Tag Archives: x-ray transmission

Wescoal after RoM upgrade with Acrux, IMS Engineering XRT ore sorting solution

Acrux Sorting Technology has announced that its advanced sensor-based sorting technology is to be deployed at a Wescoal Holdings Ltd-owned coal mining operation in South Africa.

Acrux subsidiary, Acrux Sorting Coal (ASC), has signed a coal beneficiation agreement with two wholly owned subsidiaries of Wescoal, whereby ASC will deploy advanced sensor-based sorting technology to upgrade lower-grade coal from the mines.

Under the agreement, ASC will provide a fully funded turnkey crushing, screening and sensor-based sorting solution centred around advance dual-energy X-ray Transmission (XRT) unit to process run of mine (RoM) coal.

The plant is to be designed, constructed, commissioned, operated and maintained by IMS Engineering Limited, Acrux’s partner on such ore sorting projects. IMS Engineering is a subsidiary of Germany-based HAZEMAG & EPR GmbH.

ASC’s sorting solution offers significant economic benefits as coal resources can now be upgraded to be included as a saleable product, which will reposition the mines along the cost curve, it said.

Paul Bracher, Managing Director of IMS, said: “The XRT technology has proven its ability to upgrade RoM coal through rejecting material that has sulphur or ash content that exceeds programmed parameters.”

The solution will also have a positive environmental impact as no water is used during beneficiation, and the carbon footprint is reduced through the optimisation of transportation and materials handling.

Wescoal’s Executive Director, Thivha Tshithavhane, said: “This sorting technology solution will enable us to impact on ESG, while creating shareholder value from optimising our coal resources at no capital investment.”

Sean Browne, ASC’s Chairman and Group Founder, added: “Partnering with Wescoal underlines our commitment to driving sustainable innovations that reduce the environmental impact of mining.”

TOMRA boosts sensor-based ore sorting process with key updates

TOMRA Sorting Mining has introduced the TOMRA ACT user interface together with a new image processing pipeline and additional process data for TOMRA Insight, all of which will, the company says, enable improvements in the overall sorting process for greater productivity and profitability.

The new TOMRA ACT graphical user interface (UI) brings a fundamental change in the way customers interact with their machines, making it easy to control the work flow in their sorting process with simple, intuitive touch gestures and actions on the screen, according to the company.

The UI provides sorting information and real-time process data at a glance through easy-to-understand graphics. With this clear information, the operator can better monitor the sorting process and make fast adjustments at any time, the company claims. The quick feedback on machine performance and throughput enables them to optimise the process, maximising productivity and efficiency.

Ines Hartwig, TOMRA Product Manager

Ines Hartwig, TOMRA Product Manager, explained: “Throughout the development process of TOMRA ACT, we conducted many in-depth discussions with our customers to ensure we provided them with an interface that would improve the performance of their sorters, benefitting their business. We have been testing it with customers and the feedback has been very positive; in particular about the ease of use, even remotely, which facilitates controlling the process and adjusting settings.

“With the new interface, customers interact with their sorters in a much more intuitive way and they have better guidance on how to improve the overall handling of the sorters. As a result, they will be able to improve the productivity of their sorting plant and the profitability of their mining operation.”

TOMRA is introducing the new UI on all its current X-ray Transmission (XRT) sorters and is planning to extend it to other machines in its offering at a later stage. Upgrade packages to retrofit previous models of its XRT sorters will also become available.

The new Image Processing Pipeline, meanwhile, analyses the data sent by the sorter’s sensors and cameras. This solution provides TOMRA with even more flexibility to adjust and customise the image calculations according to the application and the customer’s specific requirements to achieve the best possible sorting results.

The enhanced image processing solution also collects detailed process data, such as information on particle size distribution of the feed, belt occupancy for insights on feed tonnages, or data relating to the health of the sorter. All these statistics are fed to TOMRA Insight, the cloud-based data platform, adding to the process information it has already received. TOMRA said: “This enables customers to improve the overall sorting process further, taking fast action when changes occur in upstream equipment or in the material’s composition. They are able to better monitor and control their processes, the feed material and the sorted fractions, improving their profitability.”

The new enhanced Image Processing Pipeline, and additional data fed to TOMRA Insight, have already been introduced on TOMRA XRT sorters and will in the future be extended to other products.

