Tag Archives: High Pressure Grinding Roll

MetsoOutotec-testing

Metso Outotec on the need for holistic testing

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!

Endeavour Mining launches construction of Lafigué gold project

Endeavour Mining has launched the construction of its 80%-owned Lafigué project on the Fetekro property in Côte d’Ivoire, following completion of a definitive feasibility study that outlined a project able to produce approximately 200,000 oz/y at an all-in sustaining cost of $871/oz over its initial 12.8-year mine life.

Based on the DFS recommendation, an upsized 4 Mt/y carbon-in-leach (CIL) plant capacity has been selected to process the ore from the Lafigué deposit, which will be a six-stage open-pit mine.

The Lafigué deposit is a near surface orebody amenable to conventional open-pit, drill and blast mining, which will be carried out by contractors, Endeavour says.

Mining will occur in 10-m benches, with double batters to achieve the final 20-m bench heights. Ore mining will occur in three to four flitches, selectively using smaller loading equipment in order to decrease dilution.

Diesel excavators and trucks will be used for loading and haulage, with a fleet comprising 400-t-class face shovels to load 180-t capacity dump trucks for waste mining, and 200-t-class excavators to load 180-t capacity dump trucks for ore mining.

Ore will be processed via the 4 M/y processing plant based on only a fresh ore feed. Over the life of mine, the plant will be fed with 94.2% fresh ore and 5.8% oxide and transitional ore with the proportion of oxide and transitional ore remaining below 30% at any time.

A two-stage crushing followed by high-pressure grinding roll (HPGR) and ball milling circuit is planned. A primary jaw crusher will crush ore to a coarse crush size, followed by secondary cone crusher to produce an intermediate crushed product where 80% passes 25 mm. This will feed to a crushed ore stockpile that feeds the HPGR circuit. Ore will then be passed through a conventional ball mill and milled to 80% passing 106 μm.

The milled ore will pass through a gravity circuit for separation and recovery of coarse free gold, to produce a gravity concentrate for cyanidation and electrowinning that can be smelted to produce gold doré. High gravity recovery of approximately 70% is estimated for fresh ore at Lafigué. The remaining milled ore will be screened and passed to a CIL circuit containing one pre-leach tank and six CIL tanks in series for leaching and adsorption. Leach residence time will be approximately 36 hours.

Following leaching and adsorption gold will be recovered from activated carbon by elution, electrowinning and gold smelting to produce gold doré.

Extensive and representative metallurgical testwork has indicated that gold is free milling with very high gravity and leach extraction potential, with a projected gold recovery rate of 95% over the life of mine.

Lafigué construction is underway with first gold production expected early in the September quarter of 2024.

Sebastien de Montessus, President and CEO, said: “We are ideally positioned to launch the construction of Lafigué, given our net cash position, the continued strong performance of our operations, and our success in de-risking the Sabadola-Massawa Expansion with a significant portion of the capital already committed on-budget. Moreover, we are seeing reduced inflationary pressures and favourable foreign exchange rates compared to earlier in the year.”

Patrick Bouisset, Executive Vice President Exploration and Growth, said: “The Lafigué discovery is a great example of how we can create significant value. For a modest exploration investment of $31 million, which represents a discovery cost of $12/oz, we have added a new cornerstone asset to our portfolio. To continue to source our projects organically, we have increased our greenfield exploration efforts, which, over recent months, have resulted in significant success at our Tanda-Iguela property in Côte d’Ivoire, where we expect to publish a maiden resource later this year.”

Kwatani wins major screening order from Central Asia copper mine

Competing with leading OEMs from around the world, vibrating screen specialist OEM Kwatani says it has snatched a mammoth export order for over 70 screens from a mining operation in Central Asia.

The order was signed in April with a large copper mine in the region, which boasts a production rate of 35 Mt/y. According to Kwatani General Manager Sales and Service, Jan Schoepflin, the machines will be rolled out and delivered over a tight schedule of just eight months.

