CIL (Carbon-In-Leach) and CIP (Carbon-In-Pulp) are two common gold extraction processes that belong to the category of gold leaching. The main difference between them lies in the way the activated carbon, which adsorbs gold, is handled during the gold leaching process.
CIL stands for Carbon-In-Leach, which primarily uses the characteristic of activated carbon to adsorb gold by bringing gold into contact with gold-containing slurry and adsorbing it onto the surface of activated carbon. In this process, the slurry is sent into a leaching tank before the addition of activated carbon, where the gold is dissolved out of the slurry by an oxidant (such as air). Activated carbon is then added to the tank to adsorb gold ions and remove them from the slurry. Finally, the gold is desorbed from the activated carbon through methods such as heating or compression and collected.
CIP stands for Carbon-In-Pulp, which also utilizes the characteristic of activated carbon to adsorb gold by bringing gold into contact with gold-containing slurry and adsorbing it onto the surface of activated carbon. Unlike the CIL process, the CIP process discharges the gold-containing slurry from the leaching tank and transfers the gold-bearing activated carbon to an adsorption tank for regeneration and cleaning before returning it to the leaching tank for continued adsorption. In this process, the leaching and adsorption of gold occur simultaneously, which can increase the recovery rate of gold.
Overall, both CIL and CIP gold extraction processes utilize the characteristic of activated carbon to adsorb gold, and the main difference lies in the way activated carbon is handled. The CIP process is more flexible and efficient in the handling of activated carbon than the CIL process, but the equipment investment and maintenance costs are relatively high. The selection of which process to use should be based on the specific characteristics of the gold mine and the actual situation, and should be considered comprehensively.