MAY/JUNE 2021 VOLUME 4 ISSUE 4
HYDRANSAFE HFC-E 68
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CONTENTS 03
Guest Comment
05
World News
10
Responsible Sourcing In South America Andrew Britton and Timothy Perkin, Kumi Consulting, UK, explore the South American context and how evolving regulatory and market requirements for responsible sourcing will impact companies sourcing from the region.
28
Fight Fire With Functionality Pierre-Marie Maurice, David Kupiec, and Aimilia Neroutsou, Total, France, review a recent innovation in hydraulic fluids that is set to provide greater safety to the mining industry without compromising performance.
33
Points On Plug And Play Dr Thomas Paul, HUBER+SUHNER, and John Hooper, Ampcontrol, explain how plug and play is the future for reliable, secure mining connectivity and communications.
37
A Bridge To The Future Thiru Veeraraghavan, A.W. Chesterton Co., USA, provides insight into how using the Internet of Things for preventative maintenance can thwart pump and valve failures in aluminium processing.
41
15
20
Kevin Slemko, Major Drilling Group International Inc., Canada, outlines the process of supporting the delivery and ramp up of a new hydrofracking programme for Freeport Indonesia at the Deep Mill Level Zone mine.
Copper’s Challenges Gruffudd Roberts, CRU, UK, explores the challenges copper miners must navigate to bring on new supply in order to meet the world’s increasing demand.
45
Driving The World’s Largest Opencast Copper Mine
48
Neil Gordon, AirEng | The New York Blower Company, shares the benefits of remote condition monitoring and predictive maintenance for mine ventilation equipment.
Eliminating Negative Effects Wendel Rodrigues, Wagner Silva, Pierre Fernandes, Pedro Gonzaga, and Ronaldo Fonseca, Clariant, describe how using a new reagent suite can reduce the negative effects of aluminosilicate minerals on gold flotation.
ON THE COVER
MAY/JUNE 2021 MAY/JUNE 2021 VOLUME 4 ISSUE 4 VOLUME 4 ISSUE 4
HYDRANSAFE HFC-E 68
Total Lubrifiants has introduced the fire-resistant HYDRANSAFE HFC-E hydraulic fluid that not only reduces fire hazards in underground mining, but can also deliver higher equipment reliability. HYDRANSAFE HFC-E boasts four key features of hydraulic fluids: fire resistance, highly improved wear performance, non-toxicity, and biodegradability. For more information, email ms.industry.lub@total.com, visit lubricants.total.com, or search Total Industry Solutions on LinkedIn.
New New generation generation hydraulic hydraulic flfluid uid
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Fine-Tuning Flotation Dr Dariusz Lelinski, FLSmidth, USA, outlines how new approaches to flotation and froth recovery can cut coarse particle loss and increase efficiency.
53
Adding Value To Ventilation
Managing Productivity Peter Malmberg, Epiroc, Sweden, explains how inventory management can increase productivity.
Ulf Richter, ABB, Germany, outlines how gearless conveyor drives are powering the world’s largest opencast copper mine in Chile.
25
Stabilising Seismic Activity
ction Protteection ndd Pro y aan tty
Fire resistant Fire resistant
Mechanical Mechanical protection protection Biodegradable Biodegradable Non-toxicity Non-toxicity
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GUEST Comment
RICK VALENTA, ELEONORE LEBRE, JOHN OWEN, AND DEANNA KEMP SUSTAINABLE MINERALS INSTITUTE (SMI), THE UNIVERSITY OF QUEENSLAND
T MANAGING EDITOR James Little james.little@globalminingreview.com SENIOR EDITOR Callum O’Reilly callum.oreilly@globalminingreview.com DEPUTY EDITOR Will Owen will.owen@globalminingreview.com EDITORIAL ASSISTANT Jessica Casey jessica.casey@globalminingreview.com SALES DIRECTOR Rod Hardy rod.hardy@globalminingreview.com SALES MANAGER Ryan Freeman ryan.freeman@globalminingreview.com PRODUCTION Kyla Waller kyla.waller@globalminingreview.com ADMINISTRATION MANAGER Laura White laura.white@globalminingreview.com WEBSITE MANAGER Tom Fullerton tom.fullerton@globalminingreview.com DIGITAL EVENTS COORDINATOR Louise Cameron louise.cameron@globalminingreview.com DIGITAL EDITORIAL ASSISTANT Bella Weetch bella.weetch@globalminingreview.com GLOBAL MINING REVIEW (ISSN No: 2515-2777) is published by Palladian Publications Ltd. Annual subscription (monthly) £50 UK including postage, £60 overseas (airmail). Claims for non-receipt must be made within four months of publication of the issue or they will not honoured without charge.
he world is at a crossroads. Energy markets are being restructured to combat climate change and post-pandemic economic recovery planning is underway. Whichever way markets turn, record quantities of copper will be needed. With this in mind, analysts are signalling that unless there is a significant uptick in production, we’re headed for a ‘supply crunch’. This raises significant sustainability issues for copper. Future copper mines are projected to be lower grade, deeper, and more technically complex. Historical and projected copper metal production and ore grade from 1900 to 2050 highlights a continuation in the increase in production and decreasing grade, as innovation in the mining industry has allowed lower grades to be mined profitably. This combination of lower grade and greater depth means that many new mining projects will generate more waste rock, tailings, and deleterious elements – such as arsenic. If projected demand for copper is to be met, between 2000 to 2050, the SMI at the University of Queensland estimates that the world will produce approximately nine times the amount of copper tailings produced in the entire century prior. Copper’s sustainability challenges don’t stop there. New copper mines are more likely to be located in politically and ecologically sensitive areas. A recent global analysis of 300 undeveloped copper orebodies found that 65% of undeveloped reserves and resources are located in high water risk areas, 47% on or in close proximity to Indigenous peoples’ lands, 65% in areas located in or in close proximity to biodiversity conservation areas, and 50% in socially and politically fragile countries.1 Sustainability risks were also analysed in combination and high levels of ‘risk intensity’ were found, with 63% of global copper reserves and resources having four or more concurrent risks. Will a rise in the price of copper solve these sustainability issues? Evidence suggests that it will not. Mining companies rely on rising prices to address supply shortfalls. Higher metal prices drive companies to explore and operate in difficult locations, invest in infrastructure, and implement new mining technologies. Some of these technologies will support sustainability improvements, such as: waste and emissions reduction, recycling, and efficiencies in water and energy use. However, many sustainability risks are not price sensitive. For instance, in the contexts in which they operate, mining companies cannot pay their way out of biodiversity loss, extreme poverty, or corruption risk. If large numbers of undeveloped copper orebodies are rapidly brought into production in these contexts, local impacts will intensify, across multiple sites. Complex sets of impacts will be ‘baked’ into mining’s future legacy – often without clarity about who takes responsibility for them over the long term. If the copper industry simply ramps up, without looking at how mining could be done differently, operators could jeopardise supply. And if opposition to a proliferating set of local-level impacts grows, and supply stalls because of poor industry practice, so too will the clean energy transition. It’s going to be vitally important that copper producers do not gloss over copper’s sustainability challenges now, or in the future.
References 1.
VALENTA, R.K., KEMP, D., OWEN, J.R., CORDER, G.D., and LÈBRE, É., ‘Re-thinking complex orebodies: Consequences for the future world supply of copper’, Journal of Cleaner Production, (20 May 2019), www.sciencedirect.com/ science/article/pii/S0959652619305359
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WORLD NEWS
USA USA Rare Earth exercises option to acquire stake in Round Top Project
T
exas Mineral Resources Corp. (TMRC) has announced that, pursuant to the terms of the approved 2019 amended and restated option agreement, USA Rare Earth has fully funded its US$10 million commitment to earn its 70% interest in the Round Top heavy rare earth, lithium, and critical minerals project in Hudspeth County, Texas, and has exercised its option to acquire an additional 10% of the Round Top Project. As a result of the performance by USA Rare Earth, pursuant to the 2019 amended and restated option agreement, TMRC formed Round Top Mountain Development LLC to hold the joint venture (JV) interests of TMRC and USA Rare Earth. TMRC will own a 20% interest in Round Top Mountain Development LLC. All other corporate activities, such as TMRC’s rare earth elements from coal initiatives, as well as its New Mexico silver exploration project, are not part of the USA Rare Earth JV and remain 100% with TMRC.
USA Rare Earth recently completed a Series C funding round of US$50 million and is now funded through the completion of the definitive feasibility study (DFS). The DFS includes the pre-feasibility study, the pilot plant, and a demonstration plant to be built at the Round Top site later this year, which will include test heap leach pads and continuous ion exchange processing. The demonstration plant will support the DFS and permitting, as well as producing representative materials for evaluation by prospective customers. The Round Top JV has received construction stormwater permits from the Texas Commission on Environmental Quality and has commenced a 20 000 t bulk sample to support the feasibility studies and the demonstration plant. USA Rare Earth will continue to explore additional financing as required with its advisors, Goldman Sachs and Bank of Montreal.
MALI Resolute Mining begins blasting at Syama Mine
A
significant milestone for the Resolute and Orica partnership has recently been achieved, with the commencement of production blasting at the Syama mine in Mali using WebGenTM, the world’s first fully wireless initiating system developed by Orica. The WebGen system completely eliminates the need for down-lines and surface connecting wires by sending firing commands through hundreds of metres of rock, air and water, in order to initiate blasts reliably and safely without re-entry into
high-risk areas. Wireless blasting supports Resolute’s strategic vision of being a successful low-cost gold producer. WebGen will drive efficiency and optimisation throughout the production cycle for the mine, including increased cave flow performance and overall ore recovery by reducing the consequences of hole dislocation or loss and redrilling required. Resolute intends to utilise WebGen across its underground production operations and sees WebGen as a critical enabler to achieving its automated mine of the future vision at Syama.
AUSTRALIA Alien Metals commences Phase 2 drilling on Hancock Licence
A
lien Metals Ltd, a minerals exploration and development company, has advised that it has commenced the second phase of drilling on the Hancock Licence, part of the Hamersley Direct Shipping Iron Ore High Grade Project in the Pilbara region of Western Australia. This follows the recently completed maiden drilling programme. The company had sufficient confidence from the first batch of drill results from Phase 1 – both analytically and geologically – to return to the field and push on with an in-fill and extension drilling programme, using the same drill rig and drill team. Further, preliminary assay results have been received now
on all samples from the Phase 1 drill programme and, once quality assurance/quality control has been completed and reviewed, the company will update the market as soon as possible. The company’s focus for Phase 2 of drilling will be to seek a potential maiden resource on the Sirius Extension Prospect, adding knowledge and potential to the Ridge E Direct Shipping Ore (DSO) anomaly already defined, and will also test some newly identified DSO targets within the main area already drilled, including ridge C. If possible, the company may also consider surface reconnaissance and mapping on some untested areas to further expand its knowledge of the project. GLOBal mining review // May/June 2021
5
WORLD NEWS Diary Dates Mines and Money Online Connect 22 – 24 June 2021 VIRTUAL EVENT https://minesandmoney.com/online MINExpo INTERNATIONAL 2021 13 – 15 September 2021 Las Vegas, USA www.minexpo.com China Coal & Mining Expo 2021 26 – 29 October 2021 Beijing, China www.chinaminingcoal.com The Digital Mine 2021 03 November 2021 VIRTUAL EVENT www.globalminingreview.com/ digitalmine2021 Iron Ore Conference 2021 08 – 10 November 2021 Perth, Australia, and Online www.ausimm.com/ conferences-and-events/iron-ore AIMEX 2021 16 – 18 November 2021 Sydney, Australia www.aimex.com.au Mining Indonesia 2021 17 – 20 November 2021 Jakarta, Indonesia www.mining-indonesia.com
To stay informed about the status of industry events and any potential cancellations of events due to COVID-19, visit Global Mining Review’s events page: www.globalminingreview.com/events
6
May/June 2021 // global mining review
DEMOCRATIC REPUBLIC OF CONGO CMCO, ERG, Umicore,
and Glencore pilot cobalt traceability solution
M
ajor metals and mining companies CMOC, Eurasian Resources Group (ERG) and Glencore, in collaboration with battery material supplier Umicore, are piloting ReISource, a solution to trace responsibly produced cobalt from the mine to the electric car. A global electric vehicle pioneer and one of the world’s leading battery makers are also partaking. Tested in real operating conditions, from upstream cobalt production facilities in the Democratic Republic of the Congo to downstream electric vehicle production sites, the pilot will run until the end of 2021, with the roll-out of the final solution expected in 2022.
CANADA VivoPower International proposes US$120 million
Canadian distribution agreement
V
ivoPower International PLC has announced that the company and its wholly-owned subsidiary, Tembo e-LV B.V., have entered into a non-binding heads of terms with Canadian industrial equipment distributor, Acces Industriel Mining Inc., for Acces to distribute Tembo electric light vehicles (e-LVs) in Canada. Under the proposed agreement, Acces would commit to purchasing 1675 Tembo e-LV conversion kits through December 2026. Based upon the company’s estimates, these orders could be worth an estimated US$120 million in total value over the life of the proposed agreement, with a delivery schedule weighted towards the latter part of the proposed agreement period. The proposed agreement must be finalised prior to 30 June 2021, unless the parties agree to an extension, and all purchase commitments would be subject to the terms and conditions set forth in the final agreement. The Tembo kits transform diesel-powered Toyota Land Cruiser and Hilux vehicles into ruggedised e-LVs for use in mining and other hard-to-decarbonise sectors, including construction and defence. Alongside solar generation, battery storage, and on-site power distribution, Tembo e-LV products are a key component of VivoPower’s turnkey net-zero solutions for corporate decarbonisation. The proposed agreement follows January’s distribution agreement with GB Auto Group Pty Ltd and GB Electric Vehicles Pty Ltd. Discussions with other distributors are also active and ongoing across Europe, Africa, the Middle East, the Americas, and Asia. VivoPower is targeting the completion of its global Tembo distribution network by December 2021. VivoPower selected Acces as the company’s distribution partner in Canada because of its established, long-term experience supplying, ruggedising and servicing Toyota Land Cruisers, as well as its extensive active relationships with dozens of mining companies. Under the proposed agreement, it is intended that Acces would commit to purchase the 1675 kits from VivoPower as scheduled over the duration of the agreement; acquire an equal number of Land Cruisers or Hilux from Toyota; convert the vehicles to ruggedised e-LVs using the Tembo solutions; sell the units on; and be retained by customers for servicing and maintenance. VivoPower and Acces intend to finalise the proposed agreement as soon as practical.
