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MetsoOutotec-testing

Metso Outotec on the need for holistic testing

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The Metso Outotec global network of testing, research and product development facilities covers the whole process flowsheet from comminution through separation, to filtration, refining and pyrometallurgical/hydrometallurgical processing.

It has centres all over the globe – in Australia, Brazil, Chile, Germany, Finland, Peru, USA and more – able to, the company says, offer extensive expertise and circuit simulation to a wide range of industries.

Metso Outotec’s research and testing services include evaluation of ore types, mineralogical characterisation, feed material testing, sampling, materials selection, analytical chemistry and flowsheet development.

To get a flavour of this extensive research and testing portfolio, IM spoke to Alan Boylston, Director, Process Engineering at Metso Outotec, and Rodrigo Grau, Technology Director – Minerals Processing at Metso Outotec, about the capabilities of two of the company’s facilities – York (USA) and Pori (Finland), respectively, while also touching on Metso Outotec’s global testing and research capabilities.

In 2022, the company announced a consolidation of its minerals testing services in USA into a single 5,500 sq.m facility in York able to eventually cover the full minerals value chain and support the mining industry worldwide. Pori, meanwhile, focuses on mineral technology, hydrometallurgical processes development, pyrometallurgy and ferroalloys technology and material technology. In other words, the company conducts laboratory and pilot test work, flowsheet development as well as validation and development of new technologies for the industry.

IM: Will the York facility now be seen as your ‘testing centre of excellence’?

AB: The York facility is a centre of excellence for testing, but we have many of these within the company. Our global presence, the knowledge and our expertise at each of these locations is one of the factors that sets us apart.

Each of our locations is a centre for excellence in its own field. Pori, for example, has extensive research capabilities, Sorocaba in Brazil focuses on comminution and beneficiation testing, while Lappeenranta Dewatering Technology Center concentrates on thickening and filtration. Each location is an integral part of our global testing offering. In addition to these, we have various facilities around the globe covering also aggregates and pyrometallurgical testing, research and development.

That being said, the effort we have made to expand the York Test Center gives us a much better advantage for research and testing in North America, compared to a few years ago. We can now do more pilot-scale testing, especially with equipment like our HRC™800e high pressure grinding roll (HPGR). We can also carry out pyrometallurgical testing, plus conduct magnetic separation tests. At some point in 2023, we also expect to add thickening and filtration testing to this remit. But this is a very high-level view of what we have to offer in the York location.

Metso Outotec has a global network of testing, research and product development locations

IM: Even with this consolidation in USA, are you expecting to collaborate with other global facilities when it comes to testing processes throughout the flowsheet?

AB: Yes, absolutely. For example, we have a project coming in right now where the sample was first in Tampere (Finland) for some crushing test work, before they split off a sample for us for grinding test work in York and then Pori is also receiving a sample for some broader mineralogy testing.

This speaks to why we are able to claim to have global capabilities. No matter the testing or research need, we are able to assist our customers to get the job done. This all goes towards one goal – the customer’s benefit.

IM: How do you see these testing capabilities interacting and benefitting from other modelling work you carry out in-house? For example, do you anticipate using these facilities and the likes of the Geminex digital twin in unison to offer clients physical and digital representations of flowsheet options?

RG: Modelling is very important for us. In each project we work on, modelling and simulation are at the heart. Here in Pori, we carry out flowsheet development and technology validation. One of the outputs of our work is to end with a simulation of an industrial plant. Going from that simulation into Geminex is just one more step we will be taking in the future.

AB: At the York lab, we are now moving to a SCADA-based system to run everything: when a sample comes in, it gets tagged and identified and we then automatically know what test to run. We have tablets to, for instance, setup all the parameters of a test for an HRC 800e. We can start and stop the test on that tablet and see the real-time information coming in as the test is being carried out. That data is also being stored for future use.

We’re undergoing a program right now to build out a database function where all the post processing of this data goes on in the background and can then be seamlessly integrated into things like our HRC simulation software. We are building the backbone to carry out that real-time digital twinning.

IM: Do you anticipate your global testing capabilities to lead to a higher uptake of Planet Positive solutions?

AB: With our customers having a huge focus on sustainability, I do. As an example, since we have had the pilot-scale HRC 800e available for testing, it has been fully booked. In 2023, we are preparing for a test plan where we could take the HRC product and go directly into a pilot Vertimill. Those are two Planet Positive approaches we are putting together in a single test plant to show how far we can push energy efficiency and media consumption reduction.

