’re looking at purchasing a third one in the near future.

“From an environmental point of view, I think the TOMRA sorters will play a huge role in the future because of their capability of removing sulphides. If you remove sulphide before stockpiling waste rock, you will have the benefit of no acid creation and drainage – and it would reduce your footprint in your closure plans.”

TOMRA Mining to demonstrate Final Recovery diamond sorter at Electra Mining 2022

TOMRA Mining will showcase its sensor-based sorting solutions at the Electra Mining 2022 exhibition, in Johannesburg, South Africa, in September, showcasing, for the first time, live demonstrations of its COM XRT 300 /FR Final Recovery sorter for diamond operations.

Representatives from its Sales and Field Service teams will also present TOMRA’s offering of advanced digital products and services, such as the TOMRA Insight cloud-based platform and its latest generation TOMRA ACT PC-based system, as well as its portfolio of sorting solutions for the diamonds, metals and industrial minerals industry at the show, which runs from September 5-9.

Corné de Jager, Diamond Segment Manager TOMRA Mining, said: “The Electra Mining Show is the perfect platform for us to showcase TOMRA’s advanced mining solutions. This important exhibition attracts a wide audience – from operators and metallurgists – interested in smart solutions that are simple to operate and maintain, to decision makers who need to be up to date with the latest value-adding technologies. At the event we will have the opportunity to meet them face-to-face and discuss their requirements, giving them a taste or TOMRA’s collaborative approach, product expertise and after-sales support.”

TOMRA will demonstrate the Final Recovery sorter with fine kimberlitic or alluvial ore together with diamond powdered tracers in a Final Recovery and Sort House application. Visitors will be able to experience first-hand the sorter’s capability to produce an ultra-high diamond-by-weight concentrate with an exceptionally low yield by using TOMRA’s proprietary ultra-high-resolution sensor, advanced new image processing and high-precision ejector valve system, the company says. The sorter offers 100% diamond detection within the specified size fraction and > 99% guaranteed diamond recovery with appropriate feed material preparation.

“We are very excited to demonstrate the TOMRA COM XRT 300 /FR sorter,” de Jager says. “It completes our unique partnered diamond recovery ecosystem, which covers the entire process. We are now able to offer our customers a full XRT solution to sort +2-100 mm particles: +4-100 mm particles with our bulk concentration sorters, and +2-32 mm particles with the COM XRT 300 /FR in its Final Recovery, Sort House or small-capacity exploration applications. The sorter offers higher efficiency, better grade, simplified security requirements with fewer sorting stages and a smaller footprint. It reduces complexity and operational costs, and unlocks the potential for previously deemed non-profitable projects and marginal deposits to be economically viable. ”

The COM XRT 300 /FR sorter can also add value to existing kimberlitic and alluvial operations that use conventional bulk-concentration methods like rotary pans, dense medium separation or X-ray luminescence, if installed in a Final Recovery and/or Sort House function after these existing processes. With a contained capital expense, operations can benefit from a quick, simple and significant revenue gain, TOMRA says.

The TOMRA team at the exhibition will explain the full benefits of its complete partnered diamond recovery ecosystem consisting of XRT technology covering the entire process – from Bulk Concentration to Final Recovery and Sort House applications – as well as its advanced digital products and services. These include the newly refreshed TOMRA ACT PC-based system interface and TOMRA Insight cloud-based subscription solution.

TOMRA Mining has 190 sorter installations operating around the world, of which more than 60 are in Africa. It offers installation opportunities in Africa in the metals industry, for example in applications such as lithium, chromite, platinum, manganese and gold.

Tungsten West breaks ground at Hemerdon for TOMRA XRT ore sorters

Tungsten West says it has broken ground at its Hemerdon tungsten-tin mine in Devon, England, with the first sod turned for the installation of the TOMRA X-ray Transmission (XRT) sensor-based ore sorters.

This event, the company says, marks another major step in the company’s upgrade and refurbishment plans for the project’s processing plant.

Hemerdon is, Tungsten West says, the third largest tungsten resource globally, as well as being a previously producing mine that was operational from 2015-2018. Tungsten West purchased the Hemerdon Mine in 2019, and has since completed a bankable feasibility study that demonstrated an extensive reserve of approximately 63.3 Mt at 0.18% W and 0.03% Sn, as well as 37.4 Mt of saleable aggregate material. The company estimates that the life of mine is currently 18.5 years with the opportunity to extend this through future investment.

