Tag Archives: metallurgy

Metso Outotec improves process audits and production transparency with new sampler

Metso Outotec says it is launching a versatile Linear Metallurgical Sampler (LMS) to enable the measurement of material balances as well as reporting to investors and other stakeholders in compliance with AMIRA P754 and other sampling standards.

The solution facilitates integration with Metso Outotec Courier® online analysers to further improve process control, it added.

Integration of online analysers will enable different types of sampling data to be combined for production analysis purposes, according to the company. By combining process history data with different process scenarios, the process control philosophy can be quickly adapted according to the ore type being processed, for instance. This enables improvement of production predictability and control of metallurgical mass balance, Metso Outotec says.

A single LMS unit can collect multiple metallurgical samples to suit different production reporting and management purposes, with each sample having its own timing and the system able to manage multiple buckets. A simultaneous flexible spot sample can also be taken without any system changes, according to the company.

On top of this, LMS offers improved production predictability and control of metallurgical mass balance, and reduced need for manual laboratory assays.

Tapio Korpela, Product Manager, Samplers, Separation at Metso Outotec, said: “The Linear Metallurgical Sampler incorporates versatile functions to monitor both sampling integrity and sample quality. Its self-diagnostic and self-cleaning system ensures representative metallurgical samples for improved process audits and production transparency. Maintenance personnel can use self-diagnostics and reporting data to enhance predictive maintenance and spares management strategies.”

Metso Outotec books zinc plant order as it agrees sale of aluminium business

Metso Outotec has signed a contract to deliver a complete package of key process equipment for a greenfield zinc plant in the Chelyabinsk region in Russia.

The contract value of approximately €100 million ($122 million) has been booked in Metso Outotec’s Decemeber quarter order intake, a quarter of which will be booked in Minerals segment and the rest in Metals segment.

The order for the Verkhny Ufaley plant includes an equipment package for zinc concentrate processing, iron precipitation, solution purification and electrowinning (EW) technologies for safe and sustainable zinc processing based on OKTOP® reactor and plant products.

The order also contains a circuit heat recovery system, zinc EW and ingot casting equipment, as well as high-efficiency cooling towers for zinc EW and gypsum removal with drastically reduced emissions compared with conventionally-designed cooling towers, the company said. Clarifying solutions for consistent solid-liquid separation, high-performance Larox® FP and RB filters with low energy consumption, as well as fully integrated digital process automation for more reliable and flexible operation are also part of the order.

“Metso Outotec has been supplying minerals processing and metals refining technologies to our customers in Russia for a long time,” Jari Ålgars, President, Metals business area at Metso Outotec, said. “The new zinc plant will utilise Metso Outotec’s proprietary technology, which is both sustainable and highly cost effective.”

Stephan Kirsch, President of the Minerals business area at Metso Outotec, added: “Metso Outotec provides leading-edge technology for extensive zinc processing plants. This includes proprietary process equipment and know-how from raw material to final zinc product and various by-products.”

The technology to be delivered is the most cost-efficient technology available for zinc raw material processing, enabling efficient zinc and by-product recovery from a wide range of primary zinc raw material, according to Metso Outotec.

In a separate press release, Metso Outotec announced it had agreed to sell its Aluminium business to REEL International, headquartered in France. The business was put up for sale a year ago and has since been reported under the company’s discontinued operations.

The business to be divested comprises of green anode plants, anode rodshops, and casthouses used in aluminium smelters as well as related equipment and services. Approximately 120 Metso Outotec employees will join REEL upon closing, which is expected to take place during the March quarter of 2021, Metso Outotec said.

The parties have agreed not to disclose the value of the transaction.

DST to help Newmont go cyanide-free with CLEVR agreement

Dundee Sustainable Technologies has entered into a Technology Transfer Licensing Agreement with Newmont for the use of DST’s cyanide-free gold extraction technology, known as the CLEVR Process™.

DST has been in ongoing discussions and technology review with Newmont regarding its CLEVR gold extraction process to evaluate and quantify its applicability on projects selected by Newmont.

Following a successful test work program in the March quarter of this year, Newmont expressed its interest in the execution of such an agreement allowing Newmont to conduct laboratory CLEVR leaching tests in its technical facilities in Englewood, Colorado.

The method used by DST uses no cyanide, produces no toxic liquid or gaseous effluent, and the solid residues are inert, stable and non-acid generating, according to the company.

