TOMRA

TOMRA Insight, the cloud-based data platform which enables sorting machine users to improve operational efficiencies, is being rolled out to more industries. Following its successful launch last year by TOMRA Sorting Recycling, TOMRA Insight is now also being made available to customers of TOMRA Mining and TOMRA Food, and for all three of these industries, the platform is enhanced by new features and functionalities. This makes TOMRA Insight even more capable now than it was when successfully launched to recyclers in March 2019.

TOMRA Insight is a subscription-based service that turns sorting machines into connected devices that generate valuable process data. This data is gathered in near real-time, stored securely in the cloud, and can be accessed from anywhere and across plants via a web portal available for desktop and mobile devices (Figure 2).

Felix Flemming, Vice President and Head of Digital at TOMRA Sorting, Wedel/Germany, commented: “By capturing and using valuable data, TOMRA Insight is transforming sorting from an operational process into a strategic management tool. This tool is constantly becoming more powerful as we continuously develop it in response to customers’ needs and priorities. New functionalities and features are released every three weeks – a routine during which TOMRA works closely with customers in pursuit of shared objectives.”

Data captured by TOMRA Insight provide valuable performance metrics that help businesses optimize machine performance. Operating costs are reduced by simplifying spare part ordering and flexible access to data and documentation. Downtime is reduced by monitoring machine health and performance in near real-time, identifying gaps in production and analyzing potential root causes, by supporting the management moving to predictive and condition-based maintenance, and by preventing unscheduled machine shutdowns. Throughput is maximized by evaluating variations and optimizing sorting equipment accordingly. And sorting to target quality is enhanced by having accurate material composition data which enables decisions to be based on more detailed information.

For the mining and mineral processing industries, TOMRA Insight’s ability to collect detailed data from TOMRA’s sorting machines means that previously hidden information can lead to improvements in efficiencies and profitability.

Data captured by TOMRA Insight is analyzed on behalf of customers by TOMRA Mining engineers, and key findings shared in confidential reports supplied to customers monthly. This arrangement has the advantage of combining objective statistical analysis with the interpretive skills of a service team familiar with the customer’s unique challenges.

TOMRA Insight’s data-gathering helps mineral processors in near real-time and in retrospect. Machine operators are empowered to take prompt action in response to changes in material composition on the line and managers are empowered to make operational and business decisions based on more complete information. Comparisons between multiple sites or lines can now be made more accurately and difficult-to-reach processing operations can be remotely monitored from more convenient locations. This functionality is especially useful now that COVID 19 has brought widespread travel restrictions.

One early, pre-launch user of TOMRA Insight is the Black Chrome Mine in South Africa (Figure 1), one of two mining projects that form the basis of the Sail Group’s plans for long-term sustainable chrome production. Since TOMRA Insight was connected to sorting machines here at the start of 2020, the data platform has convincingly proven its effectiveness. Among the gains made so far – some of which are necessarily confidential – there have been improvements in process monitoring and streamlining, more efficient line-feeding and machine running times, and reduced downtime.

Albert du Preez, Senior Vice President and Head of TOMRA Mining, commented: “By accessing information, TOMRA Insight is unlocking new opportunities. Mineral processors can now move from making decisions based on experience and local observations to decisions based on experience and hard facts. This means TOMRA Insight can help reduce waste rock and downstream processing costs, enabling processors to earn more dollars per ton.”

To build on these already impressive benefits, TOMRA Mining is working closely with customers to continuously develop TOMRA Insight. The future will bring the addition of more features and functionalities, which customers will automatically receive as part of their Service Level Agreement.

Customers who do not have a Service Level Agreement can access TOMRA Insight by paid subscription. Businesses are invited to request a risk-free trial of TOMRA Insight by contacting their regional sales manager or the team directly through http://insight.tomra.com

Further Informations:
TOMRA Sorting Solutions
www.tomra.com

K+S Minerals and Agriculture, a major salt producer, turned to TOMRA Sorting Mining for a solution for the replacement of the existing sorting system at its rock salt mine in Grasleben, in Lower Saxony, Germany. The two companies have a long-standing research and development relationship, focused on exploring the application of TOMRA’s technologies to salt sorting.

K+S Minerals and Agriculture operates in a sector that is recording a growing trend. According to the “Global salt market size 2019-2025” report published by market and consumer data provider Statista, the global salt market was valued at about 28 bn US$ in 2019 and is forecast to exceed 32 bn US$ by 2025. The industry growth is driven by a rise in the demand for salt applied in the chemical manufacturing industry – especially in chlorine-alkali chemicals production.

