Tag Archives: leaching

Metso takes aim at refractory gold, base metal leaching ops with new OKTOP BIOX tech

Metso is extending its hydrometallurgy offering with the launch of OKTOP® BIOX® Reactor, a solution, it says, is ideal for the pre-treatment of refractory gold concentrate and base metal leaching.

OKTOP BIOX Reactor is part of the Metso Plus offering (the rebranded Planet Positive offering) and enables enhancing oxygen mass transfer to improve energy efficiency and process performance during the leaching process.

“The OKTOP BIOX Reactor provides increased operational efficiency with the most energy-efficient agitator design available for the BIOX process,” Waldemar Olivier, Senior Process Engineer, Gold, at Metso, said. “The reactor features a dual-pumping agitator that maximises surface aeration, increasing oxygen mass transfer and enhances foam entrainment back into the slurry using a novel surface aeration ring. Thanks to its innovative design, it delivers more than 20% energy savings on agitation power, lowering operational costs.”

Metso says it provides comprehensive support from design to service for OKTOP BIOX Reactor deliveries. This includes, for example, full process design, mechanical guarantees and test work capabilities. To support steady operational efficiency, Metso’s in-house engineering team offers accurate monitoring and optimisation services.

With over 1,200 installations globally, the modular OKTOP Reactor is trusted by industries worldwide and has built an excellent reputation for being safe and reliable and ensuring consistent performance with excellent product quality, according to the OEM. Metso BIOX technology boasts 14 installations that have resulted in combined gold production of more than 36 Moz to date. The OKTOP BIOX Reactor features a novel agitator specifically designed for this application.

Draslovka goes commercial with GlyCat leaching at Barrick’s Buylanhulu

Draslovka a.s., a provider of sustainability-led technologies, reagents and services for mining and the energy transition, has progressed its previously announced partnership with Barrick Gold and, today, announces the start of commercial use of its revolutionary glycine leaching technology for gold, GlyCat™, at Barrick’s Buylanhulu operation in Tanzania.

In addition, Draslovka and Barrick’s strategic partnership will now include a broader testing program in 2024 that will span multiple mining sites.

At Bulyanhulu Gold Mine, the GlyCat pilot program has led to an 80% reduction in cyanide consumption while achieving gold recoveries that are comparable with traditional cyanidation, Draslovka says. With GlyCat as part of the process, the mine’s tailings show undetectable levels of WAD and are free of cyanide, thereby reducing detoxification requirements and costs.

Pavel Bruzek Jr, CEO of Draslovka, said: “This licensing agreement follows a highly successful pilot programme that proved the major benefits GlyCat offers to the gold mining industry. GlyCat provides significant economic and sustainability benefits at a time when the future of mining is conditional on cost savings, sustainable operations and securing social license to operate. I look forward to continuing to work with Barrick and am confident others in the sector will soon see that GlyCat is revolutionary and its development will enable a major shift for the gold mining industry through massive economic and environmental benefits. Barrick was the first major mining company to recognise the potential glycine leaching offers and it is a pleasure and honour to work with the team on its commitment to sustainable operations.”

Simon Bottoms, Barrick Mineral Resource Management & Evaluations Executive, added: “The application of GlyCat technology within our operations has significant potential to deliver improved operational efficiencies and cost savings, whilst also improving our environmental legacy. Consequently, we are very pleased to embark upon this strategic partnership with Draslovka to take advantage of this innovative technology across our global operations.”

Think & Act Differently Cohort set to revolutionise in-situ recovery

The Think & Act Differently (TAD) incubator, powered by BHP, has announced its support for a new cohort that has come together to develop an innovative technology roadmap for in-situ and alternative extraction options, the company says, lower the impact of mining and processing.

In collaboration with its partner, Unearthed, the TAD Cohort was curated through a venture-style selection process, which also involved selection of members from the TAD Ecosystem.

This cohort is supported and funded by BHP, Boliden, Rio Tinto, South32 and IGO, as part of the TAD Collaboration that is commited to unlocking new technologies and reimagining lower impact mining and processing to find value in overlooked resources.