RG: I would definitely agree with Alan. And to add to that – for example at Pori, we do a lot of hydrometallurgical testing and piloting, and that is only increasing with the rising demand for lithium and other battery minerals. And our customers are really looking at how our equipment is reducing their carbon footprint and other sustainability benefits.

You will hear us say it time and time again, but this is definitely a trend that we are seeing at all of our facilities.

Metso Outotec testing and research capabilities cover the entire flowsheet – from comminution through the entire operation to pyrometallurgical/hydrometallurgical processing

IM: Will these expanded testing facilities also benefit your equipment and process R&D work?

AB: I think so. We built this lab to not just be a materials testing facility, but also a research hub, especially for grinding, but also for any other Metso Outotec business area needs. There is definitely a huge opportunity out there for us!

RG: And this rings true around the globe at all our facilities. For example, in separation, we have been testing the Concorde Cell™ flotation technology in Pori for a long time. And that is how we’ve approached development of a lot of our other innovations that go to market.

IM: How would you say industry testing requirements have changed over, say, the last five years?

AB: From our perspective, I am seeing more comprehensive test programs come through.

Instead of, say, one certain test, it is an entire test program with specific timings around evaluations and the ability to develop the flowsheet through the testing required. There is more collaborative designing of the flowsheet taking place through testing than there was five or 10 years ago.

RG: It is certainly more comprehensive now than it previously was.

For example, we carry out early engagement with our customers in Pori and start developing a flowsheet and evaluating the ore types.

The amount of material that is tested nowadays is much bigger than it was before. Obviously, it is not just limited to this example, because, as Alan mentioned before, we’ve got this connection between all our facilities to ensure our customers get exactly what they need from their testing program.

Also, our customers think about different drivers in the process very carefully and want that reflected in the test work. That could be more evaluation on the water they consume. They also look at the energy expended, on top of the expected recoveries and metal grades.

There is more emphasis on sustainability, even at these early stages, in addition to looking at how the ore types may change over time and what impact this will have on the processing requirements.

This is where our extensive simulation and modelling capabilities are leveraged for the biggest impact.

IM: Anything else to add?

RG: Pori and York are but a fraction of the expertise of the wider Metso Outotec research and testing portfolio; one that continues to expand in line with customer requirements. We don’t just cover mining, either – like our equipment offering, we provide research and testing services for the whole flowsheet.

And we are continually improving our capabilities in this space for our customers. So, stay tuned for the future and where we can take research and testing!

Eriez promotes Jaisen Kohmuench to COO position

Comminution of minerals, Mineral processing, Mining equipment, Mining people, Mining services, , , , ,

The Eriez® Board of Directors has appointed Jaisen Kohmuench to the newly created position of Chief Operating Officer (COO), a role that will see Kohmuench manage all of the company’s major operations, including Eriez-USA, Eriez Global Flotation and Eriez international businesses.

Kohmuench, already within the Eriez corporate leadership team, will continue to work closely with corporate executives and functional leaders to ensure Eriez’s sustained strategic growth, the company said.

Over the past two decades, Kohmuench has made significant contributions to Eriez, steadily ascending in the organisation across multiple business areas and geographies. He served most recently as Vice President-International, a position he held for three years before accepting this latest promotion to COO.

Kohmuench earned bachelor’s, master’s and doctorate degrees in mining and minerals engineering from Virginia Polytechnic Institute and State University. He has spent the entirety of his career with Eriez, joining the company in 2000 as a Process Engineer.

Eriez President and CEO, Lukas Guenthardt, said: “From his earliest days in research and development, through his role managing the US Flotation group and later in an overseas assignment as Managing Director for Eriez-Australia, Jaisen has distinguished himself as a talented leader with tremendous financial and operational acumen. He has developed and directed immediate and long-term business plans and profitable growth initiatives across Eriez’ global magnetic, flotation and service operations sectors.”

Among his many notable career achievements, Kohmuench is credited as an inventor on more than a dozen patents and has authored numerous technical papers for prominent scientific and technical journals.

“With Jaisen’s guidance and the support of his highly skilled worldwide team, Eriez is well-poised to successfully propel our business into the future,” Guenthardt said.

Metso Outotec highlights magnetic separation expertise

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Metso Outotec has introduced a magnetic separators portfolio that, it says, caters to a wide variety of applications with the separators’ flexible modular design enabling superior separation selectivity and improved recovery of fine and ultra-fine particles.