The challenges of rock salt sorting at the Grasleben mine

At the Grasleben mine, rock salt is extracted from a high-quality underground deposit that stretches across two Federal States. It is processed into a wide range of products, from de-icing salt for winter road services to food-grade table salts and lick stones for livestock and domestic animals. For K+S, consistently achieving certified and guaranteed high purity, compliant with the strict standards of the food industry, is a priority.

“The sorting of rock salt is complex and demanding due to its crystalline properties. This leads to strong fluctuations in the appearance of the material”, states Sven Raabe, Technische Büro Mechanik, K+S Minerals and Agriculture.

TOMRA recommended using COLOR sorting technology: “with a customized set-up of the light sources we can detect the difference in transparency of the different particles, ensuring the high quality of the rock salt,” explains Mathilde Robben, Key Account Manager at TOMRA Mining. The team also advised installing the sorter in the underground mine as requested, so that “after an initial underground sorting stage, only the coarsely crushed rock salt undergoes further grinding and sieving above ground. Only the valuable product needs to be transported in the shaft, and the final result is high-quality, pure rock salt products in various grain sizes, which are ideal for this application. Furthermore, waste rejects can be backfilled underground, avoiding storage and emissions on the surface.”

Testing the solution at TOMRA’s Demonstration and Test Center in Wedel

TOMRA conducted a demonstration of the proposed solution at its Demonstration and Test Center in Wedel. Sven Raabe attended the test with colleagues from K+S’s technical team, Florian Lieske, Stephan Meiberg and Sven Lindner.

Seeing the technology in action was decisive: “The tests were very well prepared,” says Sven Raabe. “The on-site team quickly developed a feel for our product. The uncomplicated adaptation of the program to the different material qualities also convinced us.”

“An important factor in our purchasing decision was the positive test result achieved with the system, using transmitted light to obtain more efficient separation. This has the added benefit of resource conservation. It is possible to react quickly and individually to changing situations during dismantling. We expect this to be more effective, and the ease of use of the system was also convincing.”

The order was placed and installation completed on schedule

Following the positive experience at the Test and Demonstration Center and the results of the test, K+S placed the order for TOMRA’s solution, with installation planned for September 2020. The negotiations were conducted via video conference due to the Covid-19 travel restrictions and lockdown. The order was entered in TOMRA’s production plan and the Factory Acceptance Test was conducted on September 23^rd. The sorter was transported to the Grasleben mine, where it was placed in position underground on September 30^th and installation was completed on schedule.

“This is the first solution we provide for underground sorting, which raises specific challenges due to the dimensions and weight limitations of the mine shaft,” concludes Mathilde Robben. “In this project we also had to contend with the difficulties created by the Covid-19 pandemic. I am very pleased that we have been able to meet K+S’s requirements and deliver on schedule.”

About TOMRA Sorting Mining

TOMRA Sorting Mining designs and manufactures sensor-based sorting technologies for the global mineral processing and mining industries.

As the world market leader in sensor-based ore sorting, TOMRA is responsible for developing and engineering cutting-edge technology made to withstand harsh mining environments. TOMRA maintains its rigorous focus on quality and future-oriented thinking with technology tailor-made for mining.

Further Informations:
TOMRA Sorting Solutions
www.tomra.com

Maximizing diamond recovery while optimizing costs: this is the priority at the top of the list of every diamond producer (Figure 1). With TOMRA’s holistic approach and cutting-edge technologies, both can be achieved to deliver outstanding results. TOMRA Sorting Solutions, Wedel/Germany, is today the world’s leading supplier of X-Ray Transmission (XRT) diamond recovery technology, having recovered some of the largest and rarest gemstones in history. TOMRA’s promise to customers is simple: 100 % detection in the specified range, irrespective of luminescence profile or coating, and a guaranteed diamond recovery greater than 98 %.

TOMRA approaches every project as a partnership with the customer to deliver a complete solution that meets their operational and business requirements (Figure 2). It begins with a detailed analysis of the customer’s requirements and operational needs. Working collaboratively, it assists in developing a tailor-made flow sheet 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. 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.

Once the system is fully operational, TOMRA remains at the customer’s side through its Service Level Agreement, unique on the market, to ensure the solution continues to deliver the desired results. The tailored agreement can include on-site presence as required, seven days/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.