The TAD Cohort comprises a diverse group of companies ready to apply new ways of thinking to in-situ recovery. It includes:

  • Auric BioRecovery: using bio recovery processes to release metal from tailings;
  • Clean & Recover: ElectroClear recovery of water from acid mine drainage;
  • Destiny Copper: Using high activation potential and chemistry to eliminate electricity requirements for plating copper;
  • Draslovka: A ‘green’ recyclable lixiviant, selective in leaching base and precious metals from host minerals (pictured in a test lab above);
  • Eden GeoPower: Rock preconditioning technology to enable in-situ solution mining;
  • Ekion: Enabling the in-situ extraction of metals using electrokinetics;
  • EnviroGold Global: Clean-technology process for metal recovery from sulphide mine tailings and smelter residues; metal recovery includes strategic, critical, base and precious metals;
  • LeadFX: Metal recovery with CO2 capture;
  • Loop Hydrometallurgy: Clean technology unlocking copper, rare earth elements and other metals from tailings and concentrates;
  • Muon Vision: Cosmic ray sensing for tailings and heap leach monitoring; and
  • Precision Periodic: Enabling industrial scale chromatography using novel filtration media to recover and concentrate elements in mining applications and treatment of wastewater.

Arizona Sonoran Copper hires Ausenco for Cactus and Parks/Salyer project PFS

Arizona Sonoran Copper Company says it has engaged Ausenco as lead engineer to deliver an integrated prefeasibility study (PFS) at the Cactus and Parks/Salyer project, in Arizona, USA, by early 2024.

The project, on private land, is a brownfields site with in-place infrastructure and is accessible via highway.

Additionally, the company is pleased to announce the appointment of Victor Moraila as Chief Engineer, joining as the company transitions into a US-based copper developer.

Ausenco will initially review the Cactus draft PFS and incorporate into the new re-scoped PFS, which includes Parks/Salyer. The study will explore a simple heap leach operation, targeting a potential of 50,000 tons (45,359 t) per annum of LME Grade A Copper Cathode from an on-site solvent extraction/electrowinning (SX/EW) plant.

Mineralised material will be sourced from four deposits initially, including Stockpile, Cactus East, Parks/Salyer and Cactus West.

Pending a successful metallurgical program with Rio Tinto’s Nuton Technologies, and a subsequent commercial agreement, the company and Ausenco will layer in the primary sulphides as a fifth source of mineralised material for the SX-EW plant.

Back in July, Arizona Sonoran announced it had entered into a one-year exclusivity period with Nuton™, a Rio Tinto Venture that, at its core, is a portfolio of proprietary copper leach related technologies and capability. The sulphide potential is not included in the 2021 Cactus preliminary economic assessment, which contemplated a simple heap leach and SX-EW operation over an 18-year mine life, producing an average of 28,000 t/y of LME Grade A copper cathode.

In addition to its own technical staff, Ausenco will lead a technical consultant team comprised of Samuel Engineering, AGP Mining Consultants, Stantec, MineFill Services, Clear Creek Associates and Call & Nicholas Inc.

As part of the PFS work for the project, the company and Ausenco have agreed to complete trade-off and optimisation studies and detailed mine production scenario analysis, in conjunction with AGP Mining, around the following areas:

  • Mineralised material sources from an open-pit expansion (Cactus West), underground development (Cactus East and Parks/Salyer), and the existing stockpile;
  • Ore handling, storage, and agglomeration;
  • Leach pad design and operation;
  • Acid storage, consumption and handling;
  • Solvent extraction and electro-winning;
  • Existing and new infrastructure (as required);
  • Preliminary design of access roads in coordination with mine access roads;
  • Preliminary design and location of mine support facilities; and
  • Mine and geotechnical design.

A PFS detailing the oxide and enriched mineralised material is projected to take approximately 10 months to complete, with results currently expected in the December quarter of 2023. Based on the results of current metallurgical testing with Nuton, layering in the primary sulphide material into the mine plan would extend delivery into early 2024.

George Ogilvie, ASCU President and CEO, said: “As Arizona Sonoran Copper Company emerges as a mid-tier copper developer, we are thrilled to welcome the depth of experiences of both Victor and Ausenco; each rooted in quality and value-driven projects. Looking forward, Arizona Sonoran Copper Company is bolstering the technical services team, necessary team to deliver domestically produced copper into the US copper supply chain, from the third largest independent copper deposit in the US.”

