Tag Archives: bulk ore sorting

Future Metals makes mining and processing ‘breakthrough’ at Panton

Future Metals says the latest flotation and ore sorting test work for its Panton platinum group metals project in Western Australia represents a mining and processing “breakthrough”.

Results from bulk ore sorting and flotation optimisation and repeatability test work for its Panton project demonstrated a significant de-risking for the future mining and processing of the company’s 6.9 Moz palladium-equivalent JORC resource and provide a credible path towards developing a low capital, high margin PGM-Ni operation, it said.

The company has also commenced scoping study and test work evaluation with PGM downstream processing technology providers.

Previous test work on Panton concentrate has demonstrated recoveries of 99%-plus for a majority of metals contained in the concentrate. These processes produce upgraded metals products for direct sale to refineries, or refining on site, improving payabilities, reducing logistics costs and reducing emissions relative to the smelting process route.

Initial assessment of the Lifezone Metals Ltd hydrometallurgy technology – which is already in use at the Pilanesberg Platinum Mines operation on South Africa’s Bushveld Complex – suggests that this would be a low capital flowsheet addition with significant operating and economic benefits.

Jardee Kininmonth, Managing Director of Future Metals, said: “We have now demonstrated a credible metallurgical solution which places Panton firmly on the development pathway. Panton is the highest grade PGM deposit in Australia, enabling us to progress a low capital and high margin operation with significant growth upside.

“Optimisation and variability flotation test work has demonstrated highly repeatable results with strong recoveries at high concentrate grades.”

New flotation results from this latest program of optimisation and variability test work yielded positive results on the high-grade chromitite samples with PGM recoveries of 75.7-81.4% with concentrate grades from 167-387 g/t PGM with an average of 286 g/t PGM.

Kininmonth continued: “The ore sorting results are significant, as it is the key to increasing mineable tonnes while ensuring the ore reporting to the mill is high grade. This allows for increased economies of scale within the mine, utilising conventional underground mining methods, while decreasing processing plant capital costs by increasing the grade of the mill feed, with negligible losses of high-grade ore.”

Following “sighter” test work success, a bulk sorting test was completed with Steinert Sorting Solutions using its X-ray Transmission (XRT) and 3D Laser combination sort program, due to the chromitite in the Panton samples being substantially higher in atomic density.

The bulk test work involved compositing separate chromitite and dunite samples to replicate the expected feed mix from a mine stope. The chromitite and dunite were crushed and screened into to three size fractions: plus-25 mm, plus-10 mm, and -10 mm.

The bulk ore sort test work validated the sighter test work on multiple size fractions, demonstrating 96.7% recovery of high-grade ore and rejection of low-grade and waste, increasing the PGM grade of the potential mill feed by 10.7% and reducing the throughput volume by 12.7%.

Kininmonth concluded: “Additionally, we have been progressing discussions with potential technology partners to assess a low-capital downstream integration option at Panton. Downstream integration enables the production of high-margin metals products while also significantly decreasing the emissions profile associated with those products, thereby differentiating Panton from the majority of South African and Russia producers, which use coal-fired power and generate other emissions such as sulphur dioxide.

“Downstream processing also closely aligns Panton with the Australian Government’s critical minerals strategy which incentivises onshore upgrading and development of strategically important deposits such as Panton.”

MineSense continues growth trajectory with new South America HQ in Chile

MineSense Technologies officially opened its regional headquarters and service centre for South America in Santiago, Chile, this week, in another move to capture growth across one of the world’s key mining hubs.

Attended by senior executives and a MineSense workforce of over 50 hired so far in Chile and Peru, the ceremony celebrated the opening of a 3,000 sq.m facility in an industrial park in the Pudahuel district.

The headquarters includes corporate offices and a manufacturing area that increases service and production capacity to supply ShovelSense technology to meet South American and global demand, the company said.

Jeff More, President and CEO (pictured on stage), was on hand to cut the ribbon. He was joined by Victor Aguilera, member of the Board of Directors of MineSense Technologies Ltd and General Director of Aurus Investments; Claudio Toro-Salazar, Executive Vice President, Business Development; and Monica Feregrino, VP Operations.

MineSense, through the deployment of its ShovelSense solution, has been gaining ground in the bulk ore sorting space across South America.

Earlier this year, it deployed a second shovel-based unit at Teck Resources’ Carmen de Andacollo mine, in Chile. This followed an earlier successful trial at the operation.

It has also recently gone live with a deployment at Antamina, Peru’s largest mine, and has been trialling the XRF-based technology at Hudbay Minerals’ Constancia mine, also in Peru.

The ShovelSense system, through a sophisticated suite of sensors and algorithms, improves orebody visibility bucket by bucket in real time during the loading process, according to the company. Trucks are then automatically diverted to the correct location, increasing value and revenue realised during the mining process. The technology also creates reductions of CO2 emissions per tonne of ore produced, consumption of processing chemicals and reagents, energy and water, while maximising metal recovery, MineSense says.