TOMRA’s XRT technology recognizes 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’s XRT high-capacity sorters are incredibly effective in the recovery of free, liberated diamonds at high feed rates up to 300 t/h.

TOMRA’s NIR sorters recognize and separate Kimberlite and waste rock based on their chemical composition. This technology is useful in upgrading lower grade ROM and stockpiles, producing a Kimberlite concentrate for further processing.

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 leading Canadian 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.”

With its customized approach, TOMRA 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. High waste dilution impacts the crushing energy needed and further increases diamond breakage risk. Utilizing 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 ton 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 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 become economically viable. 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. 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. 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 up to 1,100 ct – and where it has recovered Angola’s second-biggest diamond on record in 2017, a 227 ct stone. “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,” commented Stephen Wetherall, Lucapa Diamonds Managing Director at the time of the recovery.

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.

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.

TOMRA’s solution eliminates up to seven concentration stages, dramatically reducing the complexity of the supporting plant and infrastructure. 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 that there is no manual handling during pre-concentration and recovery, which has positive implications on security and eliminates human error resulting in greater accuracy.

TOMRA’s sorters not only stand out for their high capacity, they process these large volumes with great efficiency, finding more diamonds than other, traditional separation methods – including coated and low- or non-luminescent diamonds. 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 of > 98 %

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 to traditional recovery methods such as DMS and XRL. In addition, the economic recovery of Ultra Low-Frequency Exceptional Diamonds of + 32 mm is now possible.

TOMRA’s XRT technology has exceeded all expectations at Lucara Diamond Corporation’s Karowe mine in Botswana with a string of record-breaking diamond recoveries. TOMRA’s Large Diamond Recovery circuit was installed in 2015 and Eira Thomas, Lucara Diamond CEO is fully satisfied: “We felt, certainly, that the technology that TOMRA offered was the best. But, more importantly, I think it was really around the approach, the attitude of collaboration and willingness to actually work with Lucara as we undertook to solve this problem.”

Further information:
TOMRA Sorting Solutions
www.tomra.com

In the face of Climate Change, the calls for a sustainable growth agenda are increasingly urgent. Last March the European Commission announced its Circular Economy Action Plan as one of the main blocks of the European Green Deal. This new EU action plan promotes the idea of a circular economy and fosters sustainable processes along the entire life cycle of products, aiming to ensure that the resources used remain in use for as long as possible. The plan focuses on the sectors that use most resources and where the potential for circularity is high, many of which rely on the mining industry for their raw materials.

Mining will play a vital role, as primary resources will continue to be needed due to the growing population and rising per capita consumption, and because it is impossible to close the loop. The development of a circular economy in mining presents both challenges and opportunities for mining companies. It has the potential to address the shortage of mineral resources, waste of resources and environmental pollution while generating economic benefits.

The circular-economy approach prioritizes reusing materials over extracting new raw materials. However, the need for virgin materials remains, and wherever they are used, their footprint should be as small as possible. Also, companies in all industries are under pressure to reduce their environmental impact. This will drive an increase in the demand for sustainably mined products, which poses a challenge for mining companies, but also opens new opportunities.

In order to reduce the footprint of the products they offer, mining companies will need to find ways to maximize the efficiency of their operations to minimize the use of energy and other inputs, while reducing waste as much as possible.

By investing in new technologies such as sensor-based sorting from TOMRA Sorting Solutions, Wedel/Germany, mining companies can take new approaches to extract natural commodities in an energy-efficient and resource-conserving manner.

Installing ore sorting machinery in the early stages of the process has the potential to increase productivity through greater efficiency, as Fred Earnest, President and CEO of Vista Gold Corporation, has experienced with a TOMRA XRT sorter: “Because we’re processing less material, we’re now able to do a finer size. With finer grind our gold recovery has gone up. This has resulted in improvements of grade by 10 %; our feed grade to the mill has gone up from 0.84 g/t to now 0.91 g/t. We’ve been able to achieve all of this on a capital-neutral basis.”

Sensor-based sorting technology can also significantly increase efficiency in terms of the input resources, such as energy, water and process reagents per ton of product. This significantly reduces the environmental footprint of the operation. Also, in an environment where competition for resources with other stakeholders such as communities and agriculture is increasingly fierce, this can become a driver to obtain the Social Licence to Operate.

Grinding is the most energy-intensive part of the production process, and sensor-based sorting has been proven to reduce energy consumption by about half, with a consequent cut in CO₂ emissions. It also results in a smaller footprint for the operation and reduces waste material.