Peel Mining’s South Cobar preliminary flowsheet to factor in ore sorting

Peel Mining says positive results from ore sorting test work at the Southern Nights and Mallee Bull deposits, part of its 100%-owned South Cobar Project, in western New South Wales, Australia, provide encouragement for the inclusion of this pre-concentration technology into future process plant design.

So encouraged by this testing is Peel that it has engaged GR Engineering to integrate ore sorting technology into an updated processing plant technical report for the project.

At the same time as this, Peel announced that GR Engineering had recently completed a preliminary process plant technical report for South Cobar that considers crushing, grinding, gravity, flotation and cyanidation process stages for the recovery of gold, silver, copper, lead and zinc from the various mineralisation styles within Peel’s deposits.

Meanwhile, the recently received positive preliminary ore sorting test work results from work undertaken on diamond drilling samples shows there is potential for improvements in the flowsheet.

The ore sorting test work, completed in conjunction with ongoing metallurgical studies, was undertaken by Steinert and TOMRA.

Steinert ’s test work on Southern Nights mineralisation demonstrated strong recovery and upgrade potential with two size range samples returning, on average, circa-93% Zn, circa-91% Pb, circa-91% Ag, circa-87% Cu and circa-82% Au recoveries to an average of circa-54% of the feed mass (circa-46% of feed mass rejection) increasing the lead and zinc grades by 61% and 64%, respectively.

TOMRA’s test work on Mallee Bull mineralisation achieved significant waste mass reductions while maintaining very high copper recoveries (≥95% for the higher-grade breccia copper and massive sulphide copper samples), the company said. A lower grade breccia copper sample upgraded from 0.59% Cu to 1.05% Cu with 77% Cu recovery and 56% mass rejection, it noted.

“Positive results from ore sorting at Southern Nights and Mallee Bull deposits provide encouragement for the inclusion of this pre-concentration technology into future process plant design and, as a result, Peel has engaged GR Engineering to integrate ore sorting technology into an updated processing plant technical report,” the company said.

Peel’s Executive Director of Mining, Jim Simpson, said: “The completion of the processing plant technical report by mineral processing solutions experts GR Engineering is a critical first step in understanding the potential composition of the milling infrastructure required for the company’s development plans.

“The detail presented in the report by GR is impressive and the report will form the basis for ongoing preliminary studies for the refinement and improvement of the processing plant design as new information comes to hand.

“We are also very pleased with the potential of ore sorting as part of any future South Cobar project hub’s processing route with initial test work pointing to the amenability of both Southern Nights and Mallee Bull mineralisation to separation using 3D-XRT ore-sorting technology, allowing for the simultaneous rejection of barren or waste material whilst retaining the bulk of contained metal, and in the process, upgrading the value of the ore.”

Simpson added: “Apart from reducing the overall feed mass by the rejection of waste at early stage, other benefits of ore sorting include potentially upgrading lower-grade mineralisation and reducing the size of the processing plant offering potentially reduced capital, power, water and tailings storage needs.”

TOMRA XRT units help recover unbroken 998 ct diamond at Lucara’s Karowe mine

TOMRA’s COM XRT 2.0/1200 ore sorters have aided Lucara Diamond’s Karowe diamond operations, in Botswana, once again, recovering an unbroken 998 ct high white clivage diamond from the 100%-owned mine.

The diamond, measuring 67 x 49 x 45 mm, was recovered from direct milling of ore sourced from the EM/PK(S) unit of the South Lobe, and follows a series of significant diamond recoveries during this recent production run, including several top quality clivage and gem-quality stones of 273 ct, 105 ct, 83 ct, 73 ct, and 69 ct in weight.

“The EM/PK(S) forms an important economic driver for the proposed underground mine at Karowe and continues to produce large gem-quality diamonds in line with expectations, a further testament to the strong resource performance at Karowe,” the company said.

Last year, a feasibility study showed the company could double the mine life of Karowe by establishing an underground mine for $514 million in pre-production capital.

The 998 ct diamond (pictured) was recovered in the MDR (Mega Diamond Recovery) XRT circuit that allows for diamond recovery post primary crushing and prior to milling. The MDR circuit has, in the past, treated material in the size range between 50-120 mm. This latest recovery represents the second plus-500 ct diamond recovered from this circuit in 2020, Lucara noted.

Year to date, Karowe has produced 31 diamonds greater than 100 ct, including 10 diamonds greater than 200 ct comprising of the 549 ct Sethunya, and the 998 ct diamond.

