IPCC TECHNOLOGY
While the upside of IPCC as a mining approach has not fundamentally changed – reduced or eliminated diesel truck fleet , high throughputs , electric and autonomous operation – the reasons for doing it have certainly had a boost as the mining industry has made firm Scope 1 emissions reduction targets . To some extent , that has removed concerns about initial cost , given that miners face very uncertain costs anyway if they were to switch to battery electric haul trucks and associated charging infrastructure , much of which remains an unknown quantity . Even to go with trolley assist , whether with diesel-electric or all electric trucks , represents a big spend on trolley infrastructure .
IM spoke at length to Rico Neumann , TAKRAF ’ s Chief Mine Planning Engineer , about the big picture of IPCC options . First of all , he emphasised that each alternative of mobile , semi-mobile or fixed crushing plant still has a justification of existence , “ depending on the given project conditions , design criteria and a feasible project cost model over a given deployment period .” He adds : “ Flexibility costs - and every customer has to decide how to manage not only the obviously most effective alternative but also being prepared for future developments such as pit modifications , technical improvements , cost developments and even stricter approval and environmental laws .”
He also pointed out that some pits that are more hazardous from a geotechnical point of view meaning the mining company often does not want to invest in IPCC equipment within the pit and would prefer to have a fixed station on the pit edge – and the same for pits with the potential to be advanced in all directions .
One of four thyssenkrupp semimobile crushing stations at the First Quantum Minerals Sentinel copper mine in Zambia
Green mining with IPCC
With mining companies looking for a route to net zero , in-pit crushing & conveying offers one of the most proven ways to get there , reports Paul Moore
Semi-mobile crushing stations are in many ways an ideal compromise between flexibility in the pit and the requested improvement of the carbon footprint by reducing truck haulage following pit advance . These stations are of modular design and have now been implemented for decades , designed from the outset to be relocated in transportable pieces . “ Some modules are from the shelf just modified to the required capacity like dump hoppers , feeders and discharge conveyors , while other modules have to be designed to the special project design criteria , for example the civil construction and the base frame according to earthquake zones and the crushing machine itself considering rock properties , ROM and product size .”
Neumann says that TAKRAF has improved the modular design over the years by means of construction – parts preassembled to the construction site being as big as possible , more bolted connections and a more open design of base girders .
The dream of replacing almost all fuel consuming truck hauling out of a pit with fully mobile crushing units will work just in a very few suitable operations . “ Bench conveyors or a bunch of mobile conveyors in a line , required ramp conveyors out of the pit , maintenance access and maneuvering areas require space and safety distances to slopes and working faces to be blasted . That space has to be bought in most cases with additional waste wedges in the pit shell . Special solutions such as conveying with steep angles will help , but these then becomes some of the
most sophisticated conveying solutions regarding selected location , technical solutions and maintainability especially for high capacities . Generally the mine plan , as well as the working scheme for the fully mobile crushing and conveying system , has to be planned properly .”
On maintenance , Neumann said that TAKRAF always delivers a detailed maintenance schedule based on its vast experience from the many crushing and conveying projects it has delivered and then adapts it to fit into or improve the customers ’ overall maintenance strategy . “ For certain areas like conveyor transfer points and moving parts of equipment and their control devices like slewing connections , roller tables and travel units , a preventive maintenance regime is absolutely required to detect irregularities and minor damage to avoid larger failures and downtime .”
TAKRAF , some years ago , developed dedicated conveyor maintenance carts , of which it has three units installed , which improve the safety and effectiveness of both regular and preventive maintenance for long and inclined conveyors in areas not accessible ( or difficult to access ) by a maintenance truck . These carts can conduct remote checks of idler temperatures , for example . In some cases as part of aftersales service , TAKRAF supports customers with a representative at site , connected to TAKRAF ’ s service department and contactable 24 / 7 for anything related to operation and maintenance .
On the zero emissions question , he adds : “ The reduction of fuel burning truck fleets is central to improving the carbon footprints of today ’ s mining operations . Only with detailed studies implemented at the very beginning , can the possibility of IPCC system applications provide an answer on how an optimal and effective mining system can be for the specific project requirements . TAKRAF , with its triangle of Equipment Knowledge , Mining Expertise and Operational Know-How , is able to contribute with fast , cost effective and high accuracy studies or study support . At the end of the day , truckless
TAKRAF conveyor maintenance cart at Codelco Chuquicamata
40 International Mining | APRIL 2022