TOMRA’s sensor-based ore sorting can contribute to circular economy practices at the mine site level through a proactive management of mining waste dumps and by extending the lifetime of their operation. This technology can recover valuable ore even from sub-economic deposits or dumps, turning marginal waste into value, adding to its significant impact on the sustainability and profitability of the mine.

This was the experience of the engineering and project management company P2E Consulting, which commissioned a TOMRA X-Ray Transmission sorter to replace an existing drum Dense Media Separation (DMS) plant at Eastern Chrome mines in South Africa (Figure 1). “The TOMRA XRT sorter is used to upgrade Under Value (UV) material with a head grade of 20 to 28 %, to produce a saleable product at a minimum grade of 38 % Cr₂O₃. It does this efficiently and at a low Cost of Production (COP), with achieving grades in excess of 40 % Cr₂O₃ and mass recoveries of 25 to 30 % from scalped waste resulting in Chrome-in-tails as low as 12 %. There was no water usage at all and we didn’t need to spend on expensive reagents, so that we are producing small lumpy product for approximately 50 % of the cost compared to a DMS plant.”

Further information:
TOMRA Sorting Mining
www.tomra.com/mining

TOMRA Sorting Mining has developed virtual testing capabilities to help mining operations ensure their business and operational continuity, enabling them to take informed purchasing decisions for their sorting plants. This is the latest action in the company’s plan to provide its customers all the support they need in the current situation and take their business forward.

Ensuring business continuity at this time is of paramount importance for mining operations. 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 them identify the best sorting solution for their mine by offering them remote access to its Test Center in Wedel, Germany, which has capabilities for all applications.

TOMRA’s temporary Virtual Demonstration and Test Solution will enable mining companies to test the sorting solutions on their samples without leaving their office. 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 it is completed, they will receive a video of their material being sorted and discuss the results with a TOMRA’s sales person and the Test Center’s experts via video call. With their support, they will be able to make a decision on the following steps and take the project forward without delay.

Albert du Preez, SVP and Head of TOMRA Sorting Mining, explains: “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 Centers 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 flow sheet 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 Centers play a key role in the company’s collaborative approach to supporting customers with their ore sorting requirements. 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 is able to proceed with their investment with confidence.

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. 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 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 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 X-Ray Transmission system installed as a result of this visit to the Test Center.

The development of this Virtual and Demonstration and Test Solution is the latest action in TOMRA Mining’s plan to ensure it provides customers all the support they need in the current situation. It has increased stocks of critical components to ensure its ability to fulfill current and future orders, and to ensure the supply of spare parts without disruption. The company is leveraging digital technology not only to take the expertise of its Test Centers to customers, but also by using its remote service and training tools to support their equipment while respecting social distancing safety measures.

Further informations:
TOMRA Sorting Mining
www.tomra.com/mining

The quartz market has witnessed a steady growth, and this trend is expected to continue. Analysts are forecasting a compound annual growth rate of over 4.5% in the next five years, driven by the increasing demand from the electronics industry. This is mainly due to the more widespread use and increase in production of electronic devices in developing countries, including China, India, Thailand and Vietnam.

The metallurgical industry is consequently a key market for quartz: it is the best source of silicon metal and polysilicon, the semiconductor at the heart of electronics, which is also used for other products, such as photovoltaic cells. Another important market is engineered stone, for uses such as kitchen countertops or tiles. Silicon also has a vast range of uses in very different sectors, from the chemical and cosmetics industries to automotive applications, as well as in the production of quartz sand for livestock farming or golf courses, or for specialised applications such as artificial turf.

Quartz is one of the most common minerals, found in all forms of rock, but it doesn’t exist in high purity in nature: the challenge for mining operations serving the metallurgical and engineered stone industries is to reliably deliver quartz of consistently high chemical purity – and for engineered stone manufacturers, a white product with no impurities of the same color, such as feldspar, is also essential.TOMRA’s patented multi-channel Laser sorting technology unlocks the full potential of quartz deposits with its structural approach to sorting, unique in the market. The scattering effect of the multiple laser beams can be used to separate a quartz rock from a similar-looking one containing no quartz: quartz or quartz veins will appear as a glowing crystals because quartz returns the laser light in a larger area, while others will remain dark with no visible scattering. Large and pure crystals can be clearly discriminated from other rocks or minerals with a smaller crystal structure, regardless of the color or chemical composition. TOMRA’s Laser sorter also stands out for being a gravity system rather than the conventional conveyor belt, so that both sides of the material are scanned and multiple characteristics such as surface structure, size, shape, brightness and color distribution are processed simultaneously. Laboratory tests and field experience have shown that the recovery of valuable rocks can be increased by 20% while improving the quality of the product.