Eira Thomas, Lucara CEO, said: “Lucara is extremely pleased with the continued recovery of large high-quality diamonds from the South Lobe of the Karowe mine. To recover two plus-500 ct diamonds in 10 months along with the many other high-quality diamonds across all the size ranges is a testament to the unique aspect of the resource at Karowe and the mine’s ability to recover these large and rare diamonds.

“Operations at Karowe have continued through 2020 and operational challenges, due to COVID-19 restrictions, have been met with professionalism by the team. We look forward to a safe finish to 2020 and continued success at Karowe as we remain focussed on strong operations to ensure maximum resource performance.”

Rafaella considers processing options after positive TOMRA XRT ore sorting tests

Sensor-based ore sorting test work from TOMRA Sorting Solutions has shown the potential for lowering the planned capital expenditure and operating costs associated with developing the Santa Comba tungsten-tin project in Galicia, Spain, project owner Rafaella Resources has reported.

The “exceptional” ore sorting results showed a 50% rejection of un-mineralised rock and an approximate doubling of feed grade, which would significantly lower the planned process capex and opex, and enhance process efficiency through a simpler process flowsheet, the company said. The 50% cut in process tonnage also reduces the project’s environmental impact, with a far lower volume of waste generated, lower energy consumption per unit of metal produced and reduced water consumption.

The “Grade Recovery Curve” showed the potential for over 90% tungsten recovery with an increased yield of up to 55% of feed mass, it added, while testing of the low-grade ores showed viable recovery from over 2 Mt of mineralisation not currently factored into the project’s economics.

The program tested two bulk samples selected from assayed drill core crushed to two size groups: +8 mm to -20mm and +20 mm to -40 mm. Sample No. 40 was circa-1,100 kg of average grade ore at 0.15% WO3, while Sample No. 41 was circa-250 kg of low-grade ore at 0.05% WO3.

TOMRA’s conclusion in its report was that “the results from this test work were positive for both sizes and samples. Significant upgrades of WO3, as well as high recoveries, were achieved in all test runs for sample ‘40’ using X-ray Transmission (XRT), while leaving rather low grades for WO3 in the waste fraction. A calculation has shown that a 90% recovery of tungsten can be possible at a waste removal of more than 50%.

“The low-grade sample ’41’ could be upgraded by a factor of 1.7 to 3. For further calculations, a waste grade between 0.025 and 0.030 is achievable.”

The success of the XRT sorting tests allows several mining and process options, Rafaella says, including:

  • Simplification of the process;
  • Bulk ore zone mining to reduce operational costs and maximise ore recovery;
  • In-pit sorting and conveying;
  • Bulk underground mining and sorting of wider ore zones using larger and longer stopes;
  • Separate sorting of sub-grade mineralisation; and
  • Sorting of satellite deposit ores prior to hauling to the process plant.

TOMRA estimates a throughput of 1 Mt/y of feed ore and circa-500,000 t/y of pre-concentrate would require two XRT units.

Rafaella’s Managing Director, Steven Turner, said the results from the ore sorting test work have exceeded the company’s expectations.

“The clear discrimination between ore-bearing rock and low grade or barren rock has delivered high recoveries and yields allowing for a simpler process plant,” he said. “The benefits of this simplification will be significant once the metallurgical studies are completed. These results are now being fed into the feasibility study that is in the final stages of completion.

“The company looks forward to providing the market with these exciting updates on the fast tracking of its flagship project over the coming weeks.”

Santa Comba is a brownfield project with a 5.1 Mt JORC 2012 compliant near-surface inferred resource at 0.203% WO3 and 0.014% Sn and an underground inferred resource of 234,000 t at 0.95% WO3 and 0.28% Sn.

TOMRA makes recovery promise to diamond miners

TOMRA is offering diamond mining customers a guaranteed diamond recovery of greater than 98% with the use of its sensor-based ore sorting technology.

The company is making this guarantee alongside a promise of 100% detection in the specified range, irrespective of luminescence profile or coating.

As the company says, maximising diamond recovery while optimising costs is the top priority for every diamond producer.

“With TOMRA’s holistic approach and cutting-edge technologies, both can be achieved to deliver outstanding results,” it said, adding that its X-ray Transmission (XRT) diamond recovery technology has helped recover some of the largest and rarest gemstones in history.

TOMRA says it approaches every project as a partnership with the customer to deliver a complete solution that meets their operational and business requirements.