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WORLD NEWS AUSTRALIA Roy Hill expands K2fly agreement
F
ollowing the completion of the SATEVA Acquisition by K2fly Ltd on 28 October 2020, K2fly has announced the first contract of the full Mining Technical Assurance suite, a 5-year contract with a total contract value of AUS$2.44 million to Roy Hill. Roy Hill is a world-class iron ore operation and the largest single iron ore mine in Australia, situated 344 km south-east of Port Hedland in Western Australia’s mineral rich Pilbara region. It is an independent iron ore operation with local majority ownership, chaired by Gina Rinehart. The operation ships more than 60 million tpy of iron ore, with approval to move up to 70 million tpy. Among the many benefits of the adoption of this suite of products is an improvement in critical mine geology through automation, resulting in improved short-term scheduling and excavation of
the ore body. In large scale opencast mines, such as Roy Hill, small improvements in grade recovery or excavation efficiency deliver significant additional value to the operator. The contract marks two significant milestones for K2fly: it is the first contract of the full suite of SATEVA products, including model management, automated-ore-blocking, and mine-geology-data-management devices that work together to deliver enhanced assurance and improved recoveries for large opencast mines. In addition, it is a significant expansion in the company’s relationship with Roy Hill, which has actively collaborated with SATEVA previously and K2fly since its acquisition of this solution. The entities will continue to expand their partnership and collaboration into the future.
CANADA Weir Minerals announces order with IAMGOLD
W
eir Minerals has announced another major order of Enduron® high pressure grinding rolls (HPGR) in gold application with IAMGOLD. An Enduron HPGR, with rolls measuring 2.4 m x 2.4 m (length:diameter), will be installed at IAMGOLD’s Côté Gold Project, Ontario, Canada. This will be the largest HPGR in Canada and the
largest in the world in a gold hard rock application. Weir Minerals’ Enduron HPGR unique design is well suited to IAMGOLD’s Côté Gold operations and will help to achieve industry-leading particle size reduction, with the lowest total operating costs. The Weir Minerals Canada team and purpose-built facilities will be providing full HPGR services for the Côté Gold operations.
SERBIA Rio Tinto partners with InoBat
R
io Tinto and InoBat have signed a memorandum of understanding to work together to accelerate the establishment of a ‘cradle to cradle’ battery manufacturing and recycling value chain in Serbia. The partnership will cover the full commodity life-cycle – from mining through to the recycling of lithium. Rio Tinto’s Jadar project in Serbia, one of the largest greenfield lithium projects in development, has the potential to produce approximately 55 000 t of battery grade lithium carbonate in Europe, one of the world’s largest growing electric vehicles markets. InoBat, a European based battery manufacturer with a battery reasearch and development facility and pilot plant being developed in Slovakia, intends to scale up its future production, through gigafactories to be built in Europe, the Middle East, and Africa. InoBat’s goal is to serve the European market with innovative energy solutions, including production and recycling of electric vehicle batteries.
8 May/June 2021
// global mining review
It is envisaged that the collaboration between Jadar and InoBat will also encourage the development of a complete European lithium and electric vehicle battery value chain that will harness and enhance local skills; environmental, social, and governance standards; and cross-border interactions for the benefit of Serbia and other European economies that wish to collaborate. In 2020, Rio Tinto approved an investment of almost US$20 million to complete the final phase of study at the Jadar project, which is expected to be finalised in 2021, with an investment decision to follow. The scale and high-grade nature of the Jadar deposit provides potential for a mine to supply lithium products into the electric vehicle value chain for decades. If approved, construction of a mine to the highest environmental standards would take up to 4 years and be a significant investment for Serbia, with direct and indirect economic benefits to the Serbian economy.
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10 MAy/June 2021 // global mining review
Andrew Britton and Timothy Perkin, Kumi Consulting, UK, explore the South American context and how evolving regulatory and market requirements for responsible sourcing will impact companies sourcing from the region.
S
outh America has historically been an important source of minerals and metals, including: iron ore, gold, zinc, silver, lead, and tin. More recently, a burgeoning demand for minerals – such as lithium, nickel, and copper – to feed the electric vehicle boom has further increased interest in the region. However, the evolving regulatory and market requirements for the responsible sourcing of these minerals brings a focus on the environmental, social, and governance risks in the region. Today, some countries’ economies are heavily dependent on exports of extractives. In 2019, over 50% of Chile’s exports were minerals or metals, primarily copper, whilst 14.5% of Peru’s, 18.9% of Guyana’s, and 23% of Bolivia’s were made up of gold. The largest country in the region, Brazil, has a more diversified economy, but still 10% of its exports are comprised of iron ore.1 This reliance on extractives is compounded by an increase in demand and subsequent production of minerals in recent years. In Bolivia, for instance, almost 360 000 t of zinc and over 64 000 t of lead were produced in 2020, an increase of over 125% and almost 500% respectively since 2005.2 Another example is the demand for lithium from countries such as Chile, which the Global Battery Alliance expects to grow by 25% each year.3
global mining review // May/June 2021
11
Although the North American and European companies and investment remain significant in the region, there has been an increase of Asian interest in the past decade. This interest has come notably from countries such as China, South Korea, Japan and India, which have all significantly increased their imports in recent years.4 For instance, China alone comprised 60% of Chilean copper exports in 2020.5 Further, China’s foreign direct investment (FDI) in the broader Latin American and Caribbean region increased from US$3.8 billion to US$109.5 billion between 2005 and 2014. By 2014, India’s FDI in the region had reached US$16 billion.4
Regulatory and market requirements For the past decade, the responsible sourcing agenda has been driven by the US Dodd-Frank Act, which requires companies to report on the inclusion of tin, tungsten, tantalum, and gold (known as 3TG) from the Democratic Republic of Congo (DRC) and adjoining countries in their supply chains. This led to the focus of due diligence efforts being made on central Africa and so-called ‘conflict minerals’. For a long time, many purchasers of minerals and metals considered that if they were not sourcing from central Africa, there was little to be concerned about from a responsible sourcing perspective. This is no longer the case as responsible sourcing expectations and regulations are now global in nature and are encompassing a much wider range of metals and minerals. Further, the uptake of these expectations is becoming a commercial imperative. For example, the London Metal Exchange’s (LME) new Responsible Sourcing requirements, (which, salient to South America, impact on the aluminium, zinc, nickel, tin, lead, and copper industries), require LME-listed brands to demonstrate that producers in their supply chain comply with strict due diligence requirements to trade on the exchange. Brands not implementing conformant due diligence practices will not be listed.6 Similarly, requirements are required of smelters or refiners that want to be listed on the London Bullion Market Association’s (LBMA) Goods Delivery List (gold or silver) or as conformant by the Responsible Minerals Initiative (3TG). Numerous other standards have also been developed, covering everything from base metals through to gemstones. At the core of global responsible sourcing expectations is OECD Due Diligence Guidance for Supply Chains of Minerals Sourced from High-Risk and Conflict-Affected Areas (the OECD Guidance). This guidance was developed to help companies at all levels of the supply chain to implement actions to strengthen responsible business conduct in mineral supply chains. Uptake of the guidance has been propelled forward by the integration of many of its expectations of the European Union’s (EU) Conflict Minerals Regulation (Regulation (EU) 2017/821). To comply with the regulation, all EU-based importers of 3TG must undertake robust due diligence on their supply chains and be able to show that the minerals they import into the EU are not contributing to issues such as conflict and human rights abuses. A key requirement of the regulation and standards that align with OECD Guidance is that companies sourcing from identified ‘conflict or high-risk areas’ (CAHRA) should
12 MAy/June 2021 // global mining review
undertake enhanced due diligence in those areas. Kumi’s CAHRA Map currently identifies eight South American countries as CAHRA.7 The likelihood is, therefore, that all LME brands and companies importing minerals to the EU that are sourcing from South America should be implementing enhanced due diligence in some or all their supply chains. Finally, proposed future EU legislation is hinting that other metals and minerals, ranging from cobalt to zinc and lithium, may also be required to meet the same expectations. In addition, the EU’s proposed Mandatory Due Diligence law would cover all supply chains for all companies with any commercial presence in the EU.
Sourcing risks in South America Indigenous rights Although in some jurisdictions indigenous peoples’ rights are protected by local law, this is not always the case. Even when there is legal protection, indigenous peoples can continue to suffer discrimination, displacement, or violence.8 When it comes to mining specifically, illegitimate land acquisition is a key risk. In March 2021, indigenous people in Northern Brazil were requesting for the Brazilian government to support them in a fight against mining speculators coming onto their land.9 For mineral companies producing responsibly, it is essential to engage with the rights of indigenous people and understand a well-established body of international law. In this instance, this includes the core right to free, prior, and informed consent (FPIC) which should be pursued when moving into areas where indigenous people may be present.
Environmental protection When poorly managed, the extractives industry can create environmental effects that impact on local communities and ecosystems. The 2019 collapse of Vale’s Brumadinho tailings dam at an iron ore mining complex in Brazil is perhaps one of the starkest examples. Another example of an environmental risk is the use of water in the production of lithium. Chile, together with Argentina and Bolivia, comprises South America’s ‘lithium triangle’. This region holds 54% of the world’s lithium resources and is pivotal for one of the key components of lithium-ion batteries, which are central to the global sustainable energy transition.10 Much of Chile’s lithium production takes places in the fragile ecosystem of the Atacama Desert and is highly water intensive as it requires brine water for extraction. This, in turn, depletes water resources and impacts on the balance of the water composition.11,12
Artisanal and small scale mining Artisanal and small scale mining (ASM) is more widespread in South America than perhaps companies sourcing from the region realise, with major private and public mining companies buying product from ASM sources. According to the ASM Inventory, the largest number of ASM operators in South America can be found in Colombia, Bolivia, and Peru.13 ASM outputs have been found to fund conflicts or exacerbate existing abuses. For example, Venezuela’s
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neighbouring countries can be transit routes for smuggled ASM gold, and paramilitary groups in Colombia have been known to profit from minerals extraction to fund their activities. There has been a tendency from mining companies to disengage from ASM production sources due to the increased likelihood of operational risks such as child labour, health and safety issues, and forced labour. However, good practice is to engage responsibly with ASM. It is only with a realistic understanding of the scope of ASM in mineral supply chains that risks can be managed.
Corruption and weak governance Companies operating in South America can often find themselves operating in areas of weak governance, increasing the risk of corruption, bribery, and fraud. This is even though governments, industry initiatives, and civil society organisations have worked to improve extractives governance and reduce corruption within the sector. This has involved establishing stricter anti-corruption laws, creating new transparency and social accountability mechanisms, and improving planning and the predictability of extractives revenue.14 However, governance and corruption risks remain, with eight countries in South America ranked as high or very high risk on Transparency International’s Corruption Perceptions Index. On-the-ground examples include low mining tax collection in Peru, consequently meaning that local communities do not benefit from the resource wealth,15 and instances of misinvoicing in Chilean exports of copper.16
How can companies address these risks and meet regulatory expectations? Due diligence is more than a tick-box exercise. Instead, it is about developing robust management systems that help companies to understand their supply chain and identify salient risks early on. This, in turn, helps companies to get ahead of developing appropriate mitigating actions. Although it is the responsibility of upstream companies to mitigate any identified risks, downstream companies are ultimately responsible for the implementation of effective supply chain due diligence. Of course, cooperation and engagement between the two should, where possible, be encouraged. An essential place to start is by getting to grips with the recommendations detailed in the OECD Guidance: Establish strong company management systems: Make commitments at policy level to responsible business conduct and include senior management in this process. Ensure staff are adequately trained in responsible business conduct. Identify and assess risks: Develop a process to identify and assess potential or actual risks in the supply chain. This article has presented four common risks in South American mining. However, companies need to understand these may not be the only ones, or indeed the highest risks, relevant to their supply chains. Respond to identified risks: Develop a risk management plan and use leverage to make effective changes.
14 MAy/June 2021 // global mining review
Verify due diligence: Have operations or supply chain due diligence independently assessed. Report annually: As a commitment to transparency, provide timely, accurate, and public reports and disclose information relating to risks, due diligence actions, and financial transactions. Further, when adapting responsible sourcing programmes to the South American context, companies may require support from local stakeholders such as civil society groups and nearby communities to understand local concerns. This should be integrated into the risk assessment process, as well as in any subsequent steps taken to address risks. Finally, although proactive responsible sourcing programmes may appear costly at first glance, they will save companies significant costs further down the line as it will reduce the impacts of severe risks and crises or being cut out of global markets altogether.
References 1. 2. 3.
4.
5. 6. 7. 8.
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10.
11.
12.
13.
14.
15.
16.