Jens-Michael Bergmann, Industrial Mineral Segment Manager at TOMRA Sorting Mining, explains: “The advantages for mine operations are multiple, from a longer life of the mine to lower operating costs and a reduction of waste, with consequent lower haulage costs. It also enables them to guarantee consistent high-quality of product to their customers.”

TOMRA’s Laser sorting technology also has environmental benefits, due to the reduced waste and low water use, as only a small quantity is required for wet washing the rocks at the beginning of the process to avoid dust in the processing plant. It eliminates the need for hand picking, which is required with color sorting in order to achieve the high purity levels demanded by the metallurgy and engineered stone industries. This has a positive impact on the mining operation’s Health and Safety, as it means there is no exposure to silicon dust in the sorting process.

High purity ensured for metallurgical quartz production at Erimsa

Spanish company Erimsa is part of Elkem AS, one of the world’s leading suppliers of silicon-based advanced materials. The company has over 30 years’ experience in quartz extraction using an environmentally friendly method that enables it to generate wealth sustainably in the communities where it operates. It specializes in the production of aggregates for the construction industry and metallurgical quartz, which means that a consistently high chemical purity of the quartz is paramount. Originally, it achieved this level of quality through manual sorting. Carlos Forján, Quality Manager at Erimsa explains: “Traditionally, the material was sorted manually by many operators. It was very boring and exhausting work, which resulted in low efficiency and many errors, making it difficult to predict the quality of the output with reliability.”

In 2000, the company introduced Color sorting technology. However, in order to achieve the high level of purity they required, the sorters were calibrated in a way that resulted in high rejection rates of material containing quartz. This meant that hand picking was still required in order to improve the recovery and ensure the stability in the quality of the quartz that is key for Erimsa. Carlos Forján turned to TOMRA for its Laser technology, which he thought would enable them to sort good quality quartz regardless of the color: “The main problem we have is in the complexity of sorting automatically when the quartz and the rejectable minerals have the same color. I thought that Laser technology would be the way to address this.”

In 2016, following tests conducted at TOMRA’s Center in Wedel, Germany, a PRO Secondary LASER Dual sorting machine was installed at its processing plant in Salamanca. The quartz is extracted and washed to avoid dust in the plant, then it is screened by size. Materials over 70 mm are hand-picked by four operators; materials under 20 mm are shipped to aggregates and quartz sand customers; materials between 20 and 70 mm are fed to the TOMRA multi-channel Laser machine, which sorts out the waste material. A final quality check is conducted by 2 operators to remove the rare pieces with quartz content that may have been ejected in the waste by the sorter, as it is calibrated to maximize recovery.

Carlos Forján had high expectations for the TOMRA Multi-channel Laser sorter, and he is fully satisfied: “The TOMRA machine has enabled us to reduce costs while increasing our yield; our production has easily increased by 20% compared to when we used Color sorters combined with hand picking. Material that in the past was lost to the waste pile is now generating profit for us. The stability of the quality is an important goal, and we have achieved this with the Laser sorter. It has been such a game-changer in our operation, that we are planning the purchase of a second Laser machine to replace an existing Color sorter.”

TOMRA’s collaborative approach and out-of-the-box thinking have been very important for Carlos Forján: “The high level of knowledge of TOMRA’s technicians and their attitude towards finding solutions for any issue that arose were invaluable. I would say that the TOMRA service is world-class, because they are able to deliver solutions for the unpredictable issues that are in the nature of the mining activity.”

TOMRA Color and Laser sorters in combination to sort by color, composition and size

Companies that serve different industries need the most precise mineral sorting in order to meet their customers’ requirements specific to each sector. This is the case of Mikroman Mining Company, which uses a combination of TOMRA Laser and TOMRA Color sorters to differentiate products according to four qualities: white and light grey quartz with low iron oxide content for engineered stones; grey and yellow quartz for the glass industry; colored quartz for ferrosilicon used in the metallurgical sector; and colored gravel, also for ferrosilicon, which currently goes with the waste.

These precise distinctions, resulting in higher product quality, were not possible before the acquisition of the TOMRA machines, and today the company operates 13 Color sorters and 3 Laser sorters in its various plants.

