FLOTATION applied in a particle size range from a p80 of 350 microns to 850 microns in metallic sulphide minerals but some industrial minerals processes can see particle sizes of 1 mm or more . He adds : “ In essence CoarseAir is effectively a REFLUX classifier that is utilising an aerated fluidisation system . You can look at it as a hybrid between a teeter bed separator and a flotation cell , combining a dense bed with the application of air . It includes lamella plates for much more efficient separation as well as the ability to operate with a higher degree of fines than other coarse particle flotation options in the market . Finally compared to open tank style teeter bed separators , CoarseAir offers a much sharper cut and a higher throughput by area . The testwork we have done shows we are able to take cyclone underflow material of the appropriate size distribution and feed that straight to the CoarseAir and achieve adequate recoveries and grade .”
CoarseAir is one element of what FLSmidth calls its REFLEX technology suite – which also includes the REFLUX Classifier , The REFLUX™ Flotation Cell ( RFC™ ) combines several technological elements to achieve superior performance in maximising recovery , gas flux , bubble-liquid segregation and product cleaning . CoarseAir as the name suggests goes after coarse particles ; then the RFC is a high efficiency flotation machine – “ the recovery curve is shifted , allowing production of high grade concentrate at high recoveries , while also reducing substantially the required flotation volume – five or even seven times less . And while the RFC would currently be aimed at smaller footprint cleaning circuits and scavenging applications , the technology is still suitable for large scale roughing – but of course it is a new technology so we are taking things gradually to minimise risk .”
Sustainability is also front and centre for FLSmidth , so what does the flotation part of the flowsheet of the future look like in the MissionZero mine ? “ CoarseAir will allow an increase in the grind size , with the RFC handling reground coarse material and any fine material present . That all means lower water usage plus reduced power due to not requiring a finer grind . It also means lower tailings volumes and less metals lost in the tailings ,” said Christodoulou . He added CoarseAir is at a site trials stage using a pilot machine .
The RFC he said is undergoing a full scale trial in Australia at a coal operation . “ Initial results show that the scale up from pilot scale is going exactly as predicted with flow rates twice that of conventional flotation systems .” Then looking at metals recovery there is the RFC upscaling project , supported by EIT RawMaterials with EU co-funding . The project goal is to demonstrate the superior performance of the RFC for copper
and iron ore . This is an important intermediate step to the full commercialisation of the technology via consortium partners and FLSmidth .
During the project , FLSmidth says it will create and validate a profound Go-To-Market strategy including financial planning and business model developments . Phase 1 is complete , which saw feasibility studies with the RFC-100 pilot plant to narrow down design options , then engineering and assembly of the RFC-850 demo plant . Pilot work has been completed with two mining partners , copper miner KGHM in Poland , and iron ore miner LKAB in Sweden – now full size RFC- 850s have also been installed at those sites for full scale trials .
Back to the overall market – how important is retrofit versus greenfield ? For the new technologies most of the initial installs are likely to be retrofits or tailings related but as the technology becomes accepted , more of them will enter the greenfield market . Christodoulou : “ The appetite for new technologies is much greater now than even a decade ago as miners seek to maximise recoveries as well as achieve sustainability targets .”
This increase in interest is manifesting itself in much more piloting and testing – and FLSmidth is well set up for this . It has three containerised RFC pilot units that are available for site trials ; in addition to a lab pilot unit . There is also a
out of tradition - It pays to talk to a specialist !
����������������������������������������������������������������������������������������
DELKOR BQR flotation cell with MAXGen mechanism
Superior metallurgical performance and increased metal recovery at lower cost of ownership Improved particle-bubble interaction , faster flotation kinetics and precise froth level controls Cell bypass ready provision for improved flexibility and ease of maintenance Available in sizes from 1.5 m ³ ( BQR15 ) to 300 m ³ ( BQR3000 )
info @ takraf . com www . takraf . com
For more information about our BQR flotation cells please scan the QR-code .