The Observatory of Economic Complexity, https://oec.world/ Instituto Nacional de Estadística, https://www.ine.gob.bo/ ‘A Vision for a Sustainable Batery Value Chain in 2030: Unlocking the Full Potential to Power Sustainable Development and Climate Change Mitigation’, World Economic Forum, (2019), http://www3.weforum.org/ docs/WEF_A_Vision_for_a_Sustainable_Battery_Value_Chain_in_2030_ Report.pdf ‘Extractives in Latin America and the Caribbean: The Basics’, Inter-American Development Bank, https://publications.iadb.org/ publications/english/document/Extractives-in-Latin-America-and-theCaribbean-The-Basics.pdf International Trade Centre, https://www.trademap.org/ ‘LME Responsible Sourcing’, The London Metal Exchange, https://www.lme.com/About/Responsibility/Responsible-sourcing ‘CAHRA Map’, Kumi Consulting Ltd, https://www.cahramap.com/ ‘Undermining Rights: Indigenous Lands and Mining in the Amazon,’ World Resources Institute, https://media.business-humanrights.org/ media/documents/Report_Indigenous_Lands_and_Mining_in_the_ Amazon_web_1.pdf ‘Brazil officials warn clash looms between Indigenous, miners’, The Associated Press, (2021), https://apnews.com/article/brazil-latinamerica-29766c5ab49251ade348efe6308c34bb ‘The white gold rush: A battle for supremacy in the lithium triangle’, The Economist, (2017), https://www.economist.com/theamericas/2017/06/15/a-battle-for-supremacy-in-the-lithium-triangle ‘Lithium firms depleting vital water supplies in Chile, analysis suggests’, Engineering and Technology, (2019), https://eandt.theiet.org/content/ articles/2019/08/lithium-firms-are-depleting-vital-water-supplies-in-chileaccording-to-et-analysis/ ‘Water rights under scrutiny in Chile’s Atacama Desert’, Mining [dot]Com, (2020), https://www.mining.com/water-rights-under-scrutiny-in-chilesatacama-desert/ ‘Global Trends in Artisanal and Smal-Scale Mining (ASM): A Review of Key Numbers and Issues’, Intergovernmental Forum on Mining, Minerals, Metals and Sustainable Development, (2017), https://www.iisd.org/ system/files/publications/igf-asm-global-trends.pdf ‘Transparent Governance in an Age of Abundance: Experiences from the Extractive Indusries in Latin America and the Caribbean’, Inter-American Development Bank, (2014), https://publications.iadb.org/ publications/english/document/Transparent-Governance-in-an-Age-ofAbundance-Experiences-from-the-Extractive-Industries-in-Latin-Americaand-the-Caribbean.pdf OLIVA, N., CONVERTI, L., OGLIETTI, G., and SERRANO, A., ‘Reparto de la renta minera en el Perú: Efectos macroeconómicos de una major distribución de la renta para el Estado', CELAG Análisis Económico, https://www.celag.org/wp-content/uploads/2019/12/mineria-peru.pdf ‘Trade Misinvoiving in Primary Commodities in Developing Countries: The cases of Chile, Côte D’Ivoire, Nigeria, South Africa and Zambia,’ United Nations Conference on Trade and Development, (2016), https://unctad.org/system/files/official-document/suc2016d2_en.pdf
Gruffudd Roberts, CRU, UK, explores the challenges copper miners must navigate to bring on new supply in order to meet the world’s increasing demand.
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rowing demand for copper – partly from the electric vehicle and renewable sectors – will lead to a significant supply gap appearing in the copper market from the mid-2020s onwards. CRU estimates that the world will need to add 5.5 million tpy of copper mine supply by the end of the decade. With copper prices at approximately US$9000/t, far exceeding the US$6000/t level which has historically supported both project approvals and merger and acquisition (M&A) deal activity, there has been a renewed spotlight on project development. It can take approximately 15 years to develop a new copper mine from exploration through to production, and this process is often beset by risks that can stall or even permanently block a project. Environmental, social, and governance (ESG) issues will be at the forefront when investment decisions are made.
Risks from political instability and social opposition in top copper mining countries Chile and Peru produced 5.7 million t and 2.1 million t of mined copper, respectively, in 2020, 38% of the global total. They are also home to 33% (on a production basis) of the world’s undeveloped projects with >100 000 tpy of copper producing capacity. However, over the past couple of years, both
countries have seen numerous scenes of civil unrest and social opposition to mining that have severely affected the industry and could reduce the viability of certain projects. Chile’s economic and political stability was challenged by the social and political upheaval that started in October 2019 and led to a referendum on constitutional reform. The vote, carried out in October 2020, was overwhelmingly in favour of rewriting the country’s constitution, a process that is expected to culminate with a referendum on the final proposal in August 2021. It is uncertain what changes a new constitution will bring to the mining industry, but water rights, regulation of mining concessions, taxation and mining royalties, as well as labour rights and environmental protection, are all areas where changes are possible. Peru’s mining industry has remained markedly resilient amidst the political instability the country has endured for years. However, the ousting of former President Martín Vizcarra, in November 2020, and the large protests that followed, have led to concerns among miners. Also of concern are the instances of social conflict between miners and communities, as has been the case repeatedly in recent years, most notably at MMG’s Las Bambas mine, which faced close to 100 days of community roadblocks and disrupted shipments last year. Protests against Southern Copper’s Tia Maria project in 2019 were also very disruptive and, as a
global mining review // May/June 2021
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result, the project will only be allowed to proceed on the condition that it wins community support, which could take years. Other major projects located in this region – such as Quellaveco, Los Chancas, and Zafranal – could also face similar opposition from communities. Other jurisdictions are arguably even more challenging for miners, such as Zambia and the Democratic Republic of the Congo (DRC). The Zambian government has changed its mining royalty and tax regime 10 times in the past two decades and has been embroiled in several disputes with mining companies, most recently with Glencore and Vedanta. Moreover, as the country’s economy has deteriorated, and its debt-to-GDP ratio has shot up towards 150% by some estimates, attempts by the state to take control of the country’s copper mines have not abated. Fiscal instability also presents significant challenges in the DRC, while resource nationalism also poses headaches for miners operating in Mongolia and Indonesia.
Environmental concerns and permitting challenges Environmental compliance is a major hurdle for copper projects across the globe and miners are facing increasing
Figure 1. Long term copper market balance depicting production required from uncommited projects to meet rising demand.
levels of scrutiny at the permitting stage. On average, greenfield projects in Chile and Peru can take up to 4 or 5 years to secure the necessary operating permits. It can take almost double that in the US, a trend that is unlikely to recede given the Biden administration’s new plans to tackle environmental issues. The Pebble project in Alaska is the most significant project to be held back on environmental grounds. Progress on the controversial project has swung back and forth over the past few years, as its proximity to a significant wild salmon fishery has led to significant opposition from environmental and community groups. While the project is now able to apply for all the necessary state and federal permits, it has recently been refused a water licence. Other projects in the country that have faced significant opposition at the permitting stage include Twin Metals in Minnesota and Rosemont in Arizona. Water use is also a contentious topic for miners, particularly in Chile, where the government has proposed that the use of desalinated water be mandatory for copper operations over a certain size. However, desalination plants come at a significant cost, both in terms of capital expenditure and operating costs, and thus have the potential to push some projects past the economic threshold. Tackling emissions is arguably the most important environmental issue facing copper miners today. CRU estimates that carbon dioxide (CO2) emissions for the copper mining industry average approximately 4.5 t of CO2/t of copper metal produced, though there is a large degree of variability on a mine-by-mine basis. Fuel consumption associated with material transport at the mining stage, in addition to electrical power use during mineral processing, are considered the most significant sources of CO2 emissions for copper. As a result, the focus of emission reduction measures has been on power generation and achieving incremental efficiency improvements at the mining and processing stages. Increasing metal recoveries, electrification and automation of mining equipment, use of trolley assist, and applying conveyor systems for material handling can help generate efficiency savings and reduce emissions overall. Miners have also been proactive on power generation, with several major producers opting for renewable power arrangements. Despite the adoption of these measures by many miners, they are by no means universally applied and will be a source of scrutiny for many copper projects in the future.
Technical challenges
Figure 2. Estimated number of years required to permit a greenfield project – politically and socially.
16 MAy/June 2021 // global mining review
Ore grades at existing operations are expected to decline gradually over the next decade. For concentrate operations, CRU expects to see a decline from 0.61% this year, down to 0.56% by 2030, while the decline will be more pronounced at existing hydrometallurgical mines. Miners in the past have compensated by increasing ore throughput to maintain production levels, which incurs higher capital and operating costs. Impurities in copper concentrates are another technical challenge that miners must navigate.
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As cleaner, simpler copper deposits are depleted, new sources of copper (some of them entailing metallurgically complex ores) need to be brought into production to satisfy growing demand. Arsenic is the most significant deleterious element; in addition to being highly toxic, it also reduces the conductivity of copper metal. Despite this, it is a comparatively common impurity in copper concentrates, with arsenic content varying over a wide range – from less than 100 ppm, to as high as 8 – 9%. Elevated fluorine levels at some key mines also captured the attention of the market in recent months. The presence of deleterious elements in copper concentrates increases the cost of downstream processing for smelters, which in turn passes on this cost to miners by applying penalties, thus reducing the overall value of the mine’s product. As easy to mine, near-surface copper deposits are becoming scarcer, copper mining is moving deeper underground. Where ore grades are lower, this necessitates the use of technically challenging bulk underground mining methods such as block caving. The initial capital costs for block caves are very high, typically in excess of US$5 billion. The large block caves that have commenced production
Figure 3. CO2 emissions curve for the copper mining industry.
over the past 2 years have made encouraging starts. However, with the copper market reliant on these large block cave operations to meet future demand, any shortfalls could see a tighter than expected market over the medium term.
Ignoring ESG issues could see investment dry up While CRU believes that the long-term outlook for copper is positive, prices are unlikely to remain at their current high levels beyond the short term, and higher-cost projects that have an attractive NPV at US$9000/t copper will struggle to receive a go-ahead if the copper price falls. Social, political, environmental, and technical challenges will have knock-on effects on project economics due to the costs involved with mitigating those issues. The investment community has become increasingly committed to promoting and delivering on ESG issues. Securing project financing has never been a simple task for mining companies, but the increasing focus on ESG compliance as a key criterion used to inform investment decisions has made the process more challenging. Failure to deliver on sustainability aims makes projects less attractive to investors, and the mining industry has already been impacted. This is especially true in the case of thermal coal, which has seen some miners and investors divest from the major CO2 emitter in recent years. Chinese state-owned mining companies follow a different playbook and are sometimes able to navigate or sidestep some hurdles others face. Expanding Chinese miner, Zijin, is set to almost double its mined copper output by 2022, following a spending spree that saw the company acquire majority stakes in Serbian project Timok, RTB Bor, Eritrea’s Bisha mine, and Qulong, one of China’s largest copper deposits. The company also has a 40% stake in Kamoa-Kakula, Africa’s largest copper project, in the DRC. In the post-COVID world, there will be more Chinese capital on the lookout to acquire assets from struggling or indebted rest-of-the-world companies and governments.
Conclusion
Figure 4. Existing copper mines are expected to experience further declines in ore grades.
18 MAy/June 2021 // global mining review
Despite copper being heralded as a green metal due to its role in electrification and renewable energy initiatives, ESG issues will command an ever-greater presence at all stages of the copper supply chain over the course of the next decade, and will be particularly critical for the investment community. There is sufficient supply potential to fill copper’s long-term supply gap, in the form of uncommitted mine projects. However, miners will need to navigate several challenges – political and fiscal instability, resource nationalism, community and social conflict, environmental opposition and permitting delays, as well as technical and financial risks – over the medium to long-term if they are to grow or even just maintain their current production levels.
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20 MAy/June 2021 // global mining review
Ulf Richter, ABB, Germany, outlines how gearless conveyor drives are powering the world’s largest opencast copper mine in Chile.
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earless conveyor drives (GCDs) are now the preferred solution in many mining projects, particularly those that require high drive power, helping to boost the efficiency of higher-capacity belt systems for greater ore throughput and reduced energy usage, equipment downtime, and maintenance costs. In the high-power regime, conventional conveyor drives face multiple challenges, mostly associated with the gearbox. Building a gearbox that can handle power levels above 3.5 MW is a complex process; once in operation they are maintenance intensive and their productive lifetime is relatively short. A GCD, in contrast, uses a large, low-speed synchronous electric motor driving directly onto the pulley shaft designed to handle the high torque produced by such motors. The motor is controlled by a variable-speed drive to produce a shaft rotational speed typically in the range of 50 – 70 rpm. There are usually several drive modules in a drive station and there can be multiple drive stations on the conveyor. Existing GCDs vary from 2.5 – 7 MW, with a total connected power of 5 – 20 MW. GCDs are also robust, require minimal maintenance, and can boost the energy efficiency of high-power systems by 3 – 8%.
GCDs developed by ABB offer mining operators these benefits and are currently being implemented at one of the most challenging mining projects of all time: the Chuquicamata mine in Chile.