Jetti Resources to deploy catalytic leaching tech at Freeport-operated El Abra

Jetti Resources has reached an agreement with Sociedad Contractual Minera El Abra and Freeport-McMoRan to deploy Jetti’s leaching technology at the El Abra copper mine in Chile, majority-owned and operated by Freeport.

The use of Jetti’s technology will enable El Abra to produce more copper while taking advantage of existing infrastructure and will generate strong financial returns, according to Jetti.

This is not the first Freeport installation for Jetti, with a spokesperson for the mining company recently confirming to IM it was trialling the technology through “a commercial installation” at its Bagdad mine in Arizona, USA.

Jetti’s catalytic technology will be deployed on the existing leach stockpiles at El Abra and will target over 20 MIb/y (9,072 t/y) of incremental copper cathode production after an initial ramp-up period. The project will leverage existing El Abra infrastructure including excess tankhouse capacity sufficient to process all production from Jetti’s leaching technology. Engineering work for the establishment of Jetti’s on-site catalyst facility is already well advanced, with construction expected to commence in the first half of 2023 and commissioning expected in the second half of the year, Jetti said.

El Abra is an open-pit copper mining complex with a large sulphide resource as well as an established leaching operation. In 2022, El Abra produced approximately 200 MIb of copper.

Mike Outwin, CEO and Co-Founder of Jetti Resources, said: “El Abra is Jetti’s first deployment in Chile, and we are delighted to extend our partnership with Freeport to a second site. Real momentum is building behind the deployment of Jetti’s technology as its unique technological, commercial and environmental benefits become increasingly clear. We look forward to working with Freeport to successfully unlock profitable new pounds of copper with a low carbon footprint and with reduced water consumption.”

Freeport furthers its leading copper leaching excellence

Among the new applications, technologies and data analytics Freeport-McMoRan is advancing as part of a plan to improve copper recovery from its leach processes in North and South America is Jetti Resources’ patented catalytic technology, the company has confirmed to IM.

In its December quarter and 2022 annual results, released late last month, the leading copper miner said it believed the leach innovation initiatives it was pursuing provided potential opportunities to produce incremental copper from its large existing leach stockpiles and lower-grade material currently classified as waste.

The company has been exploring the potential for incremental low-cost additions to its production and reserve profile for some time, saying in the latest results release that it had identified opportunities to achieve an annual run rate of 200 MIb/y (90,718 t/y) of copper through these initiatives by the end of 2023.

Freeport has a long history of copper leaching production with its Americas division, which includes assets such as Morenci and Cerro Verde, having developed and implemented industry-leading technologies for leaching of oxide ores.

The company has been pursuing internal and external initiatives to expand this leading position, focusing on traditional ores and sulphide orebodies that have been typically considered difficult to leach, like chalcopyrite.

This is where Jetti’s technology comes in.

The Colorado-based company has developed catalytic technology to allow for the efficient and effective heap and stockpile leach extraction of copper. This bolts onto existing solvent extraction/electrowinning (SX/EW) leaching plants so it can be deployed rapidly with limited capital expenditure and, because it uses no heating or grinding, has low operational costs. In addition, there are huge environmental benefits from using leaching over pyrometallurgy, according to Jetti.

A Freeport spokesperson confirmed to IM that the company was in a trial of the Jetti technology through “a commercial installation” at its Bagdad mine in Arizona, USA. This mine is one of its major leaching test hubs, with the company targeting over 3 MIb/y of incremental copper cathode production from the open-pit copper mine through this work.

Bagdad has a 77,100 t/d concentrator that produces copper and molybdenum concentrate, an SX/EW plant that can produce approximately 6 MIb/y of copper cathode from solution generated by low-grade stockpile leaching, and a pressure-leach plant to process molybdenum concentrate.

The spokesperson added: “There is potential to expand production via the treatment of additional stockpiles at Bagdad in the future based on results.”

The use of Jetti’s technology is one of several leaching initiatives the company is pursuing – some with outside vendors, some using its own technology and some with joint venture partners.