David Lemieux, President and CEO, said: “We are very pleased to announce this agreement with Newmont which is the culmination of much work and dialogue between our companies. Our collaboration with a global gold producer is the result of years of continuous efforts in developing an innovative and technically sound process for the industry.”

He added: “Today’s announcement is further validation of DST’s CLEVR Process as one of the leading cyanide-free alternatives for the gold industry, and it represents an important milestone in the early-stage adoption and understanding of our technology by a world leading gold company.”

As part of the agreement, DST and Newmont, agreed to:

  • A two-year, non-exclusive licence for the utilisation of CLEVR at the laboratory scale in its Colorado technical facilities with an option to renew, for an additional two-year period under the same terms;
  • Technology implementation support by DST, including all technology laboratory protocols in addition to technical training sessions to initiate and support the technology transfer and practical operations;
  • Ongoing technology support and for DST to review the laboratory test plans, execution, and results conducted by Newmont; and
  • Any process scaling-up requirements, resulting from positive applications of CLEVR, will be conducted jointly with Newmont at DST’s technical facilities in Canada and/or on-site using DST’s technology and engineering group expertise.

The objective of the agreement is to facilitate the adoption, understanding and application of CLEVR on various gold projects being, or to be, developed by Newmont. The agreement was executed on November 25, 2020.

Dundee’s GlassLock Process engineers an opening at West Africa gold mine

Dundee Sustainable Technologies (DST) and its proprietary GlassLock Process™ is to help a West Africa mine stabilise legacy arsenic-bearing material at its gold operation following a new mandate agreement.

The mandate agreement, entered on June 8, consists of delivering an engineering package for a plant using DST’s GlassLock Process. It follows a preliminary metallurgical test program with the same customer from back in the March quarter.

This program saw over 40 kg of arsenic- and gold-bearing material received at DST’s technical facilities in Canada, whereby DST successfully combined gold recovery with the stabilisation of arsenic using GlassLock, it said.

A glass product containing over 15% arsenic was generated and successfully met the requirements of the United States Environmental Protection Agency’s toxicity characterisation leaching procedure (TCLP, Method 1311), DST said.

“As a result, the customer awarded the engineering mandate to DST to perform process optimisation and an engineering study at the prefeasibility (+/-25%) level,” it said. “The agreement includes engineering fees in the amount of C$101,000 ($74,436) to be paid to DST for this work as per its business plan to generate revenues for the corporation while the technology is progressing toward implementation.”

The final report is due at the beginning of September 2020, DST said.

Back in May, DST announced it had entered into a commercial agreement to provide engineering services to a gold and copper producer for a full-scale plant of its GlassLock Process as part of a C$600,000 Class 4 engineering package.

Since the construction of its pilot plant in 2016, DST has continued to demonstrate the validity of its technology, moving from pilot level to the industrial demonstration scale, where arsenical material was processed to generate vitrified arsenical glass, containing up to 20% arsenic while meeting the TCLP Method 1311.

“GlassLock is becoming an effective and cost attractive technique to segregate arsenic and is therefore opening new opportunities for arsenic-bearing precious metals deposits, concentrates or contaminated sites considered to contain too much arsenic to be exploited,” the company said.

This agreement is another major achievement in DST’s commercialisation efforts, it added.

Outotec addresses cyanide consumption with new BIOX refractory gold process

Outotec has introduced its new MesoTHERM BIOX process to significantly reduce cyanide consumption in refractory gold ore treatment.

Traditionally, cyanide consumption with conventional bio-oxidation residues is higher than with residues produced through other oxidative technologies. The Outotec MesoTHERM BIOX® process, based on Outotec’s existing mesophile BIOX process, offers an easy, cost-effective upgrade path that can cut cyanide consumption by as much as 50% compared with conventional bio-oxidation, the company claims.

The BIOX process, which has been in commercial operation for over 30 years, was developed for the pre-treatment of refractory concentrates ahead of conventional cyanide leaching for gold recovery.

“The Outotec MesoTHERM BIOX process enhances the established mesophile BIOX process by combining mesophile bio-oxidation technology with a higher-temperature thermophile oxidative stage to enable an even more effective overall sulphide oxidation step,” Outotec says.

On top of cutting cyanide consumption by as much as 50% compared with conventional bio-oxidation, MesoTHERM BIOX significantly reduces the formation of thiocyanate – a common and stable cyanide species traditionally formed as a further by-product, the company said.

