CHASING THE GREEN PREMIUM digital capability through the Weir Synertrex ® platform , we will be better positioned to get these numbers and report accordingly .”
With the accelerating roll out of Weir ’ s digital capability through the Weir Synertrex platform , the company should be better positioned to generate and report Scope 4 avoided emissions calculations , according to Stephen Marshall
processing efficiency can have a significant impact on footprint ,” he said . “ Such efficiency gains are driven by a combination of technological innovation – for example , the increasing use of electric vehicles for loading and haulage and digital intelligence capability that is becoming essential to mining operations .
“ On the other hand , energy sourcing is also critical , and miners are increasingly turning to
wind , solar and , where possible , hydroelectric power sources .
“ Realistically , it is a combination of these processing efficiency and energy-sourcing factors that will deliver green advancements in mining ; and that trend is only going to grow .
“ I like to think that in the not-too-distant future , we will see a miner labelling itself as ‘ green ’.”
When it comes to breaking down the Scope 4 emissions categorisation Weir hopes to benefit from , Marshall highlighted a need to convey the potential productivity benefits at the same time . This , he said , would allow ‘ buy in ’ from all levels of mining company management – at site and corporate level .
“ In Weir , we recognise that different teams in the mining supply chain will have subtly different priorities ,” he explained . “ The operational team will be focused on productivity and for them it makes sense to link packaged solutions to productivity . Of course , productivity is important to the C-Suite as well , however they will tend to have the additional driver of emission reductions in their operations .
“ In general terms , productivity and efficiency gains can be linked directly to Scope 4 avoided emissions because better efficiency generally means less energy to achieve the same result .”
What Weir is working towards is providing a set of tools with realistic measures that allow it to report both productivity gains and Scope 4 avoided emissions as part of its solution .
“ This will enable us to provide the necessary focus on what the solution needs to deliver for the customer , depending on their priorities ,” Marshall said . “ In this sense , Scope 4 estimates will become part of our value proposition .”
In terms of where the company sees the greatest initial opportunity to bring down Scope 4 emissions in the mill and flotation circuits , Marshall immediately highlighted Weir Minerals ’ Enduron ® High Pressure Grinding Roll ( HPGR ) technology as an example .
This solution can process the same quantity of ore at 30-40 % less energy compared with the industry-standard SAG mill , according to the company .
“ Considering the volumes of ore processed globally , the potential for HPGR technology alone to reduce our carbon footprint is enormous ,” Marshall said .
Adding to that capability the technology available through partnerships with Eriez and Swiss Tower Mills Minerals ( STM ), the company sees the potential for even more gains through creation of an entirely new processing flowsheet for the industry .
“ The Eriez Coarse Particle Flotation ( CPF ) technology has benefits in a further reduction in the grinding energy required , increased value recovery and easier tailings dewatering ,” Marshall said . “ The STM stirred mills are known to be highly efficient solutions to replace ball mills as well .”
Taken together , this technology mix of HPGR , CPF and stirred mills has the potential to make a very “ significant impact ” on carbon footprint reduction , he added . “ We are working closely with our partners to make this real for our customers .”
And Marshall sees the possibility of Weir recording “ green revenue ” tied to Scope 4 emissions avoidance within the next two years .
He concluded : “ We still need to overcome challenges in obtaining accurate operational measurements , including baselining current operations ; and that will take some time . However , with the accelerating roll out of our
SRK talks emission reduction options
David Pearce of SRK Consulting takes Marshall ’ s observation about the current ‘ green ’ credentials of the mining sector further , acknowledging that mining is currently responsible for 4-7 % of GHG emissions globally .
“ Scope 1 and Scope 2 CO 2 emissions from the sector , those incurred through mining operations and power consumption , respectively , amount to 1 %, and fugitive-methane emissions from coal mining are estimated at 3-6 %,” he added .
The significant level of these emissions reflects the potential for mining to create a positive legacy , he says , with many of the world ’ s major miners having already set demanding targets for themselves .
This transformation will require mining companies to continue to reach out to industry to proactively find relevant and sustainable paths to decarbonisation , identifying suitable solutions and designing the operation around these requirements . This , Pearce says , will need both innovative thinking and extensive experience in mining operations .
Pearce , Principal Mining Engineer at SRK , and his colleagues have already witnessed this , with several remote mines looking to decarbonise their power inputs by commissioning a combination of solar and wind power systems with battery capacity to extend renewable energy utilisation as much as possible .
“ Some mines in Australia are generating up to 60 % of their power from renewable sources and are looking to increase this to circa-80 % through adding additional renewable capacity ,” he said .
Of course , electrifying mine truck haulage systems is another potential strategy to decarbonise operations as haulage can represent between 30-50 % of emissions .
“ Each large truck in an open-pit application typically consumes 800,000 litres to 1 million litres of diesel a year , translating to between 2,200 and 3,000 t of carbon dioxide ,” he said .
On the available technologies to rationalise this diesel use , he picks out trolley assist and inpit crushing and conveying systems as potential technology avenues . These suggestions are in line with the pipeline of projects the major mining companies are pursuing to achieve their 2030 , 2040 and 2050 emission targets .
“ These can reduce diesel consumption by 60- 80 %,” Pearce said of these systems . “ However , implementing such solutions requires changing mine designs and plans . This is where SRK can provide the necessary insights , advice and designs – to ensure that any technological changes will be suitable and effective .”
42 International Mining | APRIL 2023