All of these are focused on not only adding low-cost production to Freeport’s large production base, but also achieving a lower carbon footprint.

Jetti, which Freeport is an investor in, has been conducting a carbon footprint study and Life Cycle Assessment (LCA) of its technology, with the LCA including analyses of typical copper mining operations without Jetti’s technology and a mining operation with Jetti’s technology installed. The LCA is being conducted in conformance with the ISO 14040/44 standard and will be critically reviewed by an independent expert.

Jetti Resources has developed catalytic technology to allow for the efficient and effective heap and stockpile leach extraction of copper

Jetti has also committed to starting to track water usage and waste at all its operations and sites, which includes the installation it has at Capstone Copper’s Pinto Valley operation, also in Arizona.

At Capstone’s operation, Jetti technology is being used extensively as part of a plan to recover up to 350 MIb of cathode copper over the next two decades from historic and new mineralised waste piles.

Teck Resources has also taken an interest in Jetti’s technology having signed an agreement for the evaluation of the solution at a number of Teck’s assets with potential copper resources outside of existing mine plans. BHP, through its BHP Ventures arm, is also an investor in Jetti.

As to Freeport’s wider leaching plans, it said it was looking to use data analytics to provide new insights to drive additional value, while new applications to retain the heat in the stockpiles were “yielding results”.

The company has assessed that it has some 38,000 MIb of contained copper in leach stockpiles deemed “unrecoverable” by traditional leach methods. Of this amount, about 50% is from the massive Morenci mine, which already has leaching production capacity of 900 MIb/y of copper.

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.

Excelsior Mining to explore Nuton leaching options at Johnson Camp mine

Excelsior Mining says it has entered into a collaboration agreement with Nuton LLC, a Rio Tinto venture, to evaluate the use of its Nuton copper heap leaching technologies at Excelsior’s Johnson Camp mine in Cochise County, Arizona, USA.

Rio Tinto has developed the Nuton technologies, an extensive portfolio of advanced copper heap leaching technologies targeted at primary sulphde minerals (including lower-grade minerals), which could not otherwise be processed using traditional leaching or sulphide processing technologies. These technologies offer the potential to produce additional copper in a cost-effective manner that has significant environmental benefits and reduces waste from new and ongoing operations.

The agreement with Excelsior adds to similar pacts Nuton has signed with Regulus Resources, McEwen Copper, Lion Copper and Gold Corp and Arizona Sonoran Copper Company.

The first stage of the collaboration involves Nuton completing certain test work on materials collected from the company’s Johnson Camp mine project to confirm that suitable conditions exist to deploy the Nuton technologies. Assuming this test work is successful, the parties would then work toward negotiating commercial terms for a full-scale deployment of the Nuton technologies at the Johnson Camp mine.

Test work is expected to commence during the March quarter of 2023 with a view toward potentially negotiating commercial terms dependent on the test results and other factors during the September quarter of 2023.

Excelsior is a mineral exploration and production company that owns and operates the Gunnison copper project in Cochise County, Arizona. The project is an in-situ recovery copper extraction project permitted to 125 million pounds (56,699 t) per year of copper cathode production. Excelsior also owns the past producing Johnson Camp Mine and a portfolio of exploration projects, including the Peabody Sill and the Strong and Harris deposits.

Rio’s Nuton venture eyes up leaching opportunities at Regulus’ AntaKori project

Regulus Resources Inc has announced a $15 million non-brokered private placement by Nuton, which will see the Rio Tinto Venture take an approximate 16.5% interest in the company and jointly undertake copper sulphide leach testing using Nuton’s copper sulphide leach technologies with samples from the AntaKori project in Peru.

The Nuton™ technologies, Rio says, have the potential to process arsenic-bearing copper sulphides with less impact on the environment and water resources than traditional concentrator processing.

Regulus has granted exclusivity to Nuton in the area of novel, patented or trade secret leaching technologies, for a period of one year after the delivery of metallurgical samples from AntaKori to Nuton for testing.

Rio, through its Nuton venture, has tabled a solution to treat primary copper sulphides such as chalcopyrite. 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.