To support mine site operations and their ore decision making, MineSense also provides 24/7 data room technical support for continuous monitoring of all elements of system performance.

NextOre, First Quantum fully commission ‘world’s largest bulk ore sorting system’

A 2,800 t/h MRA ore sorting installation at First Quantum Minerals’ Kansanshi copper mine in Zambia is now fully commissioned and using diversion hardware, Chris Beal, CEO of NextOre, told RFC Ambrian and Stonegate Capital Partners’ Copper Pathway to 2030 webinar on Tuesday.

Presenting alongside speakers from RFC Ambrian, Oroco Resource Corp and First Quantum Minerals, Beal revealed that the diversion process on what he said was the highest capacity bulk ore sorting operation in the world had now commenced, some 16-17 months after the magnetic resonance (MR) based system was installed and testing commenced.

“After a one year sensing-only trial, Kansanshi has now gone forward and commissioned and tested diverting hardware in May that has allowed them to fully transform into an inline bulk sorting system,” he said.

“With the validation of that having just gone by, this now represents the highest capacity sorting plant in the world.”

NextOre was originally formed in 2017 as a joint venture between CSIRO, RFC Ambrian and Worley, with its MR technology representing a leap forward in mineral sensing that, it said, provides accurate, whole-of-sample grade measurements.

Demonstrated at mining rates of 4,300 t/h, per conveyor belt, the technology comes with no material preparation requirement and provides grade estimates in seconds, NextOre claims. This helps deliver run of mine grade readings in seconds, providing “complete transparency” for tracking downstream processing and allowing operations to selectively reject waste material.

The installation at Kansanshi is positioned on the sulphide circuit’s 2,800 t/h primary crushed conveyor belt, with the system taking precise measurements every four seconds for tonnages in the region of 2.5 t to a precision of +/- 0.028%.

“Magnetic resonance technology, in particular, is very well suited to high throughput grade measurement – it is measuring all of the material that is going through,” Beal explained. “And these sensors like to be filled with more material.

“We hope to go larger from here. And we, in fact, have projects ongoing to do that.”

This wasn’t the only reveal Beal provided during the webinar, with the other announcement slightly smaller in scale, yet no less significant.

Seeking to address the lower end of the bulk ore sorting market, the company has come up with a mobile bulk sorting plant that is powered by MR sensors.

This solution, coming with a capacity of up to 400 t/h, has now found its way to Aeris Resources’ Murrawombie mine in New South Wales, Australia, where it is being used for a trial.

At Murrawombie, the setup sees an excavator feed a mobile crusher, with the crushed material then passed to the mobile ore sorting installation (the conveyor, the sensor, the diverter and supporting equipment). The system, according to Beal, provides bulk ore sorting results in a cost- and time-efficient manner.

It has been designed to suit small mines and those seeking to monetise historical dumps, or to provide a rapid test method for bulk sorting to support a potentially much larger bulk sorting plant, Beal explained.

The fully-diesel setup is destined for copper operations globally and potentially some iron ore mines, he added.

Metso Outotec and Malvern Panalytical to collaborate on bulk ore sorting projects

Metso Outotec and Malvern Panalytical have signed a collaboration agreement to, the OEM says, provide sensor-based bulk ore sorting solutions to the mining industry.

The combination of the companies’ expertise in crushing and bulk material handling solutions, and ore analysers enables the parties to offer an industry-leading portfolio of solutions for bulk ore sorting, Metso Outotec said.

“With this offering, mining customers can substantially improve the head grade by pre-concentrating the ore at the crushing stage and, thereby, reduce their energy consumption and related environmental footprint in the comminution stage,” Metso Outotec said.

The agreemeent will see Metso Outotec’s crushing and bulk material handing solutions integrated with Malvern Panalytical’s cross-belt analysers. The latest generation of cross-belt analysers, CNA³, has been designed for tough environments such as underground mines, and features the Sodern neutron solution, which is powered by Pulsed Fast Thermal Neutron Activation (PFTNA) technology. The technology has been used by Anglo American, among others.

Rashmi Kasat, Vice President, Digital technologies at Metso Outotec, said: “Sustainability is a top priority for our entire industry. Collaboration with partners like Malvern Panalytical will allow us to meet the industry’s increasing sustainability and resource efficiency needs in an enhanced way in the early comminution stage. Sensor-based bulk ore sorting and data-driven analysis upgrades low grade or waste stockpiles making them economical and far less energy-intensive to treat.”

Jarmo Lohilahti, Sales Manager at Malvern Panalytical, said: “Malvern Panalytical’s cross-belt analysers provide high-frequency online data for cost-efficient bulk material analysis of major commodities. This collaboration enables customers to benefit from the in-depth know-how from both companies.”