As announced earlier this month, the company took receipt of important long-lead equipment items, including the seven XRT ore sorters, which will make up part of the upgraded equipment the company plans to install into the front end of the processing plant. The XRT ore sorter will substantially improve and streamline operations once production restarts, minimising plant downtime, increasing recovery as well as a host of ESG benefits, it said.

After significant test work, Tungsten West engaged TOMRA to supply the seven units that are required to treat the run of mine throughput. This consists of six duty units and one standby unit. Orders and deposits for these units were placed in 2021 and the units have now been delivered to the UK and await final transfer to Hemerdon where they will be installed in the front end of the processing plant.

Additionally, the company is pleased to announce the appointment of James McFarlane as Managing Director of Tungsten West. McFarlane previously held the position of Technical & Operations Director of the company.

Max Denning, Tungsten West CEO, said: “We are extremely excited to have broken ground at Hemerdon this week, marking an important milestone in the project’s restart. Ensuring the UK and the western hemisphere have got access to two key critical minerals has never been more profound. We are also delighted to announce James as our new Managing Director; his extensive experience will prove invaluable in the company’s development as we move closer to first production at Hemerdon.”

TOMRA continues to build ore sorting Insight across mining space

Some 18 months after launching TOMRA Insight to mining customers, the cloud-based data platform is making inroads across the North American mining sector, Harold Cline and Jordan Rutledge told IM on the side lines of the MINEXCHANGE 2022 SME Annual Conference & Expo in Salt Lake City recently.

TOMRA rolled out the subscription-based service to mining back in late 2020, with one of the early adopters being the Black chrome mine in South Africa, one of two mining projects that form the basis of the Sail Group’s plans for long-term sustainable chrome production.

TOMRA Insight, the company says, enables sorting machine users to improve operational efficiencies through a service that turns these machines into connected devices for the generation of valuable process data.

Cline and Rutledge, both TOMRA Sorting Area Sales Managers for North America, said numerous customers were now taking advantage of TOMRA Insight across the region, with many more interested in leveraging the continuous data streams coming off a web-based portal stored securely in the cloud.

TOMRA’s Harold Cline & Jordan Rutledge

“This is seeing mine managers able to tap into how operations are performing today, while tracking that against performance over the last day, week, month, quarter, etc,” Cline told IM. “With the help of our support network, these operations are able to achieve more consistent performance.”

With more customers signing up to TOMRA Insight and more data being generated, the pair were confident future iterations of the platform would be able to offer machine-learning algorithms that helped, for example, predict failures or highlight potential areas for operational improvements.

At the show, the pair were also highlighting the ongoing demand for TOMRA’s Final Recovery sorter, the COM XRT 300/FR, which, since launch, has been successfully deployed at the Letšeng diamond mine in Lesotho, owned by Gem Diamonds. The solution has gone on to be rolled out at other operations.

The introduction of the COM XRT 300/FR, TOMRA became the first company in the industry able to supply a full diamond recovery solution using XRT technology from 2-100 mm, with the unit delivering concentration factors of up to one million with limited stages and guaranteeing more than 99% diamond recovery, according to the company.

Outside of diamonds and sorter analytics, Cline was keen to talk up demand from the gold sector for the company’s sorters.

One of the key differentiators of its offering to the yellow metal space is the ability to scan the material with a multi-channel laser sensor. In an ore sorting setup that involves both XRT and LASER sensor-based machines, the TOMRA solution can remove particles containing sulphide minerals using XRT and subsequently leverage laser sensors to remove particles containing quartz and calcite.

TOMRA says its segregated option can potentially improve recoveries in quartz-associated gold applications thanks to a laser chute-based machine that analyses rocks from both sides. Other belt-based laser machines can only analyse a maximum of 40% of the rock’s surface, according to TOMRA.

“In the gold scenario, we are using XRT to sense and sort with sulphide minerals as a proxy,” Cline said. “At the same time, our laser scanner allows further separation capabilities through identification of minerals such as quartz and calcite.”

