Gold CIP CIL Plant

Application
The gold CIL process is suitable for beneficiating oxidized gold ores with low sulfur content and high mud content, fine-grained disseminated gold ores, gold tailings after amalgamation with gravity separation, difficult-to-treat gold ores containing arsenic or carbon, low-grade gold mines, and gold with associated silver and copper content.
 

 

Working Principle

CIL is a cyanide-based gold extraction process. Firstly, the raw material is crushed to less than 10 mm by various types of crushers. Secondly, the crushed material is ground and classified to 90% passing 200 mesh. The fine powder is then fed into a thickener. After thickening, chemicals are added and the slurry is leached in the leaching tank. Following leaching, activated carbon is used to adsorb the gold, producing gold-loaded carbon. Finally, electrowinning or smelting is applied to produce gold bars.
 

Introduction to Flow Chart 

A. Raw materials preparation:

The raw ore is fed to the primary crusher via a vibrating feeder, and then to the secondary crusher via a belt conveyor. The crushed ore is then fed to a vibrating screen for separation. The undersize ore is sent to a powder silo. The oversize ore is then fed to the tertiary crusher via a belt conveyor for secondary crushing, and the crushed ore is again fed to a vibrating screen for separation. This process flow is called a three-step closed-loop crushing process flow diagram.
 

 

The raw materials in the powder silo are fed to the first ball mill via a feeder and belt conveyor. The ball mill discharge is sent to a spiral classifier, where larger particles are returned for secondary grinding. Overflow material is pumped to a hydrocyclone and then classified in a second ball mill: larger particles enter the second ball mill, and the discharge is returned to the second ball mill. This process is called a two-step, two-closed-loop circulating grinding process. Overflow material from the hydrocyclone is sent to a screening machine and a thickener.
 

 

B. Leaching and adsorption:

The slurry will enter eight sets of double-impeller leaching tanks; a fully mixed sodium cyanide leaching agent will be added to the first tank; activated carbon will be added sequentially from the second to the eighth tank; the activated carbon in the second tank will be lifted to a carbon screen to obtain gold-bearing activated carbon, which will then be washed and enter the desorption electrolysis system; the remaining slurry will be returned to the second tank; the activated carbon will be lifted countercurrently from the adjacent tank by an air lifter; the tailings will be screened to recover fine gold-bearing activated carbon and then enter the tailings treatment stage.

C. Tail water treatment:

Tailings are lifted to a filter press, and the filter cake, also known as tailings, is transported to a stockpile via belt conveyor and trucks. The filtrate is then recycled into a circulating water tank, which helps save on lime and sodium cyanide.

 

 

D. Gold-loaded carbon treatment:

Gold-containing carbon is processed in batches using a desorption electrolysis device to obtain gold powder. The gold powder is then fed into a smelting furnace to be smelted into gold bars. The electrolyzed gold-containing carbon can be returned to the final stage of the process flow for further processing.