Review: Comparison of Ultrasonically Aided Zinc Beneficiation by Mechanical Flotation and Column Flotation Cell

Abstract

Zinc is a key beneficiary of economic development for the developing countries. While the global zinc mine production in 2019 was recorded as 13 million tons, the value of zinc mined in 2019, based on zinc contained in concentrate, was about $2.1 billion. Sphalerite or zinc blende (ZnS), which is the main source of zinc, provides more than 90 % of zinc productions today. Beneficiation is usually carried out by flotation to produce marketable concentrates (45–55 %Zn). The flotation, which is the most widely used separation process at fine sizes for the concentration of low grade complex Pb-Cu-Zn ores plays an important role in the global economy. In any concentration plant employing flotation technique huge quantity of ores are being processed. Thus, any increments in the flotation recovery are important to get higher profits and to ensure that resources are utilized optimally. In this review, a comparative evaluation was made between mechanical flotation (MF) [1] and column (CF) [2] cells with or without ultrasonic pre-treatment (UP) for zinc recovery from lead-zinc-copper ore and the effect of UP on the MF and CF experiments were investigated at the optimized conditions. When compared with the optimized parameters, UP increased zinc grade and recovery for both MF and CF techniques as supported by XRD patterns. Besides, the best zinc grade and recovery was obtained by UP with CF technique. So that, sphalerite mineral can be effectively beneficiated to produce saleable zinc concentrate product and UP with CF will lead to a higher metallurgical gains and improvements to Net Smelter Return (NSR). This positive effect of ultrasound, which is safe and eco-friendly, on the zinc flotation by both mechanical cell and column cell regarding zinc grade and recovery is in good agreement with the previous published works in the literature