Tag Archives: HydroFloat

Anglo’s Quellaveco to receive the coarse particle recovery treatment

Anglo American has approved the construction of a coarse particle recovery (CPR) plant at its in-development Quellaveco copper project in Peru.

The announcement came within the company’s 2020 financial results, which showed Anglo generated underlying EBITDA of $9.8 billion and a profit attributable to equity shareholders of $2.1 billion for the year.

CPR, Anglo says, is one of many significant breakthrough technology initiatives that has the potential to increase throughput and productivity, while simultaneously reducing environmental footprint, through rejection of coarse gangue (near-worthless waste material), dry stacking of sand waste, minimising the production of traditional tailings and reducing overall water consumption.

The CPR plant signoff at Quellaveco follows a full-scale demo plant installation at the company’s El Soldado mine in Chile – which is ramping up to full capacity by mid-2021 – and the decision to construct a full-scale system at the Mogalakwena North PGM concentrator in South Africa.

The El Soldado plant used the HydroFloat™ CPR technology from Eriez’s Flotation Division. Here, a single 5 m diameter HydroFloat cell, the largest in the world, treats 100% of mill throughput, with the objective of proving the waste rejection process at full scale.

Anglo said of the Quellaveco CPR plant: “This breakthrough technology will initially allow retreatment of coarse particles from flotation tailings to improve recoveries by circa-3% on average over the life of the mine. This investment will also enable future throughput expansion which will bring a reduction in energy and water consumption per unit of production.”

The capital expenditure of the CPR project is around $130 million, with commissioning of the new plant expected in 2022. DRA Global previously carried out a feasibility study for the CPR plant at Quellaveco.

In terms of Quellaveco project progress, Anglo said today that, despite the COVID-19-related slowdown, first production was still expected in 2022. This was, in part, due to the excellent progress achieved prior to the national lockdown, and based on optimised construction and commissioning plans, Anglo said.

Key activities in 2021 include the start of pre-stripping, which will see the first greenfield use of automated hauling technology in Peru; progressing construction of the primary crusher and ore transport conveyor tunnel to the plant; completion of the 95 km freshwater pipeline that will deliver water from the water source area to the Quellaveco site; completing installation of the shells and motors for both milling lines; and completion of the tailings starter dam.

The mine, owned 60% by Anglo and 40% by Mitsubishi Corp, comes with a production blueprint of 300,000 t/y over the first 10 years of the mine.

Eriez HydroFloat technology to help improve recoveries at Newcrest’s Cadia operation

Eriez Flotation is to supply four HydroFloat® Separators to Newcrest Mining for use in Stage 2 of the miner’s Cadia Valley Operations (Cadia) expansion project in New South Wales, Australia.

This announcement follows the successful delivery, commissioning and ramp up of four Eriez CrossFlow Separators and two HydroFloats as part of the Cadia Coarse Particle Flotation demonstration plant in 2018.

Eriez Flotation Global Managing Director, Eric Wasmund, says: “When Stage 2 of the Cadia Expansion Project is complete, 100% of the Concentrator 1 tailings will be re-treated, significantly improving overall plant recovery for a coarser primary grind.”

The Stage 2 Cadia Expansion project primarily comprises the addition of a second coarse ore flotation circuit in Concentrator 1, using Eriez’s HydroFloat technology, and equipment upgrades in Concentrator 2, Newcrest said back in October. 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.

Newcrest is the first mining company to commercialise HydroFloat coarse particle flotation in sulphides and the first
in a tail scavenging application.

Wasmund added: “Eriez has been very fortunate to partner with Newcrest on coarse particle flotation. As partners we have learned many lessons together.”

Eriez-Australia Managing Director, James Cooke, noted: “During the commissioning of the demonstration plant, Eriez and Newcrest Mining worked closely together to perfect the technology. The decision was subsequently made to expand the application.”

Capstone considering Eriez HydroFloat tech to boost Pinto Valley performance

Capstone Mining is continuing to leverage innovative, low-cost technology at its Pinto Valley mine in an attempt to further utilise its existing solvent-extraction and electowinning (SX-EW) plant at the Arizona, USA, operation.

In the December quarter of 2019, Pinto Valley commenced a PV3 Optimization project designed to achieve safer, more reliable and higher capacity operations without major investments in new comminution equipment. A goal was set to achieve increased reliability, and higher throughput at maximised copper recovery with lower costs by leveraging new inexpensive technologies.

In its September quarter results, the company provided an update on this project, saying, to October 27, it had spent $17 million as part of its Phase 1 developments. This included crushing and mill equipment replacements, which are 60% complete with full completion expected by July 2021.

As part of its Phase 2 developments, Capstone spent $10 million in conveyor, mill auto controls, cyclone packs and tailings thickener upgrades. These upgrades are planned to be completed by the end of the September quarter of 2021.

On top of this, the miner completed a blast fragmentation optimisation project to target 30% fines (minus-0.5 in) in run of mine feed in the June quarter. In the same quarter, it completed a $300,000 tele-remote Cat D10 Dozer project to increase worker safety for high-risk applications. Another $6 million was spent on new mine equipment to increase efficiency while lowering diesel consumption, greenhouse gas emissions and other operating costs by $800,000/y. This project was completed in the September quarter.

