Tag Archives: copper

Rio, Turquoise Hill put forward coal power plant option for Oyu Tolgoi

Rio Tinto says it is continuing to progress options to secure domestically sourced power for its majority-owned Oyu Tolgoi copper mine in Mongolia.

The mining major’s domestic search for energy is part of an obligation to source power by June 30, 2023 under the 2009 Investment Agreement between Turquoise Hill Resources (which owns 66% of Oyu Tolgoi), the Government of Mongolia and Rio Tinto, and the subsequent Power Sector Framework Agreement signed in 2018.

In compliance with these agreements, Oyu Tolgoi LLC has submitted to the Government of Mongolia a feasibility study for the Tavan Tolgoi Power Plant (TTPP) project, which involves building a 300 MW coal power plant. This plant, to be located in Tsogttsetsii soum of Umnugovi province, comes with a total project cost estimate of up to $924 million, pending consideration of certain amounts yet to be finalised, Turquoise Hill said. Rio says this amount is already included in the group capital expenditure guidance of $7 billion in 2020 and $6.5 billion each in 2021 and 2022.

In parallel with the TTPP project, and in consultation with the Government of Mongolia, Rio Tinto is also progressing alternative options to source domestic power, including a renewable power component, Rio said.

Oyu Tolgoi is currently sourcing power from China’s Inner Mongolian Western Grid via overhead power lines, via a back-to-back power purchase agreement with National Power Transmission Grid JSC, the power importing entity, and the Inner Mongolian Power Company, according to Turquoise Hill.

Rio Tinto Copper & Diamonds Chief Executive, Arnaud Soirat, said: “Rio Tinto, Turquoise Hill and the Government of Mongolia are all committed to securing a reliable and long-term domestic power source for the Oyu Tolgoi mine and are working together to achieve this.”

Teck renews carbon reduction goals with help of AES

Teck Resources, AES Corp and their respective Chile-based affiliates, Compañía Minera Teck Quebrada Blanca SA and AES Gener SA, have entered into a long-term power purchase agreement for the Quebrada Blanca Phase 2 (QB2) copper project in Chile, which will enable the transition to renewable energy for around half the power required for the operation.

Under this arrangement, CMTQB will source 118 MW for Quebrada Blanca Phase 2 from AES Gener’s growing renewable portfolio of wind, solar and hydroelectric energy, in addition to the 21 MW of solar power already contracted from AES Gener. Once effective, more than 50% of QB2’s total operating power needs are expected to be from renewable sources, Teck said.

The transition to renewable power will replace QB2’s previous fossil fuel power sources, avoiding some 800,000 t/y of greenhouse gas emissions. “That is equivalent to the emissions of about 170,000 combustion engine passenger vehicles – equal to permanently parking more than half of all the cars in the City of Vancouver, or all the cars in the Tarapacá Region of Chile where QB2 is located,” Teck said.

The renewable power arrangement will come into effect as early as January 2022 and will run through October 2042. CMTQB’s other arrangements with AES Gener, totaling 122 MW of power, are not impacted, Teck said.

Don Lindsay, President and CEO of Teck, said: “Switching to renewable power for QB2 is part of Teck’s ongoing work to reduce emissions, achieve carbon neutrality across our business and support global action on climate change. This agreement secures reliable, long-term power for our major copper growth project at no additional cost, while helping to reduce our environmental footprint.”

Lindsay said the company would continue to explore further opportunities to increase the use of renewable energy as part of Teck’s ongoing focus on decarbonisation.

Andrés Gluski, President and CEO of AES, said: “We are proud to work with our customers in the transition to a low-carbon energy future. We have a long-term relationship with Teck and are happy to support their evolving energy needs.”

Ricardo Manuel Falú, AES Gener’s Chief Executive Officer, said: “At AES Gener, we are contributing to the mining sector’s goal of being more sustainable while supporting the decarbonisation of the Chilean energy matrix. With our Greentegra strategy and our Coal to Green solution, we enable our customers to become greener and more competitive by replacing coal-based energy sources with renewables.”

The $4.74 billion project is expected to produce 316,000 t/y of copper-equivalent for the first five full years at all-in sustaining costs of $1.38/Ib ($3,043/t). The initial mine life of 28 years uses less than 25% of the current reserve and resource, according to Teck and, based on a $3/Ib average copper price over the life of the mine, QB2 is expected to provide a net present value (8% discount) of $2.43 billion.