Vista Gold, which is developing the Mt Todd project in Australia, anticipates that this combined solution could eliminate approximately 10% of the run-of-mine feed to the grinding circuit, allowing the company to decrease the grind size and thereby increase recovery of the contained gold.

The COM XRT 300/FR offers a full diamond recovery solution

Cline added: “In North America, we have three projects in the gold space we’re working on at the moment that appreciate our unit’s ability to analyse the whole of the particle through our chute mechanism, as opposed to conveyor-based systems that can only analyse one angle of the particle.”

While TOMRA offers multiple sensors on its units through its modular platform, Rutledge said the company continues to have discussions on combining its solutions with other bulk sorting suppliers to further improve the process, naming prompt gamma neutron activation analysis (PGNAA) technology as one specific area of interest.

“We very often refer clients on to other companies when our solution may not match their brief,” she said. “At the same time, we have done some flowsheet work to include our solution with others currently on the market and believe it is only a matter of time before a combination of the two comes into a flowsheet.”

TOMRA’s XRT solution creates value from waste at Mina Esperanza de Caravelí in Peru

The integration of TOMRA’s ore sorting technology at the Mina Esperanza de Caravelí mine in Peru has helped the polymetallic miner produce more metal as well as clean up its legacy tailing operations.

The close collaboration between two companies emphasises a shared philosophy, that of making the most of natural resources and embracing a circular economy.

Mina Esperanza de Caravelí, owned by MTP and operated by Minera Croacia, is a polymetallic vein deposit with a mining rate of 150 t/d. It is located in the district of Atico, in the Nazca-Ocoña geological gold belt in the southern part of Peru, and contains narrow veins with a rosary formation, of which over 30 have been discovered so far. The mineralisation is located in vein fill fractures of hydrothermal origin and are mesothermal in appearance.

In 2019, Minera Croacia contacted TOMRA to explore a solution to extract value from low-grade material previously deemed uneconomical, and to address the environmental issue of metals left in the dumps.

Marco Fernandez Concha, Senior Geologist to Minera Croacia, said: “Mining operations need to find ways to optimise the use of natural resources while reducing waste and their impact on the environment as much as possible. With TOMRA’s ore sorting technologies, this is possible.”

A sensor-based ore sorter represents a significant investment for a mine the size of Minera Croacia, according to Emilio Uribe, Senior Metallurgical Advisor at Minera Croacia.

“When we purchase important equipment, we need to analyse the solution in great detail because we can’t afford to make mistakes,” he said. “We need it to work and deliver the results we want from the start. TOMRA has adapted to our needs as a small business with limited resources. They have been an important advisor, giving us all the support we needed with highly qualified and knowledgeable staff. They have really committed to the project and found the solution that meets our operational needs and is financially viable for us.”

The teams from TOMRA and Minera Croacia worked closely to precisely analyse the requirements and identify the best solution. TOMRA’s Test Center in Wedel, Germany, conducted three series of tests on samples from the mine to narrow down the requirements. A technical team from Minera Croacia attended the final session, which gave them a better understanding of what TOMRA’s XRT technology could do for their operation.

Christian Korsten, who at the time was the Test Center’s Manager, said: “This project stands out for presenting different types of ores from different locations. Usually we test one or two different ores for a customer, but, with Minera Croacia, we had different metallogenic veins. They were all a little bit different in mineralogy, sensor response and in the customer’s objectives for each.”

Strong communication between the two companies’ teams was crucial to the successful outcome – especially since COVID-19 travel restrictions limited the opportunities for face-to-face meetings.

Mathilde Robben, TOMRA Key Account Manager, said the company ensured Minera Croacia received the support and advice they needed throughout the process.

“We did it all through online meetings,” she said. “The management team and staff at Minera Croacia were always to the point and friendly, and together we completed this fast-track project.”

Korsten agreed: “Minera Croacia had very clear objectives. All our questions were answered in a perfect, fast and professional manner, and the same applies to the discussion of the test results. This project was one of my favourites in almost 10 years in the Test Center.”

Following the detailed analysis of the test results and Minera Croacia’s requirements, Robben proposed the use of a TOMRA COM Tertiary XRT sorter as the solution: a machine suited to the particle size range of the dump material (-25 mm/+ 10 mm and -40 mm/+ 25 mm) and an investment that fitted Minera Croacia’s budget.

