Pilot Plant and Metallurgical Test Work Program

Cyclone commissioned Corem to build an industrial pilot at its facilities in Quebec City which replicates the process flow sheet and is designed to calibrate the key operational parameters. The pilot plant is based on small scale industrial equipment including screens, ball mills, magnetic separation units, settling tanks, reverse flotation cells, …. etc which closely replicate larger industrial units. This is key as Cyclones strategy is based on demonstrating to potential Clients that Iron Bear can produce large scale ultra -high quality, low carbon magnetite concentrates at a competitive cost. This implies that Cyclone must produce large samples of magnetite product for testing by Clients in a manner which closely aligns to a realistic mining and processing operation. This is why the scale of the pilot is quite substantial and the bulk samples used as feed are carefully selected to represent the full life of mine and are specifically not high graded.

Pilot plant in operation at Corem, Quebec City. Source: Corem 2024

The metallurgical test work program is broken into four phases summarised below and are on track to be completed by end of August 2024. Phase 1 has just been completed with positive and exciting outcomes.

Iron Bear metallurgical testwork program overview

Initial sighter test work was completed Q4 2024 and based on the results initial product specifications were formulated and additional test work planned in Phase 1 to improve the product characteristics. A decision was taken not to target the hematite portion of the iron ore resource as the hematite is extremely fine (~ 5 microns) and combined with silica which is amenable to reverse flotation. For this reason, the objective of Phase 1 metallurgical test work was to increase the magnetic Fe yields – which was achieved.

The second area of improvement is focussed on improved the magnetite Fe recovery for the Iron Bear premium DR concentrate. Two complementary strategies are being developed.

The first strategy is to design a three-stage flotation circuit whereby the waste stream of the third flotation cell could actually be a high value saleable product in its own right – albeit with marginally higher silica content. This concept was tested, successfully, in Phase 1 of the metallurgical test work program and a RF (Reverse Flotation) concentrate was produced, grading 68,3% Fe and 4% SiO2 with an overall magnetite Fe recovery of ~ 4,5% in mass.

The RF concentrate is still a very premium iron ore product which would sell at a large premium to the benchmark 62% Fe fines (approximately 53 USD/t premium for a benchmark 62% Fe trading at USD106/t CFR). The additional 4,5% magnetite Fe recovery for the RF concentrate improves the overall magnetite recovery for the reverse flotation circuit from 80,7% (for the DR concentrate) to 85,2% which is substantial.

Output of reverse flotation circuit (1 run)

The second strategy is to improve the performance of the reverse flotation cells by adjusting the selection of flocculants and the operating conditions. This test work will be performed in Phase 2.

Reverse flotation cell

Cyclone has provided to Corem an additional seven tonnes of Iron Bear sediment to feed this pilot plant for Phase 2 test work (refer to Field operations in Schefferville, Canada, November 2023). The pilot plant will produce approximately 800 kg bulk samples of blast furnace grade and direct reduction concentrate. These concentrate samples will be used for pelletizing test work planned to start in May 2024 (milestone 8) and to provide bulk samples of Iron Bear concentrates to steel mills for validation and metallurgical test work

Iron Bear Concentrate Specifications

The following tables summarise the revised Iron Bear concentrate specifications – subsequent to the completion of Phase 1 of the metallurgical test work.

% by weight Fe SiO2 Al2O3 CaO MgO MnO P2O5 Stotal TiO2
DR conc. 71.3 1.1 <0.10 0.07 0.07 0.03 <0.01 0.005 0.01
BF conc. 69.8 3.4 <0.10 0.14 0.18 0.06 <0.01 0.005 0.01
RF conc. 68.3 4.0 0.10 0.24 0.28 0.10 0.01 0.009 0.02
% by weight K2O Na2O V2O5 ZrO2 ZnO FeO LOI Other Sum
DR conc. <0.01 <0.10 <0.01 <0.02 <0.01 29.8 -2.99 0.04 100.6
BF conc. <0.01 <0.10 <0.01 <0.02 <0.01 29.8 -2.77 0.05 100.4
RF conc. <0.01 <0.10 <0.01 <0.02 <0.01 28.5 -2.18 0.10 100.5

< = below detection limit.

  • The DR concentrate is achieved at P80 @ 32 microns with an 80.7% recovery of magnetic Fe.
  • The BF concentrate is achieved at P80 @ 32 microns with an 97.6% recovery of magnetic Fe.
  • The RF concentrate is achieved at P80 @ 32 microns with an 4.4% recovery of magnetic Fe.

The overall Fe magnetite recovery of the reverse flotation circuit is the sum of the magnetic recovery of the DR and RF concentrates (85,2%). It should be noted that both of these products are produced together if the reverse flotation is active and would sell for similar prices on the seaborne market (albeit with a silica premium for DR concentrate). However the RF concentrate is not amenable for the production of DR quality pellets which is where the highest value can be achieved for Iron Bear.