Resetting the parameters for power and control In September 2020, 2850 m above sea level in the high desert of the Antofagasta region in northern Chile, the world’s most powerful belt conveyor system, 13 km long, was brought online, connecting underground operations at the Codelco-owned opencast copper mine directly to the concentrator. Two 20 MW TAKRAF conveyors each lift 11 000 tph of ore more than 600 m to reach the surface of the underground mine. The total lift is approximately 1.3 km and then the ore is fed to a 15 MW overland conveyor. GCDs were the only economically feasible way to provide enough power to run the 20 MW conveyors. The limit for an input pinion gearbox on a conveyor is 3 – 4 MW, so the belt system at Chuquicamata would have either required eight motors driving into a gearbox with an output shaft, or multiple conveyors with lower power ratings and multiple
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transfer stations. Either scenario would require substantially more materials, space, and infrastructure to deliver the requisite power. GCDs were therefore the simplest way to achieve the production output that the customer wanted, with the added benefit of reduced maintenance and significant efficiency gains. ABB, in partnership with TAKRAF, successfully commissioned the most powerful GCD system in the world, comprising a total of 11 drives with synchronous motors running at low speeds of 50 – 60 rpm, and with a rated power of 5 MW each, resulting in a motor shaft torque of roughly 900 000 Nm. The total installed drive power for the entire system, including multiple feeder conveyors, is 58 MW.
Volume control: reducing carbon dioxide and noise emissions At Chuquicamata, switching from opencast with truck/shovel operations to underground operations, using the TAKRAF
conveyor with ABB gearless drives, will help mine owner Codelco save roughly 130 million l/y of gasoline by eliminating the need for 120 large-haul trucks, bringing the mine's carbon dioxide emissions down from 340 000 tpy to 100 000 tpy – a saving of approximately 66%. In Europe, meanwhile, ABB is partnering with a mine in the Czech Republic to reduce emissions of a different kind. By upgrading shaft mounted geared drives on an existing conveyor system with GCDs, powered by synchronous permanent magnet motors, the mine owner is able to meet stringent EU noise emission limits, as well as prevent frequent motor bearing failures due to vibration issues. Drives containing gearboxes with multiple moving parts, turning at 1000 rpm or higher, can be very loud, and thus run the risk of exceeding the EU noise emissions limit of 85 dB(A) (A-weighted decibels). Using GCDs at approximately 50 rpm, ABB restricts noise emissions from the drive unit to less than 75 dBA, providing the mine with all the benefits of gearless drives, while negating the need for noise encapsulation (housing around the whole geared drive unit) or noise protection walls along the conveyor system.
Energy efficiency and monitoring
Figure 1. The Chuquicamata mine in the high desert of Northern Chile.
Figure 2. ABB's GCDs are the power behind the worlds largest opencast copper mine.
Figure 3. ABB GCDs are robust, require minimal maintenance, and can boost the energy efficiency of high-power systems by 2 – 3%.
22 MAy/June 2021 // global mining review
Unlike conventional drive pulleys with gears and motors, the 5 MW motors at Chuquicamata are directly coupled to the drive pulley and employed in the conveyor systems with four 5 MW motors, a total of 20 MW. The GCD solution is highly integrated as part of the drive pulley. A single bearing solution for the motor with a special membrane coupling was designed and patented by TAKRAF. ABB’s Mining Conveyor Control Program is a software package developed by ABB for conveyor drives control. It has been designed to run directly on the control board of its medium voltage (MV) or low voltage (LV) variable-speed drives. The software is specifically configured for conveyor applications, allowing for the setting, by parameter, of the essential conveyor drives' control functions. Used at Chuquicamata, it ensures smooth belt operation and safe synchronisation between high-power motors and high-power hydraulic brakes, necessary for secure operation of steep uphill conveyors – the GCD technology meets the high demands of the massive conveyor system for accurate starting with no roll-back and precise load-sharing control. ABB liquid-cooled MV voltage-source frequency converters, together with the large synchronous motors, deliver a decrease in active and reactive power consumption for high energy efficiency. A system that transports cooling liquid several kilometres out of the tunnel was installed to manage significant heat losses from the motors – in excess of 1 MW – in the subterranean environment. The ABB/TAKRAF solution at Chuquicamata is connected to the ABB AbilityTM System 800xA distributed control system for efficient data acquisition, equipment assessment and process optimisation, including condition monitoring of the pulley bearings. System 800xA monitors and collects data from multiple sensors embedded in the motor drive system, monitoring for failures and identifying maintenance needs.
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Overcoming logistical challenges at Chuquicamata The Chuquicamata project also constituted a major logistical undertaking. With 50% of the conveyor system located underground, installing large equipment – such as five containerised e-rooms housing the drive station and electrification, control, and instrumentation equipment – was a major challenge, particularly in the remote, dry, and dusty conditions that typify the high desert in northern Chile. ABB synchronous motors are factory assembled and tested as complete units, including the base frame, before being shipped and installed in one piece. A novel embedding concept jointly developed by TAKRAF and ABB enabled the GCD motors to be installed and aligned in a single day, a major benefit compared with existing cantilevered GCD solutions that can take 2 days or more to install. The motors can also be mechanically disconnected from the drive pulley quickly, so that operations can continue if drive failure occurs. The motor air gap is fully under control and can be re-adjusted easily. In total, commissioning of the drives at the Chuquicamata mine took just 14 days, a new record. The underground project is expected to extend operations at Chuquicamata for the next 40 years. In addition, ABB provided an installation supervisor and 100% perfect documentation of the whole drive system so that a third-party company could install it without support, as per customer requirements.
Breathe easy with ventilation on demand ABB has also installed its ventilation on demand (VoD) solution, ABB Ability Ventilation Optimizer, at Chuquicamata to provide clean air to workers in line with the strict health, safety, and environmental requirements. Ventilation systems can account for 50% of energy use in underground mines, yet production may only be concentrated in 20% of a facility at any one time. By distributing clean air only where and when people or machines are working, Ventilation Optimizer streamlines ventilation systems and
reduces energy costs, while at the same time ensuring a safe working environment for personnel. It does this by employing sensors throughout the mine that transmit real-time information regarding air quality, diesel vehicle usage, and personnel to an ABB Ability System 800xA operator for analysis. The Ventilation Optimizer then operates equipment according to actual ventilation demands – which are dynamically calculated from mine production schedules and events, as well as event equipment status and location. The VoD solution has three implementation levels, the most advanced of which uses an algorithm, sensor feedback, and advanced multivariable control technology to run all ventilation fans in optimal mode, distributing the air supply more efficiently and minimising energy consumption in real time. By controlling mine ventilation in this manner, annual energy savings of up to 50% are possible. ABB sees Ventilation Optimizer as part of the transition on the journey towards the all-electric mines of the future, by helping to reduce nitrous oxide emissions from diesel and diesel-electric hybrid trucks.
Forward thinking: future GCD and digital technologies With global demand for medium power conveyors from 3 – 10 MW for use in major projects, such as Chuquicamata, set to increase, ABB has developed gearless conveyor drives for medium power to ensure mining customers continue to reduce their cost per tonne of production and stay competitive. Meanwhile, innovations in the sphere of augmented reality now allow ABB experts to see the same view as an on-site service engineer in real time, allowing them to provide remote support, which is of value in the wake of COVID-19 travel restrictions. ABB’s augmented reality collaboration application, ABB Ability Remote Insights, digitalises the field operator experience and vastly improves interaction between field and control room operations. Operatives will be able to access hands-free, real-time data related to plant assets, processes, or procedures using industrial tablets, smartphones and Microsoft HoloLens glasses, not only increasing real-time collaboration, but also enabling immediate data entry from the user interface in the field. Similarly, ABB’s newer solutions use advanced data analytics, artificial intelligence (AI) tools, and machine learning to correlate and analyse signals from critical mining machinery, such as GCDs and motors. Not only does this equate to better online support from off-site experts, it has the potential to remove personnel from risky environments – all while maintaining mine production and maximising profits.
Conclusion
Figure 4. High drive power helps to boost the efficiency of higher-capacity belt systems for greater ore throughput and reduced energy usage, equipment downtime, and maintenance costs.
24 MAy/June 2021 // global mining review
As at Chuquicamata, GCDs can be deployed in complex, world-class projects. They can provide multiple benefits for mine operators by helping to increase efficiency and reduce energy usage, equipment downtime, maintenance costs, and noise. Together with the advent of augmented reality collaboration applications, advanced data analytics, AI tools and machine learning, mining companies and their technology partners are set to further increase the efficiency of operations, however remote or challenging.
Neil Gordon, AirEng | The New York Blower Company, shares the benefits of remote condition monitoring and predictive maintenance for mine ventilation equipment.
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eliable, energy-efficient mine ventilation equipment is critical to maintaining safe, efficient, and cost-effective mining operations. After the capital expense of purchasing ventilation equipment, energy and maintenance are the two biggest operating expenses throughout the lifecycle of a fan. However, even the best-designed ventilation systems will wear down over time and must be properly maintained, in order to ensure an energy-efficient operation and avoid unplanned downtime. Especially in harsh industrial environments – such as underground mines – fans and blowers are exposed to heavy, uneven dust loads, excess moisture in the airstream, and other adverse conditions that can reduce fan performance, cause declines in efficiency, and damage equipment if left unaddressed for too long. In addition, using more ventilation than needed increases power consumption and unnecessarily accelerates fan wear.
The benefits of remote condition monitoring Remote condition monitoring and predictive maintenance capabilities can significantly reduce power and maintenance costs by giving users greater visibility into the performance of their equipment and help them to make real-time, data-driven decisions. For example, remote condition monitoring gives users actionable data to quickly identify potential maintenance problems before they escalate to irreversible damage or unplanned downtime, as well as optimise power consumption and maintenance schedules based on
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concrete data. Remote monitoring is a minimal additional upfront cost during initial fan deployment that reduces the total cost of ownership (TCO) over the lifetime of the equipment. Over the past decade, as the Industrial Internet of Things (IIoT) has accelerated globally, remote condition monitoring has quickly become a popular solution to
effectively manage and maintain mine ventilation equipment. Two of the most common types of remote condition monitoring include: Vibration and temperature monitoring. Pressure and flow monitoring. The following are a few practical examples of how remote condition monitoring is being used in mine ventilation equipment and the value it can deliver for mining operations.
Drive reliability and reduce maintenance costs
Figure 1. Full turnkey project for Newmont Tanami VR6 main ventilation fans with the installation of multiple monitoring systems.
Maintenance is most costly when it is unexpected. For a major mining operation, a sudden, unplanned breakdown of the equipment can cost over US$1 million/hr in lost productivity if work must come to a halt while the problem is attempted to be identified and fixed. Remote vibration and temperature monitoring not only helps prevent this worst-case scenario, but also reduces overall maintenance requirements under normal operating conditions.
Vibration and temperature monitoring
Figure 2. Newmont Tanami VR6 fan motor vibration sensors measure RMS vibration velocity and monitor temperature and vibration levels.
All industrial fans have a baseline level of vibration and temperature at which they normally run-up, run-down, and operate. These baselines vary by industry and are defined by ISO. The mining industry, in particular, requires relatively low setpoints for vibration. While some fluctuation in vibration and temperature is normal and isolated spikes may not be cause for concern, sustained changes to the baseline are often the first indication of a potential problem. For example, excess moisture and heavy, uneven dust loads on the fan impeller will gradually increase vibration, reducing efficiency and eventually leading to premature fan wear or unexpected failure. Remote monitoring proactively identifies the upward trend in vibration so that it can be investigated and resolved before major damage can occur. In order to do this, vibration and temperature sensors are installed at the fan shaft and bearings to monitor for changes, and alarm thresholds are set to trigger alerts (for example, a text message to an operator’s phone) if the temperature or vibration levels exceed the defined thresholds. Personnel can then follow up on the alert to quickly diagnose and resolve the issue before it escalates into a bigger problem. This is one example of predictive maintenance.
Remote monitoring enables predictive maintenance and overall equipment effectiveness
Figure 3. Newmont Tanami VR6 shaft collar pressure and air temperature monitors transmit real-time data with an automatic calibration.
26 MAy/June 2021 // global mining review
While preventative maintenance plans rely on regular, scheduled maintenance, predictive maintenance uses real-time data from the equipment itself to reliably predict and prevent major problems that can lead to costly unplanned downtime. Predictive maintenance also eliminates human error in capturing or interpreting the data, in order to reduce the risk of expensive mistakes.
Beyond providing real-time visibility and enabling immediate intervention, remote monitoring also allows users to track trends over time, in order to continuously improve the efficiency of their operations. For example, with data captured via remote sensors, users can measure and improve overall equipment effectiveness, which is the calculation of total availability, performance, and production quality. Overall, remote condition monitoring and predictive maintenance enables users to be proactive rather than reactive. This ultimately reduces overall maintenance requirements and can help users achieve 98% equipment reliability, with shutdowns only ocurring in instances of planned maintenance.
Optimise power consumption Power is a major cost associated with mine ventilation. While the capital investment of the equipment accounts for approximately 8% of the total cost of ownership – and maintenance accounts for approximately 6% – the remaining cost is power. As such, optimising power usage and ensuring fans are running as efficiently as possible has the biggest impact to the bottom line.
Airflow and pressure monitoring Like remote vibration and temperature monitoring, airflow and pressure monitoring give operators more visibility into the fan’s performance in real-time so that proactive adjustments that save significant costs over
time can be made. With real-time airflow and pressure data, users can rapidly identify when a fan is running inefficiently and drawing more power than necessary. For example, if pressure exceeds a set threshold, the change triggers an alert to personnel to investigate why the fan is running inefficiently, so they can resolve the problem causing the excessive power consumption.
Remote monitoring enables ventilation on demand Another growing trend in the mining industry is using remote environmental monitoring to enable ventilation on demand (VoD). By using only as much ventilation as is actually needed, VoD allows users to precisely control ventilation to ensure safety for mine workers while maximising energy efficiency. In total, intelligently optimising the ventilation can reduce power consumption by up to 50%, savings that add up over the lifetime of the fan.
Conclusion Incorporating remote monitoring and predictive maintenance capabilities into mine ventilation equipment upfront improves the reliability and efficiency of an operators' solutions, significantly reducing the total cost of ownership. Partnering with a knowledgeable and experienced ventilation equipment manufacturer can help operators customise a reliable, cost-effective solution for applications.
