Although vertical mills have been integral to FLS’s range of mineral processing solutions for some time, the company is continually improving this technology to boost metal recovery while advancing its sustainability goals. These ongoing innovations make the mills more efficient and environmentally friendly, supporting customers as they strive for both productivity and responsible resource use.
According to Peter Wulff, Global Product Line Manager for Vertical Regrind Mills at FLS, vertical media mills use friction to break down materials, rather than forceful collisions, resulting in more efficient grinding. As ore grades decrease globally, these mills are becoming increasingly important in helping mines extract more valuable minerals from lower-quality deposits.
“As miners seek ways to maintain or improve recoveries from deposits whose ore grades are in decline, vertical grinding mills offer the advantages of internal classification and energy savings in one compact footprint,” says Wulff. This means customers can process more material efficiently, reducing the space and energy required for operations. By reducing energy consumption and water use, these mills not only lower operational costs but also help mining companies meet environmental targets.
The vertical orientation of the grinding chamber means that the basic laws of physics work in our favour to minimise overgrinding as finer particles can be discharged from the mill quickly , while coarser particles are held inside the grinding media charge until further reduced in size. This design allows for finer grinding while using less energy than traditional horizontal ball mills, making the process both cost-effective and environmentally responsible.
The vertical footprint of FLS’s vertical grinding mills brings the advantage of occupying a relatively small footprint in a process plant.
Vertical mills are recognised for their economical energy consumption compared to horizontal mills, achieving up to 25 to 30% energy savings. This translates to a lower carbon footprint for mining operations. For deposits containing copper, iron, and lead-zinc ores, these energy savings increase the profitability of downstream recovery processes, helping customers achieve better financial and environmental outcomes.
A standout in FLS’s line-up is the FTM tower mill. Featuring a central agitator screw as the only moving part in contact with the slurry and steel media, this design reduces both energy and media consumption, especially in tough ore applications. Additionally, the high concentration of solids fed into the mill means less water is needed during secondary and tertiary grinding, further lowering operational costs and supporting sustainability.
The robust construction and durable wear materials of these mills increase operational reliability, while advanced management software helps operators maximise performance. For customers, this means improved uptime, less unplanned maintenance, and a higher return on investment.
Building on the success of the FTM tower mill, FLS also offers the VXPmill for finer grinding applications, further expanding its portfolio to meet diverse processing needs. The VXPmill uses ceramic media rotated by a variable speed disc assembly, allowing it to be tailored for specific tasks. Designed for ultra-fine grinding, it can easily achieve product sizes below 20 microns, making it ideal for applications where a finer product is required.
This system features a modular impeller with removable discs and spacers, allowing operators to adjust the number of discs in operation. This flexibility helps achieve the desired product size without wasting energy, further increasing efficiency and reducing operational costs for customers.
Another advantage of vertical mills is their compact design. “Having a reduced footprint in comparison to horizontal mills of the same capacity can support customers’ plant space optimisation, while also requiring less costly civil engineering infrastructure for its base,” says Wulff. This makes vertical mills easier to retrofit into existing plants, particularly where space is limited, saving both time and money on construction.
The FLS Tower Mill (FTM) delivers efficient secondary and tertiary grinding, achieving up to 50% lower energy consumption while maintaining high grinding performance.
Lower capital spending is another customer benefit, as many components are factory tested and pre-assembled, allowing for quick installation and commissioning. This results in shorter project timelines and faster returns on investment. Together with energy efficiency and high operational uptime, these features help deliver the lowest total cost of ownership for operators.
Demonstrating the rising demand for this technology, FLS recently received an order from a customer in India for 18 FTM-5000 vertical tower mills—the largest order of its kind for both FLS and the wider industry. These mills are set to power one of the world’s most efficient iron ore beneficiation plants, highlighting the global shift towards more sustainable and efficient mineral processing.
Notably, these vertical grinding mills will be the largest ever built and will be used in two separate grinding stages. In the first stage, FTM tower mills receive output from FLS’s largest HPGRs (High Pressure Grinding Rolls), handling tertiary grinding tasks. The second stage uses FTM5000 mills to further increase iron content, ensuring high efficiency and optimal resource use throughout the beneficiation process.