In addition to renewable power, QB2 will also feature the first large-scale use of desalinated seawater for mining in the Tarapacá Region of Chile, in place of freshwater use.

The QB2 announcement comes at the same time as Teck announced a goal of becoming carbon neutral across its operations and activities by 2050.

“This objective builds on Teck’s progress on climate action to date, including implementing projects and initiatives to reduce GHG emissions at its operations by 289,000 t since 2011 – the equivalent to taking over 88,000 combustion engine cars off the road – and 81% of Teck’s current total electricity consumption is from renewable energy sources.”

AES is also committed to reducing its carbon intensity by 50% by 2022 and 70% by 2030, compared with a 2016 baseline. Aligned with that goal, AES Gener is leading the decarbonisation efforts in Chile, with the largest amount of renewable energy capacity under construction in that country, according to Teck.

OK Tedi boosts operator safety with new Immersive Technologies collaboration

Immersive Technologies and OK Tedi have established the first fully-integrated Operator Performance Analytics (OPA) system as part of the Papua New Guinea miner’s focus on operator safety, Immersive says.

Following the successful delivery of continuous improvement projects and managed services by Immersive, OK Tedi opted to establish an OPA installation on-site with the dual goals of improving safety and machine care among their operators, Immersive, which is now part of Komatsu Ltd, said.

Using the OPA electronic operator scorecard, OK Tedi was able to drill down to individual operator performance indicators. These indicators can be used to see how an operator compares with their peers or are trending over time. “Ranking of all operators additionally provides a unique opportunity to motivate personal ownership of safety statistics and performance, while providing management an effective tool to identify training needs to improve overall mine site productivity,” Immersive said.

OPA data can also be filtered specific to machine errors, performance on different machines, performance over time and training history to locate the root cause of a performance trend. An initial dataset was analysed using six months of machine operational data from the field and simulator data, with this data used to identify outlier operators in terms of risk rating or performance against key metrics (such as spot time, average speed loaded and average tonnes per km/h).

Masket Siune, Superintendent Mine Business Improvement & Training OK Tedi, said: “OPA has enabled quicker analysis of mine operator performance to identify trends or patterns to mitigate risk relating to equipment reliability and operator productivity metrics.

“We now have a reliable operator data platform that gives real comprehensive data view to approach our operators and discuss training development needs or for reward and recognition for the outstanding performance based on both risk and productivity criteria.”

With multiple operational data sources integrated within OPA, OK Tedi easily identified a high incidence of high peak frame bias events, therefore prioritising simulator training for those operators contributing the highest error counts, Immersive said. Once underperforming operator groups or individuals are identified, these can be selected and assigned to a training needs analysis report.

Simulator training can then be conducted and training data automatically sent back to OPA —without manual intervention. Typical training scenarios for errors could require operators to navigate loaded trucks over rough road conditions or load and dump using the correct procedure. In turn, this can be used for assessment of training retention and impact.

Alex Da Silva, Global Professional Services Manager at Immersive Technologies, said: “At OK Tedi, analysis that previously took days or weeks, now takes minutes, integrating disparate data systems with simulator generated data provides a single, powerful platform for workforce development planning.”

OK Tedi, which mines copper, gold and silver in the Western province of PNG, plans to extend the use of OPA to additional machines types to further support its operations, according to Immersive.

Redpath to deliver Pumpkin Hollow ramp-up, Nevada Copper says

Nevada Copper has engaged mining contractor Redpath USA to implement its ramp-up strategy for its underground copper mine at Pumpkin Hollow, in Nevada.

The company commenced production at the underground mine in December and is now entering into a new phase of development supporting its ongoing operations. It said it has “high confidence” in Redpath’s ability as a partner during the ramp-up to full commercial production in 2020.

Redpath replaces the previous mining contractor and will be the company’s principal underground mining contractor going forward, Nevada Copper said. “Redpath is a highly experienced mining contractor with experience of delivering complex projects both internationally and in Nevada, ahead of schedule and under budget,” it added.