This begins with a detailed analysis of the customer’s requirements and operational needs.

TOMRA – Operations Hub Johannesburg

Working collaboratively, it assists in developing a tailor-made flowsheet redesign that combines its XRT technology with its Near Infrared (NIR) and Laser solutions as needed. This collaborative approach continues throughout the project, with testing at its Test Center in Germany and, on-site, as required, through to installation and beyond.

More recently, this approach has been enhanced with the development of a remote testing option.

“The complete solution can also include the web-based TOMRA Insight platform that turns all the sorters into connected devices for monitoring and tracking the system’s performance,” the company said.

Once the system is fully operational, TOMRA offers its Service Level Agreement to ensure its solution continues to deliver the desired results.

“The tailored agreement can include on-site presence as required, seven days a week product support, application engineer visits, tiered urgency support, targeted site response, training, as well as spare and wear parts coverage to ensure maximum uptime and protect the customer’s investment,” the company said.

Advanced technologies adding value

TOMRA’s XRT technology recognises and separates material based on its specific atomic density. It uses a cutting-edge X-ray camera with DUOLINE® sensor technology to measure spectral absorption information.

TOMRA’s proprietary high-speed X-ray processing unit uses the data to produce a detailed “density image” of the material. The result is a high level of purity in sorting materials, irrespective of size, the degree of moisture or surface pollution present, TOMRA says. This makes TOMRA’s XRT high-capacity sorters effective in the recovery of free, liberated diamonds at high feed rates up to 300 t/h.

TOMRA’s NIR sorters recognise and separate kimberlite and waste rock based on their chemical composition. This technology is useful in upgrading lower grade run of mine and stockpiles, producing a kimberlite concentrate for further processing, the company says.

Marie-Claude Hallé had first-hand experience of how TOMRA’s solutions can add value to diamond mining operations when she held the role as Marketing Operations Manager for diamond exploration and producing company, Stornoway Diamonds.

“You have to really envision that TOMRA has actually changed the game in terms rough diamond recovered around the world and allowed producers to access large exceptional quality goods that perhaps in the past would be crushed to pieces,” Hallé said.

Customised solutions for kimberlite, lamproite and alluvial applications

With its customised approach, TOMRA says it can deliver on its promise of guaranteed results both in hard-rock kimberlite/lamproite and alluvial deposits – each of which presents their specific challenges.

In kimberlite, the challenge is to recover “needle in a haystack” diamonds, which requires controlled crushing of kimberlite ore to avoid damaging or breaking the diamonds, the company says.

“High waste dilution impacts the crushing energy needed and further increases diamond breakage risk,” TOMRA says. “Utilising TOMRA NIR technologies, we can remove non-diamond bearing material, not only improving the crushing profile of the ore, but also increasing the value of each tonne of ore processed. TOMRA NIR waste sorting technology can make diluted marginal kimberlite deposits economic.”

Additionally, complex, energy- and water-intensive kimberlite liberation processes, and the cost of transportation for crushing and processing, are challenges facing modern diamond miners today.

“TOMRA’s XRT and NIR technologies, which offer extremely high concentration factors, allow the production of hand sortable, ultra-high grade concentrates in as little as two stages compared to up to seven in traditional methods,” the company claims.

The challenge of economically mining low-grade alluvial deposits is due to their typically lower grade and the sporadic nature of the deposits.

The high recovery performance of TOMRA’s XRT technology enables single-stage or double-stage diamond recovery, offering a drastically lower operating cost and capital investment so that mining marginal deposits becomes economically viable, according to TOMRA.

“Another advantage of TOMRA’s XRT solution is that it can operate as a dry process, which dramatically reduces its environmental impact and operational complexity,” it says. “Besides, it opens the door to new opportunities, making it possible to mine deposits in arid areas where water access is minimal.”

TOMRA XRT machines have proved effective in alluvial operations, the company says.

One such case is that of the Lulo mine in Angola, operated by Lucapa Diamonds, where TOMRA XRT technology is used to process material between 18 and 55 mm in size and allows the recovery of diamonds of up to 1,100 ct – and where it has recovered Angola’s second-biggest diamond on record, a 227 ct stone in 2017.

Stephen Wetherall, Lucapa Diamonds Managing Director at the time of the recovery, said: “The recovery of the 227 ct diamond using the new XRT circuit justifies our investment in TOMRA’s large diamond recovery technology, which has more than paid for itself with the recovery of this one stone alone.”

