Decarbonization: Drill through Mill
Driving down emissions and costs
The United Nations’ Intergovernmental Panel on Climate Change indicated that to limit the global temperature rise to 1.5°C will require rapid, far-reaching, and unprecedented changes: human- caused CO2 emissions must decrease 45% by 2030 and reach net- zero by 2050. Mining accounts for 4-7% of global greenhouse-gas emissions, according to McKinsey. The path to net-zero carbon emissions is a global, multi-sector challenge, and developing road maps to achieving that goal requires industry commitment, innovation and new technological solutions. In the Western US, the mining services ecosystem is determined to provide these solutions.
Drill through mill
For traditional drill and blast methods, each ton of explosives is approximately equivalent to a thousand liters of emitted CO2. Typical consumption rates for explosives in underground mines can range from 0.5 to 1.0 kg/t of rock mined. If a mine processes 10 million t/y of rock, for example, the explosives required could range from 5,000 to 10,000 kg. This amount multiplied by emitted CO2 per ton becomes significant. Innovations at Dyno Nobel are aimed at changing this narrative, said Braden Lusk, chief technology and marketing officer: “Our technology, like Delta E2 (ΔE2), is instrumental because it allows us to adjust the energy and density of bulk emulsion in the hole based on insights from drilling. We can modify the density up to six times within a single borehole, ensuring explosive energy is applied precisely where needed.”
Applying this solution to operations at Rio Tinto’s Kennecott led to immense benefits. “Using TITAN bulk explosives and ΔE2 methodologies, we effectively delivered explosive energy, leading to a 15% increase in mill throughput and a 5-10% rise in the minus half-inch size fraction. Kennecott saved US$58.1 million as a result”, said Lusk.
By increasing mill throughput, energy consumption per ton of ore processed decreases due to more efficient use of equipment and processes, leading to lower emissions. This is crucial as crushing and grinding can consume up to 53% of the total energy used in a mining operation and account for approximately 46% of the total GHG emissions from the entire mining and processing operation, according to a study published in Nature. Gabi Knesel, vice president mining and minerals processing at Locus Mining delves into this further: “By enhancing recovery, mining clients can process less material to achieve the same output, which directly translates to lower CO2 emissions.”
Big benefits from bio-based solutions
100% biobased and made from renewable raw materials with a low carbon footprint,” Knesel emphasized.
Czech Republic based Draslovka also found a muse in mother nature in their Glycine Leaching Technology (GLT). “GLT utilizes glycine, which is nontoxic, biodegradable and recyclable, as a reagent. This amino acid was discovered by scientists at Curtin University in Perth, Australia, who found that plants absorb gold through the soil in the presence of glycine,” explained Greg Warren, group chief commercial officer and executive director.
Both solutions enhance the capabilities of current processes in gold leaching. For Locus Mining, the micelle size of biosurfactants, 20 times smaller than traditional surfactants, allows them to transport cyanide through smaller pores. For Draslovka, glycine allows cyanide to act as a targeted pistol extracting gold from a mixture of ores while it absorbs other materials like copper and gang metals.
What do these bio-based additives achieve?
“Draslovka’s GLT processes can reduce carbon emissions by approximately 35-36% per ounce of gold produced across the entire value chain… With our technology, we optimize cyanide use to ensure it is fully consumed, leaving only glycine in waste streams. This results in an 80-90% recycling rate of glycine for our customers and reduces cyanide usage by 30-80%, improving gold recovery without degrading it”, said Warren.
“At Locus Mining we conducted successful industrial trials with our biosurfactants in gold recovery, achieving improvements of over 3% in recovery rates. Depending on the size of the customer and the current price of gold—around US$2,500/oz—this can translate in increased revenue to our customers of over US$25 million,” said Knesel.
“The mining industry needs to embrace new technologies to meet the demands of decarbonization and efficiency improvements.”
Gabi Knesel, VP Mining and Minerals Processing, Locus Mining
Flotation solutions skimming off emissions
Focusing on flotation provides upstream benefits in the mill circuit. Coarse particle flotation (CPF) is a relatively new technology used to recover particles larger than 150 micrometers. Eriez pioneered the technology through development of HydroFloat. “HydroFloat allows for flotation at a coarser size, reducing the need for fine grinding during roughing. This reduces the required grinding size by about two and a half times for typical copper ore. Depending how CPF is implemented, it can reduce concentrator grinding energy by more than 20% and can increase metal recovery by 3 to 6%”, said Eric Wasmund, vice president of Eriez’s global flotation business.
Eriez also offers magnetic mill liners. According to, Jose Marin, director of minerals and materials processing: “These can last three to five times longer than rubber or metallic liners. This reduction in the frequency of liner replacement can represent big savings to any plant.”
This longer lifespan reduces the carbon emissions needed to manufacture new mill liners.
Monitoring systems are becoming increasingly important to maximize efficiency and minimize emissions in the flotation and leaching circuits, driving new innovations. Specialty chemical firm Solenis launched a new line of patented and patent-pending antiscalants, the Zalta 12 series, with this in mind: “These antiscalants are designed to operate effectively under challenging conditions and are paired with our unique monitoring systems to maximize operational runtime while reducing chemical usage. This approach also minimizes transportation needs, reducing carbon dioxide emissions,” said Shane Capazorio, corporate account executive.
A previous version of the technology, the Zalta MA11-556 patented heated slurry anti-scalant, helped address scale formation in a gold processing operation. “This allowed us to optimize the dosage, reducing cleaning frequency, translating to a 12-17 day increase in production, eliminating 8 to 13 cleaning procedures annually and addressing sustainability metrics like water usage,” added Renata Vinhas, applications project manager.
In the race to decarbonize mining, innovative solutions across the blasting, milling and processing stages are paving the way toward a more sustainable future. The mining industry is proving that meaningful reductions in CO₂ emissions are possible. Through tailored approaches, data-driven monitoring and bio-based advancements, mining operations are not only aligning with global climate targets but also unlocking cost savings and boosting operational resilience. Decarbonization, while challenging, is achievable and essential for the future of mining.
Article header image courtesy of Rio Tinto Kennecott