PROJECT ALUMINA Refinery (NIMBA MINING COMPANY)
The Project is proposed to be located in Sangarédi, Republic of Guinea, approximately 124 km northeast of Kamsar Port and about 54 km northeast of Boké. It is situated approximately 200 km southeast of Conakry, the capital city of Guinea.
The Alumina refinery site has been selected within the NMC Mining Permit.
With abundant bauxite resources in Guinea, the NMC Alumina refinery benefits from ample high-grade bauxite ore characterized as gibbsitic bauxite, featuring low silicon content and perfectly fitting the Low-Temperature Bayer Process as the primary technology for alumina production.
Low-Temperature Bayer Process
The Low-Temperature Bayer Process involves the direct treatment of bauxite with a circulating mother liquor rich in free NaOH, facilitating the digestion of alumina to obtain sodium aluminate solution.
By employing seeding and precipitation techniques, alumina is crystallized as alumina, and the seed-rich mother liquor, after evaporation, is recycled for bauxite leaching.
The Low-Temperature Bayer Process offers several key advantages, including:
- Straightforward process flow
- Low energy consumption
- High product quality
- Cost-effectiveness when dealing with high-grade bauxite ores
Process Flow Diagram
The process flow includes key stages such as raw material milling, desilication, digestion, dilution and retention, red mud separation and washing, filtration, precipitation, evaporation, baking, and finished alumina production.
