Tag Archives: Brucutu

Vale evaluating wet tailings processing alternatives at Brucutu iron ore mine

Vale says it is evaluating short-term alternatives to the wet processing of tailings at its Brucutu iron ore mine, in Brazil, as it looks to step up processing activities at the Minas Gerais operation.

The Brucutu plant, which used to dispose of tailings in the Norte/Laranjeiras dam – that has been at “emergency level 1” since December 2, 2019 – is continuing to operate at around 40% of its capacity through wet processing and tailings filtration, Vale noted.

Yet, the miner said it was evaluating “short-term alternatives” for tailings disposal, such as the optimised use of the Sul dam. These options are being tested by geotechnical and operational teams and may increase Brucutu plant’s processing capacity to 80%, Vale noted.

It warned that, if such alternatives for tailings disposal or the reclassification of the emergency level for Norte/Laranjeiras dam are not achieved until the end of the June quarter, there will “likely be an impact on the 2020 annual iron ore fines production volume”.

Vale took the decision to temporarily suspend the disposal of tailings at the Laranjeiras dam, part of the Brucutu iron ore mine, while assessing the dam’s geotechnical characteristics, back in December. During the shutdown, the dam will have the Level 1 emergency protocol adopted, Vale said. At that point, Vale put the suspension period at one-to-two months.

At the same time, the company reiterated its plans to continue to invest in dry stacking technologies to reduce its exposure to wet tailings dams.

Vale halts tailings disposal at Brucutu dam as it outlines dry stacking investments

Vale says it has taken the decision to temporarily suspend the disposal of tailings at the Laranjeiras dam, part of the Brucutu iron ore mine, in Minas Gerais, Brazil, while assessing the dam’s geotechnical characteristics.

During the shutdown, the dam will have the Level 1 emergency protocol adopted, Vale said. This does not require the evacuation of the downstream population, according to the National Mining Agency.

The Laranjeiras dam had its Statement of Condition of Stability issued on September 30, 2019, which remains valid, Vale clarified.

During the suspension period – estimated at 1-2 months – the Brucutu plant will operate with around 40% of its capacity through wet processing with tailings filtration and dry stacking, Vale said. This will reduce output by some 1.5 Mt/mth of iron ore.

The temporary stoppage does not lead to changes in Vale’s iron ore and pellet sales guidance, which remains, in 2019 and in the December quarter, at 307-312 Mt and 83-88 Mt, respectively.

For the March quarter 2020, production and sales are expected to range between 68-73 Mt, due to weather-related seasonality, the gradual and safe return of operations and in line with the margin over volume strategy, it said.

Despite this setback, Vale executives reiterated its ambitious ‘dry processing’ tailings plan at its Vale Day event in New York, yesterday.

The company said, in its Northern System, 81% of iron ore production was already through the dry processing route, while the Minas Gerais division had 32% of production through such means. Vale plans to convert 70% of its output to dry processing by 2023, compared with 60% today.

The company is investing $1.8 billion between 2020 and 2024 to help with this dry stacking aim, with the main sites operating converting to this solution being the Cauê, Conceição and Brucutu operations.

In addition to this, Vale executives said the company plans to produce the world’s first industrial-scale dry magnetic fines concentrate through the dry concentration innovations it acquired with New Steel in 2018. Vale plans to spend $100 million for 1.5 Mt/y of dry product, with start-up planned in 2022, according to the executives.

In addition to this, Vale said it had moved up its renewable energy plans at its operations and now intended to power its Brazil mines by only renewable means by 2025, compared with its previous 2030 goal. It would go global with 100% renewables by 2030, it added.

Vale and Vivo sign 4G/LTE deal to bolster mine site automation

Vale says it has signed an agreement with Vivo (Telefônica Brasil) to implement a private 4G/LTE network at its operations in Brazil.

The network will help the miner optimise its use of autonomous equipment, which requires a wide coverage area and high traffic capacity for a significant amount of data. Almost R$21 million ($5 million) will be invested in this project, Vale said.

This will make Vale and Vivo the first companies to deploy a private LTE network with these characteristics in the country, according to Vale.

From the first half of 2020, the network will be available at Carajás (Pará) mine, where three autonomous drills are already operating and autonomous trucks will be adopted soon. Then, this innovation will be applied at Brucutu mine (pictured), in São Gonçalo do Rio Abaixo (Minas Gerais), where 13 autonomous trucks operate. This network also has the potential to be used to connect dam monitoring instruments, the company said.

Vale said of the network: “It will boost Vale’s autonomous vehicles program, which aims to increase safety by removing employees from the risk area. Autonomous equipment also generates operational efficiency and sustainability gains increasing equipment useful life by almost 15% and reducing fuel consumption and maintenance costs by almost 10%.”

