MINING CHEMICALS
dosages that Maelgwyn hopes will unlock economic and environmental benefits for their respective clients .
The Imhoflot high shear environment disperses reagents into a turbulent zone to aid homogeneous dispersion , decreasing the time and dosing required to condition the entire pulp volume . This leads to operating cost savings and a smaller plant , Maelgywn says .
“ The nucleation of nano-bubbles in the pulp and at the mineral surface enhances the bubbleparticle attachment physics by lowering the interfacial free energy ,” Maelgwyn explained . “ In effect , the nucleating bubbles act as a ‘ secondary collector ’, reducing the dosage of flotation reagent required .”
Maelgwyn says it has found evidence that , in some flotation systems , the small bubbles act as carriers of the collector to the mineral surface from the pulp , which further increases the kinetics of flotation .
Fine recoveries The Imhoflot G-cell is applicable for a range of particle sizes from ultra-fine ( -20 μm ) to intermediate-sized particles ( 50 μm ).
The G-cell uses a “ unique ” dynamic centrifugal motion to promote gangue disengagement from mineral-bubble agglomerates within the pulp before gently spinning the concentrate froth to reduce gangue
BIOMINING ’ 21
7-9 June , 2021 | Online
Sponsored by : AFX Mixing & Pumping Technologies , Newmont , International Mining , Ocean Mining Intel , Cornwall Mining Alliance & Critical Minerals Association
SUSTAINABLE MINERALS ‘ 21
21-23 June | Online
Sponsored by : FLSmidth , International Mining , Cornwall Mining Alliance , CEEC & Critical Minerals Association
FLOTATION ’ 21
8-11 November , 2021 | Hybrid or Online
Sponsored by : Promet101 , Maelgwyn Mineral Services , Magotteaux- Gold Ore , CiDRA Minerals Processing , Hudbay Minerals , Senmin , Clariant , BASF , Eriez , Nouryon , Festo , International Mining & Critical Minerals Association
PHYSICAL SEPARATION ‘ 22
June 2022 | Falmouth , UK
Sponsored by : CEEC , International Mining , Imformed , Cornwall Mining Alliance & Critical Minerals Association
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entrainment by both keeping the pulp-froth interface turbulence low and allowing gangue entrained in froth bubble interface water to drain away from the central concentrate launder by centrifugal force .
“ It is this combination of factors which , when combined with a selective reagent scheme from a team such as Axis House , allow the G-cell to achieve superior concentrate grades ,” Maelgwyn claimed . “ The G-cell often finds application in challenging cleaning duties or recovery of ultrafine particles ( down to 5 μm ) where columns are struggling to achieve the recovery required .”
Imhoflot cells can be supplied in modular forms to achieve specific test work tasks before installation of a full-sized cell or combined to provide a cost-efficient retrofit to existing plants .
For instance , the application of a three-stage G-Cell at a nickel plant in Europe demonstrated Imhoflot ’ s ability to recover an additional 30 % of nickel from the final tailings , predominantly in the -11 μm size fraction .
At another operation – this time zinc – a twostage Imhoflot G-Cell plant was used to avoid losing metal in the -7 μm mineral particle category . In this operation , the G-cell recovered an additional 20 % of the zinc from the final cleaner tailings .
Imhoflot is currently being trailed at one of the biggest gold concentrators in the CIS region where the existing conventional cells were not achieving the desired grade-recovery profile with the main gold losses reported to be in the fine ( -38 μm ) and ultra-fine ( -20 μm ) size fractions .
The application of two pilot G-14 cells in open circuit demonstrated the ability to recover the fine and ultra-fine gold loss to the tailings , with the G-cell achieving an average concentrate grade of 19.94 g / t with an addition of plus-40 % gold recovery from the tailings . Size-by-size analyses from the same gold operation showed it was possible to achieve an additional recovery of 65 % and 68 % in the size fractions of 0-20 μm and 20-38 μm , respectively .
Tailings treatment
Reacting to the critical need to reduce waste in tailing ponds and maximise recovery of valuable minerals , Clariant , in 2020 , launched a suite of new tailing flotation products for the treatment of slimes .
The solutions , which included those from the FLOTIGAM™ and FLOTINOR ™ range , are geared towards improving iron ore recovery .
FLOTIGAM 7500 is a sustainable flotation collector for the removal of quartz and other silicate minerals from iron ore . Based on its new technology , a more selective adsorption at these gangue minerals ’ surface is achieved , providing improved flotation performance in terms of iron recovery and concentrate grades , according to Clariant . It is a robust product that can sustain plant variations and keep operational targets under control , also allowing the production of iron concentrate within market specification with a better cost-benefit outcome than other industry solutions .
FLOTINOR 5530 , meanwhile , is a collector developed for iron ore slimes flotation .
Typically , the iron ore concentration process requires the step of desliming to remove ultrafine particles that damage conventional flotation performance . However , at this fraction , there are still high contents of valuable iron minerals that , in most processes , are sent to the tailings dam as waste material , Clariant says .
This slimes fraction , instead of being disposed at the tailings dam , can pass through a flotation step . Gangue minerals , mainly quartz and kaolinite , are floated and the iron mineral , mainly hematite and goethite , are kept in the concentrate , thus presenting as a commercial product , Clariant explained .
FLOTINOR 5530 presents not only economical benefits that come with increasing the overall iron recovery at the processing plant ; it also has environmental benefits by reducing the amount of tailings generated by an iron ore processing plant , the company said .
Alongside these iron-related innovations , two HOSTAFLOT™ products were advanced by Clariant in 2020 .
These xanthate replacement technologies provide mining operators with a safer and more sustainable alternative to xanthate collectors , allowing mining operators to discontinue the use of xanthates , which can come with fire and explosion hazard risks .
These alternatives , which Clariant developed through collaboration , offer a high copper flotation performance , safer handling and disposal , reduced capital expenditure and a longer shelf life than xanthates , according to the company .
IM
56 International Mining | MAY 2021