Tag Archives: tailings

Metso reflects on ‘benchmark’ contract win in Chile copper space

Metso has been awarded a major order worth some €55 million ($59 million) to deliver key concentrator equipment for a copper mining project in Chile.

The Metso delivery scope consists of high-capacity Nordberg® MP1250 secondary cone crushers, MF Series™ vibrating screens and energy-efficient Vertimill® VTM1500 regrinding mills.

For the flotation and separation circuit, Metso will supply multiple TankCell® and ColumnCell™ flotation cells featuring several of the largest available 630 cu.m TankCell units, as well as HCT™ High Compression tailing thickeners. In addition, Metso’s scope includes four MHC hydrocyclone clusters, of which two will be among the largest in the world.

Most of the products in the delivery scope are part of Metso’s Planet Positive offering.

Fernando Samanez, Vice President, Minerals Sales for South America at Metso, said: “Working together with the customer and the engineering company on an open collaborative model has been an extraordinary experience. The model enhanced the efficiency of the engineering process and contributed to the alignment of all parties on the targets set by the end customer. This will be a benchmark to be followed in similar projects all over the world.”

Clean TeQ and Future Element to pool tailings management resources in new JV

Clean TeQ has formed a 50/50 joint venture, the Future Element Joint Venture, with mine tailings management company Future Element Pty Ltd (FE), to, it says, focus on tailings management, metal recovery and waste remediation opportunities.

Clean TeQ will provide the JV with licences for its proprietary ATA® accelerated dewatering technology and its suite of Clean-IX® ion exchange technologies, with immediate access to both Clean TeQ’s and FE’s opportunity pipeline.

Clean TeQ’s CEO, Peter Voigt, said: “This is an exciting time for Clean TeQ as we look to leverage our technologies into market segments that are long-term value accretive for our shareholders. The JV with Future Element combines years of technical innovation and development with highly credentialled and commercially orientated executives to deliver solutions to the mining industry for its most critical problems. We aim to transform the industry and lead with environmentally sound tailings rehabilitation while generating material cashflows from what were previously considered waste management liabilities.”

The global inventory of mine tailings is estimated at 282 billion tonnes, with 16 billion tonnes of new mine tailings being produced every year, representing a significant opportunity to use Clean TeQ technologies to convert liabilities into valuable assets, Clean TeQ says. The mining industry’s social licence to operate depends on environmentally sound tailings rehabilitation. Clean TeQ’s strategy is to raise environmental standards and reduce tailings management costs via sustainable metal production and enhanced water management.

With the licensing of Clean TeQ’s proprietary ATA and Clean-IX technologies to the Future Element JV, Clean TeQ says it has established a business that can offer the mining industry a holistic, end-to-end mine tailings rehabilitation solution that:

  • Transforms tailings into benign and/or valuable products via separation of solids and water to allow solid materials to be rehabilitated or repurposed and water to be recycled or released;
  • Unlocks tailings value, via recovery and monetisation of metals and minerals, providing new profit streams and the ability to offset rehabilitation costs and liabilities; and
  • Eencompasses development, funding and operation using best-in-class tailings management by an experienced team with a track record in asset delivery.

Vale hits ICMM’s GISTM target for tailings storage facilities

Vale says it has implemented the Global Industry Standard for Tailings Management (GISTM) in 48 of its 50 tailings storage facilities (TSFs), with plans to bring the two remaining TSFs into conformance by August 2025.

The GISTM was developed after the tragic failure of a tailings facility at Brumadinho, Brazil, in 2019, through an independent process convened by ICMM, the United Nations Environment Programme and Principles for Responsible Investment.

The standard sets a high bar and contains 77 requirements integrating social, environmental, local economic and technical considerations which strive to achieve the goal of zero harm to people and the environment, according to ICMM.

Vale says of the 48 TSFs now in conformance with the GISTM, 35 are in the Iron Solutions business unit in Brazil and 13 in the Energy Transition Metals business unit (11 in Canada and 2 in Brazil).

“The two remaining Iron Solutions TSFs in Brazil have a lower consequence classification and will be in conformance with the standard by August 2025, following the criteria of the Conformance Protocols defined by ICMM,” Vale said.