Vivo’s solution was chosen due to its reliability and experience in private LTE networks, Vale said. Safety and the possibility of converging different types of traffic on the same network – such as data, voice, and video – were also considered. At Brucutu mine, for example, the autonomous trucks currently operating on a WiMax network, which will be migrated to the new network in the future.

Gustavo Vieira, Vale’s IT director, said: “In addition to the benefits regarding data volume and coverage, the use of LTE is also an important investment due to it is scalability; all mobile phone technology development must comply with this standard from now on. Fourth generation is already being used; thus, technology upgrades will cost less than those for technologies that are not commonly used.”

Alex Salgado, Vivo B2B vice president, said a private LTE solution meets specific needs of businesses while meeting the requirements of mission-critical applications that demand “high safety, mobility in production lines, free-interference spectrum, and traffic prioritisation, as well as connecting a high volume of IoT devices in an open and widely available ecosystem”.

The partnership will enable Vale to use Vivo’s services in these regions. Vivo will also provide 4G coverage, which will help communication among employees of the mine operations.

In Latin America, this partnership model is only currently available in Chile, which is being tested. Vale also uses private 4G/LTE networks in its operations in Canada and Malaysia, it said.

Autonomous haul trucks coming to Vale’s Carajás iron ore mine

Vale says it is to start trialling autonomous haulage at its Carajás mine in Pará, Brazil, following a successful deployment at its Brucutu iron ore mine in Minas Gerais.

The company plans to run both autonomous and manned trucks at the operation, the world’s largest open-pit iron ore mine, it said.

Completion of the autonomous testing phase is planned to June 2020, when the autonomous vehicles begin to operate. The number of autonomous vehicles will increase year by year and, depending on the test results, may reach 37 in 2024.

This year, the company’s Brucutu iron ore mine began operating exclusively with autonomous haul trucks. Thirteen Caterpillar 240 ton (218 t) 793F CMD fully autonomous trucks, managed using the Cat autonomous haulage system, Command for hauling, part of its MineStar™ suite of technology products, are now running, after the company equipped seven trucks with this technology in 2018.

Combined with a staff development and training plan at Carajás, the autonomous innovation aims to increase the safety of operations, in addition to generating environmental benefits and a competitive edge, Vale said.

Two autonomous trucks are expected to start the testing phase in an isolated area of Carajás mine by the end of November, but training of the operators began in October. In addition to autonomous haulage, three autonomous drills started operating in the mine last year, Vale said.

Vale explained: “In an autonomous operation, trucks are controlled by computer systems, GPS, radar, and artificial intelligence, and monitored by operators in control rooms located miles away from the operations, providing more safety for the activity. When risks are detected, the equipment shuts down until the path is cleared. Sensors of the safety system can detect larger objects, such as large rocks and other trucks, as well as people near the roads.”

Compared with conventional transport, productivity of the autonomous operation system is higher, according to Vale. “Based on the technology market data, Vale expects to increase the useful life of equipment by 15%. Fuel consumption and maintenance costs are also estimated to be reduced by 10%, and the average speed for trucks will increase,” it said.

Autonomous operation also brings important environmental benefits. The reduced consumption of fuel by the machines results in a lower volume of CO2 and particulate matter emissions and less waste, such as parts, tyres and lubricants.

According to Antonio Padovezi, North Corridor Director for Vale, in addition to the safety factor, the use of autonomous equipment in Carajás will ensure greater sustainability for Brazilian mining. “It is another breakthrough with great economic, environmental, and social gains. It reduces employees’ exposure to risks, increases competitiveness, reduces emission of polluting gases and promotes professional training and development, following a natural trend experienced today in the market worldwide,” Padovezi said.

Implementation of the autonomous operation is combined with a staff development plan, which includes creation of a training centre in the city of Parauapebas by the supplying company. The plan is along the lines of Brucutu, where all conventional truck operators will be reassigned to other activities. At Brucutu, part of the team is managing and controlling the autonomous equipment while another part is taking on new “automation-related tasks”. Some employees have been reallocated to other areas.

Vale is deploying a digital transformation program as part of its Industry 4.0 developments.

This has allowed the company to increase productivity, operational efficiency, and safety, in addition to improving its financial performance and driving innovation, the company said.

Technological innovations developed by the company include the Internet of Things, artificial intelligence, mobile applications, robotisation, and autonomous equipment (such as trucks and drills).

The program will also support the strategic pillars presented by Vale this year – improve the company’s operational approach to safety and operational excellence as well as bring a positive impact to society, becoming a development facilitator for the areas in which it operates while promoting a safer and more sustainable industry, Vale said.

Why the Pilbara leads the way in haul truck automation

A presentation at last month’s AusIMM Iron Ore 2019 Conference, in Perth, Western Australia, made it clear that the state’s steel raw material miners are leading the way when it comes to applying autonomous haulage systems (AHS) in open-pit mining.