Kwatani, now part of the Sandvik group within the Sandvik Rock Processing Solutions division, is already hard at work manufacturing the large and medium-sized screens at its South Africa-based manufacturing facility.

“This is Kwatani’s largest order to date and is probably the largest single order for screens ever placed with a company in Africa,” Schoepflin says. “We are proud to have won such a prestigious bid in the face of intense competition, showing how our global reputation has been growing.”

The order is for large double-deck multi-slope screens, which feed high pressure grinding rolls, as well as for single-deck linear screens feeding concentrators. The screens in this order will be installed on isolation frames to minimise the extent to which dynamic loads affect the plant’s building structures, the company says.

Kwatani says it is well known for its design, manufacture and servicing of large, robust screens which are engineered for tonnage.

“As the largest OEM for vibrating screens and feeders in Africa, we have had great success on the continent and abroad with our large ‘banana’ screens,” Schoepflin says. “These and our other custom-engineered screens have been supplied to over 50 countries to date.”

The stringent and lengthy technical adjudication for this project was conducted for the mine by two leading international project engineering houses. The size and value of the order ensured all the mining industry’s foremost screen suppliers participated in the bid. Other indicators of the order’s scale are that the screens will consume around 700 t of steel, and will altogether be fitted with 21,000 screening panels.

Schoepflin notes that an important consideration for customers is not only the proven quality and performance of its screens, but Kwatani’s ability to deliver on time.

“Any large capital expenditure decision on a mine is taken with time-sensitive factors in mind,” he says. “For instance, the delayed delivery of critical equipment can prevent a mine from meeting its planned production targets. This undermines the financial basis for that decision – an eventuality that no mine can afford.”

The end-customer and the project houses, therefore, had to have full confidence in Kwatani’s capacity.

With growing demand from a buoyant mining sector, the company recently added another 3,000 sq.m to its existing 17,000 sq.m facility in Spartan, Johannesburg. Its design and manufacturing capabilities are ISO 9001:2015 certified, ensuring that the latest order to Asia will comply with the highest global standards, he says.

“We also pride ourselves on the quality and resilience of our supply chain, which underpins our ability to manufacture to demanding deadlines,” Schoepflin says. “We carefully select our supply partners – most of whom are local enterprises – and collaborate closely with them to build their sustainability and responsiveness.”

To keep the project’s schedule on track, dedicated in-house project managers and procurement specialists meet regularly with supply partners to ensure a smooth and streamlined process. This has required alignment of all local and global procurement, including motors, drives and steel. The company’s agility allowed contracts and prices to be tied down for timeous delivery, despite the global supply chain disruption that lingers from the COVID-19 lockdowns, Kwatani says.

Kwatani will conduct training of the mine staff in maintenance and troubleshooting, so that they can fulfil these essential duties independently. The mine will be able to source all the necessary spares from Kwatani, who will also send an engineer or technician to site to supervise and sign off on certain major tasks.

Meeting delivery deadlines and avoiding penalties will require detailed logistical planning for the completed units, Schoepflin notes. The screens will be delivered in batches to a South African port, and shipped as break bulk due to their size. Production of the screens is expected to be complete by early 2023.

Kwatani’s mill discharge screen expertise to pay off at Namibia gold mine

Namibia’s mining scene is seeing an exciting expansion and technological innovation at a leading gold mining operation, with Kwatani supplying five mill discharge screens – all custom designed and manufactured at its Gauteng facilities.

Kim Schoepflin, CEO of Kwatani, says her company has a long history in Namibia and a strong footprint across various commodities there – including an established presence at this gold mine. It has worked with the engineering, procurement and construction contractor and the end-customer for two to three years on conceptualising the optimal solution.

“The mine is gearing up to increase its production by 50%, to take advantage of the strong gold price,” Schoepflin says. “Our role was to ensure that our discharge screens meet their exact process requirements – with our efficiencies of up to 95% – while delivering mechanical integrity for minimal maintenance downtime.”