Metso Outotec High Gradient Magnetic Separators are designed to recover weakly magnetic material from non-magnetic matter and can be used for many applications including the processing of iron ores, rare earths and other weakly magnetic minerals, which are not normally treatable by ordinary magnetic separators.

The Low Intensity Magnetic Separators, which are designed to recover magnetic material from non-magnetic matter, are part of Metso Outotec’s Planet Positive product offering. The separators use physical separation and require no chemicals in the process. The Low Intensity Magnetic Separators feature modular design with several frames and process tank designs and use a common magnetic drum for ease of selection of the best machine for each individual application, the company says.

Metso Outotec’s offering also includes the SLon® Vertically Pulsating High-Gradient Magnetic Separator, which processes fine, weakly-magnetic minerals. The units are wet, high-intensity magnetic separators that use a combination of magnetic force, pulsating fluid and gravity to process minerals.

Jan Jirestig, Product Manager, Magnetic Separators, Metso Outotec, says: “We have a long history in magnetic separation, and we delivered the first separator back in the 1890s. Since then, we’ve developed and delivered thousands of magnetic separators worldwide. We are continuously developing our products, securing our position at the forefront of the magnetic separation industry.”

Primero completes WHIMS project at Fortescue’s Christmas Creek iron ore op

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Primero Group says it has completed the construction of a Wet High Intensity Magnetic Separation (WHIMS) processing plant at Fortescue Metals Group’s Christmas Creek iron ore mine in Western Australia.

The plant is expected to improve product grade and mass recovery from the desands unit at the Christmas Creek Ore Process Facility #2.

The flowsheet is based on a simple and robust configuration, where wet screen undersize at a nominal -1 mm is treated in open circuit through a low intensity magnetic stage, followed by a vertical WHIMS stage to produce a concentrate stream and a tailings stream, which can be integrated with the existing process and auxiliary equipment. The vertical WHIMS project entails the redirection of the wet screen undersize stream from the existing scrubbing circuit to feed the brownfield magnetic separation plant.

“We can proudly say that despite the impacts of COVID-19 and the fast-tracked nature of the project, the plant was successfully delivered and commissioned in less than 12 months – meeting all safety and project key performance indicators,” the company said.

Primero put the project’s success down partly to the “enhanced opportunity for collaboration early contractor involvement (ECI) provides”.

It added: “A flexible approach to project development that ensures the needs of all project stakeholders can be met prior to detailed design and implementation in a lump sum engineering procurement and construction (EPC) environment. This constructive, relationship-based contracting continued throughout construction, commissioning and now operation – demonstrating the power of the ECI contracting model when coupled with Primero’s unique, vertically integrated EPC capability.”

Steinert to bolster sorting system test capacity in Pulheim

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Steinert is to introduce additional sorting lines for mining and waste recycling at its new test and development centre in Pulheim, Germany, the company says.

The new lines are being installed in an effort to better achieve the company’s aspiration of “test before you buy”, allowing it to “respond with ever more accuracy to the sorting aims of extraction, purity and profitability for each sorting task”, Steinert said.

Steinert’s sorting solutions are used throughout the mining industry as a way of pre-concentrating material ahead of milling.

The metal sorting line of the new test and development centre will official go into operation on September 22. This milestone will be marked with a virtual event held on that day.

By opening the new building, the company is trebling its testing capacity, allowing it to be more flexible in responding to customer demands, it said.

“The processing sequence deployed in the sorting systems is the same as that used in a real industrial plant,” Peter Funke, CEO of the Steinert Group, said. “We are delighted that even more customers can try out our technology, from magnetic separators to sensor-based sorting systems, such as X-ray transmission, X-ray fluorescence and near-infrared (NIR),”

The research and development team is also moving to the same building in Pulheim, seven kilometres away from STEINERT’s headquarters in Cologne, allowing customers to derive even more benefits from the latest developments, the company said.

Bunting ups the Electro Overband Magnet stakes for Agnico’s Kittilä gold mine

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The largest Electro Overband Magnet ever built at the Bunting manufacturing plant in Redditch, England, is destined for installation at the Agnico Eagle-owned Kittilä gold mine, in northern Finland.

Over a 12-month operating period, the Overband Magnet will lift and separate damaging tramp metal from around 2.7 Mt of conveyed ore, protecting crushers, screens and other up-stream process plant, according to Bunting.