Further informations:
TOMRA Sorting Mining
www.tomra.com/mining

Lucara Diamond Corporation owns the Karowe diamond mine in Botswana, which has been in production since 2012. The mine is recognised as one of the foremost producers of very large, high-quality Type IIA diamonds in excess of 10.8 ct. Historic recoveries include the 1,109 ct Lesedi La Rona – the second-largest gem quality diamond ever found – and the 813 ct Constellation diamond. Lucara’s success at the Karowe mine continues, most recently with rare gem quality blue and pink diamonds recovered in September 2019.

Initial work on the mine was carried out by previous owners in the 1970s with the technology available at the time, which had its limitations. “What we realised in looking at the diamonds that resulted from that work is that many of them were actually broken,” explains Eira Thomas, CEO of Lucara. “When production started, it became apparent that the diamond population was quite coarse, and that necessitated a re-think on how we could adjust or optimise flow sheet focused on diamond value preservation. That was our real focus and goal in starting the conversation with TOMRA, about how can we do this better, how can we actually get diamonds out of our mineralized ore in a more efficient way and in a way that actually maximizes the value of those diamonds and minimizes the damage of those goods.”

The AK6 Kimberlite found in the Karowe presents a difficult challenge, as John Armstrong, Vice President, Technical Services for Lucara explains: “It has a very high Dense Media Separation yield, in that up to 10 to 15 % of the material that would go into the plant would report as a heavy-metal concentrate, making it a very difficult ore body to process in a traditional diamond processing scenario. We undertook a series of testing campaigns and investigations to explore alternative technologies. We elected to go with TOMRA as our partner in moving forward in getting this technology to the mine into part of the circuit that hadn’t been envisioned previously.”

The solution of TOMRA Sorting Mining, Langenfeld/Germany, delivered very quickly, exceeding all expectations (Figure 1): “When we put in the large diamond recovery circuit in 2015, it was within two weeks of making this investment, which was somewhere around 30 to 35 M US$, that we recovered those two exceptionally large diamonds, so in this case it was under two weeks we’d already had two times our return on that investment,” says Thomas.

The Lucara project clearly shows that TOMRA stands out not only for its industry-leading technology but, very importantly, for its extensive know-how and approach to working with customers, which it views as a true business partnership.

Thomas explains the reasons for their choice of working with TOMRA: “We felt, certainly, that the technology that -TOMRA offered was the best. But, more importantly, I think it was really around the approach, the attitude of collaboration and willingness to actually work with Lucara as we undertook to solve this problem, and that to us was a very appealing element because we weren’t entirely certain what the solution was going to be, we just felt that by working with a team of experts that understood the problem and had technology that could help us, we could together come up with a solution that made sense. And I think that was the big opportunity for us as we sought in working with TOMRA.”

Armstrong agrees: “As part of the process that made working with TOMRA unique and special was their willingness to view the relationship between Lucara and TOMRA as a partnership, and we were both investing in this, and we were both going to learn a lot from it, and we relied on each other to ensure that we were going to be successful.”

“I think the Lesedi and The Constellation recoveries really did open up a lot of eyes, and I think it opened a lot of minds to the idea that technology can and will make a big difference to not only existing diamond mining operations, but future mining opportunities and it’s a great testament to the efforts that we’ve made in collaboration with TOMRA to really get out and tell the story,” comments Thomas.

Further information:
TOMRA Sorting Mining
www.tomra.com/mining

MINSUR SA is a Peruvian mining company, part of the Breca Group of Companies, that owns and runs the largest underground tin mining operation in the world. Located in San Rafael (Figure 1), in the Eastern Mountain chain of the Andes in Peru at a high altitude between 4,500 to 5,200 m above sea level, the mine contributed about 6 % of the total world production of tin in 2015, when about 1 Mt of ore with an average grade of 2.13 % were mined and processed, resulting in 20 kt of tin in concentrate. The same year, ­MINSUR initiated a number of activities to ensure the future value of its asset, addressing challenges that included declining head grades through depletion of rich parts of the deposit and operating costs.

Among these activities was the ore sorting project, started in 2015 in collaboration with TOMRA Sorting Mining, Wedel/Germany, with the objective of rejecting low grade material in coarse particle size. By separating sub-economic material before entering the more cost-intensive wet processing, the project would address the bottleneck at the wet section and improve productivity by increasing the feed grade. An added benefit expected from the project would be the longer life of the mine.