Regulus Resources has outlined a 250 Mt at 0.48% Cu, 0.29 g/t Au and 7.5 g/t Ag indicated resource at AntaKori, in addition to a 267 Mt at 0.41% Cu, 0.26 g/t Au and 7.8 g/t Ag inferred resource.

John Black, Chief Executive Officer of Regulus, said: “The investment by Rio Tinto, one of the largest miners in the world, is another strong endorsement for the AntaKori project. Through Nuton, Rio Tinto has developed sulphide leach processing technologies that could allow for the processing of high arsenic ores without the need for additional on-site treatment or paying heavy penalties to a smelter. Utilising the Nuton sulphide leach technologies could truly be a gamechanger for the AntaKori deposit. The private placement will significantly bolster our financial position and enhance our ability to optimise the value of the existing resources in the project area.”

Rio Tinto’s Chief Executive, Copper, Bold Baatar, added: “This agreement will allow us to evaluate the potential to commercially deploy Rio Tinto’s innovative Nuton technologies for copper leaching at Regulus’ AntaKori project. Our Nuton technologies have the capacity to increase copper production for Rio Tinto and our partners, with a lower carbon footprint and leading environmental performance. Unlocking value from high-arsenic copper sulphides is a particularly exciting prospect for Nuton.”

Draslovka about to move into glycine leaching mining demonstration phase

Czech Republic-based Draslovka Holding is heading into a busy 12-month period where its glycine leaching technology will be showcased at numerous mining projects across the globe, the company told IM on the side lines of the Resourcing Tomorrow conference, in London, this week.

According to Ivor Bryan, Director of Mining Innovation at Draslovka Mining Solutions and the former MD of Mining & Process Solutions (MPS), the entity responsible for the development of the GlyCat™ and GlyLeach™ technologies, the company is 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.

MPS was acquired by Draslovka, a major sodium cyanide producer in 2022, with the aim of the transaction being to grow and develop the glycine leaching business.

Gold leach testing via GlyCat has been the major area of focus over the last decade. The process was invented to reduce cyanide consumption while maintaining gold recovery for gold ores from deposits containing nuisance copper. It has been designed to enhance the dissolution of gold and copper in gold/copper ores where glycine is used as a catalyst with cyanide in a cyanide-starved leaching environment. It doesn’t replace cyanide, but, in fact, enhances its leaching capabilities by dealing with the high-cyanide consuming copper within these gold-copper orebodies.

Yet, the company is also now starting to make inroads into the base metal space through GlyLeach, with nickel and cobalt two specific areas of interest. The technology is able to leach the targeted metals with enhanced selectivity compared with conventional methods. It will solubilise copper, nickel, cobalt and zinc, while gangue minerals such as iron, manganese, silicates and carbonates remain in the leach residue, Draslovka says.

This is allowing the company to promote that it can reduce the capital expenditure associated with processing these metals by removing the need for smelting, or in the case of tailings deposits, helping recover metal from assets previously written off as ‘waste’.

While the technology could have applications at run of mine operations, Bryan and his colleague Jackson Briggs, Corporate Development Manager of Draslovka, believe the most immediate opportunity is in tailings where the application of glycine leaching on ‘waste’ material could recover valuable metals while reducing the potential liabilities associated with such storage facilities.

Of the 10 or so projects the company has ahead of it, one is situated in Western Australia where the company is looking to recover nickel and cobalt metals from a tailings deposit of a major mining company.

Another project – much closer to fruition – is in Chile and involves leaching a carbonate-hosted copper oxide deposit containing some 600 t of material.

In both cases, the company is looking to demonstrate that it can recover valuable metals at high recovery rates, with low impact – namely rationalising reagent and water use and, in the case of nickel-cobalt, removing smelting from the equation.

This, according to Draslovka CEO, Pavel Bruzek, is a “win-win” for mining companies and their stakeholders, benefitting both the balance sheet and the operational environmental footprint.

“While we are a major sodium cyanide producer, when we saw the potential of MPS’ glycine leaching technology and the increase in metallurgical complexity of orebodies looking to be exploited, it made perfect sense to work with and promote this technology,” he told IM. “It is the responsible thing to do for the industry.”