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28 MAy/June 2021 // global mining review
Pierre-Marie Maurice, David Kupiec, and Aimilia Neroutsou, Total, France, review a recent innovation in hydraulic fluids that is set to provide greater safety to the mining industry without compromising performance.
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lmost half of all fire incidents in underground mines are caused by hydraulic fluid leakages, making the use of hydraulic mineral lubricants in the underground mining industry a sensitive topic which needs to be addressed, requiring attention and immediate resolution. Underground fires due to hydraulic leakages have been examined by the relevant regulatory bodies, and governments are subsequently seeking to regulate the mining operators to seek a safer resolution. Up until now, mining operators have faced the difficult challenge of finding a suitable product in the market to fulfill operational requirements. Total is now ready to present its own solution to meet this demand, by offering an innovative technology to Tier 1 mining clients, ensuring a Total core value of keeping safety at the heart of its business, across all sectors, including mining.
Fire-resistant hydraulic fluid Fire-resistant hydraulic fluids have been developed to replace petroleum-based fluids in applications where there is a higher potential ignition source. The types of fire-resistant hydraulic fluids are categorised and defined within the ISO 6743-4:2015 standard. Those with fire-resistant properties within this standard are divided into six categories: HFAE, HFAS, HFB, HFC, HFDR, and HFDU – referring to the types of formulations. For mobile equipment, HFDU is the only non-water based and is the most common fire-resistant hydraulic fluid used in the mining industry technology (except for HFDR, which is only used in very specific cases), but it has its limitations. This type of fluid is very often based on synthetic esters derived from vegetable oils and has relatively similar mechanical performances compared to mineral oils. However, it is still flammable and the stability of the ester in water can be questionable.
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The less flammable technologies are water-based – HFA, HFB, and HFC – but these fluid types typical lack lubricity, and so tend to be found on static equipment with less demanding requirements and derated pumps.
Figure 1. Hydraulic fluids categories ranking.
Following the market demands for a water-based technology with superior mechanical performances, comparable to mineral or HFDU fluids, Total has introduced an innovative technology. It combines the fire-resistance performance of water with the equipment protection properties and environmental responsibility that conforms to the highest standards. The HFC-E concept has been launched to make a breakthrough among the existing fire-resistant technologies in the market. Dedicated to delivering the uppermost mechanical performance, and boosted with anti-wear and other relevant additives, the fluid aims to provide optimal equipment assurance and protection.
Fire-resistant properties
Figure 2. Fire resistance characteristics.
In general, water-glycols mixtures, water-in-oil emulsions, and synthetic fluids are less hazardous and more fire-resistant hydraulic fluids. Even if fire-resistant fluids have a lower fire hazard than petroleum oil, all have the propensity to ignite under extreme conditions. Although fire-resistant fluids are not fireproof, they significantly reduce the potential fire hazard associated with oil-based fluids. HFC-E surpasses the fire resistance of prevailing HFDU fluids used in the market. Its RI ignitability index is ‘D’ rated, compared to the ‘G’ classification of HFDU hydraulic oils (according to ISO 15029-2:2018) – ‘A’ represents the most fire-resistant category.
HFC-E fluid performances
Figure 3. Vickers pump test results for Total HYDRANSAFE HFC-E ring and valve weight loss (mg).
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Mobile mining equipment experiences harsher constraints as it is exposed to more severe shocks and vibrations. Hence, higher-ranking mechanical performances are essential for the hydraulic fluid in use in these circumstances. The current HFC technology has been extensively examined and used as the basis of Total’s new HYDRANSAFE HFC-E, which maintains its fire-resistance characteristics as it is based on a
water-glycol formulation. Nevertheless, its classic water-glycol technology has been enhanced with carefully selected molecules, in order to improve its anti-wear and anti-corrosion performance. This aims to boost equipment’s resistance to the harsh operating conditions that are often associated with work in the mining industry.
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Pump protection Total has achieved another milestone with the launch of HYDRANSAFE HFC-E, as reflected by a world-renowned original equipment manufacturer (OEM) of pumps issuing a letter of reference, indicating the product’s utilisation in bent axis pumps and motors, without limitations. In addition to the previously-mentioned attributes, HYDRANSAFE HFC-E provides better cooling to hydraulic circuits than a mineral oil. Indeed, laboratory test results showed an improvement of approximately 12% in the cooling capacity of a hydraulic system using this new fluid type, under specific conditions, compared to a mineral oil. This overall lowering of the system temperature leads to improved equipment reliability and potential energy efficiency.
Field experience HYDRANSAFE HFC-E has not only demonstrated impressive results in lab scale testing, but also proven its capability in the field, delivering operational performance whilst ensuring fire risk reduction. Thus, RAG, one of the largest mine owners and operators in Germany, has benefitted in reducing operational costs by replacing all HFDU and mineral hydraulic products with HYDRANSAFE HFC-E, attaining an effective total cost of ownership approach. Similarly, one of Total’s partners in the Asia Pacific region decided to replace the HFDU hydraulic oil which it had utilised for many years with HYDRANSAFE HFC-E. Due to the nature of underground mining, water contamination of hydraulic systems is a common problem resulting in escalation of wear and fluid incompatibility. The application of HYDRANSAFE HFC-E, due to its unique water-based formulation, eliminates the effects of water contamination and associated wear. This is due to the anti-wear and other additive types acting synergistically to deliver optimum equipment protection against wear, corrosion, and other such effects.
Conclusion Selecting the right fluid is fundamental to increasing equipment reliability, especially in severe mining operations. While the mining sector is a core market for the HFC-E fluids, other sectors that operate in an underground environment, such as tunnelling, also have the potential to benefit from this new development.
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Figure 1. Technology has a critical role to play in the digitalisation of mines.
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Dr Thomas Paul, HUBER+SUHNER, and John Hooper, Ampcontrol, explain how plug and play is the future for reliable, secure mining connectivity and communications.
s mining operators augment profitability by reducing operating costs, raising asset utilisation and improving safety performance, there has never been a greater need for digitalisation within the mining sector. With mines growing deeper underground and new reserves located predominantly in remote locations, it is becoming abundantly clear that technology has a huge part to play.
With the fourth industrial revolution beckoning, increasing numbers of next-generation technologies – such as sensors, automated or self-controlled equipment, and data-heavy automation solutions – are being adopted to allow for smoother and more efficient operations. All of this, however, requires reliable, high-bandwidth connectivity to manage the large amounts of data necessary for the successful daily running of the mine.
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Delivering mission-critical communication Robust high bandwidth networks are imperative for the mission-critical communications that take place within mines, both above and below ground. Data links are the backbone of automated operations and safety critical infrastructure – transmitting information from sensors, CCTV, and voice communications throughout the mine. In order to fulfil their role, data streams need to pass over long distances and through challenging environments. Next to the quasi-unlimited data bandwidth, fibre optic links are also intrinsically immune to electromagnetic fields, provide galvanic insulation and remain future-proof, while permitting for bandwidth-extension as demand grows. But the harsh environments of a mine can also pose a risk for the physical integrity of such networks. With mining operations heavily reliant on their communications infrastructure to keep operations running, the invulnerability of the link to and between personnel and machines underground is crucial. Any outages or failures can result in downtime, the costs of which scale rapidly with duration. In order to avoid this, it is vital that companies adopt high-performance, high-quality, and long-life solutions that enable seamless underground connectivity.
Quick and easy-to-deploy infrastructure is key In mining, production depends entirely upon having a network which is continuously accessible, in order to enable reliable communication between sensors, workers, and machines. With so much relying on it, it is evident that any damage to a mine’s fibre optic network can cause significant expense and safety hazards. Network failure and outages prove a major headache for operators, with personnel having to be removed and work stopped in affected areas underground. Therefore, it is essential there is a quick fix for when things go wrong and damage occurs. The ability to repair a network quickly is a serious challenge faced by companies throughout the industry,
with issues underground being time consuming to solve. Finding an available qualified fibre optic engineer certified to work underground at short notice is challenging and costs for such experts are high. Whilst damage to fibre optic networks cannot be completely prevented, there is an answer for operators looking to reduce downtime on the network and get back to normal much quicker in the event of a network malfunction. The trick is to use quick and easy-to-deploy infrastructure that enables fast, rapid repair – even by staff who are unskilled in fibre optic engineering.
Utilise plug and play technology HUBER+SUHNER and Ampcontrol have combined their respective knowledge to create a speedy, innovative solution called H3RO – a robust toolkit for fibre optic networks designed for the harsh conditions in underground mines. Rapidly installed and maintained, it enables mines to deploy and expand their networks conveniently and hassle-free. Moreover, it allows them to get back to normal quickly and efficiently when things go wrong. H3RO comprises a set of a pre-terminated modular fibre optic cable assemblies and fibre optic breakout terminals (distribution units), which removes the need for specially trained engineers for installation. Its plug and play elements support standardisation across mines of all sizes and regions. This has allowed for reductions in cost, easier rollout, consolidation of spares, and consistency for high-quality expansion within tough environmental conditions. Combining telco grade low-loss high density push-pull and screw-on connectors with fit-for-purpose industrial breakout terminals (BOTs), cable armour and glands, forms a reliable and robust industrial solution. The BOTs remove the necessity of having large enclosures and minimises common failure points, such as unnecessary patching and needless connector exposure. This single-mode fibre optic system supports both Passive Optical Network (PON) models and traditional Ethernet, replacing the need for time consuming fibre optic terminations in the field with a standardised future-proof infrastructure. With communication networks being critical to the core of operations, it is essential that mine operators have access to quick and easy solutions for when failures occur or when network expansion is required.
Bringing the concept to reality
Figure 2. Environments can get exceedingly challenging in underground operations – for personnel, as well as for equipment.
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In most cases, when a mine’s network is damaged, work ceases due to the loss of essential safety communication between those working on the surface and those underground, along with the ability to continue operating autonomous machinery or other digitalised features. However, when a copper and gold mine in Western New South Wales, Australia, experienced an outage caused by the severing of a communications cable, downtime was limited to the shortest time possible by adopting the H3RO solution to ensure a quick and simple repair.
As a result of H3RO’s ease of use, workers unskilled in fibre optics were able to safely deploy the solution and enact a fix to get the mine’s operations back up and running. The IP68 connectors and bulkheads allowed for the system to be seamlessly integrated within the existing infrastructure. The hassle-free, simple repair instilled confidence for future fast recovery in similar incidents or potential network expansion. When installing new or replacement infrastructure, it is quite common for parts to be modified in the field to fit with the existing setup. This can be problematic within the harsh environments of mines, which can see fibres being exposed to dust, mud, and other potentially damaging elements. However, since H3RO’s modularity covers a breadth of application embodiments, additional modifications were not necessary. The mine workers simply swapped out the damaged section for the newer one, meaning time-consuming fibre field splicing was not required. Another deployment saw the same solution providing network connectivity to underground mining equipment within a coal site, where autonomous operations were carried out with machinery. The fibre optic backbone required throughout the mine needed to offer easy integration with new and existing equipment, including third-party panels and components. Due to the functionality of the system, monitoring and control of underground equipment was achieved by utilising pre-existing FOBOT panels throughout the mine, enabling rapid, uncomplicated expansion of the network by site staff, resulting in a high-quality, low-loss dynamic network. With a robust solution created specifically for use within harsh environments, mine operators can be certain that their fibre optic infrastructures not only deliver high performance, but high levels of practicality too.
Preparing for the demands of the future There are many options for mining operators to consider when selecting fibre optic infrastructure for their communication networks and connectivity. A report by the World Economic Forum and Accenture forecasts that by 2025, digitalisation will have added more than US$425 billion of value to the mining industry, with around 1000 lives saved and 44 000 injuries prevented. As such, operators within the sector will rely more and more on next-generation technology, as they become increasingly squeezed for higher efficiency and profits. With so much riding on their networks, it is essential that companies take advantage of systems that are simple, risk-free, cost-effective and that will upgrade and improve performance within the mine, while offering easy adaptability and expansion options to meet future requirements.
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Thiru Veeraraghavan, A.W. Chesterton Co., USA, provides insight into how using the Internet of Things for preventative maintenance can thwart pump and valve failures in aluminium processing.
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critical aspect of mining and producing aluminium is processing bauxite. This process, which goes by the term ‘The Bayer Process,’ was invented more than 100 years ago by Austrian scientist, Karl Josef Bayer. During the procedure, aluminium hydrate is extracted from bauxite ores to produce 1 t of aluminium for every 2 – 3 t of bauxite.
Case study: North American aluminium processing plant At a global mining company's extensive aluminium processing plant in North America, over 1 million tpy of aluminium is produced using this process. Although often overlooked, this facility, like every other aluminium processing facility, counts
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on the reliability of pumps and valves, in various stages of the process, to minimise downtime and avoid catastrophic failures. For decades, this North American plant has relied on the support of the A.W. Chesterton Co.’s hydraulic sealing solutions to ensure pump and valve reliability and extend the hours of operation between maintenance intervals, in order to increase overall asset life. In addition to mechanical seals and valve packings, Chesterton provides industrial gaskets and specialty industrial lubricants, as well as advanced wear and corrosion protection composites. The company is a knowledge provider with strong technical support and hands-on local service.
Figure 1. Chesterton Connect Internet of Things (IoT) hardware in use on a pump.