One of the world’s leading designers and manufacturers of magnetic separators for the recycling and waste industries, Bunting has European manufacturing facilities in Redditch, just outside Birmingham, and Berkhamsted, both in the UK.

The Electro Overband Magnet uses high-strength magnetic forces to lift and then automatically discard tramp ferrous metal present in conveyed ore, Bunting says.

“In operation, the large Electro Overband Magnet is suspended in a crossbelt orientation across the non-magnetic head pulley of a conveyor transporting mined ore,” the company explains. “Any tramp ferrous metal entering the deep and strong magnetic field is attracted to the face of the electromagnet and lifted up and onto the surface of a continuously-moving self-cleaning rubber belt.

“Reinforced and heavy-duty rubber wipers on the belt catch the captured metal, transferring it to the side and away from the conveyed ore. As the wipers move the ferrous metal out of the Overband Magnet’s magnetic field, it drops under gravity into a collection area.”

This latest Electro Overband Magnet is part of a major plant expansion and upgrade at Kittilä, Bunting said. This will see ore production go from 1.6 Mt/y to 2 Mt/y, with gold output expected to rise by 50,000 oz/y to 70,000 oz/y when completed.

When initially contacted, Bunting engineers worked closely with the mine operator to design a bespoke Overband Magnet for the difficult application, it said. Design considerations included the width of the conveyor, the volume of conveyed ore, and the size and shape of the tramp ferrous metal. With these details, the Bunting design team calculated the minimum magnetic field and force density for optimum separation using an in-house developed Electro Overband Magnet Selection program.

These criteria provided the basis for the design of the electromagnetic coil by the Bunting-Redditch engineering team.

The final design is a model 205 OCW50 Crossbelt Electro Overband Magnet, with the 17 kW electromagnetic coil, generating the strong magnetic field, cooled using recirculated oil. Efficient cooling of the electromagnet is critical as the magnetic force decreases proportionally to the rising temperature of the coil, Bunting said.

The Overband Magnet is 4.2 m long, 3 m wide and 2.2 m high, and weighs just over 13 t.

The Electro Overband Magnet is designed for positioning in a crossbelt orientation over the non-magnetic head pulley of a 1,600 mm wide conveyor, inclined at 12° and travelling at 0.75 m/s. The conveyed ore has a particle size range of between 70-400 mm, Bunting said, varying in conveyed capacity between 450-765 t/h (equating to 2.7 Mt/y).

“The tramp iron ranges widely in size and nature and includes steel rebar (2,400 x 20 mm diameter), cable bolts (600 x 15 mm diameter), steel mesh, and broken drill bits,” Bunting said. “With a maximum working gap of 600 mm (distance between the magnet face and the bottom of the ore conveyor), the Electro Overband Magnet is designed to lift and separate the tramp metal through a splayed burden of up to 500 mm. This requires a substantially deep and strong magnetic field and related force density.”

Adrian Coleman, General Manager of Bunting’s Redditch facility, said large mining projects, such as this, often require bespoke solutions.

“Over 40 years, we have gained considerable experience in designing and building large Electro Overband Magnets,” he said.

“However, this was the largest we have ever manufactured at Redditch, presenting many challenges, which were overcome. And the design and manufacturing process all took place during the COVID-19 crisis.”

Bunting ups the mineral separation ante with ElectroStatic Separator

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Bunting has launched a new separation device that, it says, significantly broadens the company’s separation capabilities, opening new opportunities for optimising mineral reserves.

The development of the ElectroStatic Separator comes in response to enhanced material separation requirements in the recycling, plastics and minerals industries, Bunting said.

It uses tungsten electrode wire to generate electrostatic charges to separate dry liberated particles, exploiting the difference in electrical conductivity between various materials in a feed material to produce a separation.

“The separation depends on a number of key material characteristics including conductivity, moisture content and size range,” Bunting said. “In many applications, often due to the fine particle size, the ElectroStatic Separator is the only technology that enables a separation (eg -2 mm granulated cable scrap).”

The technology also replaces less environmentally friendly separation processes such as froth flotation in mineral processing applications (eg separation of rutile from silica sand), according to the company.

