Tag Archives: Cadia

Newcrest leverages Eriez HydroFloat tech to help boost Cadia output

Having installed the first full-scale HydroFloat™ cells for the recovery of coarse composited copper and gold at Newcrest’s Cadia Valley operation in New South Wales, Australia, in 2018, Eriez is about to help the miner boost output at the operation.

Today, the Newcrest Board approved two projects moving to the execution phase, being Stage 2 of the Cadia Expansion project and the Lihir Front End Recovery project, in PNG.

The Stage 2 Cadia Expansion project primarily comprises the addition of a second coarse ore flotation circuit in Concentrator 1 (graphic above), using Eriez’s HydroFloat technology, and equipment upgrades in Concentrator 2.

These changes are expected to see plant capacity go from 33 Mt/y to 35 Mt/y, while life of mine gold and copper recoveries could increase by 3.5% and 2.7%, respectively. Alongside this, the company was expecting a A$22/oz ($16/oz) drop in its all-in sustaining costs.

An increase in throughput capacity in Concentrator 2 from 7 Mt/y to 9 Mt/y will be achieved through crushing, grinding, cyclone, pumps and flotation upgrades; while the installation of the second Coarse Ore Flotation circuit on Concentrator 1 and additional upgrades to Concentrator 1 will facilitate an increase in throughput capacity to up to 26 Mt/y, the company said.

“Stage 1, which is already in execution, was designed to maintain production continuity at Cadia through the development of PC2-3 (the next cave development) and increase the processing capacity to 33 Mt/y,” Newcrest said. “Stage 1 comprises an upgrade to the materials handling system and debottlenecking of the Concentrator 1 comminution circuit.”

The rate of ore mined from Cadia is expected to vary over time according to draw rates, cave maturity and cave interaction as further caves are developed, according to Newcrest. From the 2027 financial year onwards, life of mine Cadia mining rates are generally expected to be in the range of 33-35 Mt/y, with an average of 34 Mt/y used for financial evaluation purposes, the company said. Higher mine production rates may be possible, subject to further studies.

At throughput rates of 34 Mt/y, gold recovery improvements from Stages 1 and 2 are expected to achieve LOM gold recoveries of 80.3% and LOM copper recoveries of 85.2% compared to Stage 1 baselines of 76.8% for gold and 82.5% for copper.

The estimated capital cost for Stage 2 is A$175 million, A$5 million lower than the October 2019 estimate, according to Newcrest, which added that timing for delivery remains on schedule, with completion expected late in its 2022 financial year.

The Lihir Front End Recovery project, meanwhile, primarily comprises the installation of flash flotation and additional cyclone capacity, as well as cyclone efficiency upgrades, to improve grinding classification and reduce gold losses through the flotation circuits, Newcrest said.

The flash flotation and cyclone upgrades target the following process improvements:

  • Implement flash flotation to reduce mineral fines generated from overgrinding and send the higher-grade concentrate stream to the autoclaves; and
  • Improve cyclone efficiency to achieve a reduction in unliberated coarse mineral particles entering the cyclone overflow, which are not recovered in conventional flotation.

This is projected to result in LOM gold recoveries increasing by 1.2% and incremental LOM gold production increasing by 244,000 oz. It came with an estimated capital cost of A$61 million.

Newcrest to apply ‘unique technical capabilities’ to copper-gold mine in BC, Canada

Newcrest Mining has entered into an agreement to acquire a 70% joint venture interest in Imperial Metals’ Red Chris copper-gold mine and surrounding tenements in British Columbia, Canada, for $806.5 million.

The deal will see Newcrest become Red Chris operator, in charge of deciding how to exploit the copper-gold porphyry open-pit mine.

Newcrest said the acquisition of Red Chris was “a measured entry” into North America and aligned with its stated strategic goals of building a global portfolio of Tier 1 orebodies where Newcrest can “deliver value through application of its unique operating capabilities”.

Red Chris comes with a mineral resource of 20 Moz of gold and 5.9 Mt of copper. The acquired property comprises 23,142 ha of land with 77 mineral tenures, five of which are mining leases, and sits within the traditional territory of the Tahltan Nation.

Newcrest Managing Director and CEO, Sandeep Biswas, said: “We are delighted to add this asset into the Newcrest portfolio. Following due diligence, we believe we can bring our unique technical capabilities to unlock the full value potential of this orebody in one of the premier gold districts in the world.

“We have identified a clear pathway to potentially turn this orebody into a Tier 1 operation. The geology of Red Chris is similar to our Cadia orebodies in Australia and we will be applying our considerable experience in exploration, open-pit mining, caving and processing to maximise the value of Red Chris and the opportunities in the surrounding region. We look at this opportunity in the same way as we do with Cadia, where we have proven we can create significant value from deep underground porphyry orebodies.”

Following the intensive due diligence process Biswas mentioned, Newcrest said it has a two-stage plan to deliver value from the acquisition:

Stage one will see the company apply its “Edge transformation approach” to the existing Red Chris open-pit mine and processing plant.

“Newcrest believes it can add significant value to Red Chris by applying the same Edge mind-set and approach that has led to significant operating improvements across all Newcrest operations over the last five years,” the company said.

