160
D. Dreisinger et al.
The liquor (thickener overflow) is fed to a leaching circuit, where it mixed with
sulphuric acid to precipitate gypsum and strontium and regenerate MSA. The precipitate is thickened, filtered, and washed before being discarded to tailings. The liquor
is returned for reuse in the MSA leach.
Utilities and Reagents
The following utilities are provided for the hydrometallurgical facility:
• Raw Water;
• Fire Water;
• Cooling Water;
• Potable Water;
• Plant and Instrument Air; and
• Environmental collection pond for water from bunded process areas.
Storage, mixing, and pumped distribution facilities are provided for the following
reagents:
• Sodium hydrosulfide (NaHS);
• Sodium Isobutyl Xanthate (SIBX);
• Frother;
• MSA;
• Sulphuric Acid;
• Lime;
• Soda ash;
• Flocculants (2);
• Caustic Soda;
• Orthophosphoric acid;
• Aloes; and
• EW50.
Lime and soda ash and acid are delivered in bulk. The other reagents are delivered
in isotainers or bulka-bags. A lime slaking plant is provided to produce lime slurry
for use in the circuit.
Tailings Disposal
Waste streams from both the flotation concentrator and the hydrometallurgical facility
are disposed using the existing concentrator tailings sump and pumps and delivered
to the integrated waste landform.