Richard Price, Manager of Projects for Mining Technicians Group Australia (MTGA), has been involved in this technology space for a number of years, having initially witnessed an automation trial involving two trucks at Alcoa’s Willowdale bauxite mine, in Pinjarra, all the way back in 1994.

At the conference, his paper set out the state of play in Pilbara when it comes to AHS, explaining: the first commercial scale trial in iron ore took place at Rio Tinto’s West Angelas operation in 2008, there are two original equipment manufacturer (OEM) AHS operating in the Pilbara – Caterpillar Command for Hauling and the Komatsu FrontRunner – and the three major iron ore miners (Rio Tinto, BHP and Fortescue Metals Group (FMG)) were leaders when it comes to using autonomous trucks.

FMG is the largest operator of autonomous trucks in the Pilbara – making it effectively the largest in the world – with 128 at the end of June (according to the miner’s June quarter results). Rio, meanwhile, had 96 up and running, with BHP having a total of 50, as per publicly released data.

“FMG has plans to automate all of their trucks, including the first non-OEM trucks on an alternate OEM system,” Price said, with him adding that the company has now automated a number of Komatsu 930E vehicles using the Caterpillar Command for Hauling AHS: a world first.

“Additionally, FMG is also operating multiple Caterpillar OEM trucks onsite, in another world first having three classes of truck on the one system at the same site (789D, 793F and 930E),” he said.

While Komatsu, historically, has more time in the field with commercial autonomous applications – it surpassed 2 billion tons of autonomous haulage in November – than Caterpillar, the Illinois-based OEM has received more global success, being able to point to AHS deployments in the oil sands of Canada, the coal mines of British Columbia and Vale’s iron ore operations in Brazil.

“With regards to the on-board AHS componentry, the Komatsu system is somewhat simpler than the Caterpillar system,” Price said. “The significant difference is that Caterpillar utilises a LiDAR (Velodyne 64-layer), with RADAR, whilst the Komatsu system uses RADAR only. However there are additional differences in the on-board controls – the Caterpillar system is known for having more significant vehicle on-board computing power, versus the Komatsu system which places greater reliance on the wireless network whilst performing most of the calculations on the server side.”

Even with the on-board computing power of Caterpillar’s system, the performance of these trucks only tends to be as good as the communications infrastructure they are tied to.

Presently, only the Komatsu system has announced successful trials of using 4G Long Term Evolution (LTE) network technology as the communications system which commands the trucks, with the Caterpillar system presently reliant on wireless networking technology, “of which all current implementations rely upon (globally)”, Price said.

One of the issues with such technologies is the trucks stop driving, or operating, if they lose communications, with the trucks communicating, via this network, their position to each other and directional heading and speed.

The way the trucks re-start their driving routine is, at present, via manual visual inspection, which can be a process that takes time.

And, according to Price, a significant problematic issue with trucks stopping driving across all the Pilbara sites is the triggering of a false positive object detection.

“These are often referred to as ‘ODs’ on the various sites which utilise AHS,” Price said, with many operators blaming undulations in the road, pot holes, or small rocks for these occurrences.

Again, manual inspection is normally required as part of an operation’s procedure for re-starting the autonomous trucks.

Out in front

Despite these communication and OD problems, Western Australia still leads the way when it comes to automation with the Pilbara hosting around 75% of the circa-370 trucks operating globally.
What is the reason for this? Price highlighted five bullet points in his speech:

  • High cost of operators – annual salaries for truck operations are, in general, over A$100,000 ($68,882);
  • Ease of implementation – “the Pilbara miners generally have open ground, and have had an opportunity to trial the technology in a dedicated work area prior to a site-wide implementation,” Price said, adding that the topography has also made it simpler to install the required communications systems;
  • Scale and longevity of operations – Previously cost-benefit analysis of AHS included an approximate cutoff point of 12 Mt/y total material movement, which equates to six to eight off-highway haul trucks, Price said. All operations exceed this, as well as having long mine lives;
  • The fact that all the sites which have presently deployed AHS are currently fly-in/fly-out mines which transport the staff to site from their point-of-hire, and;
  • Experience of technology and processes in the Pilbara – miners in the region have long-term familiarity with fleet management systems and technology adoption.

Price said: “Western Australia does not necessarily have any unique or special advantage, however, it has made sense for Pilbara iron ore operators to implement AHS for the reasons outlined above.”

The benefits

MTGA’s Price pointed to several quotes from the mining companies themselves to explain the benefits of automation.

Rio Tinto, in 2018, said: “On average, each autonomous truck was estimated to have operated about 700 hours more than conventional haul trucks during 2017 and around 15% lower load and haul unit costs.”

FMG, in the same year, said it was seeing 32% productivity improvements with autonomous trucking.