Renato Verdejo, Business Development Lead for Bulk Ore Sorting at Metso Outotec, concluded: “Bulk ore sorting allows waste rock elimination early in the process and, when combined with Metso Outotec’s complementary crushing and bulk material handing solutions portfolio, it provides more sustainable flowsheets for our customers. Enhanced bulk ore sorting will contribute to Metso Outotec’s Planet Positive portfolio.”

On the particle sorting side of the business, Metso Outotec and TOMRA have a non-exclusive cooperation in place to supply particle ore sorting solutions for the mining and metallurgical industries.

TOMRA on achieving mining’s ‘circular economy’

TOMRA, a global leader in sensor-based technologies, says it understands that technology alone is not enough to create a closed-loop circular economy, with public policy, consumer engagement and collaboration across the value chain are necessary too.

Making the shift from “linear to circular” to build thriving economies requires radically lessening the environmental impact of extracting raw materials, reducing the use of primary resources, designing waste-free products, harnessing materials to keep them in use and implementing technologies to ensure the system is regenerative.

ReSociety

TOMRA says it is well positioned to contribute to the transition to a circular economy by collaborating with key players across the value chain to develop new methods, processes, technologies and business models.

To this end, it has created ReSociety, a global collaborative initiative to re-think, re-act and re-start our world for a more sustainable future.

“It is a place for industry, policy makers, companies and consumers to share ideas, increase awareness, collaborate with solution enablers and drive impactful change,” the company says. “It is also a hub in which TOMRA proactively shares its vast research and multi-national studies on holistic waste management systems, which have been indispensable in developing the circular value chains.”

Dr Volker Rehrmann, Head of Circular Economy, TOMRA, says: “Our commitment to the circular economy is unequivocal. Until recently, it was unheard of having players from the entire value chain at one table. From chemical companies to converters, retailers and brand owners, waste management companies and recyclers – there’s true dedication in finding solutions. We take pride in doing our part: sharing our know-how, developing new solutions and striving to make our planet more sustainable every day.”

Dr Volker Rehrmann, Head of Circular Economy, TOMRA

Dr Rehrmann says the company is aiming to build on the experience it developed in recycling and collaborate with the mining industry to reduce the environmental impact of its operations.

“This means finding green mining solutions that use less energy and water to recover resources – with a consequent reduction in CO2 emissions – and ways to turn waste into value,” he says.

“With the recycling sector, we are working on reducing the mountains of plastic waste; we want to do the same in mining and address the dumps and tailings building up in mines.”

Advanced mining tech with a small environmental footprint

As the world addresses the environmental challenges of our time, the mining industry has an important contribution to make. Mining companies need to find ways to maximise the efficiency of their operations to cut back on the use of water and other resources, while reducing waste and the total impact on the environment as much as possible. Amongst other challenges, they need to effectively address the storage and handling of tailings which pose a potential physical and chemical environmental risk.

TOMRA’s advanced sensor-based sorting technologies can not only significantly reduce the environmental impact of mining operations and, at completion, fully rehabilitate the site. They also enable a much more efficient use of resources. These solutions bring the dual benefits of greater sustainability and better profitability for the mining company.

TOMRA’s sensor-based sorting technology has been shown to significantly reduce the amount of energy and water used compared with traditional methods like DMS (Dense Media Separation), while maximising the efficiency and recovery of valuable ores. An extensive study conducted by Alchemy Process Plants (AlcPro) comparing these processing methods concluded that TOMRA’s solution also brings multiple cost benefits.

AlcPro’s Erik Bruggink explains: “Although capital costs of the separation circuits are similar, with DMS, the additional cost of handling the resultant water from the circuit needs to be taken into consideration together with the associated water use licensing and tailings facilities. In addition, TOMRA’s sensor-based sorting technology requires no reagents, and maintenance costs are limited to the sorting unit and the associated conveyors, screens and chutes.”

Water consumption is a key consideration when assessing the environmental impact of a mine, as it can severely affect local supply. Water management strategies are integral to reducing the mine’s usage and ensure future water security for the communities in the mine’s surrounding areas. The Water Research Commission in South Africa commissioned a project to compile a compendium of best practices and technological innovations in the mining industry with regards to Water Conservation and Water Demand Management, with the study identifying TOMRA’s X-Ray Transmission (XRT) sorting technology as a solution that would lead to substantial improvements in water use efficiency.

José Guilherme Valadares, Project Coordinator of Exploration and Mineral Projects at Vale, says: “By reducing the mine’s water usage and fine-grained wastes, TOMRA’s sensor-based sorting technologies also contribute to improving the issue of wet tailings management and, with that, mitigate the risks associated with tailings dams.”