Solubilised species prevalent in the mesophile stage are decanted off in an inter-stage thickening step between the two oxidative processes, simplifying operation of the thermophile stage, the company explained.

For existing BIOX customers, upgrading to BIOX MesoTHERM is a “relatively simple process”, Outotec says. It involves reconfiguring the circuit with the addition of Outotec’s High Rate Thickeners for inter-stage thickening and Outotec OKTOP® Atmospheric Reactors for the thermophile step.

Craig van Buuren, Senior Process Engineer, Outotec, said: “Our conventional mesophile BIOX process has enabled the production of over 25 Moz of gold to date. This novel process takes advantage of these proven technologies to help our customers achieve significant cost savings while also reducing their environmental footprint.”

Modernising last-generation geo-metallurgy practices

By Wolfgang Baum*

Dan Gleeson wrote in International Mining April 2020, “…near identical flowsheets have remained the status quo for decades, with the only variation tending to be how many pieces of conventional equipment are used, as opposed to what new innovations are slotted in up- or downstream of primary crushing”.

It is puzzling that, in many mining companies (and the EPCM world), the ore characterisation status quo has also remained the same since the 20th century ended. Robust ore profiling via modern quantitative laboratory technology is spotty at best or frequently outsourced to commercial labs. Models continue to be filled with too much visual data and lack sufficient quantitative process-related details. Hand lens and pocket knives or other qualitative tools prevail, while we try to utilise Big Data analytics.

Geo-metallurgy, the most overused word in mining, lingers on without emphasising the heart and essence of geology and metallurgy, ie modern ore characterisation focused on processing and based on instrumental laboratory work.

The current situation in ore characterisation is reminiscent of the US steel industry, post-World War II: the status quo remained with companies bound to familiar technology. When ‘big steel’ removed its blinders, the industry and technology had changed. Geo-metallurgical work, if it is to make meaningful improvements in future mining, requires ‘Ctrl-Alt-Delete’ followed by some seismic optimisations.

The low-hanging fruit has been harvested and future orebodies will not forgive one metallurgical mistake. A paradigm shift is needed toward robust continuous ore profiling (chemical, mineralogical and metallurgical). And, routine ore characterisation has to range from the blast holes and draw points, to the rougher and final tailings.

The few positive exceptions

Of course, a few exceptions stand out and need to be applauded.

Several mining companies have implemented and advanced cutting-edge laboratory technology and lab automation, built 24/7 central laboratories and continue to modernise ore characterisation in the direction of cross-belt analysis, downhole logging and large-scale orebody profiling.

Yet, these are exceptions, not the rule.

  • From 15 new copper concentrators built during the last 12 years, only +/- 14% had mineralogical lab capabilities on site. This contributes to delays in reaching nameplate capacity, more downtime and ‘noisy’ metallurgy; and
  • In 2018, only +/- 50% of the 10 largest copper producers and only +/-25% of the 10 largest gold producers had significant modern laboratory automation and process mineralogy labs at mine sites.

Too often, lab work has been minimised, de-prioritised and/or run as shortcuts by many mining companies.

  • Block models continue to be overloaded with geochemical data and a lack of sufficient quantitative mineralogy;
  • Operators wonder why they did not receive a warning from the mine geology department that the swelling clay content increased by 4%;
  • Most modern haul trucks may have over 200 sensors, yet most mines lack a cutting-edge mineralogy lab;
  • In 1973, Don Hausen pioneered the use of large-scale XRD (X-ray Diffraction) alteration contouring in Arizona. Forty-seven (47!!) years later, feet are still being dragged on installing routine XRD equipment for mine geology and processes;
  • Heap leaching in copper (and some other metals) continues to be challenged by wrong placement of ore, leach test coding errors, over- and under-crushed and over- and under-cured feed, poor agglomeration, high acid consumption or inconsistent acid addition, scattered permeabilities and permeability failures;
  • Many permeability failures in heap leaching were caused by a lack of geological ore control, missing quantitative clay data, ore blending based on visual logging, and/or poor leach practices;
  • Visual diagnostics are the most inadequate tool for identifying and monitoring detrimental minerals such as talc, pyrophyllite, swelling clay, hornblende, zeolites, acid consumers, pH–changing minerals to name a few; and
  • Finding out, post-start-up, that the mine has a poor hardness, pyrite or clay model should not be acceptable in the third decade of the 21st century.

