Slurry Agitator Tank: Key Equipment to Improve Flotation Efficiency

In the flotation process, the importance of the slurry agitator tank is often underestimated. However, effective contact and efficient interaction between ore, reagents, and air are key to improving flotation efficiency—and this is precisely the role of the slurry agitator tank.

Xinhai's slurry agitator tank has taken slurry agitator performance to a new level through fluid dynamics optimization.Tests have shown that it can improve the mineral recovery rate by more than 1%. (Based on a plant processing 10,000 tons per day, this translates to an annual revenue increase of over 1.5 million USD.)

01Disadvantages of traditional slurry agitator tanks

1.The structural design is unreasonable, and there are dead zones inside the tank

Traditional slurry agitator tanks typically feature a straight cylindrical body with a flat bottom design. This causes a sudden drop in flow velocity in areas more than 30 cm from the impeller, leading to the formation of permanent sedimentation zones.

Additionally, this structure results in uneven reagent distribution.

Testing at a lead-zinc mine revealed that the reagent concentration at the tank edges was only 43% of that in the central area, leading to excessive reagent consumption and significant waste.

2.Impeller design is backward

The impeller of a traditional slurry agitator tank typically has a small diameter, low linear speed (1–2 m/s), and a braided or spiral shape. This design results in weak agitation performance, inadequate mixing, and low negative pressure within the tank. As a consequence, the circulation capacity is reduced, and energy utilization is limited to only 35%, making it difficult to achieve an ideal agitation effect.

3.Poor adhesion efficiency

The conventional agitation method results in bubble coverage of less than 60%, leading to uneven bubble distribution and a limited mineral-gas contact area. Reagents are adsorbed onto the surface of mineral particles in a "spotted" pattern, resulting in low adhesion efficiency.

02Features of Xinhai Slurry Agitator Tank

The high-efficiency slurry agitator tank developed by Xinhai avoids the above-mentioned shortcomings. Designed from both the impeller and circulation systems, it features strong circulation capacity and thorough mixing.

1.Umbrella-Shaped Impeller System

Large diameter and high linear speed design: The impeller diameter is increased and paired with special alloy materials to enhance bending strength. Linear speed reaches 5–8 m/s, tripling the shear rate and significantly improving agitation capacity. The umbrella-shaped surface guides the slurry to form both axial main circulation and radial diffusive flow, increasing circulation volume by 220%. The negative pressure reaches 15–20 kPa, enabling forced mixing of reagent microbubbles.

2.Three-Stage Circulation Enhancement System

Built-in circulation body: The internal circulation structure confines high-energy agitation to the core zone. The flow rate inside the tank exceeds 3 m/s, ensuring forced convection of ore, reagent, and gas phases for complete mixing.

Vortex injection device: An inclined nozzle at the bottom sprays slurry at a pressure of 0.8 MPa, reducing bottom sediment to below 0.05%. A three-dimensional cross-flow field is formed, increasing the probability of bubble-mineral attachment to 92% (compared to ≤75% in traditional equipment).

03Effect of Slurry Agitation Tank on Flotation Efficiency

Measured data from a gold concentrator show that compared with traditional agitation tanks, Xinhai’s slurry agitation tank reduces reagent consumption by 14%, increases the bubble mineralization rate by 31%, boosts the roughing recovery rate by 1.1%, reduces power consumption per ton of ore by 17%, and improves the overall recovery rate by 1%.

04Application Cases of Xinhai Slurry Agitation Tank

1.Tibet Spodumene Project

Due to high altitude and low-pressure conditions, slurry concentration fluctuates significantly, causing frequent sedimentation in traditional agitation tanks. As a result, lithium recovery remained below 82%. After replacing with Xinhai’s slurry agitation tank, reagent dispersion became uniform, stabilizing the recovery rate at over 87.5%.

2.Chilean Copper Mine Project

The high-density slurry previously led to more than 5% sedimentation within 48 hours using traditional tanks. After switching to Xinhai’s slurry agitation tank, no visible sedimentation occurred during continuous operation. The copper recovery rate improved by 1.3%, and annual electrolytic copper output rose by 800 tons.

Conclusion

Xinhai’s high-efficiency agitator tank improves both mixing and flotation efficiency through a technical approach of structural innovation → flow field optimization → performance quantification.

When a 1% increase in recovery rate translates to billions of yuan in revenue, the slurry agitator tank is no longer just an optional “auxiliary device”—it becomes a critical component determining a mine’s profitability.