Matt Gili, Chief Executive Officer of Nevada Copper, said: “Nevada Copper made the transition to producer in Q4 (December quarter) 2019 and we have developed a clear, straightforward strategy for ramping up our Pumpkin Hollow underground project to full commercial production. Redpath is considered throughout the mining industry as the partner of choice for production ramp up and we are excited to be working with them during this important period of growth.”

Nevada Copper has previously said it is focused on ramping up the mine, in Yerington, to reach nameplate capacity in the first half of 2020.

The 2017 prefeasibility study plan for the underground mine outlined a 5,000 t/d project able to produce some 50 MIb/y (22,680 t/y) of copper, 8,000 oz of gold and 150,000 oz of silver over a 13.5-year life at all-in sustaining costs of $1.96/Ib of copper. It also laid the foundations for a larger integrated project that includes open-pit development and could increase throughput to 70,000 t/d.

Outotec and Neste to introduced bio-based diluent to metals extraction sector

Outotec says it and Neste have jointly verified the viability of applying a bio-based diluent as a new solution for metals extraction.

Neste MY Renewable Isoalkane™ is a fully bio-based diluent for extracting metals in hydrometallurgical processes, Ouotec said, explaining that the diluent is based on Neste’s NEXBTL technology and produced entirely from bio-based waste and residue raw materials.

Laboratory studies and pilot trials at the Outotec Research Center in Pori, Finland, and Neste’s Technology Center in Porvoo, Finland, have confirmed the high-level performance of the product for solvent extraction of copper, and it can be also used for other base metals, according to Outotec.

“Thanks to its renewable origins and being readily biodegradable, the bio-based diluent reduces environmental risk and has a remarkably smaller carbon footprint over its life cycle when compared to fossil equivalents,” Outotec said. Moreover, Neste MY Renewable Isoalkane evaporates at a lower rate, which improves copper extraction efficiency and safety due to significantly reduced volatile organic compounds, the company added.

Neste MY Renewable Isoalkane is fully compatible with conventional fossil diluents at solvent extraction plants, and can be introduced into the extraction process without any downtime, Outotec said.

Kari Knuutila, Chief Technology Officer at Outotec, said: “This cooperation with Neste is part of our continuous innovation efforts of improving the environmental performance of our technologies and helping our customers to meet their sustainability goals. In this project, experts from two industries discovered synergies and co-created a new application for Neste’s bio-based product.”

Mercedes Alonso, Executive Vice President, Renewable Polymers and Chemicals at Neste, said: “Using Neste MY Renewable Isoalkane as a replacement to fossil diluents provides significant ecological benefits, while simultaneously improving the efficiency, economy and safety of metals extraction processes.”

Outotec and Neste have agreed to cooperate in introducing the Neste MY Renewable Isoalkane to metal producers. Outotec will provide technical industry expertise, whereas Neste will be responsible for the production, sales and deliveries of the bio-based diluent to the solvent extraction sites globally.

Panoramic looks to Barminco for Savannah nickel-copper-cobalt ramp up

Perenti’s hard-rock underground mining subsidiary, Barminco, has been selected as the preferred contractor by Panoramic Resources at its Savannah nickel-copper-cobalt project in the Kimberley region of Western Australia.

The contract, worth around A$200 million ($135 million), will see Barminco carry out mine development, production, and haulage over a three-year term. Work is expected to commence in March 2020.

Barminco anticipates it will employ around 170 people for the project and use predominately new equipment, which has been included in the capital guidance previously provided, to deliver the project.

Savannah, 110 km north of Halls Creek in Western Australia, saw mining operations recommence in December 2018, with the first shipment of concentrate departing Wyndham in February 2019. The miner is currently developing the higher-grade Savannah North orebody focusing on high speed development and a ramp up to full production in 2020, Perenti said.

Perenti Managing Director, Mark Norwell, said: “This project demonstrates our ability to capture organic growth opportunities, with the Barminco business now well integrated into the Perenti group whilst further embedding itself as a leader in underground mining.”

Underground Chief Executive Officer, Paul Muller, added: “We look forward to working closely with Panoramic Resources in driving the development of the Savannah North orebody safely and efficiently as it ramps up to full production.”

Miners need to do more in climate change, decarbonisation battle, McKinsey says

A report from consultancy McKinsey has raised concerns about the mining industry’s climate change and decarbonisation strategy, arguing it may not go far enough in reducing emissions in the face of pressure from governments, investors, and activists.