Three main factors indicated that sensor-based particle sorting for waste rejection would be effective at the San Rafael mine. First of all, the high absorption of transmitting X-Rays of tin contained in Cassiterite; second, the structures of Cassiterite which are large enough to be detected by X-Ray Transmission (XRT) technology due to the way its mineralization occurs; finally, the significant degree of liberation of sub-economic waste on the particle level that may be subject to sensor-based particle sorting.

In order to assess the feasibility of the project, TOMRA conducted metallurgical tests on geological samples from San Rafael, followed by Performance Test Work. The tests showed the deposit of the mine to be especially suited for XRT technology due to the presence of 70 to 80 % of uneconomic particles that can be rejected over a wide size range, from 6 to 70 mm.

The project was approved and, in view of the significant economic potential, it was fast tracked and completed in just 14 months. TOMRA and its partner in Peru, which supplied and installed the XRT sorting system, worked closely with MINSUR throughout the six-month ramp up period.

Fig. 3. TOMRA’s sensor-based ore sorting system at San Rafael tin mine. // Bild 3. Sensorgestütztes Erzsortiersystem von TOMRA in der San Rafael Zinnmine. Photo/Foto: TOMRAThe ore sorting project with TOMRA’s XRT system has delivered significant financial benefits from the beginning, with MINSUR realizing payback on their total capital expenditure in just four months. In 2017, it contributed around 36 % of MINSUR’s total production with about 6,000 t of tin.

The project’s impact on the San Rafael operation is contributing in several ways to a reduction in the mine’s capital and operating costs:

• Added value: TOMRA’s XRT sensor-based ore sorting is converting uneconomic waste material into economic ore, as material below the cut-off for the main plant can be treated with lower operating costs and converted into reserves.
• Increased capacity in the main plant, from 2,950 t/d before implementation to today’s 3,200 t/d, as a result of the crushing operation at the XRT-sorting plant.
• Significant improvement in the overall recovery in the main plant, from 90.5 to 92.5 %. This is because sensor-based ore sorting rejects particles with very fine mineralized Cassiterite that is too small for detection by the XRT system, resulting in higher grade and size of mineralization.
• Extended life-of-mine: Today, about 24 % of the feed to the sensor-based ore sorting plant is contributed by low grade ore from underground, which in the past would have been excluded for being below cut-off. This increase in reserves significantly extends the life-of-mine.
• Elimination of liabilities through the treatment and proper disposal of 100 % of the stockpile.
• Decreased tailings disposal, as the sensor-based ore sorting system reduces the amount of waste by increasing the grade in the feed to the plant.

The success of the project has demonstrated the high potential of TOMRA’s XRT technology, and as a result the company plans to include XRT sensor-based ore sorting as a possible process route in all future projects.

Further information:
TOMRA Sorting Mining
www.tomra.com/mining

Vista Gold Corporation owns the Mt. Todd project in Australia, which was acquired in 2006 and is one of the country’s biggest undeveloped gold resource. The project, briefly operated in the 1990s, is known for having hard ore (Figure 1). This, and the fact that the project was operated previously, presented particular challenges for Vista Gold.

“We had a desire to find a way to only be spending money to process the rock that had gold in it,” explains Fred Earnest, President and CEO of Vista Gold. “We started looking for ways that we could get rid of the non-mineralised host rock prior to the grinding circuit. The company looked at different technologies to address the issues at the Mt. Todd project and contacted TOMRA Sorting Mining to find out about its sensor-based sorting technology.”

TOMRA Sorting Mining, Langenfeld/Germany, invited the Vista Gold team to visit their testing facility in Germany with a sample from the project to see first-hand what could be achieved. The test was an eye opener for Earnest.

Following extensive testing, Vista Gold has integrated TOMRA’s two-stage sorting solution in its flow sheet at Mt. Todd. The system sorts 20 t/h, using X-Ray Transmission (XRT) technology to remove particles containing sulphide minerals and subsequently lasers to remove particles containing quartz and calcite.

The benefits of TOMRA’s solution to the Mt. Todd project are two-fold. On the one hand, operating costs have been reduced: “We’re getting rid of material and we’re not spending money grinding rock that has no value,” explains Earnest. On the other hand, gold recovery has improved: “We’ve been able to make design changes in the plant. Because we’re processing less material, we’re now able to do a finer size. With finer grind our gold recovery has gone up. This has resulted in improvements of grade by 10 %. Our feed grade to the mill has gone up from 0.84 g/t to now 0.91 g/t.”

