Tag Archives: PGMs

Zest WEG carrying out EC&I works at Anglo Platinum’s Mogalakwena CPR plant

Zest WEG is installing a range of electrical control and instrumentation equipment at Anglo American Platinum’s Mogalakwena mine in Limpopo province, South Africa, working closely with engineering group DRA Global.

The construction is taking place within the Mogalakwena mine’s existing North Concentrator Plant, around various plant areas. The Electrical Control Instrumentation (ECI) package is being led by Eben Kleynhans, E&I Electrical Project Engineer from DRA.

According to Calvin Fisher, Electrical and Instrumentation Construction Proposals Manager at Zest WEG, the Zest WEG work is being conducted for the mine’s Coarse Particle Rejection (CPR) plant, and will be completed in the second half of 2021.

“In addition to applying the highest level of workmanship and professionalism, we are carrying out the project in line with our client’s Mining Charter requirements on local procurement,” Fisher says. “This means that over 70% of people involved in our scope of work will be drawn from local communities, and we are sourcing a significant level of our supplies from local businesses.”

Equipment to be installed includes three 2 MVA transformers, stepping down from 11 kV to 550 V, and a 630 kVA mini substation for lighting and small power requirements. Containerised motor control centres (MCCs), complete with variable speed drives (VSDs), an HVAC unit, cable racking, cables, lighting and small power also form part of the scope of supply. In addition, two back-up generators will be installed – one of 630 kVA capacity and the other 330 kVA.

“The three new containerised MCCs and VSD sets will be placed on plinths near the CPR feed tank, CPR process water area and CPR building and a steel roof structure erected over the containers,” he says. “The new transformer bay will be constructed next to the MCC, also with a roof over the transformer.”

About 70 km of cable will be laid – ranging from low voltage to medium voltage cable – as well as 3,300 terminations and almost 2.5 km of cable racking. The various structures that Zest WEG will install require some 9 t of steel. The instrumentation to be installed will comprise about 170 instruments including flow transmitters, pressure gauges, level switches, temperature gauges and density transmitters. There will also be around 250 lights installed, mainly outdoors.

Fisher notes that the electrical installation specialists are typically among the last contractors on a project, and must be quite flexible to accommodate certain modifications that may have been required in the civils, structural and mechanical work completed beforehand.

“Wherever necessary, we work closely with the client to implement the plan smoothly while meeting their need for safe access to the equipment being installed, to allow maintenance to be readily conducted,” he says.

In addition to the installation contract, Zest WEG is supplying some of the actual items of equipment for the expansion project, including WEG motors and containerised generators. The electrical installation work is expected to take about six months.

“We are proud of the high level of quality that we bring to projects like this, where we apply our successful model of procurement to support our clients in meeting their critical local expenditure targets,” he says. “This also allows Zest WEG to make a valuable contribution to uplift local companies wherever we can.”

Scantech launches GEOSCAN GOLD to help digitalise and control ore quality

Scantech International Pty Ltd has released GEOSCAN GOLD, a premium elemental analyser that, it says, uses the highest specification PGNAA (prompt gamma neutron activation analysis) technology available.

The analyser, which builds on Scantech’s GEOSCAN-M high-performance elemental analyser, provides previously unattainable levels of risk-free, real-time measurement performance to the resources sector to help digitalise and control ore quality, according to the company.

GEOSCAN GOLD provides high-quality, real-time elemental analysis for conveyed flows where precision and short measurement times are essential for optimal control. This makes it ideal for bulk diversion (bulk sorting) and fine control where elements at parts per million levels need to be measured or determined from proxies such as gold, platinum group elements, silver and toxic contaminants (eg mercury, cadmium, chlorine, etc), Scantech says.

The analyser incorporates a high performance proprietary detector array for a “better, cleaner spectrum” at lower concentrations for superior element recognition. The array overcomes limitations of conventional, low efficiency detection systems, according to Scantech. It can also operate at extremely high count rates with negligible pulse pile-up.

“This innovation vastly improves the signal to noise ratio and spectral peak resolution, enabling elemental detection at lower levels,” the company said.

Just some of the advantages of GEOSCAN Gold that Scantech highlighted include:

  • An ultra-compact design that can install between standard idlers;
  • Unmatched proven performance;
  • Operational at completion of commissioning;
  • Customised calibrations;
  • Three models cater for belts 600 mm to 2,400 mm and bed depths to 530 mm;
  • No contact with material or conveyor belt;
  • No sampling necessary during normal operation;
  • No wear parts, therefore, low maintenance requirements;
  • Optional customised SUPERSCAN console;
  • Interface to most process control systems; and
  • Proven short paybacks in many applications (bulk diversion, blending, monitoring, feed forward, etc) to optimise plant performance.