In operation, the technology uses the difference in conductivity between insulators (eg plastics) and conductors (eg copper and aluminium) to obtain a separation on an earthed roll. A vibratory feeder evenly feeds a material mix onto the top of a rotating earthed metal roll, with the rotating roll transferring the material under an electrode bar inducing an electrostatic charge. Non-conductive materials (ie insulators) adhere to the earthed roll via an image force, while the conductors lose their charge quickly and, under centrifugal force, are discharged, according to Bunting. This enables a separation.

ElectroStatic Separators provide material segregation in plants processing minerals, producing plastics, and recycling secondary metals, the company says, with differences in conductivity found in recycled materials and minerals sufficient to enable excellent levels of separation.

“Indeed, this includes the separation of metals with different conductivity,” the company said.

The mineral processing industry commonly uses ElectroStatic Separators in conjunction with high intensity magnetic separators such as Bunting’s own Rare Earth Roll Magnetic Separator and Induced Magnetic Roll Separator, it said. This combined separation process is used when processing beach sands, for example.

The new separator is available as a single or double staged system in feed widths of 500 mm, 1,000 mm and 1,500 mm to suit a specific application.

The Bunting Centre of Excellence in the UK includes a laboratory-scale model of the new ElectroStatic Separator, according to the company.

Bunting expands Permanent Overband Magnet range

Mineral processing, Mining equipment, Mining services, , , , ,

Bunting has released a new model Permanent Overband Magnet that, it says, is specifically developed for use on mobile plant such as crushers and screens used in mining, quarrying and recycling.

The PMax model is a lighter and more compact design that meets specific requirements of reduced maintenance time and lighter weights, it said. It has been released alongside the Easibelt Permanent Overband Magnet for recycling and bulk handling terminal applications. These models come on top of the classic PCB model in the Overband range.

The design of the Overband Magnet is simple with two pulleys mounted on a frame either side of a permanent magnetic block, according to Bunting. It is positioned above a conveyor, either over the head pulley, or more commonly across the belt. In operation, conveyed material passes under the Overband where the strong magnetic field attracts, lifts and then automatically discards tramp ferrous metal.

The PMax is 15% lighter than the standard PCB model across the range and 12% shorter in length, according to Bunting. These reductions result in a 14% higher magnetic force to weight ratio. It operates at a maximum working height of 300 mm (above the conveyor) on belts with widths between 600 and 1,500 mm.

The reduction in weight and size is achieved through adopting new manufacturing processes, including investing in new production plant, the company said. The new design release was in response to customer requests across Europe, it added.

Adrian Coleman, the General Manager of Bunting-Redditch, said: “Our PCB model has been an industry-standard for several decades and remains the optimum design for many applications. However, the PMax is specifically designed as a lower weight option for mobile plant, whilst the Easibelt offers significantly reduced maintenance time.”

Eriez makes a case for DVMF tech in hard-rock lithium sector

Energy minerals, Industrial minerals, Mineral processing, Mining equipment, Mining services, , , , , ,

Eriez says it’s high-intensity Dry Vibrating Magnetic Filter (DVMF) technology holds the key to removing very fine iron-bearing contaminants from hard-to-flow powders, such as lithium, to produce higher quality end-products.

In a recently published white paper, the separation technology leader says the DVMF technology has been validated as the most effective separation process for hard-rock mining lithium applications.

‘Hard Rock Mining: High-Intensity Dry Vibrating Magnetic Filter (DVMF) Removes Fine Iron-Bearing Contaminants Found in Lithium and Other Hard-To-Flow Powders’ was written by Eriez Mining and Minerals Processing Director, Jose Marin.

According to the paper, the DVMF is ideal for both lithium producers and users, with typical DVMF applications including fine sand, glassmaking, talc, clays and various other finely divided industrial minerals and chemical products.

The DVMF uses a high-intensity electromagnet and flux converging matrix, which amplifies the magnetic field and provides high-gradient collection sites for the magnetic material as the feed materials filter through, according to Eriez.

The canister is attached to dual high-frequency, low-amplitude vibratory drives and these drives deliver a strong vibratory action to the canister assembly, which enhances the fluidity of very fine powders, resulting in a smooth and even flow of product through the matrix grid.

On the DVMF’s hard-rock lithium separation credentials, Marin explained: “Eriez 5,000 gauss strength DVMFs reduce contamination to parts per billion, rather than parts per million. These results are a real breakthrough in terms of magnetic contaminant removal in hard-rock mining.”

To learn more about Eriez DVMFs and download this white paper, click here.

