IPCC TECHNOLOGY
One of two recently completed MMD Semi- Mobile Sizing Stations at the Xilinhe Coal Chemical mine in China ' s northeast Inner Mongolia Autonomous Region
many others . Through improved tooth , shaft and drive train developments , MMD Sizers can now break through hard and abrasive materials up to 400 MPa , whilst continuing to deliver the unique benefits , productivity and efficiency associated with Sizing and Conveying ."
Tailings and materials handling
Terra Nova Technologies Australia Pty Ltd ( TNT Australia ) and sister company e2o , Clough ’ s global asset services company , have recently been awarded a replacement tailings stacker contract by Karara Mining Ltd at their Magnetite Mine located 200 km south-east of Geraldton in Western Australia . Karara is the largest mining operation and the first major magnetite mine in the Australian mid-West . It produces a premium , high-grade concentrate product for export to steelmakers with an expected mine life in excess of 30 years .
The scope of supply will be to replace an existing stacker . The contract will include the supply of a new “ fit for purpose ” heavy duty stacker able to withstand the rigours of a highcapacity mining environment along with the associated civil works , installation , commissioning , and removal of the existing stacker . This contract will be completed by TNT Australia and e2o , working in partnership as part of the Murray & Roberts group . The replacement stacker project , which commenced in January 2022 , is required to be concluded within the existing calendar year in order to meet Karara ’ s schedule requirements .
Super Portable ® ramp conveyor from Terra Nova Technologies
Elsewhere , the TyV consortium , comprising Terra Nova Technologies ( TNT ) and Vial and Vives DSD , has been awarded another EPC contract for a major mining client in Chile in January 2022 . The brownfields expansion project includes the supply of a new Ripios re-handling system comprising a materials handling solution which includes belt feeders and in-plant conveyors complete with electrical room and all control systems . The EPC scope includes the MSE wall , all earthworks and access roads , as well as the modifications and tie-ins to existing plant and infrastructure which will be completed within two years . The TyV team successfully completed a large EPC work package last year that included a Primary Crushing Station , Sacrificial Conveyor and Overland Conveyor System inclusive of all auxiliary equipment for the system .
Terra Nova Technologies ( TNT ) in addition has received construction contracts for the assembly , installation and commissioning of the recently TNT supplied 6,000 t / h proprietary Super Portable ® ramp conveyors and a secondary Super Portable ® Stacking equipment at a large copper mine in Arizona in the US . The award effectively integrates the design supply and construction scopes into an EPC project . The new Ramp Super Portable ® equipment , and the fully mobile stacking equipment comprises a Horizontal Feed Conveyor , Horizontal Conveyor and Radial Stacker and will supplement the existing Heap Leach Stacking system supplied by TNT in 2014 . This equipment will be utilised to effectively create a secondary redundant stacking system that will increase the overall system availability , utilization and increase daily throughput significantly .
This is a similar technique used at other large copper mines , in that the stacking equipment can be set up on the next cell ready to go once the prior cell ( stacking area ) is complete . This eliminates the downtime whilst the stacking equipment moves between cells and systems with this configuration operate with high ninety percentile for availability . Super Portable ® fully mobile conveyors can overcome this valid concern , in that if any one of the chain of mobile conveyors has an unscheduled breakdown , it is simply removed and replaced in a similar fashion to trucks . In normal operation , a mobile conveyor is added in for advancing or removed in a retreat mode . Similar 10,000 t / h systems , operating in large copper heap leach systems , have proven to have high reliability and usually a few spare machines are also kept on hand to replace operating units in the event of an
unexpected breakdown , hence the addition of the few extra Ramp Super Portable ® conveyors to further supplement this existing system . This configuration requires only a few pieces of additional mobile stacking equipment to add high availability and flexibility to complex valley fill waste stacking , dry tails stacking or permanent pad multi-lift heap leach systems .
Green conveyor systems driven by slow-speed gearless drives
Petr Kunz of Czech group Prodeco a . s . and ABB ’ s Ulf Richter explained to IM how a new ‘ green ’ conveyor system featuring ABB slow-speed gearless drives is helping an operator in the Czech Republic reduce both noise and dust pollution , and its CO 2 footprint , while maintaining the efficiency of materials handling operations . Noise pollution , energy consumption and emissions of dust particles are three of the main challenges faced by mine operators as they look to optimise ore throughput , production and revenues , while also ensuring their operations comply with stringent local and global environmental legislation .
Conveyor systems are responsible for almost 80 % of the energy consumption in mines , equating to many tonnes of CO 2 emissions over the lifetime . Material on conveyors may cover distances of tens of kilometres and ascend steep gradients . To increase overall reliability , mine operators want fewer transfer stations between conveyors , which may in turn require wider and longer belts .
Richter comments : “ The gearbox is an integral part of the drive system ; if it fails , the system will be down for a considerable time . For this reason , low-speed gearless conveyor drives ( GCD ) are increasingly becoming the solution of choice for mining projects – particularly those that require high drive power . GCDs enable and help to boost the efficiency of high-capacity belt systems , while reducing energy usage , downtime and maintenance . Gearboxes that are able to handle powers in excess of 3.5 MW are maintenanceintensive and their productive lifetime is relatively short . ABB has addressed this issue by replacing the gearbox with robust , reliable control from variable speed drives running accurately performing , low-speed motors .”
In this set-up , permanent magnet motors can produce the same torque power with 20-25 % less motor current , thus reducing the size of frequency converters and motor feed cables . Because of their compactness they reach similar sizes as geared drives and so can replace them . Also , the number of motors needed on the drive system by combining the power demand in one permanent magnet motor can be reduced , resulting in less maintenance and energy consumption .
44 International Mining | APRIL 2022