The company says GEOSCAN GOLD measures elements in primary crushed rock in conveyed flows at <100 t/h to >10,000 t/h irrespective of belt speed, particle size, mineralogy, dust, moisture, or segregation/layering,

It covers most elements from carbon onwards in the periodic table, including gold, over various measurement times and concentration levels. It can also analyse selected elements to below 1 parts per million, and even register accurate results where conveyor belts contain chlorine or steel cords.

It can register gold directly over 5-10 minute increments and other elements, including proxies for gold (eg sulphur, copper, etc), with high precisions over each 30 seconds of flow.

Measurement data is used concurrently for various applications: bulk sorting, ore blending, ore reconciliation, ore tracking, feed forward control, metal accounting, etc.

“GEOSCAN GOLD is the new standard in representative, real time, conveyed material measurement using Scantech’s Rocks2data customisation module,” the company said. “Successful performance is already proven in many challenging bulk ore sorting applications in base metals and PGMs. It builds on the very successful, world-leading GEOSCAN-M with over 100 installations in the minerals sector in more than 10 commodities. Paybacks are in a few months and sometimes weeks. Non-contact design minimises maintenance and remote access ensures trouble-free operation and high data accessibility.”

Nornickel backs responsible sourcing and production practices with blockchain agreement

Norilsk Nickel says it is joining the Responsible Sourcing Blockchain Network (RSBN), an industry collaboration among members across the minerals supply chain using blockchain technology to support responsible sourcing and production practices from mine to market.

The move to join RSBN comes after Nornickel announced a broad strategy to use sophisticated digital technologies to create a customer-centric supply chain, which would include metal-backed tokens on the global Atomyze platform, a tokenisation platform that represents physical assets in digital form. Both the Atomyze and RSBN platforms were developed by leveraging Hyperledger technology, with IBM’s participation, the PGM and base metal miner said.

With Nornickel joining the RSBN, a series of its supply chains will be audited annually against key responsible sourcing requirements by RCS Global. The audits cover each stage of the company’s vertically integrated operations from mines in Russia to refineries in Finland and Russia.

Once audited against responsible sourcing requirements, each supply chain will be brought on to the RSBN and an “immutable audit data” trail will be captured on the platform, proving responsible nickel and cobalt production, its maintenance and its ethical provenance.

“Integration with RSBN is yet another step for Nornickel towards achieving greater business sustainability by creating a permanent record of minerals on the blockchain,” the company said.

At a later development stage, data such as upstream carbon intensity and other ESG attributes will be tracked, it added.

Built on IBM Blockchain technology and powered by the Linux Foundation’s Hyperledger Fabric, the RSBN platform helps improve transparency in the mineral supply chain by providing a highly secure and immutable record that can be shared with specified members of the network, Nornickel says. Additionally, RCS Global Group assesses each participating entity both initially and annually against responsible sourcing requirements set by the Organization for Economic Cooperation and Development and those enshrined by key industry bodies, including the Responsible Minerals Initiative.

Anton Berlin, Nornickel’s Vice President, Sales and Distribution, said: “As one of the largest industry groups globally and the producer of the minerals essential for the transition to a carbon-free world, Nornickel is well aware of its responsibility to make the metals supply chains sustainable and highly transparent. We believe that the digital technologies of RSBN and Atomyze will create the path for Nornickel and its partners to participate in a circular value chain, tracing commodity flows in near real time as well as replacing cumbersome paperwork.”

RCS Global CEO, Dr Nicholas Garrett, added: “The RSBN has proven that responsible sourcing can be traced and documented using blockchain technology. Assuring Nornickel’s supply chains is another milestone engagement for RCS Global and Nornickel’s commitment to the RSBN and demonstrates momentum for blockchain backed responsible sourcing platform in the metals sector.”

Manish Chawla, Global Managing Director, Chemicals, Petroleum & Industrial Products, IBM, said: “Norilsk Nickel is an important addition to the Responsible Sourcing Blockchain Network and we look forward to their contributions to help advance the assurance for responsible sourcing and the group’s sustainability goals that have a direct impact on successful and accountable development for entire industries.”

RSBN is designed to be adopted across industries by original equipment manufacturers in automotive, electronics, aerospace and defence as well as their supply chain partners such as mining companies and battery manufacturers.