The test results made a clear business case for the sorter, showing that out of 1,300 t of run of mine material containing gold and copper, 21% are fines (-10 mm) and screened out. This results into a concentration of gold and copper in the fines and, therefore, this material does not need to be sorted. Of the rest of the material, 34% is enriched, going from a grade of 2.7 g/t gold-equivalent to 5.12 g/t gold-equivalent – almost double.

This leaves 45% of the material discarded as waste with very low metal content, 0.41 g/t gold-equivalent, which addresses the environmental issue, as it contains virtually no contaminants. This also shows that maximum value has been extracted from the material, as there is virtually no gold left, TOMRA said.

Uribe said: “The test has shown that TOMRA’s sorter can create value from material that would have gone to the waste dump, from 33% of the run of mine that is too low-grade for processing to be financially viable.”

The TOMRA COM Tertiary XRT sorter is now installed and has been operating since December 2021 re-processing the mine’s 800,000 t of historic dumps. It is delivering on all counts for Minera Croacia: now able to increase the grade of the dump material that was not considered economic, it has reduced freight costs of the operation as it is now transporting less low-grade material to its processing plant, and it has successfully addressed the environmental impact of its waste materials.

Uribe concluded: “All the calculations we made when we evaluated this investment are being fulfilled. The sorter’s performance is perfectly consistent with the test results, and we expect it to pay for itself as planned within two years – including the other components and infrastructure of the circuit.”

The company’s management is so impressed with the results achieved that it is considering investing in further sorters for low grade run of mine ore with the aim of extracting value from mineral that is currently considered marginal, according to TOMRA.

Australian Government backs EQ Resources Mt Carbine ore sorting plan

EQ Resources Ltd says it has successfully secured A$600,000 ($422,386) in co-investment from the Australian Federal Government’s Advanced Manufacturing Growth Centre (AMGC) via the A$30 million Commercialisation Fund. Combined investment from EQ Resources, its partners and AMGC, totalling A$1.97 million, will assist in commercialising industrial-scale operations for advanced minerals processing flowsheet developed for the Mt Carbine Expansion Project, in Queensland, EQ said.

Technologies to be incorporated include the advanced X-ray Transmission ore sorting technology from TOMRA Sorting Pty Ltd, as well as hyperspectral imaging sensors developed by Plotlogic Pty Ltd. The implementation will further be supported by Cronimet Australia Pty Ltd and The University of Queensland – Sustainable Minerals Institute, it said.

The formal co-funding agreement between AMGC and the company has been finalised and signed.

AMGC is an industry-led, not-for-profit organisation established through the Australian Government’s Industry Growth Centres Initiative. AMGC’s vision is to transform Australian manufacturing to become an internationally competitive, dynamic, and thriving industry with advanced capabilities and skills at its core.

AMGC’s Managing Director, Dr Jens Goennemann, said: “EQ Resources’ project brings together industry and research leaders to commercialise a world-leading technology which will convert what was once a mining waste product into new revenue streams. The project proves that Australia’s manufacturing industry is stepping forward to develop globally relevant solutions which will improve operations and add value in the process.”

EQ Resources, as a result of the acquisition of Mt Carbine Quarries in June 2019, now has 100% ownership of the two mining leases and surrounding exploration projects at the project. In a joint venture with Cronimet, the tungsten processing plant has been refurbished, commissioned and expanded to 300,000 t/y capacity. The installation of the pilot sensor-based sorting technology has seen a 20-plus times upgrade of feedstock grade, the company says.

The company is in the process of completing the required environmental amendments to allow the operation to process 300,000 t/y and eventually 1 Mt/y. Once the bulk test work is completed, a feasibility study will be completed for the design of the 1 Mt/y operation.

TOMRA Mining’s ore sorting solution helps Renison tin mine do ‘more with less’

TOMRA Mining and its X-ray Transmission (XRT) technology has, the company says, provided an effective solution for the extreme conditions at the Bluestone Mines Tasmania JV (BMTJV) Renison tin mine in Tasmania, Australia, with sensor-based ore sorting solution unlocking significant value and delivering environmental benefits.

