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- Ikumapayi, Fatai, et al.
(författare)
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Recycling of process water : effect of calcium and sulphate ions in sulphides flotation
- 2010
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Ingår i: Conference in Minerals Engineering. - Luleå : Luleå tekniska universitet. - 9789174390971 ; , s. 51-61
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The effects of major components of calcium and sulphate ions in process water on sulphide mineral flotation has been investigated through Hallimond flotation of pure sulphide minerals using tapwater and water containing sulphate and calcium ions as well as through bench scale flotation of complex sulphide ores using tapwater and process water and with tapwater in the presence of calcium and sulphate ions. Hallimond flotation indicated activation of pyrite and slight depression of galena and chalcopyrite in the presence of high concentration of major species of calcium and sulphate ions using potassium amyl xanthate as collector. Bench scale flotation indicated activation of zinc when processwater was used and flotation in tapwater containing calcium and sulphate ions presented similar but not identical results.
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- Ikumapayi, Fatai, et al.
(författare)
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Recycling of process water in sulphide flotation : Effect of calcium and sulphate ions on flotation of galena
- 2011
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Ingår i: 5th International Flotation Conference 2011. - Red Hook : Curran Associates, Inc.. - 9781618393951 ; , s. 222-249
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Konferensbidrag (refereegranskat)abstract
- The effects of major components of calcium and sulphate species present in recycled process water on galena flotation has been investigated through Hallimond flotation, zeta-potential, diffuse reflectance FTIR spectroscopy and XPS measurements using pure galena mineral as well as bench scale flotation tests using complex sulphide ore. The significance of process water species in flotation has been assessed using deionised water, process water and simulated water containing calcium and sulphate ions in experiments. In addition, the effect of temperature in bench scale flotation tests has also been examined.Hallimond flotation indicated lower recoveries of galena in the presence of calcium and sulphate ions using potassium amyl xanthate as collector. Calcium ions increase zeta-potential of galena while sulphate ions have no effect. FTIR and XPS studies revealed the presence of surface oxidised sulfoxy, hydroxyl and carbonate species on galena at pH 10.5 in deionised and process water, which surface species affected xanthate adsorption. Bench scale flotation using two different complex sulphide ores showed that galena recovery is better in process water than tap water at room temperature. Flotation results also indicated decrease of galenarecovery at temperatures lower than 22oC in either tap water or process water.
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- Ikumapayi, Fatai, et al.
(författare)
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Recycling of process water in sulphide flotation : effect of calcium and sulphate ions on flotation of galena
- 2012
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Ingår i: Minerals Engineering. - : Elsevier BV. - 0892-6875 .- 1872-9444. ; 39, s. 77-88
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Tidskriftsartikel (refereegranskat)abstract
- The effects of major components of calcium and sulphate species present in recycled process water on galena flotation has been investigated through Hallimond flotation, zeta-potential, diffuse reflectance FTIR spectroscopy and XPS measurements using pure galena mineral. The significance of process water species in flotation has been understood using deionised water, process water and simulated tap water containing equivalent calcium and sulphate ions concentration as in process water.Hallimond flotation indicated marginally lower recoveries of galena in the presence of calcium and sulphate ions using potassium amyl xanthate as collector. Zeta-potential shows the adsorption of calcium ions whereby the potential are seen to increase while sulphate ions have no significant effect. FTIR and XPS studies revealed surface calcium carbonate and/or calcium sulphate species in process water which affected xanthate adsorption. Presence of surface oxidised species such as sulfoxy, hydroxyl species on galena at pH 10.5 in deionised and process water was also revealed.
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- Ikumapayi, Fatai, et al.
(författare)
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Recycling process water in sulfide flotation, Part A: Effect of calcium and sulfate on sphalerite recovery
- 2012
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Ingår i: Minerals & metallurgical processing. - : Springer Science and Business Media LLC. - 0747-9182. ; 29:4, s. 183-191
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Tidskriftsartikel (refereegranskat)abstract
- In order to predict and minimize detrimental production problems due to the recycling of process water in sulfide ore processing, the influence of major species, calcium and sulfate in process water on sphalerite flotation was investigated through Hallimond tube flotation, zeta potential, diffuse reflectance Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) measurements using sphalerite mineral sample. Assessment of process water species in flotation was done using deionized water, process water and simulated water containing calcium and sulfate ions in experiments. Hallimond flotation shows increased sphalerite floatability in process water compared to deionized water, but no significant effect on the presence of calcium and sulfate ions in deionized water using isobutyl xanthate as a collector. The presence of calcium ions reduced the sphalerite's negative zeta potential, while at higher concentrations, a charge reversal occurred, at about pH 11. FTIR and XPS studies revealed the presence of surface-oxidized sulfoxy and carbonate species on sphalerite at pH 11.5 in deionized water, process water and water containing calcium and sulfate ions. These surface species do not influence xanthate adsorption.
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- Ikumapayi, Fatai, et al.
(författare)
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Recycling process water in sulfide flotation, Part B: Effect of H2O2 and process water components on sphalerite flotation from complex sulfide
- 2012
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Ingår i: Minerals & metallurgical processing. - : Springer Science and Business Media LLC. - 0747-9182. ; 29:4, s. 192-198
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Tidskriftsartikel (refereegranskat)abstract
- Hydrogen peroxide production was measured during the grinding of a complex sulfide ore, and its oxidizing effect on solid surfaces was investigated using Fourier transform infrared spectroscopy (FTIR) with diffuse reflectance attachment measurement. In turn, an attempt was made to correlate the formation of hydrogen peroxide, surface oxidation and sphalerite flotation. Additionally, in order to predict and minimize detrimental production problems due to the recycling of process water in sulfide ore processing, the effects of major components of calcium and sulfate species present in recycled process water and the effect of temperature on sphalerite flotation were investigated through bench-scale flotation tests using complex sulfide ores. The significance of process water species in flotation was studied using tap water, process water and simulated water containing calcium and sulfate ions. Formation of hydrogen peroxide was revealed during the grinding of the complex sulfide ore, and its formation was counteracted by diethylenetriamine (DETA). The FTIR spectrum of the pulp solid fraction showed varying degrees of oxidized surface species, which are related to the concentration of H2O2 analyzed in pulp liquid. Bench-scale flotation using two different complex sulfide ores showed that sphalerite recovery is better in process water than in tap water. Flotation results also indicated a varied recovery of sphalerite at different temperatures in either tap water or process water.
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