Sedibelo Platinum to expand PPM operations and leverage Kell Technology

Sedibelo Platinum Mines has announced plans to expand its Pilanesberg Platinum Mines (PPM) operation on South Africa’s Bushveld Complex, as well as construct a 110,000 t/y beneficiation plant at PPM employing Kell Technology.

The company plans to mine the three contiguous deposits of Sedibelo Central, Magazynskraal and Kruidfontein – known as the Triple Crown properties – as part of the expansion. These three come with an estimated resource base in excess of 60 Moz of 4PGE.

The predominantly shallow deposits will enable safe and sustainable mining activities for potentially more than 60 years, according to the company. The approved expansion will be funded through Sedibelo’s existing cash resources and future cash flow, with first ounces from Triple Crown expected to be extracted in 2023.

The Triple Crown expansion will be mined simultaneously with ore from the existing open-pit UG2 and Merensky operation, using two separate decline shaft systems, the company said.

The existing PPM concentrator plant has the capacity to be used to process the Triple Crown ore as well as ore from the open pits. With minimal reconfiguration, the Triple Crown UG2 and Merensky ore will be blended and processed through the existing Merensky plant, thereby reducing capital expenditure as well as lowering operating cost significantly, it said.

Speaking of the 110,000 t beneficiation plant, Sedibelo said Kell Technology reduces energy consumption by some 82% with the associated significant reduction in carbon emissions, also improving recoveries and lowering operating costs.

“Benefitting from being robust in operation, Kell is unconstrained by concentrate grade, is insensitive to chrome levels as well as being resistant to other impurities,” it explained. “Hence, using Kell will improve the economic return of the Triple Crown expansion and is an integral part of Sedibelo’s future development.”

As applied to treatment of PGM concentrates, the Kell Process comprises four main unit operations (pressure oxidation, atmospheric leach, heat treatment and chlorination), all of which are conventional and in commercial use in the minerals and metals industry.

Sedibelo shares an interest in Kell South Africa with the Industrial Development Corp and Founder Keith Liddell, through Lifezone.

Arne H Frandsen, Chairman of Sedibelo, said: “Today is a significant day in Sedibelo’s history. We are opening our next door 60 Moz Triple Crown deposit, thereby securing the future of Sedibelo for many decades to come. The construction of our Kell plant will allow us to produce metal and lower our cost profile further. Equally important, it will reduce our carbon footprint and water usage significantly.

“We trust our environmentally friendly platinum group metals will become an important part of future electrification and the ‘green revolution’ used in fuel-cells around the world.”

Keith Liddell, Founder of Kell and CEO of Lifezone, said: “I developed Kell Technology as a cost-efficient alternative to the conventional smelting of PGMs. We are excited to now proceed with the construction of the Kell plant at PPM. The benefit for Sedibelo and the industry will be significant; delivering beneficiation, energy and cost advantages as well as a reduction in CO2 and SO2 emissions.”

Atlantic Nickel ready to delve underground for Santa Rita mine life expansion

Atlantic Nickel has released a preliminary economic assessment (PEA) on its Santa Rita nickel mine, in Brazil, that shows the potential for the company to become one of the largest sustainable nickel sulphide producers in the world.

The announcement, made in concert with Appian Capital Advisory LLP (the owner of Atlantic Nickel), follows the recommencement of open-pit mining at Santa Rita in August 2019.

This new NI 43-101 technical report outlines a 34-year mine life for Santa Rita, in Bahia, with eight years of open-pit production, underpinned by proven and probable reserves of 50.6 Mt at 0.31% NiS, and 26 years of underground mining.

The open-pit mine plan was prepared to prefeasibility study level and encompasses a large open pit and a nearby, much smaller satellite open pit along strike. Both pits will be mined with conventional mining equipment, and the plan will be executed in 10 phases, the company says.

The open pit is scheduled over a period of eight years, ending in 2028, with operations using standard methods of drilling and blasting, loading, and hauling. It would produce 20,000-25,000 t/y of contained nickel equivalent at a C1 cost of $2.97/lb Ni and an all-in sustaining cost (AISC) of $4.12/lb Ni, the company says.

The Santa Rita process plant, having started production in 2009, was completely refurbished and recommissioned in the second half of 2019 in line with the mine restart. The plant consists of crushing, grinding, flotation, thickening and filtration unit operations to produce a saleable nickel concentrate. Flotation tailings are pumped to a tailings storage facility, while grinding is performed by a SAG mill, two ball mills and two pebble crushers. This is followed by a conditioning circuit and a flotation circuit, with the final concentrate thickened and pumped to storage tanks ready for filtration. Concentrate is filtered in a Larox (Metso Outotec) pressure filter. Following filtration, the final concentrate is trucked to the port of Ilhéus where it is loaded onto ships for transport to market.