The Renison mine is 50% owned by Metals X through the BMTJV, and is the only major tin mine in production in Australia with a mining rate of close to 1 Mt/y, according to TOMRA. While slated capacity is 1 Mt/y, the concentrator is restricted to 750,000 t/y.

The mine’s extreme humidity and highly acidic processing water (pH around 4.5) create unique challenges for the sorting process, the equipment and waste management, according to TOMRA.

A complex flowsheet

The underground mine operates a primary crushing system before the material is transported to the surface through a shaft. Once there, it enters the pre-concentration plant, where it undergoes a three-stage crushing, screening and cleaning process. The particles are split into two fractions – 10-25 mm and 25-60 mm – which are fed into two TOMRA XRT sorters. The output consists of two streams: the product, which is transferred to the wet plant, and the waste, which is fed into a TOMRA EM sorter to separate acid-forming sulphides from this waste stream.

In the wet plant, the product goes through primary grinding followed by bulk sulphide flotation. The tailings are processed downstream to concentrate the cassiterite tin mineral through gravity concentration; gravity tails are further treated via desliming and tin flotation. The combined concentrates are fed to a leaching circuit to remove carbonate minerals. After a final wash stage, the concentrate is de-watered and dispatched.

BMTJV approached TOMRA to address two key requirements at the plant. The first was the need to upgrade the tin feed to the plant, as Ben Wraith, Principal Project Metallurgist at BMTJV (pictured below), explained: “The Renison tin operation wanted to achieve economies of scale, putting more tonnes through the front end of the plant without upgrading the back end downstream – we wanted to do more with less.”

The second requirement was to address the environmental issue of removing acid-forming sulphides from the waste.

Following site visits and extensive discussions with BMTJV’s teams, TOMRA proposed a solution that addressed the tin feed quality with two COM Tertiary XRT 1200 sorters and the waste issue with a COM Tertiary EM 1200 sorter. A team from BMTJV visited the TOMRA Test Center in Sydney, Australia, where they observed what the XRT sorter operating at capacity is capable of.

Gavin Rech, Technical Manager at TOMRA, said: “Our XRT stands out for the high spatial and density resolution and its ability to do contrast sorting, identifying fine high-density tin inclusions in the ore with an accuracy that has no equal on the market. On top of that, it can separate it from the acid-forming sulphides, so that we have the ability of pulling the tin into the first product and sending the rest to the EM sorter.”

Gavin Rech, Technical Manager at TOMRA

The two COM Tertiary XRT 1200 sorters went into operation in 2018. Initially, BMTJV’s strategy focused on low reject grades, devoting less focus to achieving the mass reject rate and overall process plant throughput. However, the specific conditions at the Renison mine affected the results achieved. The large variance in run of mine (ROM) particle size distribution resulted in insufficient stability in the feed to the circuit. In addition, the extremely wet conditions in west Tasmania and consequent high ambient moisture content, combined with the high moisture of the ore delivered from underground, further affected the sorting process.

In 2019, a new investigation was conducted into the ore sorting performance and led to a change of direction, where the operation shifted away from targeting low reject grades, towards sorting as aggressively as possible, according to Wraith, moving from a “tin recovery-based” operating strategy to a “mass reduction” one.

“We are getting 20-25% mass reduction, so 75-80% of the materials are going into the wet plant, and we are still achieving 97-98% tin recovery overall across the crushing circuit,” he said. “Pre-concentration didn’t materially impact overall recovery because the tin in the material that is rejected as waste is extremely fine grained and a proportion is associated with sulphides, so it wouldn’t have been fully recovered in the downstream wet plant and would have been lost to tailings.”

This approach, he said, is best for Bluestone’s application as it provides the ability to process 15-20% more tin units without having to upgrade the downstream concentrator.

Wraith added: “Operating the sorting circuit has slightly increased our overall processing cost, but this is more than offset by the large increase in ROM throughput by 15-20% and, thus, tin production, so the unit cost per tonne of tin produced is reduced by almost 10%. We’ve broken multiple production records in the last year in tin units, and this gives us confidence in what we can achieve because the machine performs over and over again if you treat it right and if you prepare your feed correctly.”

TOMRA XRT success leads to upgrade decision

In view of the results achieved with the two TOMRA XRT sorters, BMTJV decided to upgrade the ore sorting circuit with two new, recently launched XRT models with stainless steel internal parts and advanced features such as the TOMRA ACT user interface and the TOMRA Insight cloud-based platform, according to TOMRA.

