Tag Archives: quartz

TOMRA laser-based ore sorter helps open new markets for quartz miner Mikroman

Mine operation news, Mineral processing, Mining equipment, Precious metals, , , ,

Turkish Quartz mining company Mikroman Maden A.Ş is leveraging TOMRA’s laser-based ore sorting solution to process the finer materials at its operations and turn them into value, the sorting company says.

Mikroman first adopted sensor-based sorting technology at three of its processing plants in 2018, installing three high-capacity TOMRA PRO Secondary LASER sorters, in the process, reaching its target of improving product quality and increasing capacity at these facilities.

At its Kula plant in Manisa province, which requires the most precise mineral sorting, it combined TOMRA’s COLOR and LASER technologies to achieve the best results and recovery with the highest purity levels, as well as creating products of differing quality to meet the specific needs of a variety of markets, TOMRA says.

Satisfied with the results achieved at the Kula plant by using sorters on bigger particle sizes, Mikroman asked TOMRA for a solution to process the finer materials and turn them into value.

Mikroman was processing particles sizes down to 15 mm with a PRO Tertiary COLOR, and TOMRA installed three additional PRO Tertiary COLOR sorters for finer particles: two for sorting particle sizes from 2-4 mm and one for sizes from 4-10 mm to remove coloured impurities from the material, which is then processed further in a micronised plant on the premises.

These sorters offer increased product flexibility for the company, according to TOMRA.

Mikroman also wanted to achieve the high purity levels achieved with laser technology in grain sizes below 20 mm, but, at the time, the PRO Tertiary was only available with COLOR technology, according to Ines Hartwig, Director Product Management at TOMRA Mining.

TOMRA looked into the development of a new product implementing the TOMRA multi-channel LASER technology in the PRO Tertiary platform, she said.

“With this solution, also white non-quartz impurities like shist, feldspar, shale and calcite can be detected and sorted out to achieve a pure white, high-grade quartz product,” Hartwig said.

TOMRA developed and tested extensively the new PRO Tertiary LASER sorter (pictured below) in close collaboration with Mikroman.

Serhat Saran, Chairman of the Board of Directors and General Manager of Mikroman, remarked: “We worked as if TOMRA’s Research and Development department was one with our own.”

Serhat Saran, Chairman of the Board of Directors and General Manager of Mikroman

Hartwig added: “As Mikroman had already implemented the LASER technology for bigger grain sizes and had experienced its advantages compared to COLOR sorters, it was a perfect fit to collaborate, design and field test this new product. They provided us with the small particle references of product and waste that they expected to sort and our engineering team developed the new machine with the support of Markus Dehler, Manager of the TOMRA Mining Test Center.”

The resultant PRO Tertiary LASER sorter uses the same multi-channel LASER technology as the PRO Secondary platform, but is specialised in detecting and sorting smaller sized material, from 6-32 mm, according to TOMRA. The distance between detection and ejection is minimised and the number of ejectors increased to result in a very precise, effective and efficient sorting and highest product quality and yield.

“The TOMRA PRO Tertiary LASER is a low-maintenance, simple and stable platform that has the advantage of being the only one on the market to offer customisation of the laser wavelengths to match the specific application,” TOMRA said. “The development was completed in a short timeframe and a new PRO Tertiary LASER sorter was installed at the Kula plant to process grain sizes 5-15 mm and 15-35 mm.”

The two PRO Tertiary COLOR and LASER sorters combined are consistently removing 98% of impurities in small sizes from 5-35 mm, while delivering savings in water, fuel and electricity consumption in the downstream process, according to TOMRA.

With these investments, Mikroman has expanded its capacity and product portfolio to serve a wide range of industries – composite stone, glass, electronics, metallurgy, paint and ceramics, among others – and exports to 15 countries including the US, Spain, Italy and Israel.

“The ability to sort all the size ranges offered by TOMRA according to the colour and chemistry of the product has allowed us to become the leading company in the sector, and to hold a large share of 65% of the exports around the world and domestic sales in Turkey,” Saran said.

The collaboration with TOMRA has developed as Mikroman’s operation evolved, with the addition of further COLOR and LASER sorters, which now total 18 units across four plants. This includes 10 TOMRA sorters at the Yava and Kula plants, one in its Karpuzlu mine in the Aydin province and two sorters at the new Catalca plant in Istanbul. It has also ordered two additional PRO Tertiary COLOR sorters and a PRO Tertiary LASER, which have been delivered and will soon be installed at the Kula plant.