The mineral resource estimate for the expansion case consists of 94.2 Mt of measured and indicated resources across open-pit and underground mining at average grades of 0.41% NiS, 0.14% Cu, 0.01% Co, 0.03 g/t Pd, 0.07 g/t Pt and 0.05 g/t Au, with 90.6 Mt of inferred resource at 0.54% NiS, 0.17% Cu, 0.02% Co, 0.04 g/t Pd, 0.09 g/t Pt and 0.06 g/t Au.

Sublevel Caving (SLC) was selected as the mining method for the underground portion of the deposit based on the amenable geometry of the deposit, and because productivity and cost advantages of SLC enable greater exploitation of the underground resource at greater margin than more selective mining methods, Atlantic Nickel said.

“The geometry of the deposit and the location below a mined open pit are similar to the Ernest Henry SLC, which is successfully operated by Ernest Henry Mining (a subsidiary of Glencore) in Queensland, Australia,” the company added.

The SLC mining method employs long-hole drilling and blasting techniques to extract mineralisation sequentially from the surface to the bottom of the deposit. The method does not require backfill and, therefore, relies on the overlying waste rock to cave and fill the mined void, the company explained. Caving of the overlying waste rock results in surface subsidence above and in the immediate vicinity of the underground deposit, but the subsidence will not interfere with open-pit mining since initial production from underground is planned to commence in 2028 when open-pit mining is completed.

Infrastructure capital and development of the underground project is planned to start at the beginning of 2026, with production from the underground ramping-up over a seven-year period until full production of 6.2 Mt/y is achieved.

The underground portion of the resource considered in the PEA plan consists of 43.5 Mt of indicated resources and 90.6 Mt of inferred resources. This resource was used to come up with a 40,000-45,000 t/y of contained nickel equivalent production profile for the underground operation over life of mine at a C1 cost of $2.17/lb Ni and an AISC of $3.92/lb Ni.

The SLC mining layout in the PEA comprises 37 mining levels spaced at vertical intervals of 25 m. Each level is made up of parallel and evenly spaced drill drives from which production drilling and blasting occur. Once blasted, the mineralisation is loaded from the drill drives using LHDs and loaded into trucks for haulage to the surface during the initial ramp-up phase, and later to ore passes feeding an underground crushing station and conveying to surface via an inclined tunnel.

“The SLC method employs a top-down mining sequence that enables production to ramp-up quickly once the top of the underground deposit has been accessed,” Atlantic Nickel says. “The method also enables high production rates as the mining cycle is simplified by the standardisation of development and production and with no backfilling required.”

While still early days in terms of the underground mine’s development plans, the company assumed the use of automated LHDs, longhole drilling and jumbo development drilling in the PEA, a spokesperson for Atlantic Nickel confirmed to IM. This saw Epiroc and Sandvik provide price inputs, with design layouts anticipating such equipment.

“Subsequent studies will optimise the equipment and layouts integration,” the spokesperson added.

And, while the current study assumes the use of a diesel-powered fleet, battery-electric vehicles will also provide upside in future studies and further reduce energy costs, equipment maintenance costs and ventilation power costs, the spokesperson said.

“Both tethered and battery will be look at for specific applications within the mine such as loading from drawpoints and feeding the underground crusher from the bottom of ore passes,” the spokesperson said.

The flotation test work gave similar results to those obtained with open-pit material; hence, plant performance is not expected to be significantly different for underground material, the company said. Underground feed will be treated in Atlantic Nickel’s existing process plant with only minor modifications required, likely to the grinding circuit.

New surface infrastructure associated with the underground mine would include the following:

  • A box cut and portal located to the west of the north end of the open pit;
  • A conveyor portal connecting to the bottom of the existing crusher installation;
  • A temporary construction portal in the west wall at the north end of the open pit on the 82 m RL bench;
  • Multiple ventilation raise surface collars on the western side of the open pit;
  • Ventilation adits on the west wall at the south end of the open pit on the 10 m RL bench;
  • Dewatering pond for storing, settling and recycling water from underground;
  • Electrical reticulation to the portals, adits and services; and
  • Shotcrete batch plant.

After completion of open pit mining, a new tailings storage facility would be required to store the additional 134 Mt of tailings to be produced from the underground mine over a period of 28 years. Like the existing tailings storage facility, raises will be constructed using a downstream method, the company said.