Pump vibration challenge leads to initial Internet of Things sensor implementation In early 2020, the plant’s operators approached Chesterton regarding a vibration problem with a pump that plays a significant role within the aluminium production process. They noticed that the hydrate pump – one of the most critical pumps in the entire plant – would infrequently but aggressively vibrate when it was turned on and ramped up to 1200 rpm. Given the erratic vibrations would occur for only 5 – 10 minutes during the pump's activation, the service team could not pinpoint the root cause of the problem. By the time servicing crews arrived with a point-in-time vibration monitoring device, it was too late to catch the vibrations. Nevertheless, the issue still needed to be addressed, as vibration can signal imbalance, misalignment, looseness, and late-stage bearing wear – all early warning signs of impending failure. Without addressing the fault, plant operators would risk needing to replace a US$40 000 pump. To solve the problem, Chesterton suggested installing Chesterton Connect, a simple, Bluetooth-enabled Internet of Things (IoT) solution, developed in collaboration with Preddio Technologies, for 24/7 condition monitoring to pinpoint the time and area where the vibration was occurring. The plant operators agreed to adopt the approach and quickly set up a single Chesterton Connect sensor on the pump. Diagnostic vibration information from the pump was relayed to maintenance, which allowed the customer to spot the issues that were causing the vibrations. When the pump was started, the vibration insights extracted from the sensor spotlighted a clogged impeller as the root of the problem – product had settled down inside the pump housing, causing increased vibration. As a result of the findings, maintenance workers now know when the pump is shut down for more than 24 hours, it needs to be cleaned out before starting up again. These changes mean they can avoid doing damage to a critical piece of equipment. More importantly, from a business continuity perspective, they eliminated potential downtime and production waste, which could have run up to US$100 000/hr. In addition to detecting irregularities in equipment performance, Chesterton Connect was also able to identify instances when the pump and valve equipment used was not the right equipment for the job. On one occasion, after further analysis of a similar pump valve using data extracted from the sensor, maintenance workers found that the pump valve used was the incorrect size – they would need a completely different type of pump valve. These insights allowed the plant's team to take action and make slight changes to their operations, without needing to replace the US$40 000 pump fully.
Plant-wide deployment of IoT for preventative maintenance
Figure 2. Illustration of Chesterton Connect being used on a pump to detect surface vibration, temperature, and process pressure.
38 MAy/June 2021 // global mining review
The ability to easily install Chesterton Connect and identify the cause of the vibration problem on the hydrate pump (and similar pumps) highlighted the potential to facility operators for using the solution across the plant for preventative maintenance. Rather than relying on a set schedule to service a piece of equipment every month or quarter to prevent future failures, the sensor provided condition monitoring that could better dictate the need for maintenance in real-time.
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In that sense, Chesterton Connect makes preventative maintenance a responsive process. Furthermore, unlike other IoT solutions that the plant had tried and failed to implement in the past, it was installed for a fraction of the cost of other solutions. Before using the sensor, the plant had tried standalone vibration sensors connected to a newly installed WiFi roof antenna. However, this solution proved costly and the plant saw its spending reach into the six-figure range. Additionally, the software was not user-friendly, and the sensor proved to be unreliable. Maintenance staff found that the physical sensor was frequently knocked off of equipment by routine machine movement or inadvertent worker contact. What started as a finite issue – installing a Chesterton Connect sensor to monitor a single pump – has resulted in over 50 Chesterton Connect devices being deployed within the facility. Furthermore, the global mining company has also deployed the solution within its other plants. The ease of deployment has been a significant reason why the install base has expanded so quickly. Plant staff can now quickly move between various equipment when new use cases arrive. In addition, as the use of the sensors scaled throughout the facility, the plant service team worked with Chesterton to install an even more user-friendly IoT gateway, so that service workers no longer need to walk to all 50 sensors. Chesterton Connect devices still use Bluetooth connectivity, but the sensors communicate with the gateway to send data to the cloud. Now, maintenance workers can utilise the gateway to enable remote monitoring from nearly any device and at any location, via a cloud dashboard. Both plant service managers and Chesterton executives now monitor equipment throughout the plant, analysing vibrations, surface temperatures, process temperatures, and process pressure. As such, teamwork between the global mining company’s plants and Chesterton continues to produce further savings, since condition monitoring ensures that maintenance tasks are performed when warranted, rather than with a rote or time-based plan. For example, before establishing Chesterton Connect within another one of the company’s plants, maintenance workers were having an issue determining the pressure within a particular stuffing box. Although there are a handful of calculations one can use to determine the stuffing box pressure, the results are never the exact amount – rather a ballpark estimate. After collaborating with the plant and the outside engineering team that built the facility, the teams figured if the flush water pump could correctly pressurise the
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seal to prevent product backup, they could gain more visibility into the stuffing box's pressure by installing the sensor within the pump itself. The process was straightforward, with an adapter set-up behind the seal and a port and sensor attached inside the device. After even just one 20-minute cycle with Chesterton Connect collecting data in the background, the plant can now obtain a more accurate pressure percentage inside the stuffing box. With 50+ IoT sensors installed within its plants, the global mining company expects to increase the use of Chesterton Connect across its mining operations. IoT applications have common themes across industries, regardless of the segment. Predictive analysis, improved efficiency, increased safety, and optimised productivity strategies can be used separately or in tandem, in order to drive deployment in most commercial or industrial applications. As such, the Chesterton Connect IoT solution can be utilised across all types of mining and refining processes to detect and monitor any pressure, such: as air, liquid, and gas. The global mining company’s maintenance workers in this case benefitted from having a monitoring solution that continuously analyses air pressure. Physical asset performance analysis, including condition monitoring and failure prediction, are the keys to improved outcomes. Today’s industry primarily operates on a simple model: if the asset is broken, then fix it; otherwise, check on it periodically. This traditional practice is inefficient. Alternatively, using IoT to predict failures before they occur, while learning what is needed to prevent a repeat failure, has proven to be a better approach. A single equipment failure can often pay for the IoT system many times over.
Conclusion Improving overall equipment effectiveness is also essential to take into consideration. By leveraging the power of cloud computing and IoT, it is possible to deliver exceptional returns. Industry 4.0, powered by IoT, broadly represents many emerging methods in the mining and broader manufacturing industries, all focused on improving productivity and reliability. Productivity use cases can deliver the highest returns on investment. Transitioning mining operations into Industry 4.0 is no easy task – especially in the age of many mining facilities – but simplified and cost-effective IoT solutions are finally offering forward-thinking mining operators a bridge to the future.
Kevin Slemko, Major Drilling Group International Inc., Canada, outlines the process of supporting the delivery and ramp up of a new hydrofracking programme for Freeport Indonesia at the Deep Mill Level Zone mine.
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ocated in the highlands of New Guinea and in the Indonesian Province of Papua is Freeport Indonesia’s Deep Mill Level Zone (DMLZ) underground mine. Known as one of the world’s largest copper and gold deposits, DMLZ is found below the Deep Ore Zone (DOZ) mine where 2021 production rates are expected to average approximately 60 000 tpd of ore from several production blocks. In 2022, an increased 80 000 tpd of ore is expected.1 It is here that Major Drilling has partnered with Freeport, using specialised drilling techniques to support hydrofracking and mitigate mine-induced seismic activity in the DMLZ. Major Drilling provides block cave preconditioning services and
equipment to help mitigate the mining-induced seismic responses from mining in the DMLZ (Figure 1). As caving operations have progressed in the DMLZ, mine induced seismic responses have increased, leading to several changes, including the use of hydrofracking to help mitigate issues.
The project Undercutting began in August 2015 and progressed until the seismic response to the caving process began to increase. Those initial seismic events caused damage to tunnels at the mine, mainly around the extraction and undercut levels. Realising the
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rock mass being caved was more massive and competent than originally planned, Freeport teams determined that a hydrofracking programme to precondition the rock mass would be beneficial in mitigating the seismic response, primarily due to a series of seismic events between August 2015 and March 2019.2 In block caving, companies rely on the rock breaking along natural fractures once a certain span is achieved. When this
natural breaking did not happen as expected in the DMLZ, Freeport began seeing higher stresses in the supporting rock until the rock could not take it anymore, resulting in a sudden release of stress or mine-induced seismicity.3 Freeport teams responded with a rapid redesign of the DMLZ mining process, in order to improve the response to the actual ground conditions being encountered. Several different initiatives were applied, including pre-conditioning the rock mass using hydrofracking. Major Drilling joined the project to help support the drilling and fracking initiative.
The process/solution At the DMLZ, teams continue to use a block caving method for extraction, a mining system that involves undercutting an ore body and then allowing it to collapse under its own weight. Block caving is a cost-effective method of mining large mineral deposits. The DMLZ’s dominant rock type is diorite, a very strong and generally competent rock mass. Challenges that come with block caving can include: stalling of progressive caving, draw-point blockage, reliable prediction of orebody caveability, cave propagation, and ore flow management. One solution is hydrofracking to precondition the block cave. Block caving preconditioning benefits underground projects as it: Increases caveability. Reduces the size of rock fragments during caving. Reduces the risk of mine-induced seismic events. Figure 1. Major Drilling’s LM drill is used in underground hydrofracking and block cave work.
Working together with Major Drilling teams, Freeport Indonesia has been able to effectively reduce mine-induced seismic damage at the mine, with the help of sophisticated monitoring equipment, pumps, and packer systems.
Equipment and expertise
Figure 2. Packer system for hydrofracking used in block cave pre-conditioning detail.
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The Major Drilling team at the DMLZ is responsible for operating and maintaining the equipment associated with the specialised drilling process, along with communicating to Freeport engineers the progression of fracs, as per Freeport’s instructions. These efforts result in teams: identifying ideal fracture sizing; finding out how long fractures will take to form; discovering the necessary pressure to form a fracture; and determining water needs to produce a fracture. Drill holes made by a Major Drilling LM underground drill make way for packer installation (Figure 2). Once the packers reach the designated location, a balloon on either end of each packer inflates air up to 13 000 psi, remotely sealing in the centre of the tool. Then, pumps move high-pressure water, averaging 3000 – 7000 psi, into the drill rods and out of the centre of the tool. Once the water pressure is higher than the natural pressure of the rock, the ore body cracks, and the fracture forms. The high-pressure water interacts with the geology to break up rock and this hydrofrack reaps the desired results. Major Drilling supports and operates underground diamond drills, coupled with three complete hydrofracking setups, in the mine to drill and frack holes in accordance with project management. From among the 14 LM underground core drills Major Drilling provides at Freeport Indonesia, seven are
dedicated to supporting the hydrofracking project. Drillers also operate three hydrofracking pump systems. Two pumps were set up at the DOZ level for the sub-vertical holes, and the other was deployed on the DMLZ undercut level in the drilling of sub-horizontal holes from outside the abutment. Freeport Indonesia project managers added a fourth, spare pump in 2020. Pumps on the DOZ level focus on the area above the existing undercut. This promotes cave propagation. The main goal of preconditioning the rock mass using hydrofracking is to help reduce the seismic response around the edges of the caved area or abutment zone. The hydrofracking holes at the DMLZ are long and very challenging. Two drills are stationed with each pump – an approach designed to increase the hydrofracking efficiency (Figure 3). Teams perform fracking procedures in a controlled environment. They clear, barricade, and monitor all pressurising areas. From the secured control room, where all systems are monitored and controlled, teams receive measurements of water pressure and flow, multiple pump pressures, injection pressure, and packer pressure. Major Drilling teams use the following equipment and methods at the site: Underground core drills. Fracking pumps. Mixing tanks. Blending and gel tanks (when required). Electrical and control room. High pressure treating iron. High pressure purpose-made drill pipe. Holes are surveyed and viewed by an in-the-hole camera. Holes may be cemented and drilled out if required to have a smooth contact for the packers.
advance caving and production activities. The DMLZ mine started hydrofracking in September 2018. The project restarted undercutting in March 2019.2 By September 2019, the DMLZ mine had completed over 4500 fracks in 49 holes that supported undercutting and drawbell development, which led to an increase in production (Figure 4). The application of hydrofracking and other initiatives has resulted in an overall reduction in damage from seismicity.
Figure 3. Hydrofracking drill holes are illustrated between the DOZ and DMLZ mine levels. Source: Freeport Indonesia.
Safety is always considered first when embarking on projects, and crews are well trained in safety protocols. Major Drilling enacts safety programmes as part of every operation, including risk assessment of critical tasks as part of a safety management programme.
Results The application of hydrofracking, as well as other initiatives, allowed the DMLZ mine to
Figure 4. Fracking, production mucking, and underground core blasting from 2015 to 2019 improved production levels after the hydrofracking programme commenced in August 2019. Source: Freeport Indonesia.2
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References 1. 'Deep Mill Level Zone (DMLZ) Mine (Grasberg Complex)', Mining Data Online, (2021), miningdataonline.com/ property/3329/Deep-Mill-Level-Zone-(DMLZ)-Mine.aspx 2. NUGRAHA, N., BASTIAWARMAN, R. and EDGAR, I., 'Initial setup of hydraulic fracturing in Deep Mill Level Zone (DMLZ) underground mine, PT Freeport Indonesia, Papua, Indonesia', MASSMIN 2020 Conference and Exhibition on Mass Mining, (2020). 3. 'Hydrofracking Yielding Promising Results at PTFI’s Deep MLZ Mine' E-BeritaKita Monthly Bulletin, (30 November 2018), ebk.ptfi.co.id/highlight-news/ hydrofracking-yielding-promising-results-at-ptfi-s-deepmlz-mine 4. 'PSM Evaluation – HF and Damage Correlation Report', Figure 5. Results of seismic damage events pre and post-hydrofracking at the Freeport Indonesia Report R4-R5 Damage Occurrence, Freeport Indonesia DMLZ mine.4 (19 November 2020). 5. 'Defining Reads: Block Cave Pre-conditioning Additionally, the rate of damaging seismic events has been Yielding Promising Results in Indonesia', Major Drilling, significantly reduced since control measures including https://www.majordrilling.com/promising-results-in-indonesia
hydrofracking were implemented at the DMLZ (Figure 5). The results desired by both Major Drilling and Freeport Indonesia were realised and delivered, and the drilling teams grew their working knowledge of the systems required to safely frack and further strengthen the partnership between the companies.5
Conclusion Hydrofracking has proven an effective way to mitigate mine-induced seismic activity at the DMLZ, resulting in impactful improvements that have helped stabilise the seismic impacts through block cave preconditioning.
