Image courtesy of Tribeca Resources

The Chilean mining industry faces significant challenges related to the hardness, abrasiveness, and geological complexity of its mineral deposits. These challenges are becoming tougher as surface level economically viable ore has long been depleted. “As pit depth increases, challenges arise because the rocks are harder, and the ore grades are lower. In Chile, since the biggest mines are old, ore grade is decreasing rapidly,” said Cristian Cifuentes, general manager Chile and Argentina at Orica.

Drilling and blasting companies must deal with these challenges head on. Understanding the characteristics of the rocks, however, is helping ensure optimal, efficient solutions. “Rock study is crucial in the mining industry, as rock characteristics affect all processes, including crushing, one of the most energy-intensive and costly mining processes. Optimizing our understanding of rock properties can generate enormous savings in productivity and costs,” said Trinidad Carmona, Co-CEO at Drillco.

Drillco is working with the Imperial College of London and institutions in France and Sweden to develop a model leveraging sensors and algorithms for rock fragmentation analysis. “By understanding the intricacies of rock breakage under various conditions, we expect this model to optimize mining processes to increase productivity and obtain more ore with less environmental impact,” Carmona continued.

Many Chilean deposits comprise of rock types such as andesite and diorite, which range from 6-7 and 7 on the Mohs scale respectively, which is roughly equivalent to the hardness of a steel nail. These hard and abrasive rocks accelerate wear and tear on drilling equipment, leading to increased maintenance costs and frequent downtime. Drill component manufactures are looking at ways to help equipment to overcome this challenge. Jean Paul Droguett, general manager at Mincon, said: “Customized steel tailored to different rock types and drilling conditions ensures longevity and reliability in diverse mining environments. Understanding the varied lithologies present in mining operations, Mincon develops products designed to adapt to different drilling methods and rock types.”

Steel quality ensures these benefits, echoed Tomas Buttazzoni, general manager at Technosteel: “The quality of steel is paramount to the performance and durability of our products. Inconsistent steel quality can lead to manufacturing defects and product failures, resulting in costly downtime and rework.”

“Changing drill bits can lead to downtime, thus diminishing client productivity”, said Ignacio Bello Marambio, general manager at Diamantina Christensen. “We have developed various designs based on terrain conditions – including factors like fracturing, compactness, competency, and hardness, and also capacity of drill rigs used. These tailored designs enable us to offer products that optimize performance and efficiency across diverse drilling conditions.”

An explosion of benefits
By understanding rock properties such as hardness, density, and the presence of natural fractures, the appropriate type and amount of explosives can be selected. This ensures that the energy from the explosives is effectively used, leading to better fragmentation, explained Jorge Blazquez Hernandez, regional manager at Maxam: “Our X-Energy solution allows us to adjust the energy of explosives based on rock characteristics. Through data collection and mathematical modeling, we determine the exact quantity of explosives required for fragmentation.”

Effective energy distribution is crucial for maximizing productivity and minimizing costs associated with re-blasting and secondary handling. According to Cifuentes, there is no better way to optimize than through digital tools: “We introduced our new 4D technology, an advanced explosive product that enhances energy distribution… In parallel, our digital solution, Rhino, has been pivotal in improving rock mass recognition and optimizing our blasting designs for better client outcomes.”

Chilean deposits are characterized by many faults and fractures, which demand precise blasting techniques to ensure effective resource extraction and minimize dilution of the ore. “Knowledge of the rock mass properties allows for the design of more effective blast patterns”, said Pablo Wallach, vice president of technology, innovation and marketing at Enaex. “We developed a new version and tools of Enaex Bright, a platform that utilizes machine learning to predict bench hardness based on data from previous benches. This information allows for optimized blast designs, improving efficiency and reducing maintenance costs for crushers and sag mills.”

Rocking the flotation circuit
The mineralogies characterizing Chile’s mining sphere have impacts continuing up the value chain, said Gülden Ergün, mining sales manager at BASF: “In Chile, in general minerals are complex so the process of extraction is also intricate, and very time-consuming… We have solutions that increase the efficiency while reducing freshwater consumption and process time. Our flocculant Rheomax DR, an advanced polymer with high density, allows for water recovery up to 7% and reduces carbon emissions. For leaching, we have a product called LixTRA, a powerful reactive that increases copper recovery by 3-5%, while not impacting SX-EW processes as well as reducing the impact on the environment and costs.”

Understanding the specific chemical properties of the ore helps in tailoring the beneficiation process to improve the purity and yield of the final product. “Every operation has unique particularities and necessities”, said Ricardo Capanema, global marketing and business development director at Syensqo.

Chemical compounds play a critical role in maximizing yields during flotation. “The flotation process lies at the core of mining operations; depending on the efficiency of the reactive chemical compounds used, you can have very large differences in yield, sometimes 30 to 50%” emphasized Daniel Araya, general manager, Pochteca Chile.

A customized approach is increasingly important as mining operations face more challenging ore bodies and stricter environmental regulations, necessitating precision in chemical applications to maintain profitability and sustainability. “We take geological samples from our client’s mining operations, analyze them, and produce customized chemical compounds that are best suited for our client’s specific mining needs. This approach allows us to create product that can maximize our client’s mining yields, depending on the specific geology that they deal with,” continued Araya.

Advances in data analytics and machine learning allow for predicting optimal chemical usage and process adjustments to enhance efficiency and reduce waste. “Digitalization enables us to analyze historical data to understand how various mineralogies react to different chemicals, allowing us to identify the most effective formula for a specific operation's mineral,” highlighted Capanema.

Declining ore grades have been observed across the industry. Antofagasta's copper output, for example, fell by 10.4% in 2022 due, in part, to lower ore grades. Average sulfide ore grade in Chilean copper mines decreased 27% from 2005-2016, according to Cochilco. There is also a depletion of oxidized resources, which will mean 66% lower production of SX-EW cathodes by 2027. This decline necessitates the processing of larger quantities of ore to extract the same amount of copper, leading to higher operational costs and energy consumption; "production costs have increased due to declining mineral grades," said Jorge Soto, country manager at Astec Industries.

Customized solutions from drilling and blasting firms and laboratories will be critical in addressing these challenges to improve efficiency and sustainability in mining operations.