The expansion includes the installation of two latest-technology mills – a high-pressure grinding roll (HPGR) and a vertical mill – which will boost production while reducing energy demand. Kwatani’s mill discharge screens, each measuring 3-m wide by 8-m long, will handle the coarse and fine material from the HPGR and the vertical mill. The company will also supply three silo feeders of 1.2 m by 2.5 m in size, to feed material from the silo to conveyors.

“Our screen design optimises the retention time on the deck, allowing for better screening and stratification,” Schoepflin says. “Due to the volume of slurry and water sprayed onto the screens, the added retention time assists with better drainage at lower cut points.”

The coarse screens were designed at a decline, and feature a larger screening media aperture with higher amplitude and stroke. Together with lower speed, this achieves better screening efficiency for the coarser particles. The fine horizontal screens, with smaller aperture screening media for the finer feed, were designed with a higher speed and lower amplitude and stroke; this will optimise the screening efficiency of the finer feed to these screens.

She also highlights the attention paid to the isolation of the vibrating screens. In this case, Kwatani engineers selected rubber buffers, which have higher dynamic loads but are more suited to wet applications and screens with a heavier mass.

“The number and type of buffers were defined according to the mass of the screens,” Schoepflin says. “The selection of rubber buffers for larger screens also assists with start-up and shutdown time, allowing the screens to come to rest more effectively.”

For these five screens, Kwatani, now part of Sandvik Rock Processing Solutions,  designed and supplied custom counter-balance frames to minimise the dynamic load to the plant infrastructure. The company’s screen technology includes designing its exciters in-house. This ensures that screens receive the necessary G-forces for optimal material stratification and screening, matching customers’ process requirements with the best possible efficiencies.

“To make sure our screens cope with the high capacity demands of modern processing plants, we rigorously test all units in our in-house testing facility before dispatch,” Schoepflin said. “These units began their journey to Namibia at the end of November 2021, and our team will support the commissioning when the customer requires.”

Kışladağ and Weir Minerals on the HPGR-backed gold recovery trail

The story that led to the installation of a Weir Minerals Enduron® high pressure grinding roll (HPGR) at Eldorado Gold’s Kışladağ heap leach operation in Turkey is a fascinating read, as well as a great example of the benefits of using such technology.

Back in March 2018, Eldorado announced it would suspend mining to evaluate processing options for the operation. This decision followed extensive laboratory tests that indicated gold recoveries would continue to trend downwards around the base of the open pit where mining was underway.

This suspension, plus further engineering and test work, led to the company advancing the potential development of a mill project. The transition away from its heap leaching roots to a possible mill and carbon-in-leach (CIL) process would have added significant capital costs and shortened the mine life significantly.

Before making this significant capital decision, Eldorado paused to take time to undertake the necessary technical work and sought the technical collaboration of Weir Minerals on a solution.

“It was a very challenging period,” George Burns, President & CEO of Eldorado Gold Corporation, told IM. “Kışladağ is a cornerstone asset in our portfolio. It required collaboration with our geologists, metallurgists, site teams and technology providers, including Weir, working together on a solution.”

(Credit: Eldorado Gold)

In late 2018, results showed increased recoveries from an extended leach cycle. Following a deeper understanding of the geometallurgical drivers of the sulphide component of the deposit, improved heap leach recoveries were realised by optimising the metallurgical conditions. With these improved recoveries confirmed, the heap leach plan was revised in early 2019. Eldorado announced plans to resume mining, crushing, stacking and heap leaching at Kışladağ, and suspended plans to build the processing plant.

The decision came following metallurgical test work on the material placed on the heap leach pad in 2018. Gold recovery had increasingly exceeded expectations throughout the year, providing a new, positive heap leaching outlook beyond the near term. At the same time, Eldorado worked with Weir Minerals on the potential use of an HPGR at the operation.

HPGR creates a finer particle size, which helps to liberate the gold particles, resulting in increased recoveries.