The report, Climate risk and decarbonization: What every mining CEO needs to know, from Lindsay Delevingne, Will Glazener, Liesbet Grégoir, and Kimberly Henderson, explains that extreme weather – tied to the potential effects of climate change – is already disrupting mining operations globally.

“Under the 2015 Paris Agreement, 195 countries pledged to limit global warming to well below 2.0°C, and ideally not more than 1.5°C above preindustrial levels,” the authors said. “That target, if pursued, would manifest in decarbonisation across industries, creating major shifts in commodity demand for the mining industry and likely resulting in declining global mining revenue pools.”

They added: “Mining-portfolio evaluation must now account for potential decarbonisation of other sectors.”

The sector will also face pressure from governments, investors, and society to reduce emissions, according to the authors.

“Mining is currently responsible for 4-7% of greenhouse gas (GHG) emissions globally. Scope 1 and Scope 2 CO2 emissions from the sector (those incurred through mining operations and power consumption, respectively) amount to 1%, and fugitive methane emissions from coal mining are estimated at 3-6%.

“A significant share of global emissions – 28% – would be considered Scope 3 (indirect) emissions, including the combustion of coal.”

While there have been a number of high-profile mining companies making carbon emission pledges in the past 18 months – BHP pledging $400 million of investment in a low carbon plan being one notable example – the authors say the industry has only just begun to set emissions-reduction goals.

“Current targets published by mining companies range from 0-30% by 2030, far below the Paris Agreement goals, which may not be ambitious enough in many cases,” they said.

Through operational efficiency, and electrification and renewable-energy use, mines can theoretically fully decarbonise (excluding fugitive methane), according to the authors, with the disclaimer that building a climate strategy, “won’t be quick or easy”.

Water/heat

Water stress was one area the authors homed in on, saying that climate change is expected to cause more frequent droughts and floods, altering the supply of water to mining sites and disrupting operations.

The authors, using McKinsey’s MineSpans database on copper, gold, iron ore, and zinc, recently ran and analysed a water-stress and flooding scenario to emphasise the incoming problems.

The authors found that 30-50% of the production of these four commodities is concentrated in areas where water stress is already “high”.

“In 2017, these sites accounted for roughly $150 billion in total annual revenues and were clustered into seven water-stress ‘hot spots’ for mining: Central Asia, the Chilean coast, eastern Australia, the Middle East, southern Africa, western Australia, and a large zone in western North America,” the authors said.

The authors continued: “Climate science indicates that these hot spots will worsen in the coming decades. In Chile, 80% of copper production is already located in ‘extremely high’ water-stressed and ‘arid’ areas; by 2040, it will be 100%. In Russia, 40% of the nation’s iron ore production, currently located in ‘high’ water-stressed areas, is likely to move to ‘extreme’ water stress by 2040.”

And, mining regions not accustomed to water stress are projected to become increasingly vulnerable, according to the report.

By 2040, 5% of current gold production likely will shift from ‘low–medium’ water stress to ‘medium–high’; 7% of zinc output could move from ‘medium–high’ to ‘high’ water stress, and 6% of copper production could shift from ‘high’ to ‘extremely high’ water stress.

The authors said: “Depending on the water-intensiveness of the processing approach, such changes, while seemingly minor in percentage terms, could be critical to a mine’s operations or licence to operate.”

Mining executives in these regions are acutely aware of the water issue, according to the authors.

“For instance, Leagold Mining recently shut down its RDM gold mine in Brazil for two months because of drought conditions, even though it had built a dam and a water pipeline,” they said.

Even in areas with low water stress, certain water-intensive mining processes are jeopardised.

“In Germany – not a country known for being vulnerable to drought – a potash miner was forced to close two locations because of severe water shortages in the summer of 2018, losing nearly $2 million a day per site,” they said.

“The frequency and severity of these conditions are expected to increase along with the current climate trajectory.”

To improve resiliency, companies can reduce the water intensity of their mining processes, the authors said. They can also recycle used water and reduce water loss from evaporation, leaks, and waste. Mining companies can, for example, prevent evaporation by putting covers on small and medium dams.

