Tag Archives: tailings

Australia miners pool expertise to improve tailings management

Environmental, Mineral processing, Mining industry recognition, Mining services, Sustainable mining, Water management, , ,

Australia’s minerals industry is looking to confront the tailings management issues that have plagued the global industry in recent years with the release of the Australian Mining Tailings Communique.

The Minerals Council of Australia (MCA) will support the communique, developed by MCA member companies after a workshop earlier this year, with a program of training, research and governance actions currently in development, it said.

Opportunities will be identified to build industry expertise and enhance technical capacity on tailings management for the minerals workforce, the MCA added.

“Tragic incidents around the world over the past decade reinforce the need for ongoing vigilance, review and change and raise legitimate questions about tailings management practices from governments, investors and the community,” the council said.

Australia’s minerals industry met earlier this year to review governance, culture and risk management for tailings storage facility management.

While the MCA said current tailings management practices in Australia are “highly regulated and at the forefront of global best practice”, it said the industry is committed to continual improvement as part of its culture of safe and responsible resource development.

This saw the companies, develop a list of actions to take on. This included:

  • Communicate and engage – communicate and engage with the community including government and other key stakeholders on our approach to tailings management in a transparent manner to build community confidence;
  • Leadership, governance and systems – assess and identify key elements of corporate leadership, culture, systems and governance to proactively manage tailings risks and share information;
  • Share leading practice – continue to actively share and promote industry leading practice and lessons learned in Australia and overseas from all industries;
  • Build industry expertise – identify opportunities to enhance industry capacity in key technical aspects of tailings management; and
  • Engage internationally – offer Australian expertise to help build global initiatives on tailings management including the development of, and alignment to, standards and guidelines.

The MCA says it will develop a program of work to reflect the above actions by the end of 2019.

“There is no room for complacency and honest and transparent communication and engagement with the workforce, host communities, governments, investors and other stakeholders is central to the industry’s approach,” it said.

Tenova TAKRAF proves dry stack tailings credentials at Uzbekistan gold mine

Bulk handling, Environmental, Mine operation news, Mining equipment, Precious metals, Sustainable mining, Water management, , , , , , , ,

Tenova TAKRAF says it recently installed three DELKOR overhead filter presses at a gold mine’s processing plant in Uzbekistan as part of its wider tailings dewatering system.

The system comprises three DELKOR overhead filter presses each processing around 120 m3/h of gold tailings. Each machine contains 177 mixed membrane filter plates with a size of 2 m x 2 m, and includes a high-pressure cloth washing system.

These filter presses form an important part of Tenova TAKRAF’s complete Dry Stack Tailings (DST) technologies solution, which covers processes from sedimentation to filtration and material handling, the company said.

The supply also included several pieces of ancillary equipment, including belt conveyors for cakes discharged from the filter press (each machine is equipped with a cake breaker), pumping skids for membrane inflation, filter cake washing pumps and high-pressure cloth washing pumps.

“The entire scope of supply, including the slurry feed pumps, is fully controlled and managed by state-of-the-art software,” the company said.

It added: “The complexity of the dewatering process required by this project clearly highlights DELKOR’s filter press potential across the dewatering spectrum. In fact, the filter press cycle includes filter cake squeezing, filter cake washing and filter cake air blowing, with the filter cakes washed with process water in order to remove unwanted residual cyanides from the dewatered cakes.

“Importantly, the required residual moisture content within the dewatered cakes was achieved immediately during start-up.”

Marco Zeni, Tenova DELKOR Project Manager, said: “Notwithstanding demanding site conditions, installation and commissioning, together with the required operational training, was successfully completed. With this project, we take another important step towards firmly establishing DELKOR also as a provider of filter presses to round up the filtration product portfolio and once again demonstrating that: it pays to talk to a specialist.”

FLSmidth notes sustainability and digital mining developments in Q2 results

Automation, Bulk handling, Comminution of minerals, Environmental, IoT, Mineral processing, Mining consumables, Mining equipment, Mining finance, Mining services, Mining software, Sustainable mining, Water management, , , , , , ,

FLSmidth’s June quarter saw an improvement in revenue and profitability as the company’s Mining and Cement divisions continued to perform strongly.

