IM 2022 October 22 | Page 6

WORLD PROSPECTS

TOMRA ore sorters open up Mt Carbine opportunities

TOMRA X-Ray Transmission ( XRT ) sorters are providing a game-changing solution for the EQ Resources-owned Mt Carbine mine in Queensland , Australia , reducing costs and achieving high-purity tungsten ore for follow-on processing while contributing to a circular economy by producing green aggregates for sale , the ore sorting company says .

The Mt Carbine mine was acquired by EQ Resources in 2019 . The company entered a joint venture with Cronimet Group to set up tungsten extraction from the mine ’ s large waste dump and tailings .
EQ Resources management has a longstanding relationship with TOMRA , having used its sorters with success on a variety of projects since 2011 , TOMRA says . Based on this experience , the company turned to TOMRA once again for the Mt Carbine mine .
“ We were confident it would work , but we sent a small sample for testing to make sure ,” Kevin MacNeill , CEO of Mt Carbine mine , EQ Resources , said . “ The advantage of TOMRA ’ s sorters compared to others is in the image resolution : it is able to resolve the finer inclusions in the tungsten . This high resolution gives us better recovery and more control over the sorting process .”
Mt Carbine is currently mining the 12 Mt of
low-grade historical stockpiles . The ore is crushed and screened at 6 mm and 40 mm . Two
TOMRA XRT sorters are used to pre-concentrate the feed in the 6-40-mm-size range before processing in the wet plant . Approximately 10 % of the sorters ’ feed mass is ejected as product with a recovery of tungsten of well over 90 %. This means only 10 % of the mass is processed in the wet plant , dramatically cutting running costs , reducing the required size of the wet plant , as well as saving water and energy , TOMRA says .
MacNeill said : “ One of the best things about the TOMRA XRT is the cost savings to the operation . It costs approximately A $ 1.5 / t ($ 1.02 / t ) to sort and then it costs A $ 14 / t for wet processing : as we take out 90 % of the sortable fraction mass , we only have to process 10 % of the higher-grade concentrate and natural -6 mm material while maintaining recovery , so our cost benefit is obvious .
“ We couldn ’ t afford to run this waste dump if we had to crush everything to 6 mm and process it through the wet plant .”
EQ Resources is also taking advantage of the TOMRA XRT sorters to create an additional revenue stream from the waste material .
MacNeill explained : “ Normally you would grind the waste down to 6 mm and put it through the jigs , but , by putting it through the
TOMRA sorters , we are able to keep a whole range of aggregates on the coarser size fractions . The sorters remove any material containing acid-forming sulphides and the waste rock that comes out is incredibly clean .
“ Selling these green aggregates adds a significant portion to our business – about A $ 5 million a year – and that ’ s all because of the TOMRA sorters . In fact , we ’ ve probably paid for each machine from this revenue five times over .”
The TOMRA XRT sorters are delivering both environmental and business benefits to the Mt Carbine operation , to the satisfaction of MacNeill : “ They ’ re dry , they create no water usage , they require very little power compared to what we use in the processing plant , so it ’ s a real advantage to us to have these , and we ’ re looking at purchasing a third one in the near future .” www . tomra . com ; www . cronimet . de / en ; www . eqresources . com . au

Rio Tinto to pilot Volvo sustainable autonomous haulage solutions

Rio Tinto and Volvo Group have signed a

Memorandum of Understanding related to both the supply of responsibly sourced lowcarbon products and solutions and a collaboration on decarbonising Rio ’ s operations through piloting Volvo ’ s sustainable autonomous hauling solutions .
While the type of autonomous hauling solution to be trialled was not specified , Volvo Autonomous Solutions , the automation-focused business area within Volvo Group , and Rio Tinto confirmed to IM that it will be in an active mining operation rather than an on-road application , adding : “ What we can say at the moment is that the solution being developed will be implemented in Rio Tinto ’ s operations and we are currently working together to determine what type of trucking solution will be most suitable based on Rio Tinto ’ s needs .”
There are several options for what such a project could include . Within Volvo Autonomous Solutions is the TARA system , comprising a cabless , battery-electric and autonomous dumper – the current incarnation of which is the 15 t TA15 – and all the needed infrastructure to make the operations run safe and smoothly including charging stations , a control tower , connected cloud solutions designed to meet customer operation requirements , maintenance and repair support ,
and the practical operations set-up . The TA15 has already seen use by Harsco Environmental in Hofors , Sweden , with four autonomous dumpers transporting slag from the site to a landfill ; and by Holcim at Gabenchopf quarry in Siggenthal , Switzerland .
On scaling up the TA15 , Volvo Autonomous Solutions President Nils Jaeger previously told IM that its discussions with mining groups “ do involve consideration of other size classes and leveraging the platform further in that direction ” but emphasised the haulers can also be part of what it calls a “ swarm concept ”, which means the mine can use many small machines in a very carefully coordinated way on the site rather than a small fleet of very large machines .
Volvo Group ’ s experience with tipper type trucks in mining includes at Brønnøy Kalk AS in Velfjord ,
Norway , where , since 2019 , six autonomous Volvo FH trucks have been transporting limestone from an open-pit mine about 5 km to a primary crusher .
Rio Tinto , for its part , has already stated that it is challenging its thinking on mining truck size and why size matters . “ Larger haul trucks , while already automated , consume more energy than current electric-vehicle power sources can generate . By exploring truck size , we want to assess how big and small trucks can both be a part of the solution to reduce our emissions in the Pilbara and find fit-for-purpose solutions in mining .” Work already includes an ongoing project with Scania XT 8 × 4 40 t tipper type trucks at the Channar iron ore operation .
Other reasons for looking at these types of smaller tipper trucks in the Pilbara instead of large rigids are thought to include more efficient transport of ore from more remote iron ore pits to crushing infrastructure at railheads ; as well as the fact that smaller automated trucks could more readily be electrified to reduce carbon emissions and could , therefore , improve zero emissions speed to market . www . riotinto . com ; www . volvogroup . com
4 International Mining | OCTOBER 2022