Vale is now investigating the implementation of sensor-based sorting in several mines and processes in Brazil, TOMRA says

Turning waste into value

TOMRA’s sensor-based sorting technology can contribute to circular economy practices at the mine and processing plant, turning marginal waste into value with a positive impact on both the sustainability and profitability of the operation. This is the case at Wolfram’s tungsten mine in Mittersill, Austria, where TOMRA has installed two COM Tertiary XRT sorters.

Alexander Mosser, Manager Ore Dressing Plant, explains: “The sorting system in the scheelite processing in Mittersill sorts out waste material with a size range of 16-60 mm. This eliminates the grinding and flotation that would otherwise be required for this material. This results in the following savings for the coarse waste material compared to grinding and flotation: 75% lower power consumption and no water and no flotation reagents are required. Another resource conservation: the separated waste is a saleable product to the local construction industry. The sewage ponds are relieved and the impact on nature through local gravel pits is reduced. The sorting system thus not only reduces the footprint of the mine but also of the surrounding gravel pits.”

Sustainability as a facilitator

The proven environmental benefits of TOMRA’s sensor-based sorting solutions bring mining operations additional advantages. They can facilitate obtaining the licences needed to start a mining project by proving the efficient use of water and energy, the significantly reduced amount of waste materials, chemicals/reagents, and lower environmental risks such as tailings dam collapse.

Rare earths mining company Cheetah Resources has obtained a loan from the Canadian Federal Government to purchase a TOMRA sorter for its Nechalacho Demonstration Project in Yellowknife, Canada, on the strength of the sustainable performance of its XRT technology, TOMRA says.

(Left to right) Jeremy Catholique, Mathew Edler and Clarance Pikes from the Nechalacho Demonstration Project team in Yellowknife

The sorting solution will significantly reduce the amount of water and fuel used and eliminate chemicals and tailings from the mining process. Leftover waste rock can be stockpiled for future use or used on infrastructure projects, such as road construction. The aim of the project is to create a low-impact facility for the production of rare earth minerals used in green technologies, which will generate employment and economic benefits in the region.

“We anticipate that, with this project, we will demonstrate the economic feasibility as well as the technical and environmental advantages of sensor-based sorting of rare earths to produce a value-added mixed rare earth concentrate in the Northwest Territories,” David Connelly, Vice President of Corporate Affairs and Strategy at Cheetah Resources, says.

The path to a more sustainable future starts today

Overcoming environmental pollution by enabling the transition to a circular economy is one of the central challenges of the 21st century. Mining has a key role to play as the supplier of the raw materials, but a holistic approach is necessary. Beyond efficient operation and waste management in extracting the primary resources, it is necessary to curtail excessive consumption and ensure products are designed to be reused, and, once at the end of life, easily recycled. Such a holistic approach also includes raising global awareness within the industries and with consumers.

Dr Mathilde Robben, Key Account Manager at TOMRA Sorting Mining, explains: “The raw materials supplied by mining are vital for our modern way of living and are critical for the energy transition technologies. With mining as the entry point for these necessary materials, the circle will never be closed completely. However, this should be seen as an opportunity for the mining industry to re-think the way it fulfils this essential role with minimal impact on the environment, and for sectors downstream to shift focus from the core business to the chain around it, without losing sight of profitability. Re-using can be prioritised by the use of certain metals that are infinitely recyclable and whose inherent durability and anti-corrosive properties contribute to the longevity of the products they are used in.”

Scantech launches GEOSCAN GOLD to help digitalise and control ore quality

Scantech International Pty Ltd has released GEOSCAN GOLD, a premium elemental analyser that, it says, uses the highest specification PGNAA (prompt gamma neutron activation analysis) technology available.

The analyser, which builds on Scantech’s GEOSCAN-M high-performance elemental analyser, provides previously unattainable levels of risk-free, real-time measurement performance to the resources sector to help digitalise and control ore quality, according to the company.

GEOSCAN GOLD provides high-quality, real-time elemental analysis for conveyed flows where precision and short measurement times are essential for optimal control. This makes it ideal for bulk diversion (bulk sorting) and fine control where elements at parts per million levels need to be measured or determined from proxies such as gold, platinum group elements, silver and toxic contaminants (eg mercury, cadmium, chlorine, etc), Scantech says.

The analyser incorporates a high performance proprietary detector array for a “better, cleaner spectrum” at lower concentrations for superior element recognition. The array overcomes limitations of conventional, low efficiency detection systems, according to Scantech. It can also operate at extremely high count rates with negligible pulse pile-up.

“This innovation vastly improves the signal to noise ratio and spectral peak resolution, enabling elemental detection at lower levels,” the company said.

Just some of the advantages of GEOSCAN Gold that Scantech highlighted include:

  • An ultra-compact design that can install between standard idlers;
  • Unmatched proven performance;
  • Operational at completion of commissioning;
  • Customised calibrations;
  • Three models cater for belts 600 mm to 2,400 mm and bed depths to 530 mm;
  • No contact with material or conveyor belt;
  • No sampling necessary during normal operation;
  • No wear parts, therefore, low maintenance requirements;
  • Optional customised SUPERSCAN console;
  • Interface to most process control systems; and
  • Proven short paybacks in many applications (bulk diversion, blending, monitoring, feed forward, etc) to optimise plant performance.

