Bridging Fundamental Science With Real-World Applications

Carbothermic reduction of chromium and iron aided by molten salt

Paktunc D, Coumans JP, Carter D, Zagrtdenov N, Duguay D. (2024) Mechanism of the Direct Reduction of Chromite Process as a Clean Ferrochrome Technology. American Chemical Society, Engineering Au, 4, 125-138.

• Incongruent dissolution of chromite in molten salt

• Transport of Fe and Cr species and reduction on carbon particles

• Shrinking cores of chromite and carbon particles

• Refractory spinel and ferrochrome alloy particles as final products

Large-scale reduction tests

Photos of reduced pellets from 4 pellet-high stack

Alloy particles are readily separated and recovered from the furnace products through conventional classification and gravity separation techniques with alloy recovery figures reaching 90% for alloy grades of ~95% for rougher concentrates. Addition of a cleaner circuit such as MGS, LIMS and/or Falcon will enhance the grade-recovery figures.

Red: alloy Green: spinel Yellow: forsterite

Mineral Processing Flow Sheet

Large-scale tests were carried out on 1-1.5 kg charges making 2 to 4 pellet high stacks to assess heat transfer limitations and to determine pellet bed height

Recovery of ferrochrome

DRC product - SEM-based Mineral liberation analyzer

Products of DRC are solid ferrochrome and slag particles which are separated by conventional mineral processing techniques