Total capital associated with the underground expansion amounts to $1.3 billion over the 34-year combined operation, with only $355 million of that being spent during the first five years of underground development commencing in 2026. The expansion is partially self-funding with cash flows generated from the open-pit mining operation, the company said.

DRA Global to help debottleneck Anglo American Platinum’s Unki PGM concentrator

DRA Global says it has been awarded an engineering procurement and construction management contract to expand Anglo American Platinum’s Unki platinum group metals concentrator, in Zimbabwe.

The engineering company was previously enlisted to carry out a feasibility study on the expansion, referred to as the “debottlenecking” project by Anglo American Platinum, and will now help increase throughput capacity to 210,000 t/mth, it said.

The Unki concentrator, built in 2010, can currently treat up to 180,000 t/mth according to Anglo American Platinum. It processes material from the Unki mine, one the world’s largest PGM deposits outside of South Africa, the miner says.

Anglo American Platinum, in its 2019 results released earlier this year, said it had signed off on the R700 million ($39 million) debottlenecking project and expected commissioning to be completed in the September quarter of 2021.

Unki has steadily been ramping up production in recent years. In 2019, it produced a record 202,000 oz of platinum group metals, up from 193,000 oz in 2018 and 166,000 oz in 2017.

Robit drilling consumables in transit to Norilsk Nickel

Robit says it has signed a contract to supply drilling tools to Norilsk Nickel, in Norilsk, Russia, with the deliveries expected to take place during April and May.

Norilsk is in Krasnoyarsk Krai, Russia, and located above the Arctic Circle. Since there are no roadway or railway connections, all freight is delivered by cargo ship via the Arctic Ocean to the Port of Dudinka, in Murmansk, or by air. The Robit drilling consumables are to be delivered by sea, Robit said.

Norilsk Nickel is one of Russia’s leading metals and mining company, a manufacturer of palladium and refined nickel, and one of the biggest platinum and copper producers in the world. The company also produces cobalt, rhodium, silver, gold, iridium, ruthenium, selenium, tellurium, and sulphur.

Robit, meanwhile, provides drilling consumables for applications in mining, construction and contracting, tunnelling, and well drilling. It has two product and service ranges: top hammer and down-the-hole.

Last month, the company signed a two-year contract to supply drilling tools to Al Masane Al Kobra Mining Co, in Saudi Arabia, for underground jumbo rigs at its Al Masane copper-zinc mine. The tools are to be supplied by Robit’s distributor, Bin Harkhil.

In February, Robit delivered its first consignment of rods for underground drilling to Ma’aden’s Al Amar underground gold-copper-zinc mine, in Saudi Arabia.

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

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

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

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

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

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

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

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

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

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

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

Water/heat

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Shifting commodity demand

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Twin Metals looks to avoid tailings dam concerns with dry stacking plan

The developer of the Twin Metals project, in the Iron Range region of northeast Minnesota, USA, has announced plans to use dry stacked tailings at the underground copper, nickel, platinum, palladium, gold and silver asset as the company looks to eliminate the perceived risk of a dam leakage or failure.

Twin Metals Minnesota (TMM), a company owned by Antofagasta, said the dry stack method eliminates the storage pond and dam associated with conventional tailings facilities and has been successfully used in four mines in the northern US and Canada with similar climates to Minnesota.

In 2018, an update of the prefeasibility study for Twin Metals outlined a 18,000 t/d ore project, producing an average of 42,000 t/y of copper, plus nickel and platinum group metals as by-products, the equivalent of some 65,000 t/y of copper.

TMM, like many other potential mine developers, said community concerns about copper-nickel mines have focused on fears of tailings dam failure or leaks that could threaten both nearby surface water and groundwater. This comes after several high profile dam failures in North and South America.

If all goes to plan, the company will use the dry stack method to store the leftover rock from its proposed underground mine on a lined ground facility near the plant site. This will allow reclamation of the tailing site to occur in stages, with the site capped or covered with natural vegetation.

Kelly Osborne, Chief Executive Officer of Twin Metals Minnesota, said: “Dry stack tailing storage is the most environmentally friendly tailings management approach for our site. The first key is that there’s no dam, no risk of dam failure. The moisture content of the filtered tailings is reduced to a material that we can compact and manage seasonally.

“Because there’s no risk of a dam failure, dry stack is considered the best available technology for tailings storage and, after a decade of study and consultation with concerned voices in our community, we determined that it will be an effective choice for our project.”