The company says GEOSCAN GOLD measures elements in primary crushed rock in conveyed flows at <100 t/h to >10,000 t/h irrespective of belt speed, particle size, mineralogy, dust, moisture, or segregation/layering,

It covers most elements from carbon onwards in the periodic table, including gold, over various measurement times and concentration levels. It can also analyse selected elements to below 1 parts per million, and even register accurate results where conveyor belts contain chlorine or steel cords.

It can register gold directly over 5-10 minute increments and other elements, including proxies for gold (eg sulphur, copper, etc), with high precisions over each 30 seconds of flow.

Measurement data is used concurrently for various applications: bulk sorting, ore blending, ore reconciliation, ore tracking, feed forward control, metal accounting, etc.

“GEOSCAN GOLD is the new standard in representative, real time, conveyed material measurement using Scantech’s Rocks2data customisation module,” the company said. “Successful performance is already proven in many challenging bulk ore sorting applications in base metals and PGMs. It builds on the very successful, world-leading GEOSCAN-M with over 100 installations in the minerals sector in more than 10 commodities. Paybacks are in a few months and sometimes weeks. Non-contact design minimises maintenance and remote access ensures trouble-free operation and high data accessibility.”

Metso Outotec on ore sorting’s potential ‘revolutionary change’

Metso Outotec stands out among the mining original equipment manufacturers for having publicly acknowledged ore sorting is on its radar.

The Outotec business had a relationship with TOMRA Sorting Solutions dating back to 2014 when the two companies signed an agreement that would see the particle sorting company supply Outotec-branded sorting solutions to the mining and metallurgical industry. Metso, meanwhile, has previously disclosed it was developing “breakthrough proprietary technology to address the demand of high throughput accurate sorting”.

Close to eight months after the two companies merged to become Metso Outotec, IM put some questions to Erwin Huber, Vice President, Crushing and Conveying Systems; David Di Sandro, Business Development Manager – Optimisation and Test Labs; and Rashmi Kasat, VP, Digital Technologies, Minerals, to find out the current state of play with ore sorting at the mineral processing major.

IM: Back in November at your Capital Markets Day, there was mention of ‘AI-powered Ore Sorting Solutions’ during a presentation. Can you expand on what this offering might include? What stage is it at in terms of commercialisation?

DDS: Ore sorting is one of the most exciting recent developments in our industry. With improvements in sensor capabilities and adoption of artificial intelligence (AI), this may well become the revolutionary change this industry needs to sustain itself in the face of diminishing grades and orebody quality.

EH: With our ore sorting solution development, we are targeting the ability to deliver complete offerings of hardware and sensor-fusion platforms as it relates to both bulk and particle ore sorting. These platforms would utilise AI to optimise the feed material for the downstream process. Metso Outotec is uniquely positioned to understand and optimise that plant feed stream with deep knowledge and almost complete technology coverage in both the concentrator and tailings processing areas.

We plan to bring new solutions to the market in the short term and continuously launch new technologies to increase capabilities and capacities when the developments are mature enough.

IM: Will these solutions leverage existing tools within the Metso Outotec product offering? Will they make use of existing agreements with other companies (for instance, the agreement with TOMRA that Outotec previously had in place)?

EH: Metso Outotec carries out its own development of these solutions, and some partnerships are part of it once sensoring and analysing different minerals and elements are not possible with a single or only a few technologies. Mining and concentration are becoming more and more a digital world where breakthrough innovation is finding its space towards efficiency and sustainable possibilities. Smart systems will enable improved equipment uptime, efficiency and remote diagnosis of process and maintenance, and will be the bonding element between our traditional offering portfolio and new technologies.

IM: Previously Metso has talked about the development of a bulk sorting solution: do these ‘AI-powered Ore Sorting Solutions’ fit into that category, or are they more particle sorting solutions?

EH: Bulk ore sorting enables material selection at high throughput flows and particle technology is limited by capacity while bringing the benefit of high accuracy on selectivity.

RK: Bulk sorting is in its early stages in industry and no single sensor can determine minerals content across all ore types and mine sites. This is where AI algorithms play a significant role in ‘self-learning’ ore characteristics, mine site by mine site. It also provides great opportunities to do sensor fusion and more accurately determine the minerals content based on outputs from various sensors and sensor types. AI augments our expert’s tacit knowledge and provides a more reliable way over time to analyse big data generated from online mineral analysis.

IM: Where in the flowsheet do you envisage these solutions going?

