Comminution & Material Handling
Optimization of production processes is key to reach sustainability targets
It is hard to overstate the importance of comminution – the blasting, grinding and crushing of ore – to the mining value chain. Brownfield investments have dominated Chilean mining development in recent years, as companies invest heavily to increase output, access deeper and lower-grade reserves, and optimize their production processes to take advantage of high copper prices.
In 2020, the merger between Finnish giants Metso and Outotec created one of the leading mining suppliers in the world, with solutions across the entire mineral processing line. Eduardo Nilo, Metso Outotec’s president – South America, revealed that the company has seen growth of 15% to 20% business volume in the region, despite challenges such as Covid, supply chain delays and the Ukrainian situation, and that the consolidation period is now complete.
In October 2021, Metso Outotec won a major in-pit crush and convey solutions (IPCC) order from Codelco’s Radomiro Tomic Óxidos project. Nilo explained that Codelco seeks to give continuity to the open-pit mining operation at Radomiro Tomic for the exploitation of its sulfide and oxide reserves, operating its SX/EW leaching plant until 2030.
To keep the mine operating in oxide extraction during this decade pending the completion of the sulfide project, it is necessary to access reserves that are below or near the current facilities. “This is where Metso Outotec will play a crucial role, supplying Codelco with an EPS (Engineering, Procurement and Services) project that includes the installation of an 11,000 t/h semi-mobile crushing station with a state-of-the-art rotary primary crusher, a Superior MK III 60110, next to the pit mine, which is in production.”
“Weir has developed and improved a technology called High Pressure Grinding Rolls (HPGR), which reduces or eliminates the use of big sag mills, resulting in a much more efficient process and saving approximately 40% energy in rock comminution.”
Ricardo Garib, President, Weir Minerals
Providing further details, Nilo revealed that the solution includes, in addition to engineering and the crusher, an Apron Feeder discharge, an intermediate transfer belt, electrical rooms, dust suppression systems, field assistance service and the extension of the overland sulfide belt by 530 m. He added: “It is also important to highlight that the crushing station is part of Metso Outotec's Planet Positive sustainable solutions, since its operation will mean a reduction of more than 30% in CO2 emissions at the project.”
The level of emission reduction achieved by Metso Outotec’s IPCC solutions at Radomiro Tomic is a pertinent point. Comminution is the most energy intensive process in mining, accounting for approximately half of the energy used in the mining sector according to the Coalition for Energy Efficient Comminution, and 4% of the world’s total electrical energy consumption. It is therefore an area where companies can make one of the most tangible differences to their sustainability goals.
Another of the major global players in the comminution and material handling space is Weir Minerals, whose president, Ricardo Garib, underlined the importance of sustainability and ESG in the mining sector, particularly under the new environmentally-focused Chilean administration. He gave examples of how Weir can help mining companies optimize their operations: “Weir has developed and improved a technology called High Pressure Grinding Rolls (HPGR), which reduces or eliminates the use of big sag mills, resulting in a much more efficient process and saving approximately 40% energy in rock comminution.”
Garib went on to mention how the role of mining suppliers has evolved in the last three years to become more of a partnership than before, given the scarcity of labor and tools as well as supply chain disruptions. “Miners understand that they cannot do everything themselves and thus need to partner with complementary companies,” he said.
Suppliers are also forming business partnerships, such as Weir has with ANDRITZ for tailings solutions, or M&A transactions to bolster certain areas of the business.
In 2021, the Weir Group acquired Canadian mining technology firm, Motion Metrics, through Weir’s ESCO division, to serve as the company’s global center of excellence for AI and Machine Vision technology. Shahram Tafazoli, chief of AI at Weir Motion Metrics and founder of Motion Metrics, discussed how, over the years, the company has developed technologies for fragmentation analysis to monitor particle size distribution (PSD): “Our value proposition is to optimize comminution through AI by putting AI enabled 2D and 3D ‘eyes’ into the process so that we can sense rock sizes in various stages of mining. High quality accurate data is sent to our secure cloud platform from where the information can be used to make recommendations for the mining process,” explained Tafazoli, adding that this fragmentation monitoring solution allows for optimized production through selective mining, whilst reducing energy consumption and freshwater usage.
