RE:Iron ore sales in Q4-21? Is the sodium problem solvable considering the fact that sodium salt is soluble?
From the last Technical Report / PEA (by GE21- 2017)
Calcine Residue Stack
The calcine residue tailings consist of synthetic hematite (calcined magnetite) that will contain, regardless of the effectiveness of the leaching and filtering processes, some residues of vanadium and sodium salts soluble in the form of sodium vanadate (NaVO3, Na3VO4, Na6V10O28).This material is stacked in a lined and impermeable structure after filtering and washing.The residue stack was formerly wetted by sprinkling water on top of it, progressively washing for removal of soluble salts. The solution will be collected in tanks and returned by pumping to the metallurgical plant thereby limiting potential infiltration into the subsurface.The residue remaining on the stack is considered a Class I (dangerous), and the leaching pad is fully waterproof with high density dual layer polyethylene.This material is not being sold, however Largo continues to explore opportunities to sell this material as iron ore. The report considered that this material will be stored in appropriate areas (calcined dams). The capex for these storage areas are included in the sustaining capital costs for the plant (US$ 3 million per year).