EH: The earlier we can remove the gangue from the flow stream, the better our energy efficiency will be by reducing the volume of waste material that is processed by downstream equipment. Deposits in advanced development allow for in-pit backfill bulk ore sorters that may be deployed behind mobile in-pit crushers, or before the coarse ore stockpile where backfilling is not an option. There are several pre-concentration technologies that can be applied at each stage of mineral processing and the ideal operation should combine those tools to remove the liberated gangue at multiple stages of the processing plant in order to achieve the most sustainable process (ie bulk/particle ore sorting, selective breakage, coarse flotation).

IM: Will the benefits of your solution be felt beyond the crushing and grinding stage? Do you intend to use the data generated from the ore sorting solutions to benefit the whole downstream flowsheet?

DDS: One of the benefits of ore sorting is more efficient removal of waste from the process feed. Under certain circumstances, this also means removal of deleterious material which otherwise would adversely affect downstream process performance such as flotation recoveries. In these cases, the downstream benefits are intrinsic. The key would be understanding the geometallurgical mapping of all rock types and their mineralogy, so a philosophy of ‘include or reject’ can be applied on a metallurgical response basis. This mapping can be improved with SmartTag™ and GeoMetso™ technologies from Metso Outotec.

EH: The ability to sort, the geometallurgical mapping and metallurgical response obviously feed back into the block model and allow for more options in the mine plan and life of mine resource recovery, for example with the deployment of low-grade stockpiles. This further enhances the sustainability of the mining operation.

IM: Is the market ready for and receptive to such a powerful ore sorting solution?

DDS: As we all know, for good reason, our industry is full of early adopters rather than innovators. Most operations will need to see the technology succeed elsewhere before increasing their uptake of the technology. The initial implementation will likely occur in partnership with customers whose operations need this technology to be economically viable.

EH: The key is to understand the ore variability through the deposit and through the life of mine. Adopting ore sorting as an integrated processing step does not differ that much from testing and sizing flotation circuits, where small changes in ore properties can affect the overall recovery. It is important to understand these changes and how to react to them during operations.

The confidence level in sensor-based ore sorting testing will grow over time. We already see real-life examples where customers report on ore reserves based on lower cutoff grades due to ore sorting.

IM: Anything else to add?

EH: Despite the fact that the concept of ore sorting, and the sensors required to detect the valuable ore from the waste, have existed for several years, if not decades, the implementation of these systems in full-scale operations have been relatively restricted to particular cases with the right kind of orebody to make the process viable. Implementing ore sorting more broadly remains the challenge and requires the dual application of the right sensors working effectively with the right mechanical handling systems to detect and remove the waste stream efficiently and accurately. The skills required to solve these challenges are not just for the traditional mining and mineral processing engineers, but need to include a cross-disciplinary team addressing the issues from all angles.

This Q&A interview was carried out as part of the IM March 2021 annual ore sorting feature, to be published early next month

CRC ORE simplifies complexity for value

“There are a lot more variables to bulk ore sorting than just the technology,” Jon Rutter says.

The Principal Geologist of the Cooperative Research Centre for Optimising Resource Extraction (CRC ORE), Rutter knows his stuff. He has worked underground in both narrow-vein and mass-mining operations, as well as at large scale open-pit mines; in the base and precious metal arena.

During a presentation at International Mining Events’ IPCC Virtual event in early-February, he shared a slice of this knowledge while reviewing a recent installation project CRC ORE had been involved in at a platinum group element (PGE) operation.

“The intrinsic value of bulk ore sorting comes from the delivered heterogeneity,” Rutter said. “We have got to be able to sense and divert a higher-value pod of material versus an adjacent pod of lower-grade material on a conveyor.

“You essentially want to put more material into the mill that adds value – and not what destroys value.”

Looking at the wider bulk sorting opportunity in mining, Rutter explained the sensor diversion units (SDU) in bulk ore sorting were smaller than what the mine itself can typically offer in the form of a selective mining unit (SMU), which may be comprised of a dig block totalling around 15,000 t.

A truck offers a 100-300 t opportunity, while a shovel typically comes with a 50-100 t opportunity.

Even with a modest conveyor running at a 2,000 t/h rate, an on-board sensor (eg PGNAA or PFTNA) running at a 30 second integration time (the time to analyse one grade) would provide an SDU of 16.7 t. A sensor with lower integration time (eg XRF at 10 seconds) comes in at 5.6 t.

The ability to provide analysis down to this level has enticed several major companies into testing bulk ore sorting solutions.

Anglo American has trialled bulk ore sorting solutions at copper and platinum group metal mines, while BHP recently engaged CRC ORE to examine deployment of cutting-edge preconcentration techniques under its Grade Engineering® platform at the Olympic Dam mine, in South Australia.

The SDU with bulk sorting may be that much smaller than the SMU of a typical mine plan, but lab-level precision is not required for these solutions to work, according to Rutter.