What’s more, the savings in operating costs have paid for the improvements to the plant: “We’ve been able to achieve all of this on a capital-neutral basis. We’ve been able to incorporate the equipment for the sorting to add fine grinding equipment, all with the money that we’ve saved from the ball mills. And so, ore sorting has opened up a whole new window of opportunity for us with the Mt. Todd project. We’re very excited about what this technology means to the mining industry and specifically to our projects in the future. And we look forward to seeing this technology grow and become even more efficient and of greater value to us,” concludes Earnest.

TOMRA worked closely with Vista Gold’s team to identify the best solution for the Mt. Todd project – from testing rock from the mine at its facility in Germany, to analysing the situation at the project and advising on how its sensor-based sorting technology could fit in their operation to deliver the best results.

Further information:
TOMRA Sorting Mining
www.tomra.com/mining

Stornoway Diamonds is a leading Canadian diamond exploration and producing company. It owns and operates the Renard Mine (Figure 1), in commercial production operation since 2017. It is the first diamond mine in Québec and one of six in Canada. Renard Mine started with an open-pit mine and subsequently opened an underground mine.

The conditions of the mine presented Stornoway Diamonds with particular challenges that required an innovative approach: “Due to the geology of our ore, meaning we produce very high yield, we have lots of material that we need to sort through. At times, we have the possibility of losing some of those very expensive diamonds due to inefficiencies,” explains Marie-Claude Hallé, Marketing Operations Manager for Stornoway Diamonds. In addition, “our ore body at the Renard mine contains a high level of internal and external dilution called country rock, a significant issue for us, as it can make up to 30 to 40 % of the feed to the plant. With that come very high energy costs from crushing all this waste material that is not diamond bearing. It causes a tremendous amount of wear and tear on our equipment from screening conveyors, diamond recovery equipment, and on a dollar-per-tonne basis we spend a lot of money processing non-diamond bearing material.”

Stornoway Diamonds needed to find a way to reduce its costs and optimise its operation, and they are fully satisfied with the solution provided by TOMRA Sorting Mining, Langenfeld/Germany: “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,” states Hallé.

TOMRA analyzed the situation and worked closely with Stornoway Diamond’s team to design and install a Kimberlite pre-concentration plant. The specific conditions at the Renard mine meant that the traditional Dense Media Separation method could not provide an efficient and cost-effective solution. It required innovative approach, which TOMRA delivered, making Renard the first diamond mine to incorporate ore sorting into its processing plant.

TOMRA addressed the mine’s recovery issue with its industry-leading sorting technologies, developing a solution with four key objectives for the ore sorting plant: minimize diamond breakage by removing hard rocks from the crushing plant feed; upgrade the quality of the material to the process plant by increasing the proportion of Kimberlite to waste rock; reduce the energy required for crushing by removing the harder rocks; and improve circuit efficiencies throughout the plant.

TOMRA’s solution features five PRO Near Infrared (NIR) sorters in its ore sorting circuit. This technology is particularly well suited to enable discrimination between the various ore and waste materials that need separation at the Renard mine, based on their different chemical composition.

TOMRA also included in a COM XRT 2400 sorter, which uses X-Ray Transmission (XRT) technology to separate material according to its specific atomic density, in the plant’s large diamond recovery circuit.

“The TOMRA solution we have in operation has offered us a very low-cost, efficient reliable means of recovering our coarse diamonds without inefficiency, without causing diamond breakage,” comments Hallé. “It’s a very neat way to get those diamonds out of the Kimberlite at the very early stage of the process. We reduce our power consumption cost, we reduce our wear and tear on material. We are still optimising this unit, and we feel there are even more benefits to come in terms of how it helps enhancing the overall recovery of our diamonds.”

Geoffrey Madderson, Diamond Segment Manager at TOMRA concludes: “The implementation of this plant proves that TOMRA waste sorting technology can successfully be used to upgrade lower grade ROM and that Sensor-based Sorting can be used to further improve value recovery for our clients on lower-grade resources.”

The integration of the ore sorting plant into the main processing plant was completed smoothly, with TOMRA’s full involvement in the ore sorting plant design. TOMRA also had a team onsite for the first three months of operation to ensure a seamless transition, and will continue to provide ongoing support for the entire life of the equipment.

Further information:
TOMRA Sorting Mining
www.tomra.com/mining