Not modernising last generation laboratories imperils mining from pit to plant, and is one reason for underperforming flowsheets.

Having a few dump trucks or conveyors misrouting ore in large, integrated copper stockpile leach/heap leach/concentrator operations with molybdenum by-products may result in rapid compounded losses in the multimillion-dollar range.

Pushing tonnage (‘tonnage farming’) has its place, but, without concurrent good ore characterisation, it can be a high risk to optimal metallurgy.

For geo-metallurgy, labs are not everything – but they are an extremely important thing.

The plant does not see assay Cu, it sees minerals and textures!!

If modern ore characterisation had been used as part of an integrated geo-metallurgy program at many mine sites, there would have been significantly less of the issues listed below – most of which are related to lack of mineralogy data and continue to drain money from many mines:

  • Excessive frothing;
  • Over-reagentising;
  • Reagent pyramiding;
  • Permeability failures;
  • Undersizing of cleaners;
  • Higher pyrite dilutions;
  • Inconsistent feed size;
  • Runaway float conditions;
  • Self-floaters being out of control;
  • Unexpected changes in PSD;
  • More oxide molybdenum than modelled;
  • Oxide ore sent to concentrator;
  • High clay affecting mill loading;
  • Higher clay content than modelled;
  • Lack of control of acid consumers;
  • Excessive salting in heap leaching;
  • Increased wear through clay in high pressure grinding rolls;
  • Higher self-floaters = increasing smelting cost;
  • Feed rate variance 12-35% = incorrect mill sizing;
  • Higher acidic gangue = xanthates become ineffective;
  • Uncontrolled clay/mica/chlorite = sluggish molybdenum float;
  • Reduced grinding efficiency – packing of clays in lifters;
  • Excessive sliming = problems with cleaner scalper function;
  • Contaminated recycle water – higher O/F turbidity – U/F density issues; and
  • Poor selectivity, brittle froth, gangue entrainment and too much pH variance.

The cost of the above ‘issues’ may be in the hundreds of millions of dollars range.

Fire prevention, (modern lab technology at mine sites) on the other hand, is cost efficient

A heap failure due to clay variance can cost upwards of $15 million, in some cases, whereas unplanned concentrator shutdowns due to de-bottlenecking and tailings losses can prove even more expensive.

Ore misrouting, one of the larger loss factors due to a lack of routine process-related ore characterisation, may increase with deeper pits, more underground operations, longer hauling/conveying and higher strip ratios.

Big Data analytics requires ‘large-spatially-gridded-sampling’ and quantitative mineralogical and chemical characterisation of these samples. Anything short of this, despite the assumed cost savings, remains risky over-simplifications which lead to ‘speculative models’. Efficient geo-metallurgy will start when we enter process-related ore characterisation data into the models.

In regard to cost-cutting of on-site laboratory services, it’s just like in the nautical business – you can’t keep your sails trimmed forever. Future geo-metallurgy efforts would benefit from an assessment of ‘lessons ignored’.

*Wolfgang Baum is Managing Director of Ore & Plant Mineralogy LLC

DST’s CLEVR Process ups gold extraction yields in metallurgical test work

Dundee Sustainable Technologies (DST) has hit a new milestone, with results from metallurgical testing on mineralised samples from a top tier gold producer achieving extraction yields of up to 95.6% with the help of its cyanide alternative CLEVR ProcessTM.

DST received a circa-10 kg sample of material from an operating gold mine in South America, with the company mandated by the producer to conduct a metallurgical test program at its facilities in Thetford Mines, Canada. The objective was to define and quantify the gold extraction amenability of the CLEVR Process on the provided material.

In May 2020, DST completed the metallurgical test program and says the direct application of the CLEVR Process on the producer’s sample achieved gold extraction yields of up to 95.6%. Given the low sulphide concentration of the sample, no oxidation was necessary before proceeding to the CLEVR Process leaching step, it noted.

The method used by DST uses no cyanide, produces no toxic liquid or gaseous effluent, and the solid residues are inert, stable and non-acid generating, according to the company.

“The direct CLEVR Process leaching, without any pre-treatment, was successful and demonstrated higher gold extraction yields (>90%) when compared with cyanidation (67.6%) tests conducted on the same material,” the company said. “DST’s standard CLEVR Process conditions were utilised, which allowed for superior gold yields in a fraction of the time (one-hour leaching time).”

