COPPER PROCESSING
FLSmidth says its HPGR Pro enables up to 20 % more throughput compared to conventional HPGRs , with less energy consumption and up to 30 % longer roller life the life of the mine .”
And Douglas claims this pathway can be taken without impacting a company ’ s position on the cost curve .
“ This can be translated into measured values of lowering the CO 2 / tonne and water / tonne of metal produced , while maintaining a competitive cost / tonne in operating expenses ,” he concluded .
Jesús Pelayo , VP Global Key Accounts – Copper at FLSmidth , told IM that the company sees a significant business opportunity in bringing its copper customers towards a sustainable future , highlighting several developments , including in the comminution space .
“ With our most recent acquisition , FLSmidth is stepping into the spotlight as the market leader in high pressure grinding roll ( HPGR ) technology ; our HPGR Pro offers better performance and much lower production costs , meeting the highest demands for economy , efficiency and reliability ,” he said . “ Over the entire lifecycle , this new development enables up to 20 % more throughput compared to conventional HPGRs , with less energy consumption and up to 30 % longer roller life , supporting our clients in reducing their GHG footprint .”
On the tailings management side – an area highlighted by The Copper Mark in terms of ongoing assurance framework developments – Pelayo highlighted the company ’ s EcoTails ® process , which , he says , makes it possible to recycle more than 90 % of water associated with tailings management .
“ This represents a great opportunity for our clients to achieve not only zero GHG emissions but zero water discharge and zero energy waste ,” he said .
The company ’ s REFLUX™ Flotation Cell ( RFC™ ) technology , meanwhile , pushes the boundaries on concentrate grade , recovery and throughput well beyond the performance of conventional open tank flotation systems , reducing GHG emissions in the process , according to Pelayo .
He added : “ Demand for minerals is rising – that ’ s the good news – but mining is also getting harder , while pressure is on to improve the industry ’ s environmental , social and governance ( ESG ) performance . In response , mines must take steps to maximise productivity and realise their
full potential via systematic and ongoing performance optimisation . This is where we come in ; to identify opportunities to improve productivity across the flowsheet , plan and implement upgrades to achieve best outcomes for investments , and monitor and measure results to empower continuous improvement processes .”
FLSmidth is backing up these technologies with targets such as reducing GHG emissions coming from the use of its products per unit of revenue by 56 % by 2030 , compared with its 2019 baseline . This target , validated by the Science Based Targets Initiative , corresponds to a 7 % year-on-year drop in emissions .
Wayne Douglas , Head of Technology , Innovation and the Mineral Technology Research Centre , says FLSmidth ’ s ‘ Concentrator Of The Future ’ will steer the company towards this goal and end up as the benchmark in minerals processing in the future , providing disruptive innovations along the whole flowsheet in dry comminution , coarse and fine flotation , and dry tailings linked by digitalisation and artificial intelligence ( AI ).
“ Our strength in combining our products in unique combinations to maximise the sustainability desires of the client will allow us to optimise for any challenge ; be it water , energy efficiency , grade , recovery , footprint , etc ,” he said . “ This can be accomplished with existing products , or by innovations in processing as outlined by the MissionZero mine .
“ On top of the individual product ’ s performance at purchase , we focus on the full lifecycle of the products across the plant to deliver continued best-in-class performance , uptime and total cost of ownership . With appropriate spares , performance-enhancing digital solutions , advanced wear parts and recycling of components where possible , we can ensure the lowest environmental impact during
Redefining the mill circuit
Bjorn Dierx , Enduron HPGR Global Product Manager for Weir Minerals , agrees with Pelayo ’ s assessment of the copper producing environment becoming more complex and challenging in recent years .
In response , he says Weir Minerals is harnessing digital and technological opportunities to redefine one of the most energy intensive parts of the mine – the mill circuit .
Traditional mill circuit flowsheets – comprising SAG mills and ball mills – are inefficient , with 40- 60 % of the slurry returned to the mill for reprocessing , according to Dierx , reducing the throughput and capacity of the mill .
“ Water is also lost through evaporation with each pass ,” he told IM . “ As the grinding media composition needs to be balanced against the rock fragmentation and comminution characteristics , it is also relatively inflexible in responding to changing feed conditions in an agile way .”
The redesigned and reconfigured mill circuit Weir Minerals envisages sees the SAG mill replaced by a more efficient HPGR that is also less energy intensive and able to reduce recirculating loads threefold , according to Dierx .
“ It is able to swiftly change the required grinding parameters , producing a more predictable output , even with changing feeding conditions ,” he explained .
In this redesigned comminution circuit , the ball mill will be replaced by a vertical stirred grinding mill , which Weir Minerals now offers its customers through its recently announced alliance with Swiss Tower Mills Minerals .
Integrating vertical stirred grinding mills into Weir Minerals ’ minerals processing flowsheet will provide customers substantial improvements in throughput and energy efficiency , helping them meet their productivity and sustainability goals , according to the company .
Dierx continued : “ The reconfigured flowsheet reduces overgrinding and applies energy mainly to the coarser particles , resulting in a steeper particle size distribution ( PSD ), which , in turn , improves mineral recovery during flotation .”
When the mineral is able to be liberated at a coarser size fraction , additional efficiency gains can be achieved by introducing coarse particle flotation ( CPF ).
14 International Mining | MARCH 2023