Equally important, TMM said, is the fact that the tailings from the Maturi deposit at Twin Metals will be non-acid-generating.

“The common concern about sulphides points to a basic misconception about our project,” Osborne said. “The geology of the Maturi deposit provides us with confidence that we can mine here safely and sustainably. The rock sandwiching the layer of copper, nickel and platinum group minerals in the deposit is almost completely free of sulphides. When the targeted minerals are removed during the concentration process and shipped to customers, only a minute amount of sulphides will remain in the tailings.”

Extensive testing over the past decade shows that Maturi deposit tailings will be non-acid-generating, the company clarified.

Dry stack tailings storage has been an option under consideration since Twin Metals began mine planning in 2010, the company said. “As technology has continued to advance, and the application of dry stack in cold, wet climates has proven successful at multiple locations, Twin Metals made the decision to move to it as the best available option,” TMM said, adding that The Minnesota Center for Environmental Advocacy hailed the advantages of dry stack tailings in a statement earlier this year.

Osborne concluded: “Dry stack is one of the ways we are making a 21st century mine that will be the most technologically advanced mine in Minnesota’s history and a model of how copper mining can be done safely and sustainably.”

The approach will be outlined in detail in TMM’s Mine Plan of Operation, to be submitted to state and federal regulators in the coming months. Regulatory review, including hearings for public comment, will cover compliance with regulations to protect water and air quality, drinking water, wetlands, endangered species, plant life and cultural resources. While the MPO is being reviewed the company will advance the feasibility study.

After reaffirming Twin Metal’s right to renew its two federal mineral leases, the Department of Interior reinstated the leases to TMM in May 2018. Antofagasta expects these to be renewed during 2019.

Anglo American’s FutureSmart Mining on its way to tangible technology results

“It’s clear that the pressures on us are unsustainable, whether it is around our carbon footprint, water footprint, or physical footprint, and we are always looking for different ways to push us in this future direction where our footprint will be very different.”

Tony O’Neill, Anglo American Technical Director, knows the company he works for is up against it when it comes to retaining its reputation as one of the world’s leading sustainable mining companies.

It’s clear from the company’s 2018 sustainability report – which saw it achieve a best-ever performance in terms of injuries, a cut in energy use and an increase in greenhouse gas emission savings – that Anglo is going down multiple paths to reach its goals. O’Neill, who joined the company almost six years ago, believes Anglo’s FutureSmart Mining™ programme will play a major role in confronting and overcoming many of the issues it (and the industry) is facing.

“If you look at FutureSmart Mining, at its absolute essence, it is about footprint; how do you change the footprint of mining? How do you have a mine that draws no fresh water? Mines without tailings dams? Mines that look very different?” he told IM.

“It’s getting people to believe there is a different way for mining in an industry that has, to this point, been quite traditional. It is not going to happen overnight, but I think we have a genuine vision that is, in my view, quite feasible.”

IM spoke with O’Neill and Donovan Waller, Group Head of Technology Development, this week to get to the bottom of how technology is making Anglo ever more sustainable.

IM: Could you explain how the Anglo operating model facilitates and fosters innovation within the context of FutureSmart Mining?

TO: The Anglo American operating model is the chassis that underpins everything, giving us certainty in the delivery of our work. When you have got that stability – and the lack of variability – in your business outputs, it is much easier to overlay new technologies and processes. When you then see a difference in operating or financial results, you can confirm it is down to what you have implemented, rather than the underlying processes.

I look at it a little bit like a three-legged stool: you have the operating model on one leg, the P101 benchmark-setting on another, and technology and data analytics on the third leg. They all co-exist in this system and work off each other. Without one, the stool falls over.

The operating model has given us a drumbeat of delivery, and we get the licence to innovate because of this drumbeat.

IM: Do you think FutureSmart Mining is starting to be understood and valued by investors?

TO: They’re awake to it now. I think it is still in the early stages of the story, but they can see what we are doing and the ambition behind it. Ultimately, it will result in a different investment profile, or more investors because of it, but I am not sure that it’s translated in full up to now. The recognition has been more around the general results of the company.

With all these technologies coming through – much of them driven by higher levels of data and the ability to interrogate that data – the vision we imagined way out into the future, I think, is a lot more tangible than when we started out four years ago.

IM: Out of all the tailings dam elimination work you are carrying out (around passive resistivity, fibre-optics, micro-seismic monitoring, coarse particle recovery, polymers, and dry stacking), which innovation will have an impact on Anglo’s operations in the next three-to-five years?