Vale exploring dry stacking/magnetic separation to eradicate tailings dams

Comminution of minerals, Environmental, Mine operation news, Mineral processing, Mining equipment, Steel and iron ore, Sustainable mining, Water management, , , , , , , ,

Vale has confirmed a Reuters news report from last week stating that it would spend an additional BRL11 billion ($2.5 billion) on dry iron ore processing over the next five years.

The company said it has invested nearly BRL66 billion installing and expanding the use of dry processing, using natural moisture, in iron ore production in its operations in Brazil over the last 10 years and it would carry on this trend.

“By not using water in the process, no tailings are generated and, therefore, there is no need for dams,” the company said, added that about 60% of Vale’s production today is dry, and the goal is to reach 70% in the next five years.

Dry processing is used in the mines of Carajás, Serra Leste and the S11D Eliezer Batista Complex (pictured), in Pará, Brazil, and in several plants in Minas Gerais. In Pará, in the Northern System, about 80%, of the almost 200 Mt produced in 2018 was through dry processing. The main Carajás plant, Plant 1, is in the process of conversion to natural moisture: of the 17 plant processing lines, 11 are already dry and the remaining six wet lines will be converted by 2022.

Serra Leste’s treatment plants, in Curionópolis, and S11D, in Canaã dos Carajás, also do not use water in ore treatment, according to Vale. In S11D, for example, the use dry processing, using natural humidity, reduces water consumption by 93% when compared to conventional iron ore production.

In Minas Gerais, dry processing increased from 20%, in 2016, to 32%, in 2018. Today, this type of processing is present in several units, such as Brucutu, Alegria, Fábrica Nova, Fazendão, Abóboras, Mutuca, Pica and Fábrica. “Over the following years, the objective is to roll it out at other locations in Minas Gerais, such as the Apolo and Capanema projects, which are currently under environmental licensing,” the company said.

Vale said: “Dry processing is linked to the quality of the iron ore extracted from mining. In Carajás, as the iron content is already high (above 64% Fe), the ore is only crushed and sieved, so it can be classified by size (granulometry).

“In Minas Gerais, the average content is 40% iron, contained in rocks known as itabirites. To increase the content, the ore is concentrated by means of wet processing (with water). The tailings, composed basically of silica, are deposited with water in the dams. The high-grade ore resulting from the process can then be transformed into pellets at the pelletising plants, increasing the added value of the product.”

The mills that operate dry processing in Minas Gerais depend on the availability of ore with higher levels – about 60% Fe – still found in some mines in the state. “In order to achieve the necessary quality, and be incorporated into Vale’s product portfolio, it is necessary to blend with Carajás ores, carried out at Vale’s distribution centres in China and Malaysia. The process allows Vale to offer excellent quality ore which can be tailored to meet the needs of our clients,” the company said.

The blending of the product with natural moisture does not eliminate the need for humid concentration of the low-grade itabirite used in the production of pellets. However, to reduce the use of dams, Vale plans to invest approximately BRL 1.5 billion on dry stacking technology in Minas Gerais between 2020 and 2023. This technique filters and reuses waste water and allows the latter to be stored in piles, thus reducing the use of dams. The goal is to achieve up to 70% of the waste disposed in the coming years, but success depends on the improvement of technology and external issues, such as environmental licences, Vale said.

“Today, Vale doesn’t have a dry stacking operation that can deal with the production quantity especially in a region with high rainfall indices, such as the Ferriferous four-side, in Minas Gerais. The available dry stacking technology is used on a small scale around the world – up to 10,000 t/d of tailings produced – in desert regions or with low rainfall. In Minas Gerais, Vale’s tailings production quantity is, on average, 50,000 t/d per unit,” Vale said. In 2011, the company developed a pilot project on the Cianita stack in Vargem Grande, after an investment of BRL100 million.

The studies were completed in 2018 and the technicians evaluated the geotechnical behaviour of piles under rainy conditions. The next tests will be applied on an industrial scale at the Pico mine in the municipality of Itabirito, Vale said.

“Another solution that has been studied is the dry magnetic concentration of iron ore based on the innovative technology developed by New Steel, a company acquired by Vale at the end of 2018 for BRL1.9 billion,” Vale said. “The dry magnetic concentration eliminates the use of water in the concentration process of the low-grade ore, which disposes the waste generated in sterile piles, similar to what happens in dry stacking. This technology, however, is in the industrial development stage and is not yet ready to be applied on a large scale.”