Optimised flowsheet

TOMRA is in the unique position of being able to offer diamond operations a full XRT recovery flow sheet to 2 mm that delivers concentration factors up to 1 million with a much-reduced number of concentration stages, it says.

Geoffrey Madderson, Diamond Segment Manager for TOMRA Sorting Mining, explains: “TOMRA XRT technology replaces multiple stages of diamond concentration by virtue of its ability to concentrate diamonds to a hand sortable product after only a single step. This concentration factor allows for the removal of multiple recovery steps, drastically reducing both the capital investment and operational costs to recover diamonds.”

Geoffrey Madderson, Diamond Segment Manager for TOMRA Sorting Mining

TOMRA’s XRT technology can replace traditional methods such as dense media separation (DMS), wet magnetic separation and XRL final recovery with single-stage solutions for +8 mm and double-pass for -8 mm +4 mm particles, it claims.

“TOMRA’s solution eliminates up to seven concentration stages, dramatically reducing the complexity of the supporting plant and infrastructure,” the company says. “This results in significantly lower power and water consumption, which not only reduces costs, but also the environmental impact of the recovery process.”

An additional benefit of TOMRA’s solution is that it is a fully automated process, so there is no manual handling during pre-concentration and recovery, which has positive implications on security and eliminates human error, resulting in greater accuracy, the company says.

Recoveries

TOMRA’s sorters process these volumes with great efficiency, finding more diamonds than other, traditional separation methods – including coated and low- or non-luminescent diamonds, the company says.

The performance of its XRT sorters is independent of the “heavies” content in the feed, and is ideal for processing high-yielding ores unsuitable for DMS. The result is an exceptionally high recovery rate, it claims.

“TOMRA guarantees >98% recovery: that is how confident we are in our technology,” Madderson states.

With TOMRA’s sorting solutions, diamond producers can install large diamond recovery systems with a small capital investment and operate with a fraction of operating expenditures per tonne compared with traditional recovery methods such as DMS and XRL, it claims. In addition, the economic recovery of ultra low-frequency exceptional diamonds of +32 mm is now possible.

“TOMRA’s ability to deliver not only a technology that can detect such large diamonds, but also an economical process solution for the recovery of ultra-rare, exceptional diamonds is what sets it apart from its competitors,” Madderson said.

“This is the reason that, to date, TOMRA XRT has become synonymous with the recovery of extraordinary diamonds from all around the world.”

TOMRA receives positive ore sorting signals as virtual offering gains pace

While the effects of COVID-19 continue to be felt across the mining equipment, technology and services (METS) sector, the time away from the office or mine site has enabled many within the industry to carry out work that could lead the industry into a whole new growth cycle.

The jury is out on when such an upturn could occur – these economic studies will not necessarily result in a positive mine investment decision – but this activity, coming alongside billions of dollars of investment from governments and central banks, bodes well for the future.

One company that has witnessed this increase in interest is TOMRA Sorting Mining. The Germany-based firm, known to miners for providing high-tech sorting solutions, including X-ray Transmission (XRT) technology, has received many enquiries since lockdowns were established across the globe in March and April, according to Jens-Michael Bergmann, Area Sales Manager for Europe, MENA and India.

“The number of enquiries has definitely increased since COVID-19 restrictions were put in place,” Bergmann told IM last week. “There are many people deep into prefeasibility or feasibility studies (FS) on projects who need ore sorting data for this. They are very happy to have this provided remotely.”

Jens-Michael Bergmann, Area Sales Manager for Europe, MENA and India, TOMRA Sorting Mining

Such remote work could range from the inspection of photos sent from smart phones or distributed within MS Teams videoconferences, to more advanced analysis and testing of material, Bergmann explained.

Fortunately, TOMRA is setup for this type of remote interaction. Its initial sales process – where mining companies will at this stage be considered ‘leads’ – usually involves the exchange of emails/phone calls, inspections of photos/videos and a few kilograms of material to sample.

The next stage would include the performance test, which could involve hundreds of tonnes of material and usually a visit to the Test Center in Wedel, Germany.

It is this stage that has been revamped recently to cater to the lack of travel options for clients.

TOMRA has opened virtual testing facilities that enable miners to take informed purchasing decisions for their processing plants, regardless of where the client may be located.

