That is exactly why robust, density-compensated level measurement has become a ‘must-have’ rather than a ‘nice-to-have’. Among the available solutions, the VEGABAR 86 has emerged as a smart, durable and low-maintenance option for plants dealing with tough slurry conditions and constantly shifting process variables.
Why density-compensated level measurement?
Flotation cells rely on a stable froth layer to effectively separate valuable particles from waste. The chemistry is simple on paper: aerated slurry forms bubbles, valuable particles cling to the bubble surfaces and the froth layer transports them to the top for removal. But in reality, maintaining that froth layer at the right thickness is anything but simple.
If the froth is too thin, it lacks the buoyant structure needed to carry hydrophobic particles upward. If it’s too thick, it signals excessive reaction time, often meaning that less of the medium is being processed, throughput drops and energy and reagent costs rise.
Complicating this further is constantly changing slurry density. Feed variations, solids loading, air entrainment and chemical dosing all shift the density profile inside the tank. Without compensation, a level sensor might misread the process, giving operators a false sense of stability while efficiency slides.
A density-compensated level measurement solves this by simultaneously measuring both level and density. The VEGABAR 86 uses electronic differential pressure to calculate accurate level values even when solids content swings. This stabilises the control loop and lets operators keep the froth exactly where it needs to be.
Not for the-faint hearted
Flotation cells operate in extremely demanding conditions. They are constantly exposed to sudden changes in density and varying solids content, while turbulent surfaces caused by aeration create additional instability. Over time, continuous buildup and abrasion from suspended solids can significantly impact equipment integrity.
The sticky nature of froth layers further complicates the process, as do pressures typically ranging between +80 and +200 mbar and process temperatures from +25°C to +35°C. Many traditional instruments struggle to withstand these challenges: mechanical components wear out, impulse lines become clogged, capillaries lose their accuracy and the need for frequent cleaning can severely hamper productivity.
Standing out
This is where the design of the VEGABAR 86 stands out. The VEGABAR 86 is purpose-built for challenging environments characterised by sticky, abrasive, and slurry-heavy processes. What sets it apart is VEGA’s proprietary CERTEC ceramic measuring cell, which ensures long-term stability and performance, even in settings where abrasion is a constant threat.
This ceramic sensor resists wear far more effectively than traditional metallic diaphragms, particularly when exposed to slurries with high solids content. As a result, it experiences less measurement drift and is far less prone to failure, reducing the operational headaches often associated with froth flotation cells.
Another important advantage of the VEGABAR 86 is its design, which eliminates the need for mechanical components such as capillaries or impulse lines. This means operators do not have to contend with blockages, signal delays or the regular maintenance routines involving hot water and compressed air that other instruments require. The absence of these mechanical parts contributes to greater measurement reliability and ease of use.
Additionally, the VEGABAR 86 can simultaneously measure density and level. This integrated capability empowers operators to respond swiftly to changing process conditions, such as sudden collapses in the froth layer or fluctuations in solids loading, ensuring more consistent control and improved process stability. The instrument employs electronic differential pressure by digitally processing signals from two linked sensors, rather than relying on fluid-filled capillaries. This approach maintains high accuracy even as environmental factors such as temperature, vibration or leaks vary.
For plants that have implemented density-compensated level measurement in their flotation cells, the benefits are evident from the start. The foam layer becomes more stable, leading to increased recovery rates and allowing operators to spend less time manually adjusting levels. Consistent froth formation also means that plants can avoid overdosing on collectors or frothers, which helps to reduce reagent consumption. Finally, the wear-free ceramic cell and absence of mechanical parts translate into lower maintenance requirements, fewer unplanned stoppages and a longer lifespan for the instrument.
A strong match
Across the African mining sector, equipment reliability is a massive factor in operational continuity. Remote locations, abrasive ores and fluctuating plant feed make stable measurement technology essential.
The VEGABAR 86’s ability to withstand heavy slurry conditions while at the same time still providing density-compensated accuracy makes it especially well-suited to flotation cells used in African gold, PGM, base metal and phosphate processing plants. It fits the geometry of rougher and cleaner cells, and its ceramic sensing technology performs well even when buildup is unavoidable.
Final thoughts
Flotation efficiency rises and falls on control, particularly the control of level and density. Trying to manage flotation with instruments that drift, clog or can’t cope with density changes is essentially running a plant with crossed fingers.
The VEGABAR 86 gives operators a stable, low-maintenance and highly accurate way to control the froth layer and keep yield consistent over the long term. With its CERTEC ceramic cell and electronic differential pressure technology, it offers a combination of durability and precision that directly supports production efficiency.
For plants looking to improve recovery rates without increasing reagent or maintenance costs, density-compensated level measurement with the VEGABAR 86 is one of the smartest upgrades available.