TO: All of them. We started out with our tailings programme in 2013; in fact, our group technical standards were re-issued at the beginning of 2014 and they are now one of the main guidelines the ICMM (International Council on Mining and Metals) uses.

Tailings dams have always been at the back end of the mining process and, in a way, the science behind them has never been part of the mainstream operation. Our view, internally for many years, is tailings dams are one of the industry’s greatest risks.

“Our view, internally for many years, is tailings dams are one of the industry’s greatest risks,” Tony O’Neill says

Ultimately our aim is to eliminate tailings dams. Period. Coarse particle flotation – getting that coarser particle size that drains much more freely – is core to that and you can see a development pathway there. For example, with some of these new flotation techniques, we now only need 1% exposure of the mineral for it to be effective. In the past, it was much higher.

When we upgraded the capability of our tailings organisation, it became clear we needed to get a lot more data off these tailings dams. About three years ago, we started putting fibre-optic sensors into the dams. We have since developed, through our exploration arm, passive resistivity seismic monitoring, which basically tells you where your water sits in the dams. And, we’re putting into Quellaveco micro-seismic measuring techniques, which will be more granular again. You can see the day coming really quickly where tailings dams are a real-time data source for mining companies.

We’re also, with our joint venture partner Debswana, building the first polymer plant in Botswana, which could have an impact on dry tailing disposal.

The thing we need to crack – both ourselves and the industry – is how to dry stack at scale. At the moment, that is still a work-in-progress, but it is doable in the long term.

IM: How is the bulk sorter you have operating at El Soldado, which is equipped with a neutron sensor, working? How has it made a difference to recoveries and grades at the operation?

TO: With the bulk sorter, we’re taking packages of tonnes rather than individual rocks to enable us to get both speed and volume. At El Soldado, we are sorting in four tonne packages. You can adapt the sorting profile by the characteristics of the orebody. We’re generally looking to sort tonnages that are less than you would put in a haul truck body or bucket.

If you step right back, in the past, most processing plants wanted to blend to get an average feed. We are going the other way. We want to use the heterogeneity of the orebody to its advantage; the less mixing we can get ahead of these sorting processes, the better it is for recoveries.

Being able to remove an orebody above the cut-off grade alongside waste tonnages and upgrade the latter has led to an effective lift in head grade. It has been enabled by new sensing technology with a particular type of neutron sensor.

What we have seen in early results has surprised us on the upside. We thought we would see a 5% uplift in head grade, but in fact we have seen about 20% – to qualify that, it’s in its early stages.

O’Neill says the bulk sorting trial at El Soldado has seen about a 20% uplift in head grade in its early stages

If you take this to its logical conclusion, you can see the day coming where you would cut the rock – no drilling and blasting – immediately sort the rock behind the machine cutting it and distribute said rock efficiently into its value in use; you don’t have stockpiles, you have plants sensing the material right through and adapting in real time to the change in mineralogy. I think there is another 3-4% increase in recovery in that whole process when we get it right.

Our sweet spot when we created FutureSmart Mining was always the orebody and processing plants, more so than automation (although that is part of the potential mix). That was different to a lot of the other players in the industry. This focus could lead to the development of different types of plants; ones that are flexible, more modular and you can plug and play.

IM: Do you see these type of neutron sensors being applied elsewhere across a mine site?

TO: Yes, through processing plants and conveyors. In fact, we’re preparing for this on conveyors right now.

What we have found with all this new technology is that, when we implement it, quite often another opportunity arrives. They end up playing off each other, and that is the context for the bulk sorting and coarse particle flotation.

IM: How have Anglo’s Open Forums played into these developments?

TO: We have held eight Open Forums on sustainability, processing, mining, exploration (two), future of work, energy and maintenance.

Out of those eight, I think we have got around 10,000 ideas from them. These forums have been specifically designed where only about a third of participants are from the mining industry, with the other two thirds coming from the best and brightest analogous industries we can tap into – automobile, oil & gas, food, construction, even Formula 1 racing and NASA.

The reality is that out of those 10,000 ideas, the success rate is about 1:1,000, but the one that makes it is quite often a game changer.

IM: Going back to the bulk sorters, am I right in thinking you plan to put these into Mogalakwena and Barro Alto too?

TO: The aim is to have them across our business. At El Soldado, the copper angle is very important. The technology – the sensing and using the data – is probably a touch more advanced in copper, but we are building one currently in our PGMs business at Mogalakwena and a bit behind that, but ready to be built, is one in nickel, yes.