In the long term, more capital-intensive approaches are possible, according to the authors. This could involve new water infrastructure, such as dams and desalination plants. Companies can also rely on so-called “natural capital”, like wetland areas, to improve groundwater drainage.

The authors said: “The option of securing water rights is becoming harder and can take years of engagement because of increased competition for natural resources and tensions between operators and local communities. Basin and regional planning with regulatory and civic groups is an important strategy but cannot alone solve the underlying problem of water stress.”

On the reverse, flooding from extreme rains can also cause operational disruptions, including mine closure, washed-out roads, or unsafe water levels in tailing dams, with flooding affecting some commodities more than others based on their locations.

The authors’ analysis showed iron ore and zinc are the most exposed to ‘extremely high’ flood occurrence, at 50% and 40% of global volume, respectively.

“The problem is expected to get worse, particularly in six ‘wet spots’ likely to experience a 50-60% increase in extreme precipitation this century: northern Australia, South America, and southern Africa during Southern Hemisphere summer, and central and western Africa, India and Southeast Asia, and Indonesia during Southern Hemisphere winter,” the authors said.

Companies can adopt flood-proof mine designs that improve drainage and pumping techniques, the authors said, mentioning the adaptation of roads, or the building of sheeted haul roads, as examples.

Moving to an in-pit crushing and conveying method would also help alleviate potential floods, replacing mine site haulage and haul roads with conveyors.

When it comes to incoming extreme heat in already-hot places – like China, parts of North and West Africa and Australia – the authors noted that worker productivity could fall and cooling costs may rise, in additon to putting workers’ health (and sometimes their lives) at risk.

“Indirect socioeconomic consequences from climate change can also affect the political environment surrounding a mine,” they said.

Shifting commodity demand

Ongoing decarbonisation is likely to have a major impact on coal – “currently about 50% of the global mining market, would be the most obvious victim of such shifts”, the authors said – but it would also affect virgin-ore markets.

“In a 2°C scenario, bauxite, copper, and iron ore will see growth from new decarbonisation technologies offset by increased recycling rates, as a result of the growing circular economy and focus on metal production from recycling versus virgin ore,” they said.

At the other end of the spectrum, niche minerals could experience dramatic growth. As the global electrification of industries continues, electric vehicles and batteries will create growth markets for cobalt, lithium, and nickel.

Emerging technologies such as hydrogen fuel cells and carbon capture would also boost demand for platinum, palladium, and other catalyst materials, while rare earths would be needed for wind-turbine magnets.

The authors said: “Fully replacing revenues from coal will be difficult. Yet many of the world’s biggest mining companies will need to rebalance non-diverse mineral portfolios.

“Many of the largest mining companies derive the bulk of their earnings from one or two commodities. Copper-heavy portfolios may benefit from demand growth due to widespread electrification, for example. And iron ore- and aluminium-heavy portfolios may see an upside from decarbonisation technologies, but they are also more likely to be hit by rising recycling rates.”

According to the authors, the mining industry generates between 1.9 and 5.1 gigatons of CO2-equivalent of annual greenhouse gas (GHG) emissions. Further down the value chain (Scope 3 emissions), the metals industry contributes roughly 4.2 gigatons, mainly through steel and aluminium production.

To stay on track for a global 2°C scenario, all sectors would need to reduce CO2 emissions from 2010 levels by at least 50% by 2050, they said.

To limit warming to 1.5°C, a reduction of at least 85% would likely be needed.

“Mining companies’ published emissions targets tend to be more modest than that, setting low targets, not setting targets beyond the early 2020s, or focusing on emissions intensity rather than absolute numbers,” the authors said.

To estimate decarbonisation potential in mining, the authors started with a baseline of current emissions by fuel source, based on the MineSpans database of mines’ operational characteristics, overlaid with the possible impact of, and constraints on, several mining decarbonisation levers.

The potential for mines varied by commodity, mine type, power source, and grid emissions, among other factors.

“Across the industry, non-coal mines could fully decarbonise by using multiple levers. Some are more economical than others – operational efficiency, for example, can make incremental improvements to the energy intensity of mining production while requiring little capital expenditure,” they said. Moving to renewable sources of electricity is becoming increasingly feasible too, even in off-grid environments, as the cost of battery packs is projected to decline 50% from 2017 to 2030, according to the authors.