“Mining equipment is more valuable if it can respond to the needs of each client: they all have specific brands of components, as well as electric, structural and mechanical requirements, and each client has their own experience of how equipment responds to their maintenance and operational processes.”
Andrés Osorio, General Manager, Sistemas de Transporte de Materiales (STM)
During interviews with many of the companies involved in the comminution and material handling space in Chile, one of the common trends has been the importance of tailoring solutions to the needs of the client and the mine environment rather than offering a standardized solution.
José Pablo Domínguez, general manager South America of ME Elecmetal, spoke of the company’s work at INCO and QB2. “We proposed AMSA and Teck to perform an optimization process of the mill liners designed for the specific processes of each operation so new equipment could be installed ready to use,” said Domínguez, stating that he expects both projects will achieve a smooth ramp-up of their mills and equipment because they will start with liners designed specifically for those environments.
Discussing ME Elecmetal’s approach, Domínguez added: “When we take on a project, we are not only looking for excellence in the manufacturing of the spare part or the liner, but also on the interaction of that component with the mill, the crusher, the equipment, the way they operate and the impact that will have on the tonnes per hour the mill or the crusher will yield, and/or in the mineral recovery.”
On the topic of equipment customized to a particular project, Christian Cavagnaro, managing director of TAKRAF Chile, gave the example of his company’s work at Codelco’s Chuquicamata underground mine, noting that a project of this scale and complexity requires a lot of work to lower operating costs and reach the deposit.
Cavagnaro revealed that TAKRAF installed a high-power, high-capacity conveyor belt system, introducing gearless drive technology. “Gearless technology is not new, but it has only recently been introduced to conveyor belt systems,” he said, elaborating: “We chose gearless technology because of its energy efficiency – CO2 emissions are reduced by ~66% as compared to diesel truck engines for the same copper production volume – and operational costs are reduced, as they require much less maintenance.”
Considering the size of the conveyor, TAKRAF’s belt technology partner also developed a new tension range belt to transport the material under such an extreme condition. “Since you cannot make a 6 km long belt, you have to do it in parts and splice the joints,” explained Cavagnaro, continuing: “In the case of Chuquicamata this project achieves a number of world firsts, boasting the highest conveyor drive power of 58 MW and the strongest resistance belt in the world.”
Sistemas de Transporte de Materiales (STM) is involved in designing and engineering customized conveyor belts, receiving the basic engineering from the client and then designing equipment for a specific application depending on the project and environment, according to Andres Osorio, STM’s general manager. He gave the example of STM’s work with Collahuasi at more than 5,000 m above sea level: “Conveyor belts are high tonnage equipment, in general, which require maintenance and are subjected to adverse conditions.”
Osorio also highlighted how conveyor belts reduce carbon footprint because they compete against trucks. “Just recently electric trucks and trucks that can use green hydrogen are appearing, but those technologies are in their infancy. Conveyor belts, on the other hand, are a mature solution that transports material efficiently because it works continually and with electric power,” he said, adding that even though conveyors represent a higher initial investment depending on the project, conveyors not only decrease the carbon footprint but also the cost of tons transported due to savings in fuel.
The material handling space has various niches, from crushers and mills to conveyor belts and vibrating screens. Haver & Boecker’s mining division (known as Haver & Boecker Niagara) produces technologies and solutions related to the classification and separation of solid materials – mainly vibrating screening machines, screening media (rubber and PU), and wire mesh. Illustrating the importance of this machinery to mineral processing, Roberto Montiglio, general manager – Andean region, and global T.U manager for spares and services at Haver & Boecker Niagara, said: “An unplanned stop of a vibrating screen for five hours, for example, can create a bottleneck which costs (due to lost production) two or three times more than the equipment itself.”
With that in mind, Montiglio discussed the company’s two main product lines related to condition monitoring, industry 4.0, and IoT: “One is a traditional condition monitoring system where you install sensors on the machine to collect data, and the other which is currently very successful, especially in light of the pandemic situation, is a remote monitoring system which sends data to a cloud network every five minutes, seven days a week, 365 days a year. This data is then analyzed through a machine learning system to inform decision making and predict mechanical problems up to four weeks in advance.”
Image courtesy of Metso Outotec and Juan Carlos Recabal