The company’s order intake for the June quarter amounted to DKK5 billion ($752 million), down 2% from the same period a year ago. Mining order intake, specifically, declined 7%, mainly due to a lower capital order intake, the company said. This included an order of around DKK375 million from Rio Tinto for its Koodaideri iron ore project.

During the quarter, the company also completed the acquisition of IMP Automation.

FLSmidth’s order backlog stood at DKK16.8 billion by the end of June, up 16% from the same time last year.

Revenue increased 16% year-on-year in the quarter to DKK5.5 billion on high activity level, while earnings before interest taxes and amortisation came in at DKK487 million, up 28% year-on-year.

FLSmidth Group CEO, Thomas Schulz, said: “The second (June) quarter showed a strong performance with improved revenue and profitability, driven by both Mining and Cement. Following a slow start to the year, we have been successful at converting backlog to revenue in the second quarter. In close cooperation with our customers, we have continued to deliver on our vision to provide sustainable productivity enhancement.”

Schulz continued: “Our success with both service and capital orders, demonstrates our customers’ confidence in our ability to enhance their productivity. This is supported by an increased push for sustainable solutions that ties in well with our position, capabilities and track record.”

In the company’s Mining division, Schulz said the company saw increased interest for new technologies such as dry stack tailings, but also a general need to reduce water consumption in the production process. The company said the mining market remained robust.

The company added on the mining market: “Equipment demand continues to evolve around replacement and brownfield projects, with select greenfield opportunities. Miners are attentive of rising global issues and remain cautious on large and high-risk investments. The long-term pipeline for larger projects is encouraging, but most projects are currently not reaching further than the engineering/prefeasibility stage.”

It continued: “Customers across regions and commodities are increasingly demanding digitalised solutions to improve performance, reduce operating costs and maximise safety in operations. Similarly, customers show increased interest in technology to obtain a more sustainable production, not least our effective solutions for tailings management given the latest issues with tailings dams failures and the related environmental impact.”

Coringa dry stacking plan finds favour with state environmental agency, Serabi says

Environmental, Mineral exploration, Mineral project development, Mining project news, Mining safety, Precious metals, Sustainable mining, Water management, , , , , , , ,

With Serabi Gold having supplied all required data for a preliminary economic assessment (PEA) on its Coringa gold project, in Brazil, to its independent consultants Global Resource Engineering Limited, CEO Mike Hodgson says the London- and Toronto-listed firm is now working hard on the permitting side.

Permitting a mine in Brazil – in particular the waste storage element – has become a lot trickier in the past few years following two major tailings dam collapses at iron ore mines in the country.

But, in the company’s June quarter results, Hodgson said Serabi was making good progress on permitting Coringa, a deposit that comes with 216,000 oz of indicated resources at an average in-situ grade of 7.95 g/t Au and inferred resources of 298,000 oz at 6.46 g/t.

He said: “The plan to replace a conventional tailings dam with installing a filtration plant allowing for the dry stacking of tails has been well received by the state environmental agency, SEMAS, who had already approved the original environmental impact assessment (EIA) on the basis of a conventional dam.”

The company is now completing an amendment to the EIA to reflect this design variation, he said, explaining that Serabi expects SEMAS to approve the amendment and, then, proceed with the necessary public hearings.

“We hope to be in a position to receive the Preliminary Licence during the second half of the year,” he said.

Coringa is located in north-central Brazil, in Pará State, 70 km southeast of the city of Novo Progresso.

Artisanal mining at Coringa produced an estimated 10 t of gold (322,600 oz) from alluvial and primary sources within the deep saprolite or oxidised parts of shear zones being mined using high-pressure water hoses or hand-cobbing to depths of 15 m, according to Serabi. Other than the artisanal workings, no other production has occurred at Coringa.

Serabi acquired Coringa from Anfield Mining on December 21, 2017, with management considering the asset to be very much a “carbon-copy” of Palito in terms of the geology, size and mining operations that will be used. The company’s Palito complex is made up of high grade, narrow vein underground mines that produce around 40,000 oz/y of gold.