The 48 TSFs in conformance meet the GISTM requirements, and some of them have action plans in place according to the Conformance Protocols, according to the company. In addition to meeting the 77 standard requirements, a TSF in conformance with the GISTM means that the oversight, monitoring and transparency of information have been and will continue to be improved, according to Vale. The focus is on the safety of people and the environment throughout the entire TSFs life cycle.

When the GISTM was published in August 2020, ICMM members committed to conform with the standard for tailings facilities classified as ‘extreme’ or ‘very high’ consequences by August 2023, and all other facilities by August 2025. Members are due to publish their progress towards conformance with the GISTM by August 5, 2023, for tailings facilities with the highest potential consequences in the event of a failure.

The ICMM said earlier this week that it anticipated some companies will not achieve full conformance with the standard’s requirements.

Implementing GISTM for Vale’s TSFs represents only one part of the company’s efforts to become safer and more sustainable, the miner says. Vale has been improving the management of its mining dams by conducting an in-depth technical analysis of the historical, current condition and performance of each structure. The preventive, corrective and monitoring actions have also been intensified, being increasingly integrated with social movements and updated according to legislation.

Vale also continues to progress de-characterisating its upstream tailings dam structures in Brazil. As of 2019, out of the 30 dams of this kind included in the program, 12 have already been de-characterised, representing 40% of the total. The program is expected to be completed in 2035. The de-characterisation of upstream facilities in Brazil is Vale’s commitment, in addition to being part of the current Brazilian federal and state legislation on dam safety.

Antamina, Barrick, BHP, Freeport, Gold Fields, Newmont, Teck and Vale form GeoStable Tailings Consortium

Gold Fields Limited has announced a new consortium of eight global mining companies has launched a multi-year initiative to develop and implement new technological applications for managing tailings.

The GeoStable Tailings Consortium (GSTC) comprises Antamina, Barrick, BHP, Freeport-McMoRan, Gold Fields, Newmont, Teck and Vale, with external expert support provided by Dr G Ward Wilson of the University of Alberta.

The GSTC will study options to combine various blends of tailings with waste rock to create ‘geo-stable’ landforms that are stronger and more stable than conventional tailings deposition methods and are likely to reduce process water consumption. It will undertake a range of research and development activities, including laboratory testing, field trials and data analysis, and will collaborate to promote best practices in tailings and waste management and foster a culture of continuous improvement across the mining industry.

Martin Preece, Interim CEO of Gold Fields, said: “The management of our TSFs has as its ultimate goal zero harm to people and the environment through their full life cycle. This is in line with the Global Industry Standard on Tailings Management, the new tailings storage facility (TSF) benchmark to which all members of the ICMM are committed to conform to. Having stable TSFs is a critical element of this standard.

“There is significant mining industry interest in developing geo-stable TSFs, but there is still a lack of a sound research and development including testing protocols to assess, compare and validate the performance of different technical approaches across different mineralogical and operational situations. Gold Fields is therefore a willing participant in this consortium and playing our role in becoming part of the solution.”

The new GSTC initiative builds on the work of a group formed to advance geo-waste and eco-tailings research previously pursued by Goldcorp, which was acquired by Newmont in early 2019.

Draslovka to bring glycine leaching expertise to OZ Minerals TAD incubator

Draslovka Holding a.s., a Czech family-owned global leader in cyanide-based specialty chemicals, says its glycine leaching technology has been selected to be part of the OZ Minerals’ Think & Act Differently (TAD) incubator and Waste-to-Value Challenge.

The latter challenge, announced back in December, sees Rio Tinto and Boliden working in collaboration with OZ Minerals to eliminate, minimise, reuse or find new value in mine tailings and ultimately reduce the global carbon footprint of the mining industry. Draslovka said: “The Waste-to-Value Challenge aims to unlock innovative technologies for managing tailings, helping the mining industry to reduce risk while extracting more of the materials the world needs from what was previously regarded as waste for the energy transition at large. Benefits that the initiative hopes to deliver include lower emissions and reduced waste.”

Draslovka offers a range of sustainable solutions to the global mining industry, and its glycine leaching technology (branded as its GlyLeach™ and GlyCat™ processes) represents the best environmentally-friendly alternative to traditional acid and cyanide leaching, according to the company. Due to its selectivity over gangue minerals and the recyclability of glycine, its use enables the recovery of both base and precious metals from lower-grade resources like tailings. This leads to a more sustainable production process and improved economics that are desperately needed to close the looming critical metal supply deficit.