Examples of where successful changes have been implemented to safely accelerate cash maximisation include process plant optimisation (debottlenecking, recovery uplifts, process control, improving concentrate quality), mine optimisation (improving orebody knowledge, grade control, fleet management system, mine planning) and supply chain cost reduction, according to Newcrest.

As part of this stage, Newcrest said it will initiate an extensional drilling programme.

“Newcrest intends to optimise the current open-pit mine plan and pursue initiatives to improve operational productivities and milling recoveries,” Newcrest said.

The current open-pit mine has an existing 11 Mt/y processing plant and associated infrastructure which allows ‘brownfield’ expansion options in the future, it added.

Stage 2 will see the company apply “industry leading technology”.

The company said: “Newcrest believes it can add significant shareholder value by applying technology to Red Chris that it has successfully applied at its other operations.”

Examples include block caving – “Newcrest believes the orebody has the potential to become a high margin bulk underground block cave. Newcrest will accelerate the necessary drilling and studies. Newcrest intends to conduct studies and review the ore reserve of the Red Chris operation to allow for reporting in accordance with JORC 2012 to take into account the potential transition to a future block cave operation.”

Coarse ore flotation could also be considered, the company said.

“Having demonstrated the recovery benefits of coarse ore flotation at Cadia, Newcrest will look to apply this technology to Red Chris,” Newcrest said.

And, then there is the application of one of the most popular technologies today: ore sensing and sorting, of which Newcrest said: “Positive results from trials underway at Telfer may lead to this technology being deployed at Red Chris.”

In terms of exploration, Newcrest said it would apply its experience in deep underground brownfield and greenfield exploration on the existing orebody and the broader land package to potential uncover more tonnes of copper and ounces of gold.

“Newcrest has identified opportunities to expand Red Chris’s mineral resources along strike and at depth in areas where there has been limited deep drilling to date. Historical shallow drilling indicates that there is also potential for further deep discoveries to be made in the larger tenement package.

“Newcrest will be targeting prospective regions beyond the current mine looking for further porphyry centres including small footprint, higher-grade gold-rich porphyry systems leveraging knowledge gained from Cadia which has similar geological features,” Newcrest said.

Red Chris, on the northern edge of the Skeena Mountains, commenced construction in 2012 and was completed in November 2014 for a total cost of C$661 million ($492 million). Commercial production commenced in July 2015 and, in the first nine month of 2018, the mine produced 20,320 t of copper and 29,569 oz of gold.

Jacobs to handle underground materials work for Cadia expansion study

Jacobs has been awarded a contract by Newcrest Mining to provide underground materials handling services as part of the expansion feasibility study at Cadia, one of Australia’s largest gold mining operations.

This contract award builds on Jacobs mining and minerals business’ long history of working with Newcrest across the company’s Cadia Valley operations in New South Wales, Jacobs said.

Jacobs Mining, Minerals and Technology Senior Vice President, Andrew Berryman, said: “During the previous study phase, our mining and minerals experts helped identify a low capital intensity solution as part of an integrated team. By embracing an owners’ mindset and applying our experience in underground mining, materials handling and expansion projects, our integrated approach has the potential to deliver an impressive return on capital for Newcrest.”

The prefeasibility study on an expansion at Cadia envisaged the plant and underground materials handling upgrade costing A$58 million ($41 million). This was part of a bigger A$598 million project to incrementally increase throughput from the base case of 30 Mt/y to 33 Mt/y. Newcrest said that options to further debottleneck to 35 Mt/y would be assessed during the feasibility study.

Newcrest rolling out GE Mining collision avoidance system at Lihir

Newcrest Mining’s Lihir gold operation in Papua New Guinea is, this month, due to go live with a full installation of GE Mining’s collision avoidance system (CAS).

This follows the CAS being fitted to equipment in the Telfer open-pit mine (Western Australia) and the gradual installation of units at Lihir. Since installation 12 months ago at Telfer, vehicle-to-vehicle collisions have reduced by 33%, Newcrest said in its recently-published sustainability report.

Proximity detection technology has been progressively rolled out across the company following incidents at its operations involving collisions or near misses between vehicles and other vehicles, vehicles and pedestrians, and vehicles and infrastructure.

Supported by Newcrest’s Executive Committee, a working group comprising representatives from Newcrest’s Group Safety, Technology & Innovation, Group Supply, and key stakeholders from each of its sites, developed a strategy to deploy the technology and identified solutions suitable for use in surface and underground mining, supplied by GE Mining and Newtrax Mineprox, respectively.

Newcrest started implementing GE Mining’s CAS at Lihir back in October last year. Around 1,500 employees were to be protected in addition to up to 250 vehicles.

In addition to the GE Mining contract, Telfer and Gosowong (Indonesia) underground operations have awarded tenders to Newtrax to deploy Mineprox on the mobile mining fleets. Contractor mobilisation at Telfer commenced in September 2018.

And there could be more contract awards on the way.

Newcrest said: “Given the anticipated automation and teleremote system programme of works at Cadia (New South Wales), the business has adjusted the criteria for its proximity detection solution and is expected to award a contract soon.”