An improved understanding of the leaching process on its low-grade ore and the potential of this cost-effective grinding addition provided it with the confidence to continue heap leaching beyond the short-term time horizon previously envisaged.

“Our collaboration with Weir on this effort is an excellent example of how Eldorado collaborates with technology leaders and seeks out solutions,” Burns said. “We believe this is a strength of the company’s core business values. We are agile and flexible ‒ a good example in both business and operations to find innovative, technical solutions and demonstrate prudent capital discipline. Ultimately, the solution was the best technical and economic decision for Eldorado.”

Testing, testing, testing

“The relationship between Weir Minerals’ and Kışladağ goes back to 2013,” Bjorn Dierx, Global Product Manager Enduron HPGR, told IM.

The OEM had been provided with samples on several occasions to investigate different flowsheet possibilities.

“The benefits of HPGR in heap leaching recovery were known by the site’s crew,” he said.

Enduron technology was tested at the quaternary crushing stage before heap leaching, in the quaternary crushing stage before ball milling and at the tertiary crushing directly before heap leaching.

All the time, the mine operator, Tuprag, Eldorado Gold’s subsidiary in Turkey, was evaluating the impact on gold recovery.

Although HPGR in closed circuit with screening was also tested, most of the test campaigns were focused on a configuration with so-called ‘Partial Product Recycling’ (PPR), according to Serhat Onol, Weir Minerals Senior Process Engineer.

“This system includes splitter plates underneath the rolls which ‘cut’ a proportion of the product discharge and reverts this back to the HPGR head feed,” he explained. “This recycle stream can be adjusted online to adapt the product grind towards the downstream requirements.”

PPR is not an option for every application but for Tuprag – due to the feed and desired product size – all specifications showed it was the best route.

“The hybrid solution with screening serves to increase the flexibility and to control the circulating load to the HPGR,” Onol said.

With capacity rates of around 4,200 t/h at Kışladağ, the screening area requirement was reasonably high, he explained.

“The hybrid solution uses screening only for the recirculating stream: the centre product of the HPGR reports to downstream leaching, whereas the rest is recirculated,” he said. This not only removes the fines re-entering the HPGR and, thus, reduces the circulating load, but also avoids the over-grinding of fines before leaching.

The PPR option, itself, is a very flexible operation, with the adjustable discharge splitter plates providing the best circuit flexibility in terms of throughput and product size, according to Onol.

(Credit: Eldorado Gold)

Great expectations

With the main driver of the HPGR installation being an improved gold recovery scenario, leading to an increased heap leach life, the pressure has been on Weir Minerals to come up with the goods.

The final flowsheet, which includes a 2.4 m diameter by 2.2 m long Enduron HPGR with the capacity to process 4,200 t/h, is much simpler than the existing circuit, according to Dierx, with less equipment to maintain, control and monitor.

“A single Enduron HPGR will replace all of the five existing tertiary crushers of which liners would have an average lifetime of circa-one month with a crusher availability of 85%,” he said. “The HPGR tyres have a wear life close to 18 months, with the HPGR achieving a high asset availability of more than 95%.

“Additionally, as a result of the HPGR combined with the hybrid PPR system, the existing four tertiary screens are also being decommissioned.”

Not only has the HPGR alleviated the use of this equipment, it is also set to boost that bottom line gold recovery.

“During testing, it was determined that the circuit configuration and HPGR operating conditions, such as pressure, have a direct influence on the gold recovery,” Dierx said. “The current expectation is that the average recovery increase after the commissioning of the Enduron solution will be approximately 4%.”

This could bring gold recovery to approximately 56%, as was declared in a 2020 press release from Eldorado that highlighted a 15-year mine life at Kışladağ with an average annual production of 160,000 oz.

In action

One of the largest brownfield HPGRs Weir Minerals has ever installed has just processed its first material at Kışladağ, which is testament to the hurdles both the Weir Minerals and Tuprag teams overcame during the height of the COVID-19 pandemic.