The PEA on Coringa is still expected to be completed by the end of July, Serabi said.

Weir Minerals’s Essack on end-to-end tailings and pipeline solutions

Bulk handling, Comminution of minerals, Environmental, Mineral processing, Mining equipment, Mining services, Sustainable mining, Water management, , , , , , ,

As mining companies’ tailings facilities continue to be scrutinised by regulators and non-governmental organisations, Weir Minerals Africa Process Manager, Hoosen Essack, has talked up the need for tailored tailings solutions for the future.

Combined with the stringent accountability that mine operators have to local communities, tailings management is now a significant consideration, with processing requirements and technology changing rapidly. Traditionally involved in the pumping of tailings, at Weir Minerals we have extended our expertise into this area to encompass the entire tailings process. From dewatering to transport, disposal, and the conversion of tailings into a resource, we can provide customers with an end-to-end tailings and pipeline solution.

This holistic, solutions-based approach to tailings management strengthens our relationship with customers and adds value to their operation beyond pumping. In light of water conservation, operational sustainability and safe deposition of tailings, it’s important that we invest in this area to help solve crucial issues within the mining sector.

Our extension into the tailings processing field means we are now involved in the production of the material, as opposed to simply transporting it. Through extensive consultation, site visits and audits, our team ascertains the customer’s objectives and recommends a complete, optimal solution to meet their needs, which can include dewatering equipment, piping, pumps, valves and instrumentation.

This seamless approach is a departure from the traditional industry practice of sourcing components from multiple suppliers, which are challenging to integrate. Our extensive research and development capabilities means we can provide a wide spectrum of tailings management options not limited by a particular type of technology or equipment.

This involves assessing the variations in capital and operating expenditure along with the overall and long-term benefits of each, providing a truly customised solution. Prior to implementation, rigorous testing and trials are conducted to assess viability and performance ahead of final selection, detailed design and engineering, delivery and commissioning. Another key benefit to customers is the ability to transform tailings into products, which can safely be used by the mine, such as road construction material. This involves dewatering of tailings, in which we have extensive expertise.

Dewatering involves removing liquid from waste slurry so that the remaining solids can be deposited in a tailings storage facility or returned to the site from which it was mined as backfill. There are several dewatering methods to render waste slurry to differing degrees of dryness, ready for transport from the plant to the deposition site. Any liquid recovered through dewatering is returned for reuse in the process.

We can provide a variety of processing systems inclusive of equipment and infrastructure to achieve the final tailings product that is required by the customer, from thickening to create a paste, or applying a filter to produce a product which can be dry deposited. As tailings management evolves, the industry is moving towards the latter for increased safety and stability, and in the process maximising water recovery.

As mine operators become more vigilant in managing their tailings, new processing technology is continually developed, including at the Weir Technical Centre in Australia. Innovative, uniquely tailored solutions incorporating high performance equipment and a global service footprint means we are leading the industry in making tailings more sustainable. Ideally, this will lead to a future where tailings related hazards are a thing of the past.

Zest WEG companies supply DRDGOLD with electrics for Far West Gold Recoveries project

Mine operation news, Mining equipment, Mining services, Power supply for mines, Precious metals, , , , , , , , ,

WEG Automation Africa and WEG Transformers Africa, part of the Zest WEG Group, have assisted with the commissioning of a containerised substation and control room solution at DRDGOLD’s new Far West Gold Recoveries project’s Phase 1 tailings site, in South Africa.

The gold tailings recovery project will see 500,000 t/mth of material pumped from the Driefontein 5 dam through a new 2 km pipeline to the Driefontein 2 plant.

Business Development Manager for Projects and Contracts at WEG Automation Africa, Tyrone Willemse, said the development of Phase 1 began in August 2018, with first commissioning beginning just four months later, in December 2018.

In an unusual step for such a project, the electrical portion was supplied ahead to the mechanical aspects to expedite the contract, according to Willemse.

“At the tailings facility, the customer required a medium voltage substation, a low voltage substation and a control room,” Willemse said. “This was accommodated within a double-container structure, which also included a room to house all the free-standing variable speed drives (VSDs) and uninterruptible power supplies (UPSs).”

