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Investigating the effects of ultrasonic energy on the flotation behavior of pyrite and galena minerals

Horasan Umit, Tanrıverdi Mehmet, Ciçek Tayfun, Polat Mehmet

Physicochemical Problems of Mineral Processing

2020

Vol. 56, iss. 3

538--547

Although pyrite is one of the more abundant the earth crust, it has low economic value. When it reports to the concentrate during flotation along with the valuable minerals, it decreases the grade of the valuable minerals and leads to an increase in smelting costs. Numerous modifications have been suggested in the literature to increase the selective recovery of pyrite containing base metal-sulfide ores. The use of ultrasonic applications is one such method. In this study, the effect of the ultrasonic application on the flotation behavior of galena and pyrite mineral was investigated through systematic Hallimond Tube experiments. In the initial phase of the experiments, the optimum flotation conditions (particle size, pH, amount of air, and amount of reagent) were determined for the two minerals. Subsequent experiments were carried out under these optimums to distinguish the effect of the ultrasonic application. The influence of how the ultrasonic application was applied (i.e. before and during the conditioning stage or before the re-flotation of the concentrate) was also studied. It was observed that the ultrasonic application had a strong activating influence if it was administered before or during the conditioning stage. The effect was similar to whether the minerals were floated individually or from their mixtures. However, when it was applied to a flotation concentrate before reflotation, it selectively displayed a depressant action for the pyrite to the extent that no depressants were needed. The results conclusively showed that the ultrasonic application could drastically improve the selectivity of the complex ores.

Frother-Assisted Flotation of Different Origin Pyrites

Milewski Kamil, Drzymala Jan

Inżynieria Mineralna

2019

R. 21, nr 1/2

143--150

Hallimond tube flotation of different origins pyrites (coal-derived, Rio Tinto and Huanzala) and copper –bearing shale, having different hydrophobicities determined by contact angle, were investigated in water and aqueous solutions of butyl diethylene glycol ether. Pyrites flotation depended on hydrophobicity, particle size fraction and frother concentration. Three regions of the yield-frother concentration plot were distinguished: Jones-Ray region at low frother concentration with decreasing yield due to entopic effects, Lyster region at medium frother concentration with increasing yield due to decreasing film stability and Zisman region at high frother concentration with decreasing yield due to surface tension drop. The flotation kinetics in the form of 1st order specific rate, equal to the kinetic constant, was similar for all three pyrites and was equal to 0.032±0.002 min-1, while their yield after 45 min flotation was dependent on pyrite origin.

W celce Hallimond poddano flotacji piryty różnego pochodzenia oraz łupek miedzionośny. Wśród pirytów były to piryt węglowy, Rio Tinto oraz Huanzala. Miały one różną hydrofobowość, którą mierzona jako kąt zwilżania dla wody i roztworów eteru butylowego glikolu dietylenowego. Spieniaczowa flotacja pirytu zależała od hydrofobowości, stężenia spieniacza oraz rozmiaru ziarn. Na wykresie wychód-stężenie spieniacza wyróżniono trzy zakresy flotacji: Jonesa-Raya przy niskim stężeniu spieniacza, gdzie zachodzi spadek wychodu wynikający z efektów entropowych, Lystera przy średnim stężenia spieniacza, gdzie zachodzi wzrost wychodu i zakres Zismana przy wysokiej koncentracji spieniacza powodującej obniżenie wychodu ze względu na spadek napięcia powierzchniowego. Kinetyka flotacji w postaci prędkości specyficznej 1-szego rzędu równa stałej kinetycznej 1-szego rzędu była podobna dla wszystkich trzech pirytów i wynosiła 0,032±0.002 min-1, podczas gdy ich wychód po 45 minutach flotacji był uzależniony od pochodzenia pirytu.