This brings the capabilities of the company’s Test Center to the client, offering a video of their material being sorted in an ore sorting unit and a follow-up detailed report including assays (supplied by a sub-contractor), ore sorting data and an estimation of just how optimal a sort could be achieved on that material when it is subjected to XRT technology.

“You have a complete document and resource to base economic decisions on,” Bergmann said.

TOMRA, last month, presented the Virtual Demonstration and Test Solution to the market as a “temporary” platform, but recent experience shows the potential for this becoming part of the company’s standard offering.

“We understand it currently to be a temporary version, but in recent days we have had some positive replies that make us think we can continue to offer it in the future to certain clients,” Bergmann said.

In a COVID-19-affected world where every decision to travel on a plane requires strong justification, flying from North or South America, Asia, or Australasia to Europe for a one-day test is unlikely to be warranted.

Such a trip involving operations teams, executives and metallurgists is more likely to take place when a detailed week-long trial examining the effects of sorting technology on roughing, cleaning and scavenging stages is planned, Bergmann said.

“We don’t think in the future we will go virtual permanently, or personal permanently,” Bergmann said.

Testing time for tungsten-tin

TOMRA only established these virtual facilities on May 12, but it has already carried out four or five of these tests for clients that either had sent samples to Wedel ahead of lockdowns or dispatched them during the period when travel was restricted.

Mike Hallewell, Consultant at MPH Minerals Consultancy Ltd

One of these tests has been for Tungsten West, the owner of the Hemerdon tungsten-tin asset in Devon, England.

Previously owned and operated by Wolf Minerals Ltd, Hemerdon has been offline since late 2018 after Wolf fell into financial trouble as the operation failed to reach expected recovery rates.

According to Tungsten West, Hemerdon hosts the world’s fourth largest tungsten resource, with the potential to become the world’s largest.

With eyes on re-starting the operation and improving recoveries, the company has been looking at XRT ore sorting technology to ensure the new operating plan stacks up over the long term.

Mike Hallewell, Consultant at MPH Minerals Consultancy Ltd, has been helping the company explore its processing options and said the virtual test work TOMRA carried out on behalf of Tungsten West was part of studies looking into a re-start of the mine.

“They are at scoping study level and now moving towards feasibility level,” he told IM. “Ore sorting is a key component of that next phase.”

Hallewell said the recording of the virtual test on an Hemerdon ore sample at Wedel was well received by both himself and Tungsten West.

“You have got to convince the Plant Manager that is operating the plant that it (XRT ore sorting) is something he will be comfortable with, on top of making the case to boards of directors that may not have the same metallurgical expertise as the operation guys,” he said.

“When people see particles being blown by the air jets, it greatly enhances the visual understanding of the separation technique being employed,” he added. “To see is to understand.”

TOMRA has done well replicating the experience project and executive teams would have had in Wedel in person with this testing, Hallewell said.

“They have thought about the things that a client would want to do and see if they were there,” he said.

“They provide a powerful video of the air jet stones hitting the sides, the bins where material is deposited into, and even go as far as putting their hands in that bin at the end to try and replicate that tangible feeling of the sort.”

Future indicators

The more successful TOMRA is at replicating the in-person experience virtually, the more likely these ‘temporary’ options will become part of its permanent offering.

Another area that could ‘go virtual’ in the future is the maintenance and servicing side of TOMRA’s ore sorting business, Bergmann believes.

“The maintenance side is moving in that direction already to a certain degree,” he said.

“Since everybody is currently facing travel restrictions, the infrastructure for accurate virtual maintenance will, in the future, be set up in all plants. The awareness of the need to do this will increase,” he said.

Certain parts of the contract negotiation process could also go virtual, such as “all the unloved paperwork”, Bergmann added.

But, the installation and final signoff of these machines is unlikely to make this transition, at least in the near term.

That is despite an XRT ore sorting machine from TOMRA recently being installed at Sotkamo Silver’s mine in Finland when lockdown conditions were still in place.

On this installation, specifically, Bergmann said: “A lot of pre-commissioning work on that unit took place ahead of the delivery and it was a representative from Outotec – a salesperson with engineering experience – that was able to commission it with remote assistance from our specialists in Germany.”

Looking past the virtual offering, TOMRA could be set for an upturn in business in the near- and medium-term if the influx of enquiries it has recently received is converted into, first, demonstrations and, then, sales.

“In terms of first inspections of material, I would say we have had around 50 enquiries in this lockdown period,” Bergmann said.