TOMRA continues to build ore sorting Insight across mining space

Bulk handling, Diamond mining, Industrial minerals, Mineral processing, Mining services, Precious metals, , , , , , , , , , , , , , , ,

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

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

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

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

TOMRA’s Harold Cline & Jordan Rutledge

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

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

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

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

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

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

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

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

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

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

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

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

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

Piedmont looks at IPCC, Metso Outotec alkaline pressure leach for lithium project

Energy minerals, Environmental, Mineral processing, Mineral project development, , , , , , , , , , , , ,

Piedmont Lithium’s plan to build out an integrated lithium hydroxide business from a base in North Carolina, USA, has advanced with the release of a scoping study that, it says, confirms that Carolina Lithium will be one of the world’s largest and lowest-cost producers of lithium hydroxide with a “superior” sustainability footprint.

Piedmont Carolina Lithium contemplates a single, integrated site, comprising quarrying, spodumene concentration, by-products processing, and spodumene conversion to lithium hydroxide at its site in Gaston County. There are currently no such integrated sites operating anywhere in the world, with the company saying the economic and environmental advantages of this strategy are compelling.

The latest study outlined a production target of around 4.96 Mt of 6% Li2O spodumene concentrate (SC6), averaging approximately 248,000 t/y of SC6 over the 20-year mine life. This equates to an average of 1.95 Mt/y of ore processed, totalling some 37.4 Mt of run-of-mine ore at an average grade of 1.09% Li2O (undiluted) over the 20-year mine life.

Of the total production target of 4.96 Mt of SC6, some 1.19 Mt will be sold to third parties during the operational life and approximately 3.77 Mt will be supplied to Piedmont’s chemical plant operations for conversion into lithium hydroxide. This results in a total production target of about 582,000 t of lithium hydroxide, averaging approximately 29,095 t/y of lithium hydroxide over 20 years, the company said. The study also assumes production targets of 4.83 Mt of quartz concentrate, 7.51 Mt of feldspar concentrate, and 1.34 Mt of mica concentrate over the life of operations.

Piedmont envisages a total initial capital cost of $838.6 million for the project and an after-tax net present value (8% discount) of $1.92 billion.

While still very much preliminary, the flowsheet and mining process for this planned operation is of interest to any lithium developer looking for a ‘sustainable’ mining footprint.

The company currently envisages using a Metso Outotec alkaline pressure leach process as part of its plan. This will reduce emissions, eliminate sulphuric acid roasting and reduce solid waste, it said.

At the same time, in-pit crushing and conveyor systems are on the agenda, eliminating mining trucks in the study to reduce fossil fuel consumption.

Piedmont has also been working with a solar developer to build and operate a solar farm on Piedmont property capable of producing electricity to supply up to 100% of Piedmont needs.

The company will also co-locate all operations on the same proposed site in Gaston County to minimise any transit and allow unused by-product streams to be repurposed for site redevelopment, it said. This adds up, Piedmont says, to highly efficient land and water use compared with South American lithium brine production.

Keith D Phillips, President and Chief Executive Officer of Piedmont, said: “We are exceedingly pleased with the results of our updated scoping study. The economics of our project continue to impress, but I am particularly proud of the project’s sustainability profile.

“As we move forward to complete a definitive feasibility study for Carolina Lithium later in 2021, Piedmont has engaged Evercore and JPMorgan as financial advisors to evaluate potential strategic partnering and financing options for its North Carolina project. Given the project’s unique position as the only American spodumene project, with world-class scale, economics, and sustainability, we expect strategic interest to be robust.

COREM, Steinert ore sorting tests present opportunities for Cartier at Chimo gold project

Environmental, Mineral processing, Mineral project development, Mining equipment, Mining services, Precious metals, , , , , , , , , ,

Cartier Resources says ore sorting tests carried out by COREM and Steinert US on mineralised samples from the Chimo Mine property, in Quebec, Canada, have indicated gold grades could increase substantially with the use of the pre-concentration technology.

Gold from Chimo is present in two types of mineralised facies: i) quartz veins with coarse visible gold grains having an affinity for the gravity concentration of gold at the mill and ii) zones of silica-rich mafic rocks associated with non-refractory arsenopyrite having an affinity for the flotation of a concentrate of arsenopyrite for gold recovery at the mill.