In terms of our programme, you will see them spread across our business in the next, hopefully, 18 months.

IM: Where does your approach to advanced process control (APC) fit into the FutureSmart Mining platform?

TO: We want to have APC in some form across all our business by the end of this year. We have probably come from a little behind some of the other players in the industry, but we’re pushing it quite aggressively to give us the platform for data analytics. The upside we have seen just by putting the process control in so far has surprised me a bit – in a good way; power reductions, throughput, having this different level of control. All of it has been pleasing.

We spent about 12 months looking at the whole data analytics space to see how we were going to implement our solution. If you look around at the sector, everyone wants to be involved and profit share. If you add it all up, you could end up with not a lot of profitable pieces at the end. We have strategically chosen the pieces we think are important to us and our profit pool and have been happy to be a little looser on some of the non-core areas.

The other key plank to the APC is that we own the data. The reality is, in the new world, data is like a new orebody and we’re not willing to let go of that.

IM: Your Smart Energy project involving a haul truck powered on hydrogen has certainly caught the attention of the market: how did you come up with this innovation?

TO: Initially, we couldn’t make renewables work from an investment criteria perspective – it was always close, but never quite there. Donovan’s team then took an approach where they said, ‘forget the normal investment criteria. All we want to do is, make the business case wash its face.’ In doing so, it enabled them to oversize a renewable or photovoltaic energy source – the power plant – using that extra power to produce hydrogen and putting that hydrogen to use in the haulage fleet. Re-engineering the haulage fleet gave us the business outcomes we were looking for.

DW: These business cases bring you to temporary barriers. When you hit that temporary barrier, people normally stop, but what we said was, ‘OK, just assume it is not there and go forward.’ That brought the whole business case back again by looking at it differently again.

Anglo’s Smart Energy project is aiming to power a 300-t class truck with hydrogen fuel

IM: Where is this project likely to be situated within the group?

TO: We’re still not 100% fixed as the initial work will be done here (the UK). You are talking about quite specialist skills working with hydrogen.

When the system has gone past its initial testing, it will go to a site, probably in South Africa, but we are not 100% locked into that at this point.

IM: On the 12-month timeline you have given, when would you have to be on site?

TO: The infrastructure will be pre-built here in the UK. We’re effectively testing it here. In a way, the physical truck is the easy bit.

It’s going to be using a 300-t class truck. The guys have already done quite a bit of the detailed measuring and the design elements are well under way.

We’ve also taken the approach to use pre-approved technology, which Donovan can talk about.

DW: This minimises the risk on the first go and allows us to, later, tailor it. For example, if you don’t have a right sized fuel cell currently available off-the-shelf, you just use multiple standard-size fuel cells for now. Then, when you get into the final version you could tailor them into something more specific.

IM: On mechanised cutting, you recently mentioned the building of a “production-sized machine” for at least one of your mines in South Africa. Is this a variant of the Epiroc machine – the Rapid Mine Development System – you have been using at Twickenham?

TO: It’s the next generation of machines. It’s fair to say that, in the last 12 months, the technology has come to the point where we are confident it is viable.

What we’re looking for is a fundamental breakthrough where, for example, we can take the development rates up three or four times from what you would usually expect. That is what we’re chasing. It would involve some sort of pre-conditioning of the rock ahead of the cutting, but the cutting, itself, works.

For us, mechanised cutting is a real solution to some of the safety issues we have had on our plate. Regardless of whether it goes into South Africa or another underground mine, we see it as a key part of our future underground design and operation.

IM: What type of rock pre-conditioning is this likely to be?

TO: I think around the world, people are looking at electricity, microwave, laser, a whole suite of things. None of them have yet quite landed, but they all have potential.

IM: Where does haul truck automation fit into the pipeline for Anglo American?

TO: All the equipment we buy, going forward, will be autonomous-capable, which means we can run it in either format (manned or unmanned). You are then left with a number of decisions – have you got the design to retrofit automation? Is there a safety issue to be considered? Is there a weather issue to contend with? There are a whole series of gates that we’ll take it (automation projects) through.

It’s good to go back to P101 here. Where P100 is getting all of our key processes to world-class benchmarks, P101 is about establishing a new benchmark. By definition, if you get your operations to that point, the gap between that manned performance and autonomous performance is not that great.

Autonomy is part of our future armoury, but when and where and how, we’ll have to wait and see. For example, we are currently looking at the option of autonomous haulage trucks at one of our open-cut mines in Queensland.

When you look at our portfolio of operations, it’s often a more complex environment than when you are just working in the wide open Pilbara.