“What I need is the ability to measure the metal content adequately,” he said. “When I say adequate, this incorporates the entire error bar of the system. That system includes the inherent geology, the mineralisation style and heterogeneity. We also need to consider the precision, accuracy and integration time – which is the technology constraint; but we also need to include the weightometers, the flop gates, the diversion gates, as well as that entire mining and materials handling process right from the start – from blasting, loading, hauling and dumping to the plant.

“But for bulk ore sorting what I end up requiring from this combined data is usually a binary decision: am I above or below a certain threshold?”

He expands on the bulk ore sorting (BOS) assessment process: “The other way of looking at this is simply considering it as planned ore loss and dilution. If we go back into that dig block, in that 15,000 t of material, I’ve already incorporated planned ore loss and dilution decisions or parameters into that SMU decision. So, if we look at bulk ore sorting, I am just talking about those different attributes – the error bars of a BOS system – as the inputs or parameters for BOS planned ore loss and dilution – it’s now just at a smaller and more precise opportunity.”

The company took a two-phase approach to the BOS opportunity at the PGE operation in question.

The first phase involved carrying out heterogeneity analysis of the orebody; correlation analysis of PGEs to base metals; selection of sensor technologies (XRF and PGNAA were selected in this case), design, layout and equipment selection for the bulk ore sorting plant; natural deportment analysis of the orebody; development of a preliminary business case; the ore type selection and sampling strategy; and project planning and management.

CRC ORE and the company in question settled on a solution where a Caterpillar 992 wheel loader dropped material off to a system using a combination of grizzly, feeder, sizer, conveyors, diverter, stackers and associated equipment from MMD, used in conjunction with an ore sensing system equipped with both PGNAA and XRF sensors to continuously measure the elemental composition. The PGNAA sensor provided a “penetrative” analysis calculation whereas XRF provided a “surface” sensing calculation, Rutter explained.

An incline conveyor ahead of the diverter gate and the accept/reject stream provided the 30 second integration time the PGNAA analyser required.

Phase two of the project involved online and offline (pre-install) work; sensor calibration; proving the technology; and proving the technology can drive physical separation.

Rutter said the completion of static calibration of the sensors saw the PGNAA sensor 20-30% calibrated, and the XRF sensor 70-80% calibrated.

This outcome harked back to Rutter’s assertion that “bulk ore sorting implementation is not a plug and play opportunity”.

A dynamic calibration in online mode completed under normal conditions was required to get the PGNAA sensor up to speed. This process, meanwhile, solidified the operation of the XRF sensor.

While the two sensors were calibrated in different ways, Rutter showed data that confirmed both were in unison when it came to reading the ore/waste that came through the conveyor (see right-hand graph below).

“The two sensors are independent of each other and fundamentally very different, but they can work well together, or separately,” he said.

CRC ORE was able to prove the technology by running the same sample through the circuit a number of times, as Rutter explained: “We fed 15-20 t of run of mine material into the hopper and repeated the process 15 times, putting the same 15-20 t sample through the system. We could then start to determine the precision and accuracy of the sensors and the system.”

For further verification, the sample was crushed, sub sampled and assayed.

“We wanted a binary response to ore and waste to build confidence,” Rutter added.

Phase three involved the ramp up to production scale, going from, say, 500 t/h to 1,000 t/h; carrying out validation by campaign; and finally integrating with the operation.

There were several lessons all mining companies – and bulk sorting vendors – should keep in mind from such a project, Rutter said.

Operations need to assess the impact of mixing across the entire materials and mining handling process as soon as possible, for one.

“The earlier we can put this data into the system, the better,” Rutter said. “Without a heterogeneity signature, we cannot implement bulk ore sorting.”

He also stressed the importance of timely feedback. Sensor calibration, a secondary crushing/sampling plant and assaying were all required to build confidence in the solution.

Rutter added: “The proper calibration of sensors does require a considerable and ongoing effort…but that is no different from any other process plant or equipment.”

Operators also need to be wary of where they set these solutions up in mines, recognising this heterogeneity dynamic.

“Bulk ore sorting is quite unlikely to be universally suited to the entire deposit,” Rutter said. “The analogue for this is a flotation plant; there are ore types in the mine where you achieve better performance in the flotation plant and others where you get worse performance.”

BHP engages CRC ORE for Olympic Dam bulk ore sorting study

BHP has engaged the services of Australia-based research consortium, the Cooperative Research Centre for Optimising Resource Extraction (CRC ORE), to examine deployment of cutting-edge preconcentration techniques.

Olympic Dam, 560 km north of Adelaide, is one of the world’s most significant deposits of copper, gold, silver, and uranium. This large BHP site is made up of underground and surface operations and conducts fully integrated processing from ore to metal.

The South Australia operation is one of the locations where BHP is actively examining bulk ore sensing and sorting opportunities – techniques within the CRC ORE Grade Engineering® suite of preconcentration technologies.