Ivor Bryan, Draslovka’s Mining Innovation Director, said: “I am proud that Draslovka has been invited to participate in the Waste-to-Value Challenge with forward looking companies that understand the need to reimagine solutions for the mining industry. This aligns with our ambition to become the leading supplier for innovative and sustainable solutions for the wider mining industry.”

Speaking to IM on the sidelines of the recent Resourcing Tomorrow conference, in London, Bryan said the company was embarking on around 10 projects in the mining space, which will prove up the 3,500 hours of testing that has been conducted at MPS’ facilities in Perth, Western Australia.

Anglo American ushering in a new era of tailings disposal with Hydraulic Dewatered Stacking tech

While the El Soldado copper operation in Chile may be one of Anglo American’s smaller assets, it has a big part to play as one of the company’s FutureSmart Mining™ hubs, piloting some of its innovative mining and processing technologies, according to Phil Newman, Anglo American’s Head of Innovation.

Including in this innovative technology bracket is Anglo American’s patented Hydraulic Dewatered Stacking (HDS) technology.

Newman explained: “Mineral processing operations commonly use large amounts of water for the recovery of valuable minerals. This ultimately results in the production of large volumes of wet tailings which are disposed in conventional tailings storage facilities. If not safely constructed and maintained, they pose a major risk to communities and the environment. Eliminating these facilities is a key objective for a safe and sustainable mining industry.”

With 75% of Anglo American’s assets globally located in water-constrained areas, the company must reduce its dependence on water and it is working on technologies to help it achieve closed loop operations with respect to water, according to Newman. HDS is a key enabler of its FutureSmart Mining innovation-led approach to mining and a major step towards moving the company closer to water-less mining and reducing its footprint.

HDS demonstrates a new way to safely dispose of mining by-products and accelerates Anglo American’s progress towards the end of wet tailings storage. Ultimately, it allows the company to reclaim and reuse water, its most precious and undervalued resource, and create stable, dry, economically viable land long after mining ends.

The adoption of coarse particle recovery (CPR), another valuable FutureSmart Mining technology, was instrumental in the development of HDS, according to Newman. “It allows larger-size particles of material to be processed, reducing the need for grinding to a smaller size, thereby lowering energy consumption,” he said. “It also makes it easier for us to capture and drain water during the processing phase and recycle it.”

HDS targets the geotechnical and water recovery performance of filtered tailings but without the carbon footprint, Newman claims. Laboratory and proof of concept testing has proved the robustness of fines-free sand as a filtering medium – promising a safe, dewatered facility with the possibility of re-purposing otherwise sterilised land within months of closure. Through effective and permanent desaturation of the tailings, the geotechnical safety of the facility can be enhanced and deliver stability in excess of new Global Industry Standard on Tailings Management (GISTM) standards.

Anglo American has embarked on an ambitious demonstration of this technology, having built a bespoke 250,000 cu.m capacity HDS tailings facility at its El Soldado copper mine in Chile. The sand transportation and placement system was commissioned in August and tailings placement commenced at the start of November.

Data is being collected in real time on water balance, moisture content and consolidation, according to Newman, who said, by the end of the year, the company will be able to understand the degree to which tailings consolidation and dewatering is accelerated through the adoption of HDS.

“Our early results are already promising,” he said. “We have already measured water recovery at more than 80% (our initial target), and dewatering is continuing with up to 85% water recovery a possibility.”

Commencing the second layer of the sand drainage channel at the El Soldado trial, both Cell A and B have tailings with Cell A consolidated in less than two weeks

The trial will continue over the coming months with the second layer of the main sand berm being installed this month, followed by further tailings deposition.

Beyond the financial and environmental benefits, there is significant potential for the mining industry to leverage HDS to shift public perception on mining waste, according to Newman.

“Anglo American is keen to partner with other mining companies to accelerate the development and learning of this new technology and is open to synergistic licensing opportunities,” he added.

“We believe HDS could demonstrate that tailings can move from a risk which needs to be managed, to a safe, water-generating asset that, on completion, can deliver value-generating land to the perpetual benefit of our communities. By ushering in a new era of tailings disposal we are demonstrating how we are re-imagining mining to improve people’s lives.”