“While everyone is planning now, if they hit the investment button, there could be a lot of orders backed up. The manufacturing could run into a bottleneck.

“It’s potentially a positive problem, but a problem nonetheless.”

Considering the amount of investment being pledged by governments to stave off an economic downturn, TOMRA is unlikely to be the only METS company facing such a ‘positive problem’.

Sotkamo Silver chases processing efficiencies with Outotec-TOMRA XRT solution

Sotkamo Silver is looking to reduce the amount of material it grinds and floats at its silver operation in Finland through the introduction of X-ray Transmission (XRT) ore sorting technology.

The company said it began pilot testing of the XRT machine in May after the unit was supplied and successfully commissioned at the mine by Outotec and TOMRA. Outotec and TOMRA have been cooperating on the supply of Outotec-branded sorting solutions for the mining and metallurgical industry since 2014.

Sotkamo’s trial pilot testing builds on previous test work at TOMRA’s testing facilities in Germany.

Previous XRT ore sorting test work carried out by TOMRA on 2,200 kg of Sotkamo samples showed the silver content from low-grade ore increasing some 1.9 x to 116 g/t Ag, while the average silver content in ore rose 1.43 x to 195 g/t Ag. In addition to this, about 60% of the rock previously classified as low-grade ore was removed as gangue with the testing, with some 43% of rock reporting as gangue from the average grade ore samples.

Following this work, back in 2018, Sotkamo Silver said it was looking to install an Outotec-TOMRA XRT ore sorter in the process flowsheet after two-stage crushing (jaw and cone crushers) had taken place and the rock was some 30-70 mm in size.

In the update today, Sotkamo Silver said the XRT technology can scan every feed particle to identify the relative atomic density differences within particles and then separate desired high-grade particles from the barren material pneumatically.

It said sorting of marginal ore would be carried out after primary crushing and it was expected to reduce roughly 50% of non-ore material going into the grinding and flotation process.

“This improves significantly the energy efficiency as less material is grinded, and also material efficiency as marginal ore can be exploited and processed to mill feed,” the company said, adding that leftover barren material would be used as rock-fill in the underground mine.

During the first three months of 2020, around 129,000 t of ore was processed at the silver mine, yielding some 391,000 oz of silver, 462 t of lead, 958 t of zinc and 998 oz of gold in the concentrates.

TOMRA takes XRT ore sorting testing virtual in face of COVID-19 restrictions

TOMRA Sorting Mining is bringing ore sorting testing capabilities to its stay-at-home mining customers though the development of virtual testing facilities that enable them to take informed purchasing decisions for their processing plants, regardless of location.

This is the latest action in the company’s plan to provide its customers the support they need to take their business forward in the face of current COVID-19-related restrictions.

“Ensuring business continuity at this time is of paramount importance for mining operations,” TOMRA Mining said. “This includes taking forward ongoing investment projects in sorting equipment to improve their efficiency and the quality of their product.”

TOMRA Mining is leveraging digital technology to help customers identify the best sorting solution for their mine by offering them remote access to its Test Center in Wedel, Germany, a facility that has capabilities for all applications, according to the company.

“TOMRA’s temporary Virtual Demonstration and Test Solution will enable mining companies to test the sorting solutions on their samples without leaving their office,” the company said. “They will just need to book a session with their TOMRA sales representative and ship a sample of their minerals to the Test Center, which will conduct the test.”

Once testing is complete, mining customers will receive a video of their material being sorted and be able to discuss the results with a TOMRA sales person and the Test Center’s experts via video call, the company said. “With their support, they will be able to make a decision on the following steps and take the project forward without delay,” it added.

Albert du Preez (pictured), Senior Vice President and Head of TOMRA Sorting Mining, said: “At TOMRA, we work closely with our customers to devise the solution that is perfect for their operation. The visit to one of our test centres can be an important step in this process, as it enables them to work out with our teams the best combination of technologies and develop the flowsheet for their ore sorting plant.

“With this virtual solution, we are able to provide this support, taking our Test Center to our customers’ office so they can make an informed decision on an important investment. This means that they are able to take their business forward in the current situation.”

TOMRA’s test centres play a key role in the company’s collaborative approach to supporting customers with their ore sorting requirements, according to the company. Based on the tests conducted on TOMRA equipment with material from the customer’s mine, the centre can provide an initial feasibility study and detailed reports on the machine’s performance with the sample. With this information and the advice of the centre’s experts, the customer can proceed with their investment with confidence, the company says.