The container was mounted on a concrete plinth with 2.5 m pillars elevating the structure to allow optimal visibility from the control room, according to the company. Heat losses were factored into the design to ensure the substation remained cool and the installation was fitted with a fire detection system.

Willemse said an important consideration was to reduce the footprint of the substation, with free-standing VSDs allowing this.

“Had the VDS configuration been a conventional design, these units would have been incorporated in panels and we would have needed an additional container,” he said. The VSDs are placed against the container wall and are completely isolated from any exposed conductors.

Motor Control Centres (MMC) were also provided for the modifications to the Driefontein 2 plant. The MCC for the thickener is fed by two 1,600 kVA transformers and the tailings MCC is fed by one 1,600 kVA transformer; both were manufactured at WEG Transformers Africa’s Wadeville facility.

Stuart Brown, Sales Team Leader at WEG Transformers Africa, said: “For this project, the transformers are designed to incorporate the VSD component of the load, and this demonstrates the engineering flexibility that WEG Transformers Africa can offer customers in meeting specific operating parameters. It is not a distribution transformer as such, but rather a VSD-type transformer.”

Cooling capacity had to be increased to accommodate the harmonics, and flux density is also reduced. The WEG transformers are built to SANS 780 specification, which stipulates losses even lower than the global IEC standard, according to the company. This will translate, over time, into energy savings for the customer, and is an important advantage, according to Brown.

Fabrication of all MCCs and the adaptations to the container were undertaken by WEG Automation Africa at its facilities in Robertsham, Johannesburg, and Heidelberg, further adding to the high local content on this project. This local manufacturing capability is a part of Zest WEG Group’s status as a B-BBEE Level 1 contributor.

Particular care was taken with on-site modifications at the plant itself. At the milling and classification MCC extension, WEG Automation Africa was required to connect to DRDGOLD’s existing MCCs. “The use of joggle chambers on either side of the existing board made for best practice and greater safety,” the company said. “On the return water MCC, a raised plinth was added for easier cable access. Top entry cables for the slurry receiving and tailings MCC was facilitated by innovative board design.”

The MCCs incorporate an extensive range of WEG LV products including WEG air circuit breakers to facilitate a 50 kA fault level, WEG moulded case circuit breakers, WEG contactors, WEG fast-acting high rapid fuses, and WEG motor protection relays.

WEG W22 LV electric motors were selected to drive the tailings facility pumps, ensuring lower energy consumption through the design of these units, which have an optimal cooling fin design, the company said. Ingress protection is to IP66 ensuring effective sealing against liquid and dust.

WEG Automation Africa, formerly known as Shaw Controls, recently changed its name to align with parent company, Brazil-based WEG’s global strategy. Its local manufacturing operation has been the recipient of an extensive investment programme by WEG that has seen its facilities upgraded as part of the ongoing commitment to the South African economy and customers in the region.

Metso commits to a filtered tailings future

Bulk handling, Comminution of minerals, Environmental, Mineral processing, Mining equipment, Mining industry recognition, Mining services, Sustainable mining, Water management, , , , , , , , , , , , ,

Metso might have just launched a new tailings management concept, but the management of tailings and dewatering solutions are nothing new for the mineral processing company.

Helsinki-headquartered Metso developed its first VPA filter for mining in the 1980s – the maiden unit being delivered to the Greens Creek mine in Alaska (now owned by Hecla Mining) – and has since dispatched hundreds of units to mines across the globe.

In addition, Metso has a long history of designing and manufacturing tube presses and other complementary dewatering solutions; its current membrane-type filter press offers pressures up to 100 bar for particularly difficult dewatering applications, such as china clay, while its inclined plate settler (IPS) and dewatering spirals offer separation and thickening options for miners.

The VPX™ filter is the launch product that comes with this new tailings management concept, but there is much more to this focus than a lone invention.

As Niclas Hällevall, VP, Process Equipment for Metso, told IM: “It is no longer a matter of just finding the most technically-suitable equipment or solutions to do the job. It is about how to transform mining into a sustainable and long-term development.”

