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1

Comparison of Jameson cell and jet diffuser flotation column

Bilir K., Ucar A., Sahbaz O., Gursoy H., Oteyaka B.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 1

174--181

EN

A Jet Diffuser Flotation Column (JDFC) is a newly designed flotation device which resembles the Jameson cell (JFC) in terms of operational principles, but it has an important difference regarding to the structural characteristics in the downcomer. The main difference of JDFC is the diffuser type of downcomer which has been designed using the hydrodynamic consideration and fluid mechanics principles. The aim of the design was to increase the device efficiency for coarse particle flotation. Therefore, the turbulence occurring at the end of the downcomer was reduced, and the detachment probability of the coarse particle decreased. In addition, a homogenous and stable foam zone in the cell was obtained. According to the experimental results carried out in a pilot scale showed that not only higher flotation performance in comparison to the Jameson cell was obtained specifically for the coarse particles but also the quiescent froth layer was acquired under the given conditions. In these experiments, a vertical pipe of JDFC having an inlet diameter of 60 mm and outlet diameters of 115, 125 and 135 mm was used with the separation tank with the diameter of 390 mm. By using the data, the pilot scale JDFC with the 4100 mm vertical pipe integrated with the separation tank was produced, and the flotation tests were carried out by using a talc ore. Finally, the talc recovery of 90% was obtained using the JDFC for the particle size of 350 μm.

2

Water contact angle on corresponding surfaces of freshly fractured fluorite, calcite and mica

Kowalczuk P. B., Akkaya C., Ergun M., Janicki M., Sahbaz O., Drzymala J.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 1

192--201

EN

Advancing and receding contact angles of water with corresponding surfaces of freshly fractured calcite, fluorite and mica were measured. The corresponding surfaces were obtained by mechanical splitting of a small lump of each mineral into two pieces. Theoretical considerations revealed that depending on the mineral cleaving plane, surfaces created by splitting into halves can be either identical or entirely different as far as their surface chemical composition is concerned. It was experimentally established that receding and advancing contact angles measured on the corresponding surfaces of fluorite, calcite and mica were identical for the sessile drop method. When the contact angle was measured by the captive bubble approach, there were small differences in the contact angles measured on the corresponding surfaces of fluorite. It was most probably due to surface irregularities and roughness, and therefore different times needed to rupture the liquid film between the bubble and solid surface.

3

Recycling of colemanite tailings using the Jameson flotation technology

Ucar A., Sahbaz O., Kerenciler S., Oteyaka B.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 2

645--655

EN

In this study, beneficiation of colemanite minerals from tailings of the Emet Boron Processing Plant using a laboratory scale Jameson flotation cell was investigated in detail. Effect of some working parameters of the Jameson cell such as jet length, plunging depth of downcomer, and bias factor was studied for the flotation performance of colemanite. The results showed that all parameters showed a significant effect on colemanite flotation using the Jameson cell which was the first time used in boron flotation with a negative bias factor. The results also indicated that a high recovery could be obtained with a worthy grade values by the negative bias factor. According to the results obtained at the bias factor of -0.3, jet length of 3 cm, and plunging depth of 20 cm, B2O3 content of the sample increased to approximately 46% from 36.8% with a recovery of 98.47%.

4

In search of an efficient frother for pre-flotation of carbonaceous shale from the kupferschiefer stratiform copper ore

Kowalczuk P. B., Buluc B., Sahbaz O., Drzymala J.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 2

835--840

EN

This papers shows that frothers such as aliphatic alcohols (CnH2n+1OH), poly(propylene glycols) (HO(C3H6O)mH), poly(propylene glycol) alkyl ethers (CnH2n+1O(C3H6O)mH) and poly(ethylene glycol) alkyl ethers (CnH2n+1O(C2H4O)mH), can be used for collectorless flotation of a sample of carbonaceous copper shale manually separated from the Kupferschiefer stratiform copper ore. It was shown that flotation is influenced by the type and dose of frothers. The best flotation results were obtained with tri(propylene glycol) butyl ether C4P3, tri(propylene glycol) propyl ether C3P3 and tri(propylene glycol) P3. For these frothers, the yield vs. frother dose relationship was in the form of convex curves indicating that carbonaceous copper shale can float at relatively low dosages of the frother. It means that these frothers can be used for pre-flotation of carbonaceous matter from the investigated copper ore. Other frothers formed concave yield–frother dose relationships and were less effective.

5

Determining optimal conditions for lignite flotation by design of experiments and the halbich upgrading curve

Sahbaz O.

Physicochemical Problems of Mineral Processing

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2013

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Vol. 49, iss. 2

535--546

EN

In this study conditions for flotation of low rank coal (lignite of Tuncbilek, Turkey) were investigated in detail. The experiments were performed using the 3-variable 2-level (23) full factorial experimental design with four base point replicates, and the results were analyzed by the regression model, Fischer test (F-test) and Halbich’s upgrading curve for the responses of ash content (or combustible matter grade) and the combustible matter recovery. The results obtained from the analysis indicated that while every factor considerably affected the combustible matter recovery, both collector (kerosene) and frother (AF65) significantly influenced the ash contents of the carbonaceous matter products. The only effective mutual interaction influencing recovery was caused by the kerosene-aeration interaction, while the interaction of kerosene-aeration and kerosene-AF65 and interactions of all factors (kerosene-AF65-aeration) were significant for the ash content of the products. Basing on the grade–recovery Halbich upgrading curve, regression model and a criterion for optimum of flotation results, it was found that a coal product with combustible matter grade of 91.09% and 71% combustible matter recovery can be obtained provided that it is processed at the higher level of kerosene (3 kg/Mg), higher level of frother AF65 (40 ppm) and lower aeration rate level of (0.16 cm/s).

6

Determination of turbulence and upper size limit in Jameson flotation cell by the use of computational fluid dynamic modelling

Sahbaz O., Ercetin U., Oteyaka B.

Physicochemical Problems of Mineral Processing

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2012

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Vol. 48, iss. 2

533-544

EN

In the coarse particle flotation, turbulence which can be treated as energy dissipation rate, is one of the most significant parameters effecting the recovery and grade. Therefore, determination of energy dissipation rate is very beneficial for delineation of coarse particle flotation and determining the maximum floatable particle size in any cell. In this study, Computational Fluid Dynamic (CFD) modelling for the Jameson cell has been carried out to determine the high turbulent regions and the effect on the upper floatable size limit. The CFD modelling has been utilized for determining the flow characteristics and hydrodynamic behaviour of the Jameson flotation cell. In parallel with this purpose the turbulence map of the cell has been determined and energy dissipation rate determined by using the CFD modelling. According to the result acquired from the CFD modelling, there are two main turbulent regions which are mixing zone in the upper part of the downcomer and critical region at the separation tank. While the high turbulence at the mixing zone supplies fine bubbles and fast collection of particles, the turbulence at the separation tank causes the main detachment of the bubble-particle aggregate. Then, the increase in turbulence in the tank causes the decrease of the maximum floatable size of particles. In addition, the average energy dissipation rate in the critical region has been determined and used for estimation of the maximum floatable particle size in the Jameson cell. Moreover, the effect of hydrophobicity has been discussed.