The opportunity for the customer to see first-hand the equipment at work on their sample and discuss the options with TOMRA’s team provides important added value, according to the company.

This was the experience of John Armstrong, VP Mineral Resources at Lucara Diamonds, who visited the Test Center in Wedel when researching a solution for the diamond mine in Karowe, Botswana.

“We gained a lot of confidence in the people at TOMRA, in the technology that they were presenting to us, and the possible solution that it provided to the Karowe mine…We could also see that they had already gone down the road of the next step in X-ray Transmission (XRT) technology, so they were not just focused on one particular module to present to us, but they were working on different modules.

“That helped alleviate some of our concerns about the robustness of the platform and the technology itself, which ultimately led us to use TOMRA as the solution.”

Lucara has since gone on to recover some of the largest diamonds in history with the TOMRA XRT system that was installed following this visit to the Test Center.

In addition to developing this Virtual and Demonstration and Test Solution in reaction to the COVID-19 outbreak, TOMRA has increased stocks of critical components to ensure its ability to fulfil current and future orders, and to ensure the supply of spare parts without disruption.

And the company is leveraging digital technology not only to take the expertise of its test centres to customers, but also by using its remote service and training tools to support their equipment while respecting social distancing safety measures, it said.

XRT ore sorting shows promise at Vendetta Mining’s Pegmont project

Following positive X-ray Transmission (XRT) ore sorting test work on the Pegmont asset, in Queensland, Australia, Vendetta Mining is looking to apply this technology in its next mining study at the lead-zinc project.

The test work, conducted at TOMRA’s testing facility in Sydney, Australia, concluded that the XRT sorters could distinguish between high-density/high-grade feed and lower-density waste material at Pegmont, the company said.

Vendetta said: “At Pegmont, the potential advantages of XRT material sorters is that they could allow plant feed material to be screened prior to grinding and flotation, removing lower density external dilution (waste) and lower-grade internal dilution (material below cutoff).”

Potential capital cost savings occur through the reduced mill throughput while potential operating costs savings occur through reduced water and reagent usage, less pumped tails and lower energy requirements, it said.

The test work envisages that sorted waste product would be ejected and stacked for dry disposal (dry stack tailings).

Vendetta said: “Flotation recovery often improves with increasing head grade. Such a relationship exists in the metallurgical test work performed at Pegmont to date. The higher head grades obtained from the ore sorted product are anticipated to result in enhanced flotation recovery.”

The testing involved material from two drill hole intersections from Zone 5 and one from Zone 2 at Pegmont. The sulphide intersections were selected in order to test different lead to zinc ratios (Zone 5 vs Zone 2) and internal grade distributions, it said. All samples included diluting quartzite material from the hangingwall and footwall.

The conclusions of the XRT ore sorting preliminary test work on the three drill intervals are it can successfully remove the external dilution from the samples; and successfully remove internal diluting material from within the higher-grade intervals.

The total mass tested amounted to 139.2 kg, with the mass pull (weight % of feed recovered) ranging from 44.3% to 70.6% (a weighted average of 62.3%).

The lead grade improved from 18% to 88%, a weighted average of 42%; zinc grade improved from 21% to 72%, a weighted average of 38%; lead recoveries ranged from 83.2% to 90.2%, a weighted average of 88.5%; and zinc recoveries ranged from 76.4% to 92.2%, a weighted average of 85.9%.

Vendetta said that while these results were highly encouraging, they are preliminary. “In order to apply material sorting results in an updated preliminary economic assessment (PEA) study, pilot scale test work is necessary,” the company said.

TOMRA recommends 600 kg of material is required for each ore type at Pegmont. Vendetta plans to pursue this test work and expects these samples will be obtained from the next drilling program. Samples will be obtained from Zone 1 transition, Zone 2-3 sulphide and Zone 5 sulphide.

Michael Williams, President and CEO, said: “At Pegmont, the XRT sorter can clearly differentiate between high density/high grade feed from lower density waste material at Pegmont. We are excited by the prospects of advancing to pilot scale test work and applying this commercially available technology to the next mining study.”

The existing Pegmont PEA contemplated a production rate of 1.1 Mt/y, which corresponds to two TOMRA COM XTR 1200 – generation one ore sorters, Vendetta noted.