Estimating Bubble Loading in Industrial Flotation Cells

Abstract

Bubble loading is the ratio of the weight of the solid particles to the bubble’s surface, and it has an effective role in the flotation efficiency. This paper investigates bubble loading an industrial processing circuit through considering the important role of the bubble diameter in calculating bubble loading, and the effect of the aeration rate and frother dosage on the bubble diameter. The ratio of the weight of solid particles to the bubble volume was estimated to be in the range of 8 to 24 g/L. Although increasing the aeration could result in increasing the weight of the particles attached to the bubbles, the bubble loading was reduced by increasing the aeration rate due to its impact on the bubble diameter and the percentage of bubble surface coverage. For example, when the aeration rate was increased from 45 to 146 m3/h, the bubble loading decreased from 23 to 12 g/L. By increasing the frother dosage from 70 to 150 mL/min, the bubble loading increased from 16 to 19 g/L.

Effect of air flow rate and froth depth on the flotation performance: An industrial case study in a 10 m³ cell

“…It should be noted that the explained factors can affect the pulp zone as well (Ostadrahimi et al, 2021). It has been reported that higher air flowrate results in decreased bubble loading (Ostadrahimi et al, 2019), which leads to the formation of weaker bubbles. In the current study, when the amount of air flowrate increased from 45 to 146 m 3 /h, the time of bubbles coalescence and bursting reduced from 9 s to 5 s. In other words, the rate of bubbles coalescence increased by about 80%, which showed a negative effect on the flotation concentrate recovery.…”