To perform the sorting tests, rocks representative of the two mineralised facies, made up of the following six mineralogical facies, were first selected for static recognition of each of the facies by the sensors of the sorter:

  • Gold-bearing quartz veins;
  • Gold-bearing silica;
  • High grade gold-bearing arsenopyrite;
  • Medium grade gold-bearing arsenopyrite;
  • Low grade gold-bearing arsenopyrite; and
  • Mafic waste rock.

The detection sensors of the industrial sorter at COREM in Quebec, Canada, were the RGB camera using the optical properties of reflection, brightness and transparency to locate quartz and silica and the X-ray Transmission sensor using the volumetric property of atomic density to locate arsenopyrite. The two sensors adequately recognised the six mineralogical facies associated with the mineralisation, with dynamic calibration tests of the sorter with the moving conveyor making it possible to sort, one at a time, 2 kg samples of each of the facies, Cartier said.

The results of this first test at COREM showed the first three sorts (on a total of eight sorts) concentrated 99.1% of the gold contained in 44.4% by mass of material mass for a grade of 56.3 g/t Au, representing a percentage increase of 223% in gold content over sorter feed. The reject, representing 0.9% by mass of material, contained only 0.4 g/t Au.

The sorter was then ready to perform sorting tests on the 105.7 kg production sample, representative of the mineralised facies at an average grade of 2.16 g/t Au. This content was obtained by including 20% by mass of material with zero grade of gold, simulating dilution in the stopes. COREM’s sorting plan separated 53.9% by mass of the material in the form of a preconcentrate at an average grade of 3.68 g/t Au, representing an increase of 170% in the gold grade compared with the sorter feed. The waste disposal, separated from the mineralisation, represented 46.1% by mass of material at an average grade of 0.38 g/t Au.

Sorting tests carried out with Steinert in Kentucky using a Steinert KSS FLI XT machine with XRT, colour, laser, and induction sensors yielded comparable results.

A 80.69 kg production sample, representative of the mineralised facies at an average grade of 2.13 g/t Au, to which 20% by mass of material at zero grade of gold was added mathematically, representing the dilution in the workings, was used for testing. The new calculated diluted grade was 1.55 g/t Au.

Calculation of the results revealed that 51% by mass of the dilute grade material could be separated as a preconcentrate at an average grade of 2.72 g/t Au, representing a 175% increase in gold grade compared with the sorter feed. The waste disposal, which would be separated from the mineralisation, would represent 49% by mass of material at an average grade of 0.36 g/t Au.

Sorting tests with COREM were carried out following these tests to validate that the 20% of dilution material at zero grade of gold, mathematically added, could physically be effectively separated by the sorter, Cartier said.

The sorting tests carried out by both COREM and Steinert US were comparable, with these results providing prospects for increasing the value of the resources with ore sorting technology.

The objective of the industrial sorting of the mineralisation is to increase the grade of the preconcentrated material preceding the milling operations, which allows an increase in the recovery rate at the mill, reduces transport costs to the mill, reduces milling costs, reduces the costs of environmental restoration of mine tailings, and reduces the environmental footprint of mine tailings and, consequently, increases the social acceptability of the mining project, Cartier said.

The most recent resource estimate from Chimo included 6.6 Mt at an average grade of 3.21 g/t Au for a total of 684,000 oz of gold in the indicated category and 15.2 Mt at an average grade of 2.77 g/t Au for a total of 1.36 Moz of gold in the inferred category.

Piedmont enlists Primero and Marshall Miller for lithium concentrate DFS

Comminution of minerals, Energy minerals, Mineral processing, Mineral project development, Mining services, , , , , ,

Piedmont Lithium has awarded the definitive feasibility study (DFS) of its planned spodumene concentrate operations in North Carolina, USA, to a combined team including Primero Group and Marshall Miller & Associates.

Marshall Miller is to lead quarry design activities, while Primero will advance the concentrator design, infrastructure design, and be responsible for overall study management, Piedmont said.

The study will target production of 160,000 t/y of 6% Li2O spodumene concentrate, as well as co-products including quartz and feldspar. It will include the results of the pilot test work currently ongoing at SGS Canada, which will involve “dense medium and flotation” pilot work.

Piedmont expects to complete the study on its namesake project in mid-2021 and pursue an investment decision for the concentrate operations shortly after.

