ALTA_2020 - ReCYN III The New Generation of Gold Plants


Slurry Flow Resin Flow Solution Flow

Carbon Safety Screen U/F Metal Eluted Resin

Resin Sizing Screen



Precipitate Thickener

Loaded Resin Screen

H 2 SO 4


Copper Elution Column

Metal Adsorption Tank

Filter Feed Tank

Copper Reactor Tank

Loaded Resin Tank


Copper Filter

Copper Concentrate

Zinc Filter

Zinc Filtrate

Gold Elution Column

Zinc Reactor

NaCN soln

Electrowinning Cell

ZnSO 4 .7H 2 O

Gold Eluant


Gold Bullion

Drying Oven


Cyanide Eluted Resin

Scrubbing Column

Resin Sizing Screen

Loaded Resin Screen



Cyanide Adsorption Tank

Cyanide Elution Column

Safety Screen

Recycle Cyanide Solution to Leach Tank

Recycle Cyanide Tank

Loaded Resin Tank

H 2 SO 4

Tailing Dam

Tailings Hopper

Fig. 3. ReCYN III Flowsheet

Operations with low copper levels can by-pass the chloride elution step, using the gold elution step to remove the copper and other metal cyanide complexes. The final stage in the gold elution is resin regeneration, which uses sulphuric acid to remove the zinc that has loaded onto the resin during the copper and gold elution. The zinc is recovered by precipitation and recycled to the gold eluant tank. RECYN CHEMISTRY The ReCYN process is based on the use of a strong base, macroporous, anionic, polystyrene resin beads. The resin is sized to provide a +1mm diameter bead and partially pre-conditioned prior to use. Resin production methods have improved over the years to ensure a robust product, resilient to osmotic shock and abrasive wear. However, this does not apply to all suppliers. The ReCYN process ensures minimum resin handling to reduce resin abrasion losses. The ReCYN circuit can contain fifty billion beads of resin (approximately), forming a homogenous mix of several resin forms. The form of each resin bead entering metal adsorption will depend on its elution history. Copper eluted resin will be in the chloride form and gold eluted resin will be in the sulphate form. Both forms of eluted resin will adsorb metal cyanide complexes. Some free cyanide will also be adsorbed. The cyanide recovery circuit is kept separate to maximise the copper loading and therefore maximise free cyanide recovery. At the start of commissioning a ReCYN plant, conditioned resin is added to the cyanide adsorption train. For conditioning, the new resin is pre-treated with a synthetic copper cyanide solution (similar

ALTA 2020 Gold-PM Proceedings


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