“Electrification of mining equipment, such as diesel trucks and gas-consuming appliances, is only starting to become economical. Right now, only 0.5% of mining equipment is fully electric.

“However, in some cases, battery-electric vehicles have a 20% lower total cost of ownership versus traditional internal-combustion-engine vehicles. Newmont, for example, recently started production at its all-electric Borden mine in Ontario, Canada.”

The authors said: “Several big mining companies have installed their own sustainability committees, signalling that mining is joining the wave of corporate sustainability reporting and activity. Reporting emissions and understanding decarbonisation pathways are the first steps toward setting targets and taking action.”

Yet, these actions are currently too modest to reach the 1.5-2°C scenario and may not be keeping up with society’s expectations – “as increasingly voiced by investors seeking disclosures, companies asking their suppliers to decarbonise, and communities advocating for action on environmental issues”.

They concluded: “Mining companies concerned about their long-term reputation, licence to operate, or contribution to decarbonisation efforts may start to consider more aggressive decarbonisation and resilience plans.”

Freeport to invest in data science, AI programs at North/South America mines

After carrying out a successful pilot at its Bagdad copper operation, Freeport McMoRan says it is rolling out a program across its North America and South America mines involving the use of data science, machine learning and integrated functional teams.

The program, aimed at addressing bottlenecks, providing cost benefits and driving improved overall performance, was announced in its December quarter results this week.

It said: “During 2019, FCX (Freeport) advanced initiatives in its North America and South America mining operations to enhance productivity, expand margins and reduce the capital intensity of the business through the utilisation of new technology applications in combination with a more interactive operating structure.”

It said the Bagdad mine (Arizona, USA) pilot program, initiated in late 2018, was “highly successful” in utilising these innovative technologies and it would build on this for the implementation across its other mines in North and South America.

According to a report in the Financial Times, the system at Bagdad found that the mine was producing seven distinct types of ore and that the processing method, which involves flotation, could be adjusted to recover more copper by adjusting the PH level.

The company didn’t provide any details on who it was working with on this project, but confirmed at the back end of 2019 that the Bagdad trial was carried out with management consulting firm McKinsey.

In its investor presentation announcing its December results, the company provided a little more colour on these initiatives.

On the processing/concentration side, it was using a digital twin for processing plant, in tandem with a machine-learning algorithm. These used historical data to predict results and optimise throughput and recovery. In addition to this, the solutions were able to provide “quality recommendations”, aiding real-time data-driven decisions. This allowed the processing teams to target “best performance every day”, while unlocking bottlenecks and providing more consistent operations.

It was a similar story on the mine side. Data is being aggregated from multiple systems to help inform the data-science algorithms to predict the most efficient setups. It also sends commands to dispatch to adjust mining equipment and resource execution, allowing for clear visibility of the best possible performance for shift/day, again, effectively providing real-time decision making.

Under the title “agile way of working”, Freeport said it was promoting a more interactive organisational structure that will challenge norms and identify and prioritise opportunities as part of these initiatives.

CREDIT: Freeport McMoRan

Freeport continued: “A series of action items have been identified, prioritised and are being implemented. Based on the opportunities identified to date, FCX has incorporated higher mining and milling rates in its future plans, resulting in estimated incremental production of approximately 100 MIb (45,359 t) of copper in 2021 and around 200 MIb in 2022.”

Freeport said capital expenditures associated with these initiatives are expected to be “attractive” in relation to developing new copper supply, with the company estimating capital costs – principally associated with mining equipment and ongoing development of data science and machine-learning programs – of some $200 million.

Looking back at the quarterly production figures, it is easy to see the impact this trial had on Bagdad. In the March quarter of 2018, the mine produced 49 MIb of copper, with 48 MIb coming out in the June quarter of that year. It dropped to 45 MIb in the September quarter before stepping up to 57 MIb in the last quarter of that year (when the trial commenced). In the March quarter of 2019, output dipped slightly to 55 MIb, before heading back to 57 MIb in the June quarter and surpassing that (58 MIb) in the September quarter. Output fell back to 48 MIb in the most recent December quarter.

The Bagdad operation consists of a 75,000 t/d concentrator that produces copper and molybdenum concentrate, an SX/EW plant that can produce up to 32 MIb/y of copper cathode from solution generated by low-grade stockpile leaching, and a pressure-leach plant to process molybdenum concentrate.