Metso is intent on “challenging the conventional” in this regard. This includes looking at its own approach to designing mineral processing equipment – ensuring all products use, recycle and recover water in a responsible manner – as well as the industry’s way of thinking. Instead of pursuing short-term fixes, such as implementing tailings monitoring solutions using sensors, the company thinks miners should prepare for a future where wet tailings dams are eradicated from mine sites. Dry stacking – or filtering – tailings is the end goal Metso is pursuing.

This unconventional mindset is also apparent in the design of Metso’s VPX filter. Instead of equipping the machine for high throughputs alone, Metso has built the filter to manage varied input materials and to offer pressures up to 25 bars (and perhaps even higher pressures).

Metso has eliminated the use of hydraulics on this new filter, instead using electromechanical screws to achieve the high-pressure closing that turns wet material into dried cakes with as low as 7% moisture content in some applications. This electromechanical switch could cut operating costs due to a reduction in maintenance requirements, according to the company. The modular design, meanwhile, allows the filter to be scaled to any size, plus fit it into a container for easy logistics.

An advanced control system (ACS) using self-learning functions provide customers with a solution to monitor the operation of the filter, while there are plans to equip the machine with artificial intelligence functionality to monitor the conditions of the input material and select the optimal dewatering route.

Also, the filter press offers a variable and very fast opening and closing time thanks to the robust rack and pinion system, thus providing the high-capacity dewatering large mines require.

Metso is ready with its “future-ready” solution – a pilot VPX filter is currently in Sala, Sweden, about to be taken on a roadshow. This unit has already been tested on a mine tailings application in Sweden, IM understands, with the company expecting many more trials over the next year.

As Lars Gustavsson, Business Manager, Beneficiation Solutions, explained, the company’s filter press trial plan includes taking small size samples in its laboratory before graduating to the full-scale pilot unit, which is equipped with the same ACS and sensors commercial units will have. “This gives customers all they need to build the business case,” he said.

The Metso tailings management concept goes further: Hällevall says the use of the Metso IPS and Metso MHC™ hydrocyclone, in circuit with a VPX filter, results in less use of chemicals and energy in the dewatering process, on top of water recoveries of up to 90% in some applications. This is achieved by controlling the feed and optimising the filtration process. “We simply separate the stream into fine and coarse streams by using Metso MHC hydrocyclones,” Hällevall says, explaining that the overflow – the fines stream – is directed to the Metso IPS thickener, with the coarse stream going direct to the filter.

With two separate streams, the company can decide the optimum way to filter and dewater the material, with the IPC, in particular, offering the most “superior setting of fines using minimum amounts of flocculants and energy”, Hällevall says.

This new concept has allowed Metso to become one of only a few mining OEMs talking up the use of pressure filters – and accompanying separation and thickening infrastructure – to reprocess legacy tailings dams. The ability to “turn waste into value” could enable mining companies to not only clean up these dams, decrease their footprint and improve their sustainability credentials with local and other stakeholders, it could also allow them to generate additional revenue from the recovery of valuable minerals and metals.

This could potentially provide the positive investment case miners need to start making wet tailings dams a thing of the past.

Just 5% of all fresh tailings generated in 2018 were dewatered in some way, according to Metso’s data. With its own “future-ready” solution now in place, the company is doing its bit for industry to ensure this figure continues to rise.

Metso launches VPX filter as part of new tailings management approach

Environmental, Mining equipment, Sustainable mining, Water management, , , , , , ,

Metso says its new approach to tailings management is aimed at addressing the water conservation and responsible mine reclamation requirements that are becoming increasingly important for mines to ensure they can retain their social license to operate.

Its new approach is spearheaded by the launch of the new Metso VPX™ filter for tailings dewatering, which, with an operating pressure of up to 25 bars, can deal with difficult-to-dewater tailings.

The company’s broader tailings management concept is geared towards enabling and supporting environmentally and economically sustainable mining, it said.

Victor Tapia, President, Mining Equipment business area at Metso, said: “Our ambition is to challenge the conventional way of looking at tailings management in mining.

“In practice, this means that besides environmental and regulatory concerns related to tailings, we need to improve the conservation of water, chemicals and ore, as well as looking for opportunities to reprocess tailings and generate value by extracting any remaining minerals. Ultimately, it allows transforming legacy practices in tailings management into a new, positive value creation model.”