Grade Engineering is an integrated approach to coarse rejection that matches a suite of separation technologies to ore specific characteristics and compares the net value of rejecting low value components in current feed streams with existing mine plans as part of a system-view.

CRC ORE was requested by BHP to assist in the assessment of bulk ore sorting opportunities at Olympic Dam, it said.

BHP Principal Technology, Lee Bolden, said that as a CRC ORE participant, the diversified miner had watched with interest the sorting and sensing work that CRC ORE is undertaking in open-pit and underground operations.

“It made sense for us to have CRC ORE provide us with valuable insights on this work and input into our bulk ore sorting plans,” Bolden said.

BHP received a high-level bulk ore sorting deployment strategy from CRC ORE for Olympic Dam, along with a framework and calculator for the quantification and ranking of bulk ore sorting strategies at the operation.

CRC ORE also identified the critical work and data required to strengthen the evaluation of bulk ore sorting with the Olympic Dam Project team.

CRC ORE Chief Operating Officer, Dr Luke Keeney, said there were several deployment options among the opportunities assessed.

“We explored sublevel open stoping under the current mining environment, along with block caving as part of future-state mining options,” Dr Keeney said.

As part of the assessment, BHP received a high-level estimate of value from these deployment options.

Dr Keeney said the engagement of CRC ORE at Olympic Dam demonstrated the commitment of big miners to apply innovation to their processes.

“With the need for valuable minerals continuing to grow and mining these minerals becoming ever more difficult, mine operators need to think differently,” Dr Keeney said.

“Bulk ore sorting, and other Grade Engineering opportunities become increasingly competitive and complementary solutions where mined grades decline and mining dilution increases.”

Magnetite Mines up for NextOre magnetic resonance ore sorting pilot at Razorback

Having shown potential in lab-based test work to increase head grades at the Razorback project, NextOre’s magnetic resonance (MR) ore sorting technology is to now get an outing in South Australia at the high-grade iron ore development.

Razorback owner, Magnetite Mines, says it has entered into an agreement with NextOre to supply a mobile bulk ore sorting plant using a magnetic resonance (MR) sensor for a trial of the technology at the project.

The company said: “This advances our exclusive partnership with NextOre and is an important step in our journey to unlocking the potential of the Razorback project. The company is excited by the potential of the NextOre technology to enhance processing of by ‘pre-concentrating’ run of mine ore feed to increase plant head grade.”

The NextOre agreement includes a non-refundable deposit of A$100,000 ($71,418) and contemplates further, staged payments of A$700,000, Magnetite Mines says. The scope covers supply of a full-scale mobile ore sorting plant to site at Razorback for sorting magnetite ore using MR technology during the trial period for the purpose of mine feasibility analysis. The agreement includes milestone dates, with the equipment despatch from the CSIRO Lucas Heights facility, in New South Wales, expected in 2021.

Formed in 2017 by CSIRO, Advisian Digital and RFC Ambrian, NextOre supplies MR ore sorting solutions to global mining companies that applies mineral sensing technology developed by the CSIRO.

Unlike traditional ore sorting technologies that are based on X-ray or infra-red transmission, NextOre’s on-belt MR analyser ore sorting solution allows for the grade of high throughput ore to be measured at industry-leading accuracies and speeds, NextOre says. Due to the high speed of the technology, the integrative system is able to perform the analysis, computation and physical diversion of waste ores down to one second intervals allowing for fast diversion or high-resolution sorting.

As previously reported, the company entered into an exclusivity agreement with NextOre granting Magnetite Mines exclusive use of its MR ore sorting technology for any magnetite processing applications Australia-wide and all iron ore applications in the Braemar (including New South Wales) for a period of four years.

Magnetite Mines Chairman, Peter Schubert, said: “NextOre’s magnetic resonance sorting technology, developed over many years in conjunction with the CSIRO, has a rapid response time allowing unprecedented selection accuracy and speed. The result is potential for a substantial increase in the head grade of plant feed, resulting in lower unit operating costs and a significant improvement in capital efficiency.

“This technology also offers potential environmental benefits, with enhanced water efficiency and reduced tailings volumes.”

He added: “We are particularly interested in the potential of the NextOre technology to increase the grade of ore fed to the concentrator. The bulk trial of this exciting technology will contribute to the study work now underway.”

Chris Beal, CEO of NextOre said: “We are enthusiastic supporters of Magnetite Mines’ vision of unlocking the vast resources in South Australia’s Braemar region. Their disciplined approach, which leverages emerging technologies with well-established mining methodologies, is a testament to the team’s knowledge and experience in the field.

“In our collaborative planning, the Magnetite Mines methodology of carefully integrating mine and mill activities speaks strongly to the ability to generate the maximum value from bulk ore sorting solution. I am thrilled that NextOre can contribute to this transformative project and I look forward to jointly developing Australia’s reputation as a global leader in green resource extraction.”