“The decision to buy new machines was easy,” Wraith said. “The stainless steel will assist prolonging the TOMRA sorter’s life by protecting the unit from our high-moisture and corrosive environment. The more ergonomic design will help our maintenance teams, which is particularly important for machinery operating in these harsh conditions.”

Wraith said the use of TOMRA Insight, the ore sorting company’s subscription-based service that relays and analyses machine data, will “enhance everybody’s understanding and experience of the machines”.

He added: “It will be more of an analytical platform for our metallurgy and maintenance staff, providing ample opportunity to gain valuable information that can be analysed and optimised over time. The one feature I am personally interested in is the particle size monitoring through the machines, which will enhance our overall circuit performance because we have an integrated circuit with the crushing and screening plant. Feed preparation is key to maintain a consistent performance – knowing how well you’re preparing your feed in a live fashion can only end up with a better result.”

TOMRA will also be able to log into the machine and check the daily reports generated by TOMRA Insight, so its technical teams will be prepared ahead of site visits for maintenance or optimisation.

Wraith concluded: “TOMRA has been working with the site maintenance team to tailor solutions to our operating environment, which has been invaluable. TOMRA supported me through site visits, which included equipment inspections, site-based training of our personnel, and an openness to continually improving the technology and finetune it to our site-specific requirements. They assisted the site with troubleshooting, optimisation, discussing the nuts and bolts of the issues as they arose, and finding a solution that works.”

Kutcho Copper outlines combined open-pit/underground plan for mine

Kutcho Copper Corp has outlined a plan to develop an open pit and underground operation at its copper and zinc project in northern British Columbia, Canada, with the publication of a feasibility study.

The results of the study highlight an 11-year mine life with metal production of 533 Mlb (241,765 t) of copper, 841 Mlb of zinc, 10.6 Moz of silver and 129,700 oz of gold at all-in sustaining costs of $1.80/lb ($3,969/t) of copper equivalent. It came with an initial capital cost of C$483 million ($388 million).

The Main deposit at Kutcho is designed to be mined primarily as a conventional shovel and truck open-pit operation, with a deeper remnant mined by underground longitudinal longhole open stoping (LLHOS) with cemented rock fill (CRF). The underground Esso deposit is also designed to be mined using LLHOS with CRF.

A total of 17.3 Mt is planned to be mined over an 11-year mine life, with 14.5 Mt coming from the open pit and 2.8 Mt from the underground mines. A steady-state crusher production rate of 4,500 t/d is expected be achieved by the end of the first year of operations.

After primary crushing at an average steady state rate of 4,500 t/d, an ore sorter using an X-ray Transmission (XRT) sensor would remove low-grade and waste material from the feed to the SAG and ball mills, followed by conventional flotation, regrind and dewatering circuits. Approximately 3,900 t/d of ore would report to the milling and flotation circuit after ore sorting. The XRT plan follows testing of Kutcho samples at TOMRA Sorting Mining facilities.

The project design includes an extensive progressive reclamation program, including the backfilling of the open pit and water treatment during operations and for the closure period.

The company also plans to use liquified natural gas for power generation as opposed to diesel, which will significantly reduce the generation of greenhouse gases and reducing the potential for fuel spills. This would see four 2.5 MW LNG generators plus one on standby used, with a 2 MW diesel generator providing occasional plant start-up assistance.

Vince Sorace, President & CEO of Kutcho Copper, said: “The feasibility study represents a major milestone for Kutcho Copper as we continue to advance the high-grade Kutcho copper-zinc project towards a development decision. The significant redesign and engineering of the project delivers a mine plan that is a predominantly open-pit mining operation with the concurrent development of two underground mines. The mine plan has resulted in a technically robust and capital efficient project with a minimised footprint.

“The results of the feasibility study highlight the attractive economics of the Kutcho project which are resilient at lower metal prices, very attractive at base case prices and exhibit significant leverage to rising prices as reflected in spot metal prices with a C$931 million after-tax NPV (7% discount) and a 41% internal rate of return. We believe that the results of the feasibility study mean that Kutcho Copper is now one of the most undervalued copper investment opportunities in North America.”

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.