However fine particle flotation may remain as the main focus of re processing tailings dams Keywords Flotation cells; fine and coarse particles; technological development; flotation kinetics; HydroFloatTM cells 1 Introduction Froth flotation was undoubtedly the most innovative and mining saver in ore dressing in the 19th century [1]
The sequential multi scale method is then illustrated with reference to the mineral flotation process In this case multi phase CFD computational fluid dynamics models of large scale cells has been complemented by micro scale CFD simulations of bubble particle collision and experimental and modelling studies of the bubble particle attachment process itself
Mineral carrying rates across the pulp froth interface in the range of tph/m 2 and bubble surface coverage between 7 and 22 % have been determined in large rougher flotation cells 100
Table 1 shows the main copper minerals found in nature [40 53 54 55] mineral association as well as the type and design of flotation cells and operating variables such as pH air flowrate pulp density reagent type and dosage Therefore several authors have investigated methods to increase the efficiency of flotation processes
Mechanical column and pneumatic flotation cells Jameson Imhoflot TM and Reflux TM flotation cells ; Impact of operation parameters on designing flotation cells gas hold up superficial gas velocity bubble size distribution and orifice type etc ; Measurement and modelling of slurry residence time in flotation cell/circuits Dr Fardis
The effect of hydrophobicity on the drainage of gangue minerals in flotation froths Minerals Engineering vol 17 pp 897 901 [ Links ] Ata S and Jameson 2005 The formation of bubble clusters in flotation cells International Journal of Mineral Processing vol 76
Fig 5 illustrates that the recovery of the colored minerals in the microflotation cell using BD 15 flotation is 78% under alkali conditions pH 9 while G TAP flotation recovery for albite is 85% in acidic conditions pH 3 The experiments carried out using G TAP reveals that the increase in pH leads to a dramatic decrease in
Flotation experiments For flotation studies the samples were ground and then sieved to collect the − 150 to 75 μm fractions for the microflotation mineral microflotation tests were performed in a 300 ml Hallimond tube at a constant rate of number of experiments were carried out using varying levels of pH and reagent concentrations
For example in the AMIRA P780A project flotation cells up to 150 m 3 from Outokumpu and Metso Minerals have been investigated to improve flotation performance Koh et al 2003 In the present paper the effect of impeller speed on the air flow in a self aerated Denver laboratory flotation cell was investigated using CFD modelling Koh et
Entrainment is a process by which fine and ultrafine particles are transferred to the flotation froth from the top of the flotation pulp and eventually discharge to the concentrate product even when they are not attached to gas bubbles Therefore entrainment can be considered as a two step process one at the upper layer of the pulp to the flotation froth and
The Imhoflot G Cell was invented by Dr Rainer Imhof of Maelgwyn Mineral Services Ltd MMS based in Cardiff Wales The G Cell is a new addition to the family of pneumatic flotation technologies developed and commer cialized in the last few decades The term pneumatic flotation is generally accepted as defining flotation systems where
Flotation is an important process in the minerals industry and most flotation is carried out using mechanically agitated cells ranging in volume up to 300 m of the particles of valuable minerals from the ore is achieved when particles of the valuable minerals preferentially attach to air bubbles and are floated to the surface of the slurry via a froth layer
In recent years microbubble flotation technology has been widely applied to industrial scale separation and treatment of various mineral components Ananthapadmanabhan and Somasundaran 1985
Separating minerals in a froth flotation cell has a particularly corrosive effect on a slowly rotating rake and its components Mixtures of slurry surfactant water air and froth can quickly lead to failed seals and bearings Which of course means costly unplanned downtime and lost productivity
Processing of minerals and metals involves carrying out the functions of mixing reaction and separation in order to separate valuable components and render them in a form suitable for further processing Wills 2006 In addition multiphase interactions such as breakage or agglomeration of particles and break up or coalescence of droplets and bubbles usually play
easily activate zinc sulfide minerals while residual chemicals can decrease the flotation recoveries Sandenbergh and Yei 2007 In Yenial and Bulut 2014 the ion concentration of the recycled water was found to be indicative for enhancing flotation recovery because very high amounts of ions could decrease recoveries
The modelling methodology was first validated by modelling a simple impeller driven stirred tank as used in both experimental and numerical studies by Adams and Barigou 2007 This consisted of a tank with T = 148 mm with four baffles of width T and agitated by a 6 bladed 45 ° down pumping pitch blade turbine PBT The diameter of the impeller D = T / 3
Make up water used in the tests was Brisbane tap water After the ground slurry P 80 of 90 µm was transferred to the flotation cell The formation of hydrophilic OH − ion and reduced potential consequently depress the sulphide minerals flotation −660 to 1070 mV SHE and that the main oxidation product found on the mineral
The mass flowrate of particles ton/h entering the froth by true flotation was evaluated from direct measurement of bubble load ton/m 3 and gas flowrate m 3 /h This information together with the concentrate mass flowrate allowed the estimation of the froth recovery of floatable mineral in a 130 m 3 rougher flotation It was found that mineral