In addition, the solid tailings residues produced by the CLEVR Process met the US Environmental Protection Agency’s Toxicity Characterisation Leaching Procedure and may be considered as non-hazardous waste products, DST explained.

“DST is very excited with the results obtained using the CLEVR Process and the collaboration with the producer,” the company said. “The corporation will continue its development efforts with the producer to further develop this promising opportunity and the technical and economic parameters of DST’s Technology.”

In March 2020, DST tested two distinct lots of circa-50 kg and circa-30 kg samples of representative material from a gold miner’s operating mine in the Asia-Pacific region. The laboratory metallurgical test program showed the direct application of the CLEVR Process on oxidised samples achieved gold extraction yields of 93.5% and 94.2%, respectively, for the distinct lots tested.

Outotec upgrades ‘state-of-the-art’ process simulation package

Outotec says it has upgraded its HSC Chemistry® process modelling platform with new features, faster operation, and an improved user interface.

Outotec HSC Chemistry is widely used in the metallurgical and chemical industry and universities for R&D, process design and training workshops, according to Outotec, with the latest version being the result of more than 50 years of development, hundreds of hours of discussions with end users and decades of industry experience.

“It is truly a state-of-the-art process simulation package that seamlessly integrates into the wider metallurgical and chemical engineering process design environment,” the company said.

Metallurgical and chemical process technology must always be tailored to the local raw materials, energy sources and legislation, as the ores and secondary raw materials are unique at every site, Outotec says.

“Process flowsheet modelling is the basic tool, which makes it possible to optimise process recoveries, grades, OPEX, CAPEX, KPI guarantees, engineering data, environmental footprints, etc,” the company added.

The HSC Sim module is able to simulate the whole lifecycle of metals and chemicals including mineral processing, smelting, hydrometallurgical refining, precious metals recovery, and recycling, according to Outotec. “With HSC, a process designer can create a competitive and sustainable process.”

HSC LCA (Life Cycle Assessment) tools make it possible to understand and optimise the process, not only from the technical and economic point of view, but also considering the environmental impact. “It is critical to do this at the process design stage as it is difficult and expensive, if not impossible, to make changes after the engineering, construction, and start-up stages,” Outotec says.

HSC also acts as a basic R&D tool, which decreases the amount of expensive trial-and-error chemistry, Outotec says. “The experiments can be wisely designed before costly laboratory and pilot test campaigns. HSC also provides a lot of benefits in the analysis stage of the research work, and finally converts valuable experimental results into an easy to use digital format,” the company said.

Universities widely use HSC in workshops, because HSC offers versatile tools for various stages of education, according to Outotec. “Methodological skills related to modelling and simulation create connections between theory and practice, which helps students to understand the role and relevance of theoretical studies when they have a chance to apply their theoretical knowledge in real-life related problems using tools that are actually used in R&D projects.”

The HSC 10 top new features, according to Outotec, include:

  • New subscription-based licensing replaces old perpetual licensing;
  • HSC 9 calculation module files are upward compatible with the new HSC 10;
  • Sim Model Base expands personal expertise to organisation expertise;
  • Sim Model Optimization with Monte-Carlo, PSO, Simplex, MFit (SQP);
  • Sim Model Convergence Monitor for static models;
  • Sim Dynamic Report is a new tool for collecting simulation data;
  • Sim file loading and calculation speed improvements;
  • Sim Unit Operation Protection;
  • Sim model combination improvements;
  • Sim OpenLCA dialog improved and updated;
  • Sim new generic unit operations;
  • Gem Equilibrium Module: Own Pitzer parameters, electrode potential calculations;
  • Aqua Module with own Pitzer database;
  • New Sampler Module with save/open features;
  • Diagram Navigator Module: new triangulation algorithm and several small improvements;
  • Data Processing Module with new algorithms and faster graphics;
  • Material Database Module with links to location maps;
  • HSC Main Database Module with new and updated data for chemical species; and
  • HSC Main Menu with Sub Menu.

Outotec celebrates 70 years of technology innovation at Pori ORC

Outotec is, this week, celebrating 70 years of sustainable technology development at its Outotec Research Centre (ORC) in Pori, Finland.

The ORC in Pori is unique in the industry, according to the company, with its expertise in the minerals and metals processing value chain ranging from ores to finished metals and recycling.