“Despite the challenges we faced during the pandemic, we were able to fully install the machine, including pre-commissioning, in only 22 weeks,” Dierx said.

(Credit: Eldorado Gold)

This was achieved by minimising the amount of work carried out on site via pre-site testing and modular HPGR assembly.

“As the available footprint in existing sites is limited, the unique Enduron design (length:diameter ratio) not only improves the grinding efficiency but also allows for easier implementation with less civil requirements,” Dierx said.

The machine has the potential to be digitally connected to the Weir Synertrex® IoT platform where operators can benefit from direct access to maintenance specialists, who will be monitoring performance and provide necessary operating guidance.

And the Weir Minerals team is confident more Enduron HPGR installations will follow the one at Kışladağ.

“We are very proud of the product’s recognition by our customers as the Enduron HPGR has been selected for all major greenfield HPGR projects in the hard-rock space,” Dierx said. “Despite all the key Enduron differentiators, it is not only merely about the product but particularly the wider experience across Weir Minerals in both the upstream and downstream processes via our wide product portfolio.

“Particularly in these brownfield applications, the system is not operating in a vacuum and every process change influences how the overall circuit works. This requires tacit knowledge, which Weir Minerals holds across their global teams.”

Eldorado’s Burns concluded: “We are pleased to implement a solution that increases gold recovery and supports a 15-year mine life at Kışladağ, allowing Eldorado to continue to provide employment and economic opportunity in the region, as well as provide a solid foundation for future growth.

“Kışladağ has been the cornerstone asset of Eldorado for over a decade, producing over 3 Moz of gold and generating significant value for all stakeholders during that period. This project is a testament to our exceptional team and technology partners working together to execute in challenging circumstances during the pandemic.”

ABB to deliver drives and motors to Fortescue’s Iron Bridge Magnetite project

ABB has won a $26 million order from Fortescue Metals Group to deliver water-cooled variable speed drives and high voltage induction motors to FMG’s majority-owned Iron Bridge Magnetite project in Western Australia.

The project, operated under an unincorporated joint venture between Fortescue subsidiary, FMG Magnetite Pty Ltd, and Formosa Steel IB, covers the development of a new magnetite mine, including processing and transport facilities. The $2.6 billion development is expected to produce 22 Mt/y (wet) of high grade, magnetite concentrate, with first ore in 2022.

As part of the project, the Iron Bridge Joint Venture required a cost-effective energy efficient variable speed drive solution, according to ABB. These drives, to be installed in eight switch rooms, operate with a separate transformer that is located outside the room. This reduces the heat generated inside, resulting in less energy required to maintain the 25°C room temperature.

ABB’s water-cooled drives also directly support a higher voltage 33 kV network, it said. “This eliminates the need for a lower voltage intermediate switchboard and additional components, which ultimately reduces the total cost of the project,” the company explained.

Iron Bridge also selected ABB high voltage induction motors to power high pressure grinding rolls, grinding mills and baghouse fans used to separate the ore from the dust at Iron Bridge. Engineered to withstand harsh conditions, the motors offer high power efficiency, but in a frame size smaller than competitive alternatives, it said.

Mike Briggs, Business Manager for ABB Motion, Australia, said: “We have worked closely with the Iron Bridge team to ensure that we delivered an energy efficient, reliable and innovative solution. We are especially pleased to have won both the drive and the motor business, and look forward to continuing our strong relationship with Fortescue beyond the delivery of this project and supporting them throughout the mine’s lifecycle.”

Metso Outotec ticks the TCO box with latest HRC HPGR design

The design and operating principle of Metso Outotec’s HRC high pressure grinding roll has been well proven since going commercial in 2014.

The elimination of the edge effect with a flange design brings with it high throughput, while the anti-skew assembly means customers find faster machine restarts and no downtime from skewing events.

These benefits have been proven at Freeport McMoRan’s Morenci mine, in Arizona, USA, with the company’s largest unit – a HRC 3000 – having now processed more than 120 Mt of ore at that operation. This HRC 3000 is still going strong.