Vale, meanwhile, previously told Mining.com: “The adoption of autonomous trucks at Brucutu (iron ore mine, in Brazil) is expected to reduce fuel consumption by more than 10%. Maintenance costs, in turn, should fall by another 10% and off-road truck tyres, which cost up to $40,000, are expected to have 25% lower wear. The overall gains translate into a 15% increase in equipment life, reducing investments in new acquisitions and reducing carbon dioxide emissions at the same time.”

Price said: “There are clearly differing metrics being monitored by these three operators at present. However, irrespective of the metrics monitored, AHS obviously has had a significant impact on the operating environment.

“It appears that the increase in utilisation of the autonomous trucks is the most significant benefit that they provide. The decrease in costs is also helpful, but the increase in predictability of the truck fleet is what drives the actual benefit.

“A number of materially measurable but difficult to quantify benefits exist from the rendering of trucks autonomous as well. These include less maintenance, better tyre wear (or increased tyre life), reduced fuel costs (for the same tonnage output) and better overall truck performance.”

For instance, Komatsu has previously said the optimised automatic controls of AHS reduce sudden acceleration and abrupt steering, resulting in a 40% improvement in tyre life compared with conventional operations.

And, of course, there are the numerous safety benefits that come with using automated haul trucks.

The future

While Price believes that mining will continue to become more autonomous, he said the mine of the future was likely to involve the automatic distribution of data files that trucks would work off without human involvement.

“For now, technologies such as LTE for better communications network coverage, the use of drones, long-range cameras or other autonomous ground vehicles to conduct the manual visual inspection and other autonomous equipment will be implemented,” he said.

He added: “It is likely that there will be a continuum of development over the next 20-30 years.

“Mining companies and OEMs will have a lot to learn from automotive vehicle automation. Obviously, there are more cars on the roads than there are off-highway haulage trucks on minesites. Therefore the general costs of automation kits will come down, and there will be an opportunity to conduct operations in a GPS-denied environment.

“Already, the costs of select items such as the LiDAR utilised by the Caterpillar system have halved in price since they were used a decade ago. Solid state LiDARs, as opposed to rotational, are being implemented in the automotive industry already.”

He pointed to MINExpo 2016, in Las Vegas, when Komatsu showcased its cabless, driverless truck as one development to look out for.

“It is predicted that in the longer-term future (ie 20-30 years’ time), cabs will be an additional and expensive option to add onto an off-highway heavy haulage truck,” he said.

“Whilst the future is autonomous, it will be technologically more advanced than the present technologies,” he concluded, adding that, given its head start, one would expect the Pilbara iron ore industry to deploy these technologies first.

MTGA’s Richard Price has also written a business case study on AHS, published by AusIMM – www.ausimmbulletin.com/feature/autonomous-haulage-systems-the-business-case/ – and, in partnership with Whittle Consulting’s Nick Redwood, put together an Autonomous Haulage Systems Financial Model Assessment – www.whittleconsulting.com.au/wp-content/uploads/2017/10/Autonomous-Haulage-Study-Report-Rev-F.pdf

New court order could lead to shutdown of Vale’s Brucutu iron ore mine

Vale says it has been made aware of a decision by the 22nd Civil Court of the Comarca of Belo Horizonte, Brazil, ordering the iron ore miner to stop using its Laranjeiras, Menezes II, Capitão do Mato, Dique B, Taquaras, Forquilha I, Forquilha II and Forquilha III dams.

The decision, which is within the scope of the public civil action no 5013909-51.2019.8.13.0024 filed by the Public Prosecution Office of the State of Minas Gerais, could see the company have to close the Brucutu mine (pictured) in its Minas Centrais complex, cutting some 30 Mt/y of iron ore supply.

The Brucutu unit is the largest iron mine of Minas Gerais in production, and the second largest in the country, only behind Carajás, in Pará, according to the company.

Among the dams included in the court order, three were built by the upstream method – Forquilha I, Forquilha II and Forquilha III – and were already inactive and covered by the accelerated decommissioning plan Vale previously announced to the market. The other structures, including the Laranjeiras dam at Brucutu, were built by the conventional method.

“These structures built by the conventional method have the sole purpose of sediment containment and not tailings disposal except in the case of the Laranjeiras dam,” Vale said. “All dams are duly licensed and have their respective stability reports in force. Vale therefore understands that there is no technical basis nor risk assessment to justify a decision to suspend the operation of any of these dams.”

Vale said it will adopt the “appropriate legal measures” in relation to this decision and reiterated that all the emergency measures necessary to assist the impacted people and to mitigate the impacts resulting from the breach of Dam I of the Córrego de Feijão mine are being duly adopted.

Vale currently has a fleet of Caterpillar 240 ton (218 t) 793F CMD fully autonomous trucks running at the Brucutu iron ore mine.