2016, 147−154 Physicochemical Problems of Mineral Processing

Abstract: In this paper the importance of definition of hydrophobicity and aquaoleophilicity in terms of contact angle as well as the properties of water films in flotation and oil agglomeration were briefly presented. It was shown that the hysteresis of contact angle for a considered system depends on the way of measurement and geometry of the system due to the presence of other that excess pressure and capillary forces and buffering properties of the capillary force. It was suggested that, the measured advancing and receding contact angles should be, when possible, recalculated into the Young (rest, equilibrium) contact angle. It was discussed that quartz is not a good model of hydrophilic surface because its contact angle with a gas phase in water is not zero and that a spontaneous attachment between highly hydrophobic materials such as hydrocarbons and Teflon in dynamic system, such as flotation, does not occur

Evaluation of frothers based on properties of the solids/liquid/gas system

A methodology of selection of frothers for flotation process is presented in the paper. It is based on performing a series of fractionating flotation tests of a considered material at different doses of a selected frother and calculation of the mass balance of the process. Next, three steps are performed. The first one is determination of the frother dose and kinetic constant or specific rate, using the flotation limits plot relating maximum recovery and process rate, both at a selected maximum recovery of the considered material component. The second step is finding selectivity of separation by using the upgrading Fuerstenau plot, while the third element is frothers comparison plot in the form of selectivity versus process kinetics, at a selected maximum recovery, and also versus frother dose, for choosing the most suitable frother

Classification of Flotation Frothers

In this paper, a scheme of flotation frothers classification is presented. The scheme first indicates the physical system in which a frother is present and four of them i.e., pure state, aqueous solution, aqueous solution/gas system and aqueous solution/gas/solid system are distinguished. As a result, there are numerous classifications of flotation frothers. The classifications can be organized into a scheme described in detail in this paper. The frother can be present in one of four physical systems, that is pure state, aqueous solution, aqueous solution/gas and aqueous solution/gas/solid system. It results from the paper that a meaningful classification of frothers relies on choosing the physical system and next feature, trend, parameter or parameters according to which the classification is performed. The proposed classification can play a useful role in characterizing and evaluation of flotation frothers

Differentiation of organic carbon, copper and other metals content by segregating flotation of final Polish industrial copper concentrates in the presence of dextrin

Abstract. Existing and new data on production of two copper concentrates differing in copper, organic carbon and other metals contents by reflotation of the final industrial flotation copper concentrates from KGHM Polska Miedz S.A. in the presence of dextrin as a depressing reagent of the mineral particles containing organic carbon are presented in the pape

Spieniaczowa flotacja pirytów różnego pochodzenia

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

Concentration at the Minimum Bubble Velocity (CMV) for Various Types of Flotation Frothers

This paper presents the determination of a concentration at the minimum bubble velocity (CMV) for different types of frothers, such as straight and branched alkyl chain aliphatic alcohols, 1,ω-diols, poly(propylene glycol) and poly(ethylene glycol) alkyl ethers, n-alkyltrimethylammonium bromides, commercial frothers and others. The values of terminal rise bubble velocity were reviewed from the experimental data published in the literature for two different types of columns, i.e., a short PAS (used in Polish Academy of Sciences) of height (35 cm) and a long McGill of height (350 cm). The obtained empirical equation is universal and allows one to rapidly and accurately determine the CMV for all surfactants. The proposed empirical model can also be used to predict the terminal bubble velocity–frother concentration curve by knowing the maximum and minimum terminal velocities, as well as the values of CMV. Assessment and usefulness of frother characterization parameters (i.e., concentration at the minimum bubble velocity (CMV), dynamic frothability index (DFI) and critical coalescence concentration (CCC)) were shown in the flotation of coal

Classification of Flotation Frothers

In this paper, a scheme of flotation frothers classification is presented. The scheme first indicates the physical system in which a frother is present and four of them i.e., pure state, aqueous solution, aqueous solution/gas system and aqueous solution/gas/solid system are distinguished. As a result, there are numerous classifications of flotation frothers. The classifications can be organized into a scheme described in detail in this paper. The frother can be present in one of four physical systems, that is pure state, aqueous solution, aqueous solution/gas and aqueous solution/gas/solid system. It results from the paper that a meaningful classification of frothers relies on choosing the physical system and next feature, trend, parameter or parameters according to which the classification is performed. The proposed classification can play a useful role in characterizing and evaluation of flotation frothers