OZ Minerals, Boliden and Rio Tinto to collaborate on tailings initiative

OZ Minerals, Boliden and Rio Tinto have agreed to collaborate to unlock new and innovative technologies for managing tailings, helping the mining industry to further reduce risk while extracting the materials the world needs for the energy transition from what was previously regarded as ‘waste’, they say.

Under the umbrella of the Think & Act Differently (TAD) incubator initiative, the three companies will fund and support innovators who are working to reimagine mining and processing to eliminate, minimise, reuse or find value in mine tailings. The three companies will also collaborate on other selected innovations to pursue improved productivity while delivering benefits such as lower emissions and reduced waste.

The collaboration will support innovators by providing materials, funding, technical guidance and the potential for field trials at mine operations, the companies said. Innovators will retain ownership of their intellectual property rights, with a licence to use those rights granted to the companies that support them.

Michelle Ash, OZ Minerals’ Technology Executive, said: “We can accelerate technology much faster by working together and this is an example of how the industry can collaborate to support technology development. We hope this way of working and supporting innovators provides a model that can be replicated because accelerated technology development is likely to have a positive impact on our industry and society.”

Joanna Lindahl, Boliden Mines’ Sustainability Director, added: “By collaboration on generic challenges for the mining industry in a pre-competitive setting we will be able to make progress faster and more resource efficient. For the inventors and startup companies in the TAD incubator, it is also an excellent opportunity to get insights and business understanding from several different mining companies. We are very much looking forward for this collaboration and hope to find new opportunities to strengthen the industry in the future.”

Mark Davies, Chief Technical Officer for Rio Tinto, said: “It isn’t very often that competitors come together to collaborate on industry-critical work. One such area historically has been health, safety and environment, where we learned that sharing leading practices boosts our collective performance. We think collaborating on tailings management capability improvement could have a similar, industry-wide impact. We’re excited to be partnering with Boliden and OZ Minerals through the TAD program.”

The Think & Act Differently program, powered by OZ Minerals, works towards building an ecosystem of partners who will explore and accelerate themes that prioritise social and environmental responsibility for the development of the modern mine, the company says.

Photo courtesy of Exact Consulting

Rio Tinto’s Nuton ready to leverage its leaching R&D legacy

More than a few companies and technology providers claim to have solved the primary copper sulphide leaching conundrum, but only one has close to 30 years of R&D and the Rio Tinto name behind it.

Rio, through its Nuton venture, is the latest to table a solution to treat primary copper sulphides such as chalcopyrite, having introduced the company to the sector earlier this year in an attempt at growing the miner’s copper business.

At its centre is a portfolio of proprietary copper leach related technologies and capability that, Nuton says, offer the potential to economically unlock known low-grade copper sulphide resources, copper bearing waste and tailings, and achieve higher copper recoveries on oxide and transitional material. This allows for a significantly increased copper production outcome, according to the company.

One of the key differentiators of Nuton is the potential to deliver leading environmental performance, including more efficient water usage, lower carbon emissions and the ability to reclaim mine sites by reprocessing mine waste, it claims.

Column test work at Rio Tinto’s R&D centre in Bundoora, Melbourne

Adam Burley, Rio Tinto’s Nuton venture lead, said at the core of Nuton is an elevated temperature bioleaching process that can, in the right thermochemical conditions, deliver “peak” copper recovery from primary sulphides such as chalcopyrite.

“Taking advantage of naturally-occurring processes, we have nurtured a culture of microorganisms that establish and thrive in those optimised conditions,” he told IM. “The elevated temperatures are generated by the work of the bacteria; under the base case, we don’t need to heat the heap from external sources, which can often be financially and environmentally costly.”

This leaching core is enhanced by a range of “additives” and expertise that can, for example, deal with high precipitation and cold weather climates.

Having assembled and extensively tested this portfolio, Nuton and Burley are confident enough to state expectations of delivering greater than 80% copper recoveries from chalcopyrite ore with its process.

“This is, from our understanding, some way above the next best leaching technologies available,” Burley said.

The testing behind such numbers is extensive, dating back to 1994 when the company carried out its pilot heap leach operation and developed its initial predictive modelling capabilities at the Kennecott copper mine in Utah, USA.

