Mining has spent the better part of a century throwing steel balls at rocks and drowning the result in millions of gallons of water. It’s a process that is loud, incredibly expensive, and increasingly hard to justify in a world where “ESG” isn’t just a buzzword: it’s a license to operate. The industry has been waiting for a “break glass in case of emergency” technology to fix the grinding circuit.
That emergency is here. Copper grades are falling, energy costs are volatile, and water is becoming a luxury many mines can no longer afford.
The announcement in March 2026 that Metso and Loesche have formed a strategic alliance to bring Vertical Roller Mill (VRM) dry grinding technology to the mining masses isn’t just another corporate handshake. It’s a direct challenge to the supremacy of the wet mill era. For decades, the VRM has been the workhorse of the cement industry. Now, it’s coming for hard rock mining.
If you’ve been watching the comminution space, you know the SAG (Semi-Autogenous Grinding) and ball mill circuit has been the undisputed heavyweight champion. But heavyweights get slow. They get bloated. The Metso-Loesche alliance is betting that the future of mining is dry, lean, and vertical.
The Mechanical Shift: Why Vertical Wins
Traditional horizontal mills are energy vampires. You’re essentially using gravity to drop heavy steel balls onto ore, hoping for the best. It’s inefficient. A huge percentage of that energy is wasted as heat and noise rather than actually breaking the rock.
The VRM operates on a completely different logic. Instead of a rotating drum filled with steel media, you have a stationary table with massive rollers that apply hydraulic pressure directly to a bed of material.
Modern mineral processing plant at sunrise highlighting advanced modular design.
Think of it as the difference between hitting a nut with a hammer (ball mill) and crushing it with a nutcracker (VRM). The nutcracker is controlled, precise, and uses far less effort to get the job done. By utilizing a “bed of material” for grinding, the VRM achieves mineral liberation that horizontal mills simply can’t match.
The strategic calculus here isn’t subtle: VRMs can replace High-Pressure Grinding Rolls (HPGRs), primary and secondary horizontal mills, and even tertiary stirred mills. It’s a flowsheet simplifier. One machine doing the work of three.
The 40% Energy Dividend
Let’s talk about the brutal numbers. Metso and Loesche are signaling energy savings of up to 40% compared to traditional tumbling mill circuits.
40 percent. That’s not a rounding error. That’s the difference between a project being a “go” or staying in the ground at current power prices.
In a traditional SAG-ball mill circuit, you are fighting physics. In a VRM, the grinding force is applied directly to the ore bed. Because the material stays in the grinding zone for a shorter duration and is removed as soon as it reaches the required fineness (via an integrated classifier), you aren’t “over-grinding” material that’s already small enough.
Over-grinding is the silent killer of mine profitability. It wastes energy and creates “slimes” that make downstream recovery a nightmare. The VRM provides a steeper particle size distribution. You get exactly what you want, when you want it, with 40% less juice from the grid.
Diagram illustrating the 40% energy reduction in VRM circuits vs. traditional SAG mills.
Killing the Consumables Bill
One of the most annoying recurring costs in any mill manager’s budget is grinding media. We’re talking about thousands of tons of steel balls that are literally designed to be destroyed. You buy them, you drop them in a mill, they wear down, and you buy more. It’s a never-ending cycle of logistics and expense.
The VRM removes the need for grinding media entirely. No balls. No rods. No massive liners that need to be swapped out every few months in a high-risk maintenance shutdown.
By using the ore to grind the ore: facilitated by those massive hydraulic rollers: you eliminate one of the largest Opex items on the balance sheet. For a remote copper mine in the Andes or the Outback, the logistics of hauling thousands of tons of steel balls to the site every year is a massive headache. Removing that variable is a game-changer for copper processing efficiency.
Water: The Ultimate Dealbreaker
This is where the Metso-Loesche alliance hits its stride. We are moving toward a reality where dry processing isn’t a “nice to have”: it’s the only way to get a permit.
The mining industry is currently one of the largest consumers of water on the planet. Traditional wet milling requires a massive liquid interface to move material through the circuit. This leads to tailings dams: massive, high-risk structures that store toxic slurry.
The VRM is a dry grinding technology. By removing water from the grinding stage, you open the door to advanced flowsheets like coarse particle flotation and dry magnetic separation.
Imagine a copper mine that doesn’t need a traditional tailings dam because it isn’t producing a wet slurry. Imagine being able to dry-stack your waste. This isn’t just better for the environment; it’s better for the bottom line. It reduces the risk of dam failures, simplifies the permitting process, and: most importantly: it saves the water for the communities that actually need it.
Mining professionals at a South American site discussing global resource extraction.
For copper mining specifically, this is the “holy grail.” We need more copper for the energy transition, but most of the remaining big deposits are in water-stressed regions like Chile, Peru, and Arizona. You can’t build a 100,000-tpd wet mill in a desert forever. The math doesn’t work.
HPGR vs. VRM: The New Rivalry
For a while, High-Pressure Grinding Rolls (HPGR) were the darlings of the “dry-ish” grinding world. They offered better energy efficiency than SAG mills and were gaining traction.
But the VRM might just eat the HPGR’s lunch.
While HPGRs are great at crushing, they often require a separate milling stage to get to the final product size. The VRM integrates the grinding and the classification into one unit. It can take a larger feed size and produce a finished product in a single pass.
The Metso-Loesche partnership is leveraging Loesche’s 2,400+ installations in other industries to prove that this tech is mature. This isn’t a science experiment. It’s a proven industrial tool being “ruggedized” for the abrasive, high-tonnage reality of hard rock mining.
Is the Wet Mill Actually Dead?
Now, let’s be real for a second. We aren’t going to wake up tomorrow and see every ball mill in the world sold for scrap. Wet milling has a century of momentum behind it. It’s understood, it’s predictable, and for certain ore bodies, it still makes sense.
The research is clear: the VRM is a significant alternative, but it’s not a universal replacement: yet. Some ores might be too sticky or require specific chemical environments that only a wet circuit can provide.
However, the “default” choice is shifting. In 2026, if you are designing a new greenfield project and you don’t evaluate a VRM dry grinding circuit, you are leaving money on the table. You are also taking on unnecessary ESG risk.
Skillings Mining Review media highlighting industry expertise and commodity analysis.
The 2026 Outlook: A New Standard
The alliance between Metso and Loesche marks the inflection point. Metso brings the global service network and the deep understanding of mining flowsheets; Loesche brings the specialized VRM engineering. It’s a powerhouse combination that aims to de-risk the transition for cautious mining majors.
As we look at the outlook for critical minerals, the pressure to produce more with less has never been higher. The days of “brute force” mining: using cheap energy and endless water to compensate for low efficiency: are over.
The VRM isn’t just a new machine. It’s a signal that the industry is finally growing up. We’re moving from the age of the “big hammer” to the age of the “smart crush.”
Comparison chart of Opex: VRM vs. SAG/Ball Mill over a 10-year project life.
The Bottom Line
The Metso-Loesche alliance is a direct response to a mining industry that is being squeezed from all sides. If you can cut your power bill by 40%, stop buying steel balls, and drastically reduce your water footprint, you do it.
The era of the wet mill isn’t going to end with a bang, but with the quiet, efficient hum of a vertical roller. The technology is here, the partnership is solidified, and the water is running out.
The strategic calculus is simple: evolve your flowsheet or watch your margins evaporate. There’s not enough water to go around, and there’s certainly not enough cheap power to waste. 2026 is the year dry grinding stops being a “future tech” and starts being the standard.
Welcome to the new reality of comminution. It’s dry, it’s vertical, and it’s about time.