SEEING IS
BELIEVING
Note The Major Drilling Indonesia Branch thanks the Freeport Indonesia Engineering and Operations teams and the Geotech and Monitoring groups for guidance in ramping up drilling equipment and staff for the hydrofracking contractor partnership at DMLZ. Special thanks to Freeport Indonesia staff Nico Nugraha, Superintendent of Underground Engineering; Rifki Bastiawarman, Engineering Manager at DOZ and DMLZ Mine; and Ian Edgar, VP of Engineering, for contributing to the case study content in this article.
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Peter Malmberg, Epiroc, Sweden, explains how inventory management can increase productivity.
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roductivity, safety, and sustainability are all key factors for drillers looking to increase efficiency and profitability. The quality of the rock drilling tool is essential for getting the most out of a business. A premium quality drill bit provides more drilled metres per bit, minimises operator contact with the bit, and reduces raw material consumption in production, as well as transport. These advantages can be further enhanced through smart inventory management. By monitoring stock levels and consumption in real time, a driller has a far better view of how a certain drill rig and operator is performing. It also helps reduce inventory requirements, since the need for excess stock to buffer against uncertainty is eliminated.
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Inventory applications Swedish company, Epiroc, has developed the Smart Inventory Management (SIM) application to perform just this. The objective when developing the application was to increase efficiency related to the management of inventory located at a customer’s site. The SIM application also gives insight to consumption per
piece of equipment and/or operator, and is therefore a tool to support performance monitoring. The overall objective is to create a ‘real time total cost per measure’ reporting system. The company’s push to develop solutions in automation and digitalisation has culminated in a concept called the 6th Sense. The 6th Sense offering is a complete solution with which Epiroc provides diverse, but closely intertwined, products and technologies to simplify and streamline customer operations.
The need for a digital solution
Figure 1. The Smart Inventory Management (SIM) application provides an efficient overview of drilling tools inventory.
Figure 2. By using digitalised inventory management, the need for excess stock to buffer against uncertainty is eliminated.
Inventory management for stock located far out in the supply chain, typically in remote mining areas, is time consuming and commonly conducted with low frequency, resulting in late responses. Transactions are typically noted with pen and paper, using a template to make sure that the required information is collected. Consumption is difficult to monitor, often resulting in either too high or too low stock levels. It can also result in obsolete inventory, as supply struggles to keep up with actual swings in demand. It is clear that there is a lot to gain by having improved supply chain visibility and that the development of the SIM application is a step in the right direction towards digitalisation in rock drilling tools. At the outset of the project, three major benefits were targeted: Improved customer service by receiving timely information when goods are withdrawn – thereby suppliers can better respond to customers’ inventory needs, in terms of both quantity and location. Minimised demand uncertainty by constantly monitoring customers’ inventory and demand stream – lowering the need for large, unexpected inventory orders. Reduced inventory requirements by knowing exactly how much inventory a customer is carrying – allowing for the supplier’s own inventory requirements to be lower, since the need for excess stock to buffer against uncertainty is eliminated. Given these objectives, the need for a digital solution that would automate processes for efficient inventory management, report stock movement in real time or near real time basis, and pass information immediately to an enterprise resource planning (ERP) system for execution was identified. The ideal system would provide integrated management of primary business processes, in real time, mediated by software and technology.
Connectivity
Figure 3. The SIM application can help drillers get information regarding how a certain drill rig and operator is performing.
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The SIM application is designed to work while connected to the internet above ground, and offline while underground. This is made possible by storing data locally on a device and then uploading it once the user is re-connected. Epiroc aims for its SIM application to support all devices, having built it using progressive web applications (PWA) architecture. Today, it supports integrations with Epiroc ERP systems, but in the future it
will be possible even to connect to external ERP systems, if the customer require this support. When a user registers information in the application, the application will then send the data to an integration layer. The reason for using an integration layer is to enable other ERPs to integrate without changing anything in the application. The integration layer will then forward the data to the assigned ERP system, which will then save the data and in turn send it forward to the Global Inventory Management system (GIM), which is the system used by the supply chain for monitoring stock levels and consumption. The GIM will then analyse the consumption and suggest purchasing orders to replenish the consignment. If the device is offline, the information will be cached on a phone and automatically sent to the ERP when the device is connected If a warehouse is not replenished via a GIM, the administrator can still analyse the GIM suggestion and place orders based on the information. The ERP will then push data back to the application via the integration layer making sure that that stock levels will be always synchronised. The application provides the appointed administrator with the transaction history, specifying which items were taken, in what quantities, and to which machine and operator the items were assigned. This will enable the administrator to effectively investigate the reasons for potential discrepancies and enable a faster reaction time on swings in consumption.
The SIM application is now being rolled out to selected customers and the benefits are being shown, with reduced administration and improved quality of master data. The system installation is executed in a controlled manner, including mapping and analysis of the logistic process. Actual results vary with the complexity of the existing process, but there is typically a process improvement in place after implementation. These are all improvements that already justify the SIM application, while the true value related to data driven actions from having real time insights will take a bit more time to confirm.
Conclusion Keeping track of drilling tool inventory has long been a challenge for most companies in the industry. Relying on experience has been one way, but that comes with varying degrees of accuracy. Not knowing how the drilling operation performs means that drilling tools may be changed too early or too late, creating inefficiency in the drilling operations. In the worst case scenario, the machines stand still due to empty inventory, affecting profitability. For very remote sites it is even more critical to have an accurate inventory calculation, as the delivery times can be very long. From a sustainability standpoint, actual knowledge of how the drilling rigs and tools are performing enables more accurate predictions of how much inventory will be needed, which reduces the risk of having to place additional orders. This leads to fewer transports and a reduced environmental footprint.
Dr Dariusz Lelinski, FLSmidth, USA, outlines how new approaches to flotation and froth recovery can cut coarse particle loss and increase efficiency.
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lotation systems are a vital technology in minerals processing and extraction. But, despite their overall effectiveness, particles of valuable ore still get disposed of along with waste material. These can add up, accounting for a significant loss in potential revenue. Additionally, the energy consumption that flotation systems require to function effectively is high. So, while flotation systems are necessary when recovering ore, making them more sustainable and energy-efficient has been a challenge. One recent approach to optimising flotation has been to divide the flotation process into its two constituent stages: the first part is the formation of the bubble-particle aggregates in the slurry; and the second is the recovery of these aggregates in the froth. Historically, most attention – both from the theoretical and practical point of view – has been given to the first part of this process. However, due to a newly developed instrumentation package, optimising froth recovery rates is now set to deliver real dividends. It is probably no exaggeration to say that the potential from augmenting froth recovery rates – in terms of what more efficient control of the level, residence time in froth, and pulling rates could deliver – was only truly recognised a few years ago by the industry.
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This is because it was incorrectly assumed that there are no losses during transport from slurry to the launder. It was only a few years ago that it was measured fully, and the results showed that the loses are typically 50% – reaching as high as 90% for coarse particles. What it means is that 50% of particles, averaging across all sizes, must be re-captured after becoming detached in the froth phase.
Simplifying a complex solution What if it were possible to increase the probability of recovery of particles in the froth phase, especially coarse ones? A good idea, but there is no simple way to put it into practice. It would require a combination of instruments and devices, more or less a froth-recovery instrumentation package, flexible enough to achieve this goal in the majority of flotation applications. A new and practical solution comes from the recognition that the combination of exact slurry level measurement and accurate control of flow using redesigned dart valves and new Festo actuators allows for better control of the froth phase. This in turn results in quicker reactions to flow and slurry density changes, which dramatically improves the performance of flotation machines.
The conventional way to influence froth recovery is a combination of changes to the froth height (improved by new actuators and dart valves), the froth crowding (in the middle of the cell, without the possibility of adjustment after installation, and not influencing the most active part of the froth surface), and the number of radial launders. All these changes are still possible while using a froth recovery package. The most difficult part is froth recovery at the end of the row, where there is not enough hydrophobic particles to form stable, deep froth, resulting in a large percentage of these particles being left unrecovered. The newly developed solution facilitates not only the recover of these particles, but offers the control required to balance recovery and grade in this part of the flotation circuit.
Harnessing the combined benefit of crowders, froth cameras, and actuators So overall, with the new solution, better results are achieved. Moreover, it also gives another degree of process control, not only during difficulties of froth formation, but during normal operation. This allows for more flexibility in selecting grade-recovery relationship. Central to froth recovery packages are adjustable radial froth crowders (ARFCs). ARFCs are mechanical devices that enable an increase of either recovery or grade, regardless of the amount of
froth formed at the top of the machine. They allow for much higher pulling rates (recovery) or much deeper froth (grade), which is currently hindered by the top of flotation machine geometry. In the case of FLSmidth, as well as ARFCs, which the company is capable of producing in-house, advanced froth cameras are provided in cooperation with Stone Three, a market leader in vision equipment. Froth cameras are a flotation instrument of central importance as they allow precise monitoring of the froth phase. By developing these cameras as the second key component of the package, working with a company such as Stone Three, FLSmidth is able to deliver a high quality product to the mining market. Alongside these elements are improved and redesigned actuators, developed by FLSmidth in cooperation with Festo, and a new and improved level sensor, which monitors both the slurry and froth positions with the MultiSense probe, provided in collaboration with HyControl. The final pieces of the package are redesigned dart valves (typically in a hinged dart valve configuration), which are the result of an in-house, value engineering project. With all these elements working together in combination with radial froth crowders (RFCs), this package delivers better recovery at the same grade or increased grade at the same recovery, making this package better than the sum of all its parts.
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Increased recovery and better grade The FLSmidth froth recovery package can be retrofitted into existing plants regardless of the type of mechanical cells: forced air or self-aspirated. This means the two major improvements provided by the package – controlled froth depth and the ability to either increase the pulling rate or froth depth with the addition of RFCs – are available to mine operators. The first improvement can be implemented for both rectangular and cylindrical cells for any type of application, while the second is only for cylindrical cells where the froth pulling rate is low – it does not make sense to install RFCs at the beginning of a row and in high pulling rate applications. So far, FLSmidth has observed positive results from its new solution. RFCs are a recent addition to its offering and they have already been installed in two concentrators, while installation in a third has just started. The first two installations have proven that the froth crowders add another process variable in shallow froth situations – they allow for a higher pulling rate, ‘squeezing’ the froth quickly into radial launders, or enabling the building of higher froth depth by reducing the froth area. A high pulling rate increases recovery, while a high froth depth increases concentrate grade.
Figure 1. FLSmidth flotation cells at a mine site in South America.
A second separate but significant development Much in the same manner in which the FLSmidth’s froth recovery upgrade package combines the benefits of different technologies to produce results that are greater than the sum of its parts, mingling two different types of cells – the nextSTEPTM forced air and WEMCO® self-aspirating – also returns dividends in terms of recovery levels. The cell-combination concept came about as the company sought to resolve challenges presented by older flotation systems, as well as ways to boost flotation productivity and reduce environmental footprint. The result was the mixedROWTM Flotation System, launched in late 2020. The mixedROW Flotation System is the first system of its kind on the market. It works by exploiting the characteristics of two flotation cell technologies at the same time. The nextSTEP machines are placed at the beginning of the row, where it can recover coarse material using the least amount of energy possible. Due to this positioning, the mixedROW lowers energy consumption by between 15 – 40%, and increases recovery by 1 – 3%, depending on the application. This improvement, even if it is not a large number, translates to very large economical gain, in many cases equal to tens of millions of dollars annually. The WEMCO machines are placed at the end of the row, which increases both coarse and fine particle recovery, as they are capable of treating a wide range of particle sizes. The elevated rotor position built into the machine design also reduces energy consumption, as the froth only has a short distance to travel. In addition to differences in hydrodynamics, absorbed energy and specific energy in the rotor region, both machines have different froth recovery mechanisms: nextSTEP has a very stable froth layer which can be very deep, while WEMCO’s froth is very dynamic (WEMCO wave). These differences also influence the type of particles recovered by both types of machines and add to the range of particles recovered by mixedROW. mixedROW also has the lowest head loss on the market, as its carefully engineered system of dart valves allows for efficient transfer of slurry from one tank to another without significant losses. mixedROW can be configured to suit whatever the customer needs may be. It can be adapted to whatever application it is needed for, making it a highly flexible and effective solution. Although only officially launched in 2019, there are already quite a number of installations where the mixedROW concept has been successfully applied. The first instillation was at Western Limb in South Africa, where WEMCO was retrofitted into a row of a competitor’s self-aspirated cells. This was followed by the first fully pre-planned and designed nextSTEP-WEMCO mixedROW at Mogalakwena, which, like Western Limb, was also a platinum group minerals (PGM) application. Interest in this solution has continued to grow, and the most recent examples have been: a retrofit at Antapaccay, followed by a mixedROW expansion (copper), and then two mixedROWs added at Toquepala (copper/molybdenum).
Looking to the future of flotation
Figure 2. Froth bubbles to the surface as part of the flotation process.