“Since that time, we’ve conducted hundreds of column tests across tens of orebodies,” Burley said. “We have run columns at a range of scales – a metre high to 10 metres high – and a range of diameters – from tens of centimetres to 5-metre diameter cribs. Some of those range from tens of kilograms to 300 tonnes – large scale with a lot of instrumentation.”

Combining this body of work with a 70,000 t leaching trial the company carried out at Kennecott from 2012 to 2014, Nuton has been able to calibrate its computational fluid dynamic models to accurately predict a range of inputs and outputs for leaching suitability.

“We are left in a position today where we have a high degree of confidence in being able to evaluate the suitability of different ore types and Nuton’s leach response fairly quickly,” Burley said.

This has led to the company going out to market, partnering with companies that own deposits that pass the Nuton thresholds.

The company has signed deals with Lion Copper and Gold Corp, and Arizona Sonoran Copper Company to test out the technology on Lion’s copper assets in Mason Valley, Nevada, and Arizona Sonoran’s Cactus Mine and Parks/Salyer projects, in Arizona.

It has also more recently agreed a pact with McEwen Copper on the Los Azules project in Argentina.

These assets, agreements and potential leaching applications are all different – covering former operating mines and greenfield assets; earn-ins, exclusivity periods and equity stakes; and oxides and sulphides.

“We recognise that due to the high variability of copper deposits and mine waste that one size doesn’t fit all,” Burley said. “A single technology solution is unlikely to perform well at every site.

“Our approach is to work with our partners to understand site-specific characteristics, such as the mineralogy of the available ore and waste, designing a tailored approach by selecting the most applicable technology configuration from within the Nuton portfolio.”

And, according to Burley, these current and future agreements could see Nuton operate the equipment and plant associated with the Nuton process.

“In many cases, we envisage supporting our partners with an end-to-end process, including engineering, build out and operating the gear,” he said.

The test site at Kennecott being prepared and lined ready for the rock to be leached

While the sulphide copper recovery numbers are likely to take the headlines, Burley was able to point out several key differentiators from other leaching solutions targeting minerals such as chalcopyrite.

“Those recovery numbers are a step change, as opposed to an incremental improvement,” he said. “That gives us a lot more optionality in terms of the cutoff grade of the material we can process economically.”

And, with that higher resource utilisation, comes less waste and an overall higher process efficiency, meaning, under certain conditions, Nuton can compete with a pre-existing processing route such as a concentrator, Burley says.

“In some cases, in a greenfield setting, we could see a better economic and environmental outcome than a concentrator, particularly given no tailings or smelting is required, and you could have a finished product produced in country.”

He continued: “Our focus on ESG and our ability to process waste due to that low cutoff grade is one of the key differentiators that opens a whole set of use cases in the legacy mine domain too. Being able to restore and reclaim mine sites by reprocessing waste is very attractive.”

The eventual aim, according to Burley, is to deliver carbon-neutral copper from the Nuton process, yet Rio estimates it can already deliver 0.4 tonnes of CO2 equivalent for Scope 1 and 2 emissions per tonne of Nuton copper produced, compared with a global average of 5.2 tonnes of CO2 equivalent as per standard, conventional primary copper production.

Away from the technical elements, the “partnership” business model Nuton uses also stands out.

Nuton testing up and running at Kennecott (from previously mentioned trials)

“The approach is to work with our partners and assess the value case at specific sites, agreeing a commercial framework that works for everyone,” Burley said. “We are quite open minded as to what that might look like – it could be ownership and equity participation to royalty and licensing type arrangements.

“So, there is the financial strength Rio brings, as well as the deep technical expertise.”

These elements are clearly beneficial to any of Rio’s fellow mining companies that have projects with copper sulphides or those that will be transitioning to sulphide processing in the future, yet a lot of the progress made with these technologies was tied to the development of Rio’s own project, La Granja.

“In that case, part of the resource contains high arsenic and arsenic-related mineralogy,” Burley said of La Granja. “That was the trigger really for a concerted effort to look at an alternative to a concentrate and processing route. We made quite a number of Nuton breakthroughs in our study of that deposit.”

La Granja has been in Rio’s portfolio since winning the right to develop it in 2005, but is not currently in the development pipeline.