The centre was established in 1949 and, since then, has been a part of the company’s long-term research and development strategy. The company is holding a two-day seminar to celebrate 70 years of process development on October 15–16, with speakers including leading researchers, professors and industrial influencers.

One of several cutting-edge technologies developed at the ORC is Outotec Flash Smelting, which is still one of the world’s most commonly used processes to produce primary copper and nickel. This innovation was developed at the ORC at the end of 1940s.

The centre’s laboratories conduct tests on raw materials for Outotec’s customers and the related production processes. Current testing capabilities include nine laboratories and pilot plants, with, annually, some 200 research projects conducted, and more than 250,000 samples analysed.

Outotec said: “There is a genuine need for continuous development of processes since ore deposits are becoming leaner in grade and more difficult to utilise. The conventional methods are often insufficient to make them financially viable. Outotec’s research centre in Pori supports customers in selecting and, if necessary, developing new solutions for the efficient and environmentally sustainable extraction of valuable minerals from raw materials.”

The company said it can take decades for a completely new technology to establish itself in the market, but once the technology platform is developed, new applications may quickly be found. This has happened to cobalt and lithium processing technologies in recent years with the electrification of transport, it said.

Jarkko Partinen, Vice President, Technology and R&D at the ORC, said the cobalt extraction technology developed in Pori back in the 1960s is, today, gaining in importance due to the advent of electric transport.

“Thanks to our continuous research and development work, we are able to offer customers new and efficient ways of processing materials such as battery chemicals,” he added.

Kalle Härkki, Head of Outotec’s Metals, Energy & Water business area, said Outotec’s customers each face unique challenges and it is the company’s job to create solutions that help them succeed.

“We are proud of our process and technology expertise, and having our own research centre is a competitive strength,” he said. “ORC has been characterised by research into environmental protection, the circular economy, and resource efficiency before any of these topics became mainstream. One of the earliest studies, which dates back to 1951 and would nowadays be linked to the circular economy, examined useful applications for sulphur gas roasting residues.”

ORC employs 180 research and development professionals, 45 of which are process and technology development engineers, half of whom hold a doctorate level degree. There is a dedicated group working in modelling and digitalising process expertise.

The laboratories employ more than 100 professionals most of them working in three shifts specialised in building and maintaining test rigs and equipment, conducting the test work planned by the process development engineers, and analysing samples taken from the tests.

In 2018, the ORC welcomed more than 1,300 visitors, the vast majority of which were customers, researchers and people attending training.

GoGold signs up BQE Water for SART plant at Parral tailings operation

BQE Water says it has been retained by GoGold Resources for the implementation of a sulphidisation, acidification, recycling and thickening (SART) plant at the Parral operation in Chihuahua, Mexico.

The contract comes after on-site testing and preliminary assessment of SART integration into the metallurgical process at Parral that were completed earlier by BQE Water.

Under the contract, BQE Water’s scope of work will include plant engineering design, process automation, engineering support during procurement and construction, plant commissioning, and ongoing operations support after plant start-up. The plant construction is expected to be completed by the end of the year. Once the plant is commissioned, BQE Water will provide operations support services for a monthly fee for a period of three years, it said.

Owned and operated by GoGold Resources, the Parral project involves the reprocessing of old tailings to recover silver and gold by conventional cyanidation. In addition to the precious metals, the tailings also contain significant quantities of cyanide soluble copper and zinc. These base metals compete for cyanide, causing high cyanide consumption and increasing operating costs, according to BQE.

Anis Nehme, COO of GoGold Resources, said: “We have been working with BQE Water for the past few years to evaluate SART integration into the Parral project and we are relying on their expertise to help us maximise the positive contribution SART can bring to the project’s overall performance.”

David Kratochvil, President & CEO of BQE Water, said: “This contract is further proof of our leadership in the safe, cost-effective and rapid deployment of SART to help precious metals producers improve the metallurgical and environmental performance of their projects.

“We stand behind our proven process designs perfected over multiple large projects completed in the past decade and in our operations support capabilities to ensure SART benefits are maximised while operational risks are minimised.”

The SART process recovers copper from cyanide leach solution while allowing free cyanide to be recycled back to the leaching of precious metals. This lowers the cost of gold extraction and reduces the environmental footprint of gold mining projects, BQE says.

“SART can be a game changer that favourably shifts project economics and enables projects to move forward,” BQE said, adding that fewer than 10 industrial scale SART plants have been built and operated globally.