Yet, there was room for improvement, hence the reason Metso Outotec has just released the HRC™e HPGR.

Christoph Hoetzel, Head of Grinding business line at Metso Outotec, explained the rationale for such an update.

“To enable this flange technology, it was very important to have a simple, mechanical solution that works under any circumstances,” he told IM. “Our solution with the HRC was the arch frame, which was a mechanical fix to keep the rolls parallel at all times.

“This, however, came with a compromise. You had to have access to both sides of the machine and, in general, the units were relatively heavy and tall.”

These attributes meant that, if the customer investigated the total installed cost of the HRC – especially if they were weighing the purchase of more than one unit – the cost sometimes outweighed the benefits.

“This was a case of where the economics did not match the sustainability and efficiency of the unit,” Hoetzel said.

Metso Outotec has listened to customer feedback with the HRCe.

“The enabling factor for the flange technology is a mechanical solution for eliminating skewing on the machine,” Hoetzel said. “We have now achieved this with a much simpler, compact design. This is really where the step change has come from.”

Now, when you look at the specifications of the HRCe, which comes with a large feed size acceptance of 60-120 mm and typical capacities of 1,810-6,930 t/h, the footprint is almost the same as other HPGRs on the market, according to Hoetzel.

“Yet, the unit benefits from the proven and reliable flange design of the original HRC,” he said. “You could, potentially, even use a smaller unit for the same application.”

By reducing the size and associated installation cost that comes with the HRC technology, Metso Outotec is suddenly levelling the HPGR playing field. The advantages the company spelt out back in 2014 when the HRC technology was originally publicised now come with no cost drawbacks.

With more miners looking for not only energy-efficient grinding solutions in their flowsheets, but processing options that reduce their water intake, HPGRs are increasingly being used in tertiary or quaternary crush applications, or in lieu of traditional SAG mills.

In this regard, an updated HPGR is coming to the market at just the right time.

Metso Outotec, cognisant of this trend, has also sought to offer the benefits of its HPGR technology to the wider market.

The mechanical skew control HPGR (High Pressure Grinding Roll) retrofit kit takes the key components responsible for minimising skew from the HRC and makes the technology more accessible without the major investment or need to acquire a new machine, according to the company. The technology can also be incorporated into non-Metso Outotec machines.

These latest product updates are in keeping with Metso Outotec’s defined purpose of “enabling sustainable modern life”, fitting the mineral processing reality that miners face today.

Hoetzel reinforced this message: “Customers should not have to choose between sustainability and lowest total cost of ownership with their machines. At Metso Outotec, we truly want to be the partner for positive change, which means we really need to combine both.

“With the HRCe, we think we have achieved that.”

Metso Outotec to bring HRC benefits to other OEM’s HPGRs

Metso Outotec says it is launching the mechanical skew control HPGR (High Pressure Grinding Roll) retrofit kit for improved throughput and energy efficiency on the heels of its new HRC™e HPGR release.

The HRC HPGR was launched back in 2014 pioneering the use of flanges and non-skewing design and, now, those same benefits can be had on existing, non-Metso Outotec machines, the company says.

The new HPGR retrofit kit takes the key components responsible for minimising skew from the HRC and makes the technology more accessible without the major investment or need to acquire a new machine, according to the company.

“We are very excited to introduce the new flanged roll with mechanical skew control HPGR retrofit kit, which allows customers to maximise the performance of their existing equipment without the capital expenditure investment of purchasing expansion machines,” Jack Meegan, Product Director, SVS, Stirred Mills and HPGR at Metso Outotec, says. “This is truly a value option for an extended customer reach.”

Key benefits of Metso Outotec HPGR retrofit kit include the ability to increase throughput by up to plus-20%; improved energy efficiency with the flanges ensuring even breakage rates across the whole width of the roll; reduced circulating loads as less material bypasses the rolls and more ore continues to the next stage of the process; and reduced wear costs with the flanges allowing harder studs for longer tire life.