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In recent years, FLSmidth has participated in targeted collaborations with universities that have process knowledge and capability relevant to flotation. Last year, the company was approached to be the leading industrial partner in an application for an EU funded research project, with the aim of conducting
research to gain knowledge and understanding of flotation in mining, while benchmarking various flotation technologies. Flotation is a key process area with impacts on upstream comminution and downstream dewatering. There is huge potential to save energy and resources through the latest innovations in refining flotation process technology. These environmental benefits also support the FLSmidth MissionZero ambition to reduce emissions from mining towards zero by 2030. Helmholtz Center Dresden Rossendorf (HZDR) and FLSmidth recently proposed a project named ‘FlotSim’, with the goal of drastically improving the recovery rates of flotation through fundamental flotation analysis, and comparing the industrial state-of-the-art technologies to each other. This project received a 2020 Horizon grant.
Figure 3. Two FLSmidth flotation cells installed at a mine site.
This fundamental research, along with strong internal research and development (R&D) efforts, will advance existing and developing flotation products, including: forced air nextSTEP, naturally aspirated WEMCO, fast flotation REFLUXTM Flotation Cell (RFCTM), and coarse particle coarseAIRTM flotation cells. In addition to furthering fundamental understanding, these efforts will allow for improved simulation models and, subsequently, optimised equipment selection and flowsheet design. Improved next generation flotation processes are mandatory to remaining economically competitive and to ensuring sustainable mining for future generations. The FlotSim collaboration with industry and university partners, along with the recruitment of five early stage PhD research candidates, will address some of these important societal challenges. At the end of 2020, a second grant (the annual EIT RawMaterials KAVA Upscaling Projects grant) was awarded to a consortium of mine sites, chemical companies and universities, led by FLSmidth, to specifically upscale the aforementioned RFC technology. The goal is to upscale the RFC technology and accelerate commercialisation during the 3-year project. This will involve pilot and full scale testing, as well as eventual sales of full scale equipment for the copper and iron ore industries, among others. The innovative RFC technology, invented by Professor Kevin Galvin of the University of Newcastle in Australia, has an entirely new internal design compared to traditional flotation methods. The result is much higher throughput with simultaneously improved separation efficiency. The RFC is already proving that it can operate successfully outside of the limitations experienced by traditional open tank flotation systems. The technology has potential across various commodities and flotation applications. The opportunity presented by the work packages included in the EIT RawMaterials KAVA grant will accelerate the commercialisation of the technology. It will also allow for further development and optimisation of the RFC, which will further expand FLSmidth's suite of flotation product offerings. The consortium behind this upscaling project is led by FLSmidth and includes two mine sites (KGHM Polska Miedz Spólka Akcyjna in Poland and Luossavaara-Kiirunavaara AB [LKAB] in Sweden), two universities (Norwegian University of Science and Technology (NTNU) and Helmholtz Helmholtz-Zentrum Dresden-Rossendorf University), the Swedish Environmental Research Institute, and several external advisors. The University of Newcastle in Australia and Professor Kevin Galvin will act as two of the external advisors.
Conclusion
Figure 4. The mixedROW™ Flotation System.
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Flotation is a crucial part of the mining process, but it is also one that is resource intensive – using approximately 7% of a mine’s total electrical energy and significant amounts of water. This resource usage means costs for the operator, as well as creating waste that must be managed. As sustainability and a focus on resource usage join efficiency improvement as priorities for miners, the research and effort needed to optimise flotation are becoming increasingly important. Through new innovations, such as those detailed in this article, coupled with a high R&D focus, a more efficient and higher performing future for flotation seems to be bubbling nicely to the surface.
Wendel Rodrigues, Wagner Silva, Pierre Fernandes, Pedro Gonzaga, and Ronaldo Fonseca, Clariant, describe how using a new reagent suite can reduce the negative effects of aluminosilicate minerals on gold flotation.
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s a result of declining sulfide orebody quality, low grade and complex ores that were previously not economically feasible, such as transitional ores and former tailings, are now being considered for processing. The beneficiation of these ores is hindered by the presence of aluminosilicates – such as: kaolinite, chlorite, biotite, amphiboles, and montmorillonite. The various deleterious effects of aluminosilicates on flotation froth have been reported by numerous research studies, which show the aluminosilicate content influences on mining, operations, and processing of ores.1,2,3,4,5,6,7,8,9 Aluminosilicates affect mineral processing in grinding, froth flotation, thickening, dewatering, and in the final
disposal stages. The presence of aluminosilicates results in changes in slurry rheology. In flotation, aluminosilicates trigger a wide variety of problems, such as: increased reagent consumption by fine particles; low quality concentrate, due to silicate gangue entrainment; and recovery losses, possibly as a result of the formation of slime coating on air-bubbles or on mineral surfaces. In addition, aluminosilicate particles cause the flocculation phenomenon in the froth zone of flotation cells.4,10,11 On the other hand, gold and sulfide particles frequently occur as fine-grained inclusions (< 5 µm) in silicates, which do not present a satisfactory flotation performance with sulfhydryl collectors – such as xanthate, dithiophosphate,
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and thionocarbamate – due to low particle/bubble attachment efficiency.12,13,14,15,16 Several mechanisms have been proposed for the surface charge generation of various systems. For oxide minerals – such as hematite, quartz, and alumina – the origin of the electrical charge at the oxide surface/aqueous phase can be ascribed to protonation/deprotonation of the surface hydroxyls:17,18,19,20,21,22
of the modifier.18,19,23,24,25,26 In this study, a new approach was taken to improve the flotation behaviour of gold ores with high silicate content. This involved conducting studies using new reagents, in addition to the collectors and frothers conventionally used in sulfide flotation.
Experiments Ore samples
MOH(surf) – MO-(surf) + H+(aq) MOH(surf) + H+(aq) – MOH2+(surf) The mechanism of flotation of silicate and sulfide minerals are dependent on the electrical properties and the solubility of the mineral, the charge and chain length of the collector, and the stability of the salt metal-collector. In addition, the depressant and dispersant adsorptions are also related to surface mineral characteristics, such as: the chemical composition; the electrical charge distribution and solubility; the potential determining ions content in slurry; and the chemical and structural composition Table 1. Chemical analysis of gold ore sample Component
Assay
Gold
0.4 g/t
Sulfur
3.44%
Carbon
0.15%
Aluminium
6.78%
Magnesium
0.19%
Iron
5.22%
Silica
28.82%
The gold ore tested was comprised of predominantly gold bearing pyrite and arsenopyrite from the state of Minas Gerais in Southeast Brazil. X-ray diffraction (XRD) analysis showed that the ore has 6.1% sulfides (5.9% pyrite, 0.1% arsenopyrite, and 0.1% between chalcopyrite and pyrrhotite), 43.2% quartz, 30% muscovite, 5.6% feldspar (K-feldspar and albite), 2.8% other silicates (pyroxenes, amphiboles, and clays), 1.3% iron oxides, and 10.8% carbonates. The ore was first crushed to -3.36 mm in size prior to the grinding. After the crushing, the ore was ground to the particle size of 80% passing 0.12 mm. This ore sample was homogenised and then quartered to produce 1500 g fractions for the flotation experiments. Table 1 shows analytical results obtained on the head samples for the gold ore sample. Analysis of gold was carried out by fire assay and atomic absorption spectrometry (AAS), while the other elements were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The amount of total sulfur and carbon was determined using the technique of direct combustion and infrared detection (carbon and dual range sulfur analyser [LECO]).
Reagents Flotation tests of gold ore used Clariant FLOTIGAM® 7381 (alkyl etheramine) as a collector in addition to the collectors widely used in sulfide flotation, potassium amyl xanthate (PAX), and potassium diethyl dithiophosphate (DTP). These tests also used Clariant FLOTANOL® M28 (aliphatic alcohols and non-ionic reagent) or methyl isobutyl carbinol (MIBC) as frothers, commercial sodium silicate (SiO2/Na2O = 3.3) as a depressant, and lime to adjust the pH.
Figure 1. Clariant flotation conditions for gold ore with silicate presence.
Figure 2. Recovery of gold and sulfur with PAX, DTP, FLOTIGAM 7381 (F7381), sodium silicate (SS), and FLOTANOL M28 (M28).
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Experimental conditions and procedures Rougher flotation experiments were performed using a Denver laboratory machine with a 2 l flotation cell, in which 1500 g of gold ore samples and tap water were added to achieve the required pulp density. The impeller speed was 1200 rpm, the airflow rate was set at 5 l/min., and pH was adjusted with the addition of lime. The experimental conditions are shown in Figure 1, including reagent dosages (collectors, frothers, and depressant) and total flotation time. A total of four concentrates of gold ore were skimmed off at 1, 2, 4 and 9 minutes, in order to determine the flotation recovery as function of time.
Results and discussion The gold flotation recoveries in the presence of FLOTIGAM 7381, sodium silicate, PAX, and DTP are shown in Figure 2. The results indicate a sharp increase in gold and sulfur recoveries when using FLOTIGAM 7381 and sodium silicate. The gold recovery exceeded 80%, and the sulfur recovery rose from 60.9% to 84%. Figure 2 shows that thio collectors (DTP+PAX) or FLOTIGAM 7381 alone did not yield the best results. However, when thio collectors, FLOTIGAM 7381, sodium silicate, and FLOTANOL M28 were added together at pH 10.5, the gold and sulfur recovery both improved. These results reinforce the idea that Figure 3. Flotation recovery of gold as a function of time. both fine liberated sulfide particles and sulfide minerals associated with aluminosilicates and quartz, which can float with etheramines, must be floated in order to maximise gold recovery. The sulfide bearing mineral in this gold ore sample was predominantly pyrite, but only 30% was fully liberated, while 34% was associated with silicates (quartz, muscovite, K-felspar, and others) and 36% was associated with other minerals, such as: phosphates, metal oxides, and carbonates. Despite the low arsenopyrite presence, gold particles were identified in this mineral, which presents 43% of particles fully liberated and 57% associated with other minerals (phosphates, oxides, and Figure 4. Species distribution of FLOTIGAM 7381 as a function of pH carbonates). (initial concentration of etheramine = 1.10-4 mol/L). Figure 3 compares rates of gold flotation when only thio collectors (PAX and DTP) are used with the surface product on gold and iron-bearing species, providing addition of FLOTIGAM 7381, FLOTANOL M28, and sodium the hydrophobic character to these sulfide particles. silicate in pH 10.5 as well as PAX and DTP. It can be On the other hand, the amount of thio collectors observed that the addition of FLOTIGAM 7381, adsorbed on the surface of sulfide-silicate mineral FLOTANOL M28, and sodium silicate strongly improved the associations and locked gold particles in silicate minerals gold flotation performance compared to the addition of may not be sufficient to overcome the detachment forces only thio collectors (PAX and DTP). The new reagent inside the flotation cell. Therefore, the addition of scheme reached gold recoveries greater than 80% at FLOTIGAM 7381 rendered the formation of a more packed 4 minutes, while the gold recovery with only thio collectors layer of collector molecules on the surface of sulfide-silicate did not exceed 40%. mineral associations, which enhances their hydrophobicity, Indeed, once there is a thermodynamically favourable and thus results in flotation performance improvement. The environment for flotation of sulfide liberated particles and species distribution diagrams of FLOTIGAM 7381 as a those associated with aluminosilicate and quartz, this ore function of pH at the bulk total concentration of 1.10-4 mol/l are shown in Figure 4. The values of the thermodynamic type can be selectively recovered. Firstly, xanthate and equilibrium constants of the etheramine were determined dithiophosphate were adsorbed on the sulfide surface, via a using titration curves, in order to calculate the respective strong electrochemical mechanism. In fact, the ionic and molecular species concentrations of the collector chemisorption results in the formation of a hydrophobic
at various pH values. FLOTIGAM 7381 showed pKa1 and pKa2 of 4.7 and 8.9, respectively, and pKsol of approximately 4.9. Based on Figures 3 and 4, it appears that an ion-molecular species complex of etheramine is responsible for the flotation performance improvement of the sulfide-silicate associations and locked gold particles in silicates, because the adsorption of its ionic and molecular species on the silicate surfaces causes an increase in the attachment efficiency for the gold ore sample. Moreover, sodium silicate was able to depress aluminosilicate and quartz particles, fully liberated or with an insignificant amount of sulfides or gold, due to the adsorption of silicate species (Si(OH)4 and SiO(OH)3-), which are predominant at flotation pH > 10. These silicate species can penetrate the innermost water layer and react with surface sites of silicate minerals, which improves the flotation selectivity.
Conclusions From this study, one may conclude: Xanthate (PAX) and dithiophosphate (DTP) can be used to hydrophobise sulfide minerals, such as pyrite and arsenopyrite. However, the thio collectors are not able to provide a sufficient degree of hydrophobic coverage on
the sulfide particles associated with silicates and locked gold particles. The addition of FLOTIGAM 7381 leads to higher gold recovery, due to the adsorption of the etheramine on the silicate surface. Thus, the ionic and molecular species presence of FLOTIGAM 7381 can enhance the attachment forces, through the concentration increase of collector species on the surface of sulfide-silicate mineral associations and silicate minerals with locked gold. Despite the promising recovery, the selectivity of the flotation process may be jeopardised by the significant increase of collector species onto the flotation cell. However, the sodium silicate reduces the flotation rate of fully liberated silicate particles and those with a small amount of sulfide minerals. Gold ores that contain silicates minerals – such as quartz, muscovite, clays, chlorite, and amphiboles – can suffer significant losses of recovery. This is due to low hydrophobicity levels in the sulfide-silicate mineral associations and locked gold particles in the silicates. On the other hand, these recovery drops can be overcome by the addition of FLOTIGAM 7381 and sodium silicate, which constitutes a new concentration route for this kind of ore.
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