Asked if other assets within the company’s portfolio are potential Nuton candidates, Burley answered: “The potential exists to deploy Nuton within the Rio Tinto copper portfolio. We are currently evaluating a number of internal deployment options across our assets and joint ventures, but we also recognise the full value potential of Nuton – environmental and social, as well as financial – lies outside of the Rio Tinto portfolio.

“To capture the full size of prize that Nuton offers, we need to go out to market, which is what we have been doing pretty aggressively throughout the year and will continue to do going forward.”

The ICMM addresses mine tailings reduction ambition with new roadmap and initiative

Today, the International Council on Minerals and Metals (ICMM) has published a Tailings Reduction Roadmap which, it says, lays out innovative approaches and solutions capable of significantly reducing tailings from the mine life cycle, as part of a broader Tailings Innovation Initiative.

The initiative brings together a third of the global mining and metals industry to collaborate with technology innovators, including suppliers and academia, to accelerate technology for reducing tailings waste and to explore the potential to eliminate it in the long term, the ICMM says.

The Tailings Reduction Roadmap sets out short- and long-term technology options. These include mature solutions that can be implemented in the short term, such as coarse particle flotation technology to enhance the recovery of coarser particles of ore that have traditionally been seen as waste, and solutions with the potential to reduce tailings in more significant quantities, but that will require further development over the next 10-15 years, such as higher precision mining and artificial intelligence.

Developed through a series of engagements between technology suppliers, innovators and ICMM members, the roadmap offers strategic direction to the mining industry on how to accelerate the development and adoption of technologies to reduce tailings, the ICMM says. It addresses technological challenges, such as testing new technology on a different range of ore characteristics, as well as enabling factors, including business case and regulatory requirements, in parallel.

ICMM members are already piloting technologies laid out in the roadmap that match their commodities and site characteristics, so that learnings can be applied to solutions that can be scaled up to benefit the whole industry.

Rohitesh Dhawan, CEO of ICMM, said: “Catastrophic tailings failures in recent years including at South Africa’s Jagersfontein mine just last week have brought into sharp focus the need for urgent action to produce less tailings as we supply the metals and minerals that are critical for the energy transition and sustainable development. If we continue to use traditional production processes, we run the risk of multiplying tailings waste many times over. There is no easy solution, and we will continue to need tailings storage facilities into the future. However, this initiative signals our clear intent to act with urgency and purpose to find ways of minimising or potentially eliminating waste at every stage of the mining cycle.

“Work has already begun, but if we are to match our ambition, we need to work collaboratively in accelerating the types of breakthroughs that can be adopted widely in any existing or future operations around the world. Our ambition is that ICMM’s Tailings Reduction Roadmap and wider Tailings Innovation Initiative will help to identify and accelerate opportunities for wider collaboration and serve as a catalyst for advancing more partnerships between industry and technology innovators on piloting these technologies.”

ATG and Metso Outotec’s tailings-to-fertiliser tech progresses in BHP Tailings Challenge

Auxilium Technology Group (ATG), a start-up connected to the University of Arizona, in collaboration with Metso Outotec, has been announced as one of two finalists in the BHP Tailings Challenge, an international competition to promote the development of new technologies to reuse mine tailings.

Last year, ATG was one of 10 companies and academic research groups chosen to move on to the laboratory stage of the BHP Tailings Challenge, from an initial field of 154 applicants from 19 countries. Metso Outotec and ATG signed an agreement to collaborate on this initiative and, in April 2022, BHP chose two finalists, ATG and Americas Tailings Inc, a company that has developed a process to turn mine tailings into fertiliser products.

For the next phase, ATG plans to build a pilot tailings processing plant at the San Xavier Underground Mining Laboratory, owned by University of Arizona. Metso Outotec will contribute with advice on engineering and scale up using Metso Outotec products.

Metso Outotec supported the ATG process design concept by estimating engineering costs and providing Metso Outotec Plant Solutions technology competence. The concept considers pre-designed plant units known as “Process Islands” for almost all the process areas of the future plant, the company said.

Metso Outotec’s approach supported the project from optimal equipment sizing to optimising engineering costs and modularising the plant to meet future capacity requirements.

Mining companies like BHP are eager to find alternatives for the use of tailings, which are costly to store and regulated under environmental laws because they contain pollutants.

After initial cleaning of the tailings, the proposed process includes use of the material as construction aggregate or an insulating “geofoam” that can be sprayed or 3D printed to produce insulating blocks.