At the same time, Piedmont says it is looking into developing an integrated lithium hydroxide business in North Carolina, with a planned lithium chemical plant DFS to commence in the March quarter.

Earlier in 2020, Piedmont entered a memorandum of understanding with Primero Group related to delivering the planned spodumene concentrator at the Piedmont lithium project. The two have partnered since early 2018, with Primero having been the lead engineering consultant for Piedmont’s scoping studies, concentrator design, and metallurgical test work management.

Piedmont has engaged Marshall Miller, based in Bluefield, Virginia, since 2018 to advance mine design, permitting activities, survey, geotechnical study, waste rock and tailings storage design, and other engineering support services.

Turkey’s Mikroman ups product quality, throughput with TOMRA ore sorters

Comminution of minerals, Diamond mining, Mine operation news, Mineral processing, Mining equipment, Mining services, , , , ,

Turkish quartz miner, Mikroman has been able to both improve product quality and increase capacity at its three processing plants in the country thanks to the installation of four TOMRA Sorting Solutions high-capacity sensor-based sorting systems, the technology company said.

Mikroman mines quartz from its open-pit operations in Turkey, with the company running its own mineral processing plants for crushing, washing and sorting the raw materials.

In 2018, the company installed a TOMRA PRO Secondary LASER sorting machine in two of its three plants, in Muğla and Aydin Provinces. The third plant, in Usak Province, invested in a LASER sorter plus a COLOR sorter, according to TOMRA.

TOMRA says: “In addition to being the most efficient way to sort particles, sorting machines deliver a wide range of commercial advantages to industrial mineral sorting businesses. These include a decrease in mining and haulage costs; reductions in energy and water consumption; improvements in quality and productivity; and increases in recovery.”

The company added: “Sensor-based sorters also make it possible to significantly increase the lifetime of a mining operation.”

TOMRA’s Area Sales Manager, Jens-Michael Bergmann, said TOMRA’s COLOR sorting machines employ a high-resolution camera that recognises materials based on their color. “Rocks with surficial and visible contamination are detected and sorted out, resulting in better recovery rates and higher quality than is possible with manual sorting,” he said.

“Our unique multi-channel LASER sorter delivers even greater benefits for Mikroman in achieving the highest purity levels and maximum profits. The scattering effect of multiple laser beams distinguishes a rock containing quartz from its identically coloured neighbor. Under the laser beam, a pure or non-contaminated quartz rock registers as a glow crystal, whereas similar looking rocks with no quartz content remain dark, without any visible scattering.”

Mikroman combined these two technologies for best results and recovery, according to TOMRA.

Of all three Mikroman processing plants, the one in Usak Province demands the most precise mineral sorting. Before sorting, the feed material is screened by size, with the 40-100 mm stones treated with a higher priority and stones measuring 20-40 mm in size sent down the sorting line in a separate batch. Here, the combination of a TOMRA COLOR sorter and TOMRA LASER sorter is used to differentiate products according to four predetermined qualities. These are:

  • White and light grey quartz, with low iron oxide content, for use as artificial stones (A);
  • Grey and yellow quartz, for use by the glass industry (B);
  • Coloured quartz, for ferrosilicon used by the metallurgical sector (C), and;
  • Coloured gravel (D), also for ferrosilicon, currently goes with the waste.

After crushing and washing (through a trommel screen), Mikroman’s sorting process consists of four key steps. In the first step, minerals are screened by size, with only stones measuring 40-100 mm going through to the next stage.

In the second step, the LASER machine sorts out the waste and coloured gravel from the quartz pieces at about 70 t/h capacity. In the third stage, the remaining minerals are sorted into two streams: one for colored quartz; the other for the white and light grey quartz, and the grey and yellow quartz. Finally, these two streams are hand-sorted into product types, with some further removal of remaining gravel and waste.

“These precise distinctions, resulting in higher product quality, were not possible before the acquisition of the TOMRA machines,” TOMRA said, adding that its service team worked on-site with Mikroman, as it does with all customers, to optimise the performance of the machines.

Nazmi Çetin, Mine and plant Manager at Mikroman, said: “Before having TOMRA sorters, we were worried about quality and low capacity, but now we have achieved the desired quality standard and we have seen a decrease in waste, which means productivity has increased. The system design is quite successful and the TOMRA service team are good at their job.”