Tag Archives: Corem

COREM, Steinert ore sorting tests present opportunities for Cartier at Chimo gold project

Cartier Resources says ore sorting tests carried out by COREM and Steinert US on mineralised samples from the Chimo Mine property, in Quebec, Canada, have indicated gold grades could increase substantially with the use of the pre-concentration technology.

Gold from Chimo is present in two types of mineralised facies: i) quartz veins with coarse visible gold grains having an affinity for the gravity concentration of gold at the mill and ii) zones of silica-rich mafic rocks associated with non-refractory arsenopyrite having an affinity for the flotation of a concentrate of arsenopyrite for gold recovery at the mill.

To perform the sorting tests, rocks representative of the two mineralised facies, made up of the following six mineralogical facies, were first selected for static recognition of each of the facies by the sensors of the sorter:

  • Gold-bearing quartz veins;
  • Gold-bearing silica;
  • High grade gold-bearing arsenopyrite;
  • Medium grade gold-bearing arsenopyrite;
  • Low grade gold-bearing arsenopyrite; and
  • Mafic waste rock.

The detection sensors of the industrial sorter at COREM in Quebec, Canada, were the RGB camera using the optical properties of reflection, brightness and transparency to locate quartz and silica and the X-ray Transmission sensor using the volumetric property of atomic density to locate arsenopyrite. The two sensors adequately recognised the six mineralogical facies associated with the mineralisation, with dynamic calibration tests of the sorter with the moving conveyor making it possible to sort, one at a time, 2 kg samples of each of the facies, Cartier said.

The results of this first test at COREM showed the first three sorts (on a total of eight sorts) concentrated 99.1% of the gold contained in 44.4% by mass of material mass for a grade of 56.3 g/t Au, representing a percentage increase of 223% in gold content over sorter feed. The reject, representing 0.9% by mass of material, contained only 0.4 g/t Au.

The sorter was then ready to perform sorting tests on the 105.7 kg production sample, representative of the mineralised facies at an average grade of 2.16 g/t Au. This content was obtained by including 20% by mass of material with zero grade of gold, simulating dilution in the stopes. COREM’s sorting plan separated 53.9% by mass of the material in the form of a preconcentrate at an average grade of 3.68 g/t Au, representing an increase of 170% in the gold grade compared with the sorter feed. The waste disposal, separated from the mineralisation, represented 46.1% by mass of material at an average grade of 0.38 g/t Au.

Sorting tests carried out with Steinert in Kentucky using a Steinert KSS FLI XT machine with XRT, colour, laser, and induction sensors yielded comparable results.

A 80.69 kg production sample, representative of the mineralised facies at an average grade of 2.13 g/t Au, to which 20% by mass of material at zero grade of gold was added mathematically, representing the dilution in the workings, was used for testing. The new calculated diluted grade was 1.55 g/t Au.

Calculation of the results revealed that 51% by mass of the dilute grade material could be separated as a preconcentrate at an average grade of 2.72 g/t Au, representing a 175% increase in gold grade compared with the sorter feed. The waste disposal, which would be separated from the mineralisation, would represent 49% by mass of material at an average grade of 0.36 g/t Au.

Sorting tests with COREM were carried out following these tests to validate that the 20% of dilution material at zero grade of gold, mathematically added, could physically be effectively separated by the sorter, Cartier said.

The sorting tests carried out by both COREM and Steinert US were comparable, with these results providing prospects for increasing the value of the resources with ore sorting technology.

The objective of the industrial sorting of the mineralisation is to increase the grade of the preconcentrated material preceding the milling operations, which allows an increase in the recovery rate at the mill, reduces transport costs to the mill, reduces milling costs, reduces the costs of environmental restoration of mine tailings, and reduces the environmental footprint of mine tailings and, consequently, increases the social acceptability of the mining project, Cartier said.

The most recent resource estimate from Chimo included 6.6 Mt at an average grade of 3.21 g/t Au for a total of 684,000 oz of gold in the indicated category and 15.2 Mt at an average grade of 2.77 g/t Au for a total of 1.36 Moz of gold in the inferred category.

