Complete Gold Cyanide Leaching Equipment for Hard Rock Gold Mining Plant

Gold cyanidation-zinc powder replacement gold extracting process flow

Gold Cyanidation- zinc powder replacement gold extracting process mainly include medicating & aeration, agitation leaching, backwashing, zinc powder replacement, gold mud smelting, tailing filter pressing, swage treatment, etc.

1. Agitation leaching- Gold leaching mainly come true in the leaching tank. Under the action of impeller and compression air, the ore pulp containing cyanide was stirred violently. It's good for leaching effect. Generally, leaching tank are used multi series.

2. Backwashing-it is the widely used proces in cyanidation plant. Generally, it use multi single-layer or multi-layer thickener. The backwashing use the next thickener's supernate to dilute last thickener's ore pulp, then the gold grade in liquid will down gradually until reach the standard. Backwashing is the ore pulp diluting & concentration process. Some cyanidation plants use filter press before the washing, then add washing water into filter cake for size mixing and washing. Generally, the first thickener's supernate as pregnant solution will be sent to zinc powder replacement system.

3. Zinc powder replacement-Add the metal reducing agent into cyanidation pregnant solution, the gold and silver will settle as gold mud via chemical reaction. Generally, it include pregnant solution deoxygenation, add zinc powder and lead acetate, filter press getting gold mud, etc. 

Main equipment

Cyanidation- zinc powder replacement gold extracting process mainly including

Crushing, Screening Process
The raw ore is fed into the primary crusher by a vibrating feeder, and then into the secondary crusher by a belt conveyor. The crushed ore is sent to the vibrating screen for sorting, the ore under the screen is sent to the powder silo, and the ore above the screen is sent to the third crusher by a belt conveyor for re-crushing. The crushed ore is then sent to the screening machine for sorting, which is a three-stage one-closed-loop crushing flow chart.
 

Grinding, Classification Process
The raw material from the powder silo is sent to the first ball mill through the feeder and belt conveyor. The ball mill discharges to the spiral classifier, and the slurry with larger particle size is returned for re-grinding. The overflow is pumped to the hydrocyclone for the second classifier, and the slurry with larger particle size enters the second ball mill, and the discharge returns to the second classifier. This is a two-step two-closed-loop grinding flow chart. The overflow of the
hydrocyclone is sent to the slag screen and thickener.
 

Concentration
After dewatering and thickening by thickener, overflow pulp density of the classifier will be adjusted to the required concentration of the leaching reaction (40%), and to ensure uniform leaching process, continuous feeding.