Weir Cavex hydrocyclones take a load off at OceanaGold Didipio mine

The installation of 19 Cavex® 400CVX10 hydrocyclones at OceanaGold’s Didipio gold and copper mine in the Philippines has led to savings of more than $800,000/y through a dramatic reduction in grinding circuit recirculation, according to Weir Minerals.

The Didipio mine, which employs more than 1,500 workers (drawn predominantly from the local community), has expanded throughput over the last few years in line with its transition from open pit to underground mining. This increased the incumbent cyclones’ feed density beyond what they could effectively manage, leading to a circulating load of up to 700%, according to Weir.

The Cavex 400CVX10 hydrocyclones significantly improved separation efficiency due to their finely tuned spigot liner diameter and the strength and corrosion resistance provided by its cast housing, according to Weir.

Thanks to these qualities, the introduction of the Cavex hydrocyclones reduced the circulating load from 620% to 374%, with the direct savings in power consumption, ball consumption, cyclone and pump maintenance costs exceeding $815,000/y.

Gary Webb, Processing Manager, OceanaGold Didipio project, said: “Having had good performance from Cavex hydrocyclones at our New Zealand sites (Macraes and Waihi), we were confident that retrofitting Cavex hydrocyclone cluster at Didipio, with an increased number of smaller cyclones than we had at the time, would help reduce our problematic circulating load and lever multiple benefits in doing so.

“The changeover to Cavex hydrocyclones has exceeded our expectations, enabling higher throughput and lower consumable costs without being penalised in grind size.”

The performance of Cavex hydrocyclones can be attributed to the 360° laminar spiral inlet geometry design, which provides a natural flow path into the hydrocyclone, Weir said. This shape allows the feed to blend smoothly with rotating slurry inside the chamber, reducing turbulence.

Mike Arakawa, Philippines Country Manager, Weir Minerals, said: “Working with customers across the globe, our expert engineers are constantly looking at how they can maximise separation efficiency, hydraulic capacity and extend the wear life of not just the hydrocyclone, but our customers’ overall processing plants.

“I’m proud of the results we’ve achieved together with OceanaGold. Reduced circulation means reduced power draw, fewer balls consumed and less equipment wear, creating a more sustainable mine.”

Didipio produced 114,985 oz of gold and 14,999 t of copper in 2018, with 120,000-130,000 oz and 14,000-15,000 t of copper slated for 2019.

Enl Electrical focused on timely project deliveries in Africa

Enl Electrical, an electrical control and instrumentation specialist (EC&I) contractor, says its work on a large copper mine expansion project, in Zambia, is just one of many contracts it is delivering timely solutions for.

A member of the Zest WEG Group, Enl Electrical works extensively with project houses and directly for mining companies, and is a preferred supplier to many of them, according to the company.

Russell Drake, General Manager Operations at EnI Electrical, said: “Large project implementation is complex, and is often made more challenging by the logistical constraints that many African projects face. There are invariably delays at various stages, which places more pressure on the EC&I contractor, who must in many ways ‘complete’ the roll-out.”

Calvin Fisher, EnI Electrical Overhead Lines Manager, emphasises the importance of on-time completion, combined with reliable electricity supply: “With the various issues that may delay stages of a project, there is usually growing urgency as the deadline date approaches. This is normally when EnI Electrical enters the project, so we are accustomed to working under some extra pressure. Our dynamic team actively looks for ways to advance the work, especially when the previous phases may not be quite ready for us to begin.”

The linking up of electrical infrastructure, connections and equipment is one of the final stages to allow any project to start operating. In this role, EnI Electrical installs a wide range of electrical infrastructure including medium and low voltage cable reticulation, motor control centres, lighting, earthing protection and energy management systems.

Its control and instrumentation work ranges from process instrumentation and plant automation, to custom control stations and fibre or copper networks, it says. The company also designs and installs overhead power lines (up to 161 kV) and substations.

Drake said: “Our permanent bases in countries like Zambia and Ghana – with significant in-country investment in technical assets – underpins the efficiency of our work. We understand our working environment very well, so we can quote accurately and fairly. This is vital to reduce variations during projects, as this can be disruptive to the project and the client.”