SHAFT SINKING demand for large diameter raisebore ventilation shafts to supplement ventilation requirements as production levels increase in some base metal mines .
“ This is helping to keep our fleet of large diameter raisebore machines like the Strata 950 , our most powerful raise drill , fully utilised ,” he concluded .
To mitigate challenges constructing a 140-m deep x 6.6-m internal diameter shaft in very poor ground conditions , Cementation Americas has developed a very innovative sinking methodology that does not require a full sinking headframe , which has saved the client in cost and has shortened the construction schedule , the company says
In 2022 , the companies established a memorandum of understanding that could see them collaborate on projects in Scandinavia going forward .
Patrick Hudd , Corporate Manager – International Cementation Canada , said the companies are still in the hopeful stages of securing joint work .
“ The raiseboring carried out by Orefields is unique from the methodologies by Cementation Americas ,” he explained . “ With this , we feel we are well placed to offer a wide scope to the regional European market with local knowledge , and international / North American contemporary expertise and engineering , as well as innovative partnering solutions for clients .”
He said the resurgent shaft industry throughout Europe , with many projects in the early planning stages , is an area of opportunity for which the companies are positively positioned with their joint skillsets and experience .
Like other peers in this field , Cementation is also exploring the use of battery-operated shaft equipment with various OEMs , with Ryan Payne , Vice President Assets Cementation Canada , saying such technology would help mitigate power impacts and reduce the noise impact to shaft workers .
He added : “ These technologies would potentially lessen the need for large power cables in the shaft and minimise the impact of large transformers and cable storage requirements needed on the stage . The resulting weight reduction subsequently cuts down the size of the equipment needed to suspend the stage .”
More immediately , Cementation is currently in a hoist commissioning phase at one of its shaft projects in Canada , where it is supporting taking two single drum hoists and electrically coupling them together .
“ Once integrated , the unit will shave off the peaks in power demand making them more energy efficient ,” Payne said . “ We also have the capacity to duplicate a similar outcome with some of our own hoist equipment in sinking operations where we can electrically couple the single drum hoists to support double drum operation .”
Kohtakangas , meanwhile , expected to see a future shift towards more shaft-supported projects in the precious metal sector where orebodies may extend at depth , and the existing method of ramp haulage to the surface no longer makes sense from economic and ESG points of view .
“ There will be pressure from mine investors in these scenarios to reduce carbon emissions and , therefore , it only makes sense to invest in new shaft infrastructure for all the right reasons ,” he said .
The other area where the company sees more shaft activity is in the rehabilitation space .
Kohtakangas explained : “ Many of the existing shafts sunk in the mid-1900s are getting old and worn , especially shafts in soft-rock mines like salt and potash . Additionally , some mines that have been put on care and maintenance , or even shut down , may be re-opened as the demand for minerals increases around the whole global electrification theme .”
These factors may require shaft dewatering and shaft rehabilitation , or possibly even new shafts , he added .
On top of this , Cementation is seeing a
UMS readying global expansion plans
United Mining Services Group continues to show off its ability to leverage high-end engineering skills , technologies and equipment to provide clients with project services ranging from concept and feasibility studies through to the detailed engineering and design , as well as construction management , construction contracting , commissioning and project ramp up .
It is currently engaged in two sinking projects located in Botswana and Brazil . This is on top of its recently completed “ hazardous waste ” project in the US where it sank a 7.92-m-diameter shaft to a depth of 693 m , plus carried out lateral development of 1,750 m .
In Botswana , UMS is helping Lucara Diamond Corp transition from open-pit mining to underground via a production shaft ( 765 m ) and ventilation shaft ( 731 m ). This scope includes raisebored material handling ore passes , level development of 1,550 m in total , level construction , production shaft equipping and permanent winder supply and installation .
Lucara reported in its June quarter results that the ventilation shaft had reached 550 m below collar , while the production shaft had reached 557 metres below collar . In the three-month period , the ventilation shaft sank 124 m and the 470-level station development commenced . The production shaft activities over the same timeframe included sinking a total of 108 m and completion of the 470-level station and development excavation .
In Brazil , UMS has been engaged by Ero Copper as part of the Pilar Deepening project . This project is designed to access deeper reserves of the Pilar mine , which has been operating for nearly 40 years , first as an open-pit mine and thereafter as an underground mine with ramp access .
The project includes a 6.3-m diameter vertical shaft that is 1,500-m deep , with permanent facilities to hoist rock ( ore and waste ) and raise / lower personnel to this underground level . The shaft is being sunk in a raisebore and slash method with follow-on shaft sidewall support
and concrete lining . This method will improve the rate of advance in shaft sinking , delivering the
commissioned shaft in quicker time , according to UMS .
The project is being executed by UMS through
110 International Mining | SEPTEMBER 2024