In terms of its metallurgical innovation, the company continued to use novel catalytic technology developed by Jetti Resources at Pinto Valley, expected to deliver 300-350 MIb of copper cathode over the next 20 years from high-grade mine waste and historic stockpiles at all-in costs under $2/Ib. This technology uses a catalyst on primary sulphide minerals to disrupt the sulphur metal bond of the mineral and allow for a leaching solution to contact the copper. This enables the extraction of the metal to take place unimpeded.

Capstone also made plans to use new reagents to improve worker safety and improve overall metallurgical performance at its molybdenum plant re-start project. This would involve “minimal capital” and completion was targeted by the March quarter of 2021, it said.

Capstone says it is targeting to reach 60,000-63,000 t average daily throughput at Pinto Valley at an 85-90% recovery by 2022-2023. This is 17-30% higher than 2019 performance and is subject to further test work and studies to be completed in the first half of 2021, including tailings management, the company explained.

Added to this, following positive laboratory results on Pinto Valley flotation circuit samples, Capstone and Eriez are planning to commence pilot plant testing of the HydroFloat technology.

The HydroFloat fluidised bed assisted flotation cell has previously proven effective at floating coarse ore particles, up to two to three times the size limit of conventional flotation cells in commercial applications such as at Newcrest Mining’s Cadia Valley operation in Australia. Newcrest has recently decided to expand the use of this technology at the operation.

Capstone says the lab results at Pinto Valley had led Eriez to report an opportunity to reduce copper losses by up to 50%, thereby boosting overall recovery by up to 6% at Pinto Valley.

“Furthermore, the ability to recover coarse particles could allow for higher mill throughput while achieving high copper recovery,” Capstone said.

Other benefits could be lower grinding costs, lower water and energy consumption and increased tailings stability via coarser tailings.

Pilot testing is due to commence in November with results expected back in the March quarter of 2021.

Lastly, work on PV4 expansion scenarios to take advantage of around one billion tonnes of measured and indicated resources at 0.30% Cu continued during the September quarter.

“Given management’s confidence in PV3 Optimization progress to date, including the successful implementation of the novel catalytic technology from Jetti Resources to enhance leaching performance, Capstone has decided to evaluate expansion scenarios using existing assets rather than building new mill infrastructure,” the company said.

The study is assessing higher mining rates, higher cutoff grades to the mill, and an increased tonnage available for leaching.

While a significant mill expansion is not currently being contemplated, an expansion of Pinto Valley’s SX-EW capacity of 25 MIb/y may be necessary, it said. Extensive column leach test work will be conducted over 2021, with the overall PV4 expansion study expected to be released in 2022, Capstone added.

Anglo American, Glencore, Newcrest and Newmont join coarse particle recovery consortium

Researchers from The University of Queensland’s Sustainable Minerals Institute (SMI) have signed an agreement with industry partners to form a consortium to develop improved energy efficiency for mineral processing operations.

The Collaborative Consortium for Coarse Particle Processing Research will run initially for five years and tackle multidisciplinary aspects of coarse particle processing such as flotation, comminution, classification, and equipment design and process chemistry, SMI says.

It will also contribute towards global challenges such as the reduction of greenhouse gas emissions and mitigation of human-made climate change.

The processing of coarse particles is considered one of the key research areas for developing improved energy efficiency of mineral processing operations, according to SMI.

The consortium includes researchers from SMI’s Julius Kruttschnitt Minerals Research Centre (JKMRC) and representatives from Anglo American, Aeris Resources, Eriez Flotation Division, Glencore, Hudbay Minerals, Newcrest Mining and Newmont.

The program Chair is SMI Director, Professor Neville Plint (far left). JKMRC’s Associate Professor, Kym Runge (right), and Dr Liza Forbes (middle) are the Technical Directors.

Professor Plint said SMI and JKMRC have a long history of successful industry engagement.

“This consortium brings together depth and breadth of expertise and significant technical skill, and it shows the willingness of industry to work closely with university researchers to tackle complex problems and have an impact,” he said.

“The team in JKMRC have worked hard and consulted with all our industry partners to create this important forum.”

Newmont’s Director of Processing, Dr Ronel Kappes, said the company had identified coarse particle recovery (CPR) as a key enabling technology to focus on, in order to improve future processing efficiencies.

“The UQ CPR Consortium project is an important step in technology development in order to leverage future CPR applications,” Dr Kappes said.

Eriez Flotation Division’s, Dr Eric Wasmund, said the company was pleased to be a founding sponsor of the consortium.

“This consortium fits EFD’s vision to enable sustainable technology solutions through strong customer partnerships,” he said. “As demonstrated by our leading-edge HydroFloat® technology, coarse particle flotation is a key disruptive technology for improving mineral recoveries, reducing power and water consumption and producing safer tailings.”

The CPR Consortium held its first technical workshop at the end of September.

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.