CMIC-backed novel comminution technology hits commissioning milestone

The Canada Mining Innovation Council’s (CMIC) Conjugate Anvil Hammer Mill (CAHM) and MonoRoll platform technology project has reached a new milestone with hot commissioning of the MonoRoll at COREM’s testing facility in Quebec, Canada.

CAHM is a platform technology advancing two technologies in parallel where both designs break particles in a highly efficient thin particle bed. CAHM, according to CMIC, provides a more efficient alternative to high pressure grinding rolls and SAG mills, while the MonoRoll variant is designed for finer grinds and to replace inefficient rod and ball mills.

In a recent post, CMIC said hot commissioning of the MonoRoll at COREM’s testing facility, using some of the 300 t of ore contributed by Agnico Eagle Mines, was now complete. Although the MonoRoll is being tested using hard rock, there is also significant interest from the iron ore, cement and aggregate industries, CMIC says.

It added: “Fabrication of the CAHM machine is underway and if the optimised discrete element method modelling results hold, we are confident that the MonoRoll and the CAHM are on track to achieve the following significant benefits in ore grinding:

  • “Reduce energy consumption by an estimated 50% compared to best available technology;
  • “Eliminate grinding media;
  • “Increase ore feed reduction ratio; and
  • “Simplify the comminution circuits.”

CMIC is leading a consortium including experts in comminution, product development, engineering and testing as well as six major hard-rock mining companies guiding the effort and participating as potential first adopters. Included among the consortium is CTTI, Hatch, Glencore Canada – XPS (Expert Process Solutions), COREM, Teck, Agnico Eagle, Newmont and Kinross.

The MonoRoll technology is one of only six finalists in Impact Canada’s Crush It! Challenge. Launched in October 2018, Crush It! challenged Canadian innovators to deliver game-changing solutions for cleaner, more efficient rock processing.

CMIC said: “The MonoRoll project is the only finalist developing a novel grinding mill, and if the project wins the C$5 million ($3.9 million) Grand Prize, the funds would be used to engineer a large-scale machine to test in active mining operations.”

Corem’s cyanide recovery and recycling process wins federal, provincial backing

Quebec-based Corem is to receive C$2.1 million ($1.6 million) of funding from the Canadian government to support the development of an innovative process for the recovery and recycling of cyanide in the gold extraction process.

This new process is more environmentally sustainable and reduces the impact of gold mining on the aquatic ecosystem, according to Natural Resources Canada.

The announcement was made by Jean-Yves Duclos, President of Treasury Board of Canada and Member of Parliament for Quebec, on behalf of Seamus O’Regan, Canada’s Minister of Natural Resources. The Quebec Ministry of Energy and Natural Resources is also contributing an additional C$100,000 to this project, according to the government.

Following this cash injection provided through Natural Resources Canada’s Clean Growth Program, Corem will work to accelerate the deployment of the process at commercial scale by constructing a pilot-scale processing plant, NRC said.

“Corem’s promising recycling technology is expected to reduce the volume of contaminated water stored in tailings ponds, thereby contributing to the sustainability and competitiveness of the mining industry,” it added.

Francis Fournier, President and Chief Executive Officer of Corem, said: “This financial support demonstrates the importance and interest in the development of clean technologies for the mining industry and the Government of Canada. It allows Corem to pursue its mission of developing innovative solutions for the benefit of a sustainable mining industry and of working closely with our members, our customers and our partners.”

The Clean Growth Program invests in clean technology research and development projects in Canada’s energy, mining and forest sectors. The program is a C$155 million investment fund that helps emerging clean technologies further reduce their impacts on air, land and water while enhancing competitiveness and creating jobs, it says.

It also provides federal laboratory support for innovators under the Science and Technology Assistance for Cleantech initiative, which is intended to help bring Canadian clean technologies to market by providing federal research expertise, facilities and equipment.