Metso is driving this change by introducing a new concept for the dewatering, handling and reprocessing of tailings. It said: “Designed to maximise water recovery and reduce the footprint of tailings dams or eliminate them completely, Metso Tailings Management Solutions provide a long-term solution for mining companies looking for a viable approach to their tailings management and end-of-mine strategies.”

There are a huge amount of tailings discharged and lying in legacy dams, according to Metso. “Today, only about 5% of tailings are dewatered, while roughly 70% of the mines are located in countries where water scarcity is considered as an issue. The way tailings are handled can have a long-term impact on the mines’ economic efficiency as well as on the well-being of the surrounding environment and communities,” the company said.

Niclas Hällevall, VP of Beneficiation Solutions, Mining Equipment business area, said: “Metso views dry filtered tailings as the most viable and long-term solution for tailings management: it helps in recycling significantly more water to the concentrator, while enabling mines to reduce their freshwater footprint when compared to traditional tailings impoundments. Furthermore, the risk of tailings dam failure could be completely avoided by dewatering and dry stacking the tailings.”

He added: “Contrary to conventional belief, dry tailings are also much more capex (capital expenses) and opex (operating expenses) efficient compared to wet or thickened tailings.”

Metso Tailings Management Solutions bundle Metso’s beneficiation technologies into a “full, customisable and future-ready suite of solutions”, it says. Metso, with its core component, is taking filtration technology “to the next level” by introducing the Metso VPX filter, a new generation filtration solution for maximum water recovery and reuse, it said.

The company said: “The Metso VPX filter can handle difficult-to-dewater tailings, because it has up to 25 bars operating pressure, the highest pressure in its category. This enables up to 90% water recovery. The Metso VPX is also equipped with a fully electromechanical drive system and no hydraulics, making it the safest solution on the market. With its modular design, the Metso VPX filter is scalable as well as easily transportable to the site in standard containers.”

The VPX filter is available for mining customers globally and an ideal solution for a range of dewatering applications, Metso said, adding that the filter press will be on show at the Exposibram trade fair to be held in Brazil, in September.

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

Automation, Base metals, Bulk handling, Coal technology, Comminution of minerals, Environmental, Explosives and blasting, IoT, Mineral processing, Mineral project development, Mining equipment, Mining industry recognition, Mining people, Mining policy, Mining safety, Mining services, Mining software, Mining techniques, Steel and iron ore, Sustainable mining, Water management, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

“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.

BHP establishes task force to handle tailings dams

Environmental, Mining industry recognition, Mining maintenance, Sustainable mining, Water management, , , ,

BHP says it is establishing a dedicated Tailings Task Force to drive enhanced focus on internal dam management plus support the development of international best practice.

The announcement came during an environmental, social and governance briefing where the company also revealed it is “progressing the investigation of new technologies to further mitigate current dam risks and eliminate future risk”.

BHP has interests in 67 operated tailings facilities across all its sites. Of these, 13 operated facilities are active, (12 in Australia, one in Chile), 29 are operated upstream facilities (five of which are active). In addition, its non-operated joint ventures have nine facilities, five of which are upstream, of which all are inactive.

Back in 2016, the company carried out a Dam Risk Review, which identified no immediate concerns regarding dam integrity. This was undertaken to assess the management of tailings facilities following the failure of the Fundão dam at Samarco (a joint venture with Vale).

BHP has since undertaken Dam Safety Reviews which provide assurance statements on dam integrity, the company said.

The company said on the appointment of the task force: “Prior to Brumadinho we already had a significant focus on looking at how we could deliver a step change reduction in tailingsrisk. Brumadinho however has further strengthened our resolve.”

The new Tailings Task Force will be accountable for further enhancing the company’s focus on tailings including the continued improvement and assurance for BHP’s operated tailings storage facilities, the company said. It will also progress its technology efforts and ongoing participation in the setting of new international tailings management standards.

On the latter, BHP said it continued to work with the International Council on Mining and Metals its peers to “drive a step change in tailings management across the sector”.