Process principle:The cyanide-zinc replacement process is used to treat the gold-containing leaching solution after cyanidation leaching. The principle is to use zinc as a reducing agent to replace gold and silver from the leaching solution, replacement, etc.

Process flow:The cyanide-zinc replacement process mainly includes three processes: leaching, washing, and replacement (precipitation):
①Leaching - The solid gold in the ore is dissolved in an oxygen-containing cyanide solution.
②Washing - recover the gold-containing solution after leaching, wash the surface of the ore particles and the melted gold between the ore particles with water to achieve solid-liquid separation.
③Replacement - use metal zinc in the gold-containing leaching solution to reduce and precipitate it to recover gold.

Process principle:The carbon slurry gold extraction method, also known as the all-slime cyanidation method, is a method in which activated carbon is put into the cyanide pulp, so that the dissolved gold is adsorbed on the activated carbon, and then the gold is extracted from the activated carbon. It mainly includes the preparation of leaching raw materials, stirring leaching and countercurrent carbon adsorption, gold-loaded carbon desorption, electrowinning and electrolysis, smelting and ingot making, and carbon regeneration. It is suitable for gold mines with low sulfur and silver content and high mud content, and the recovery rate can reach more than 90%.

Process flow:The process steps of gold extraction by carbon slurry method mainly include preparation of leaching pulp, cyanidation leaching, activated carbon adsorption, gold-loaded carbon desorption, electric shock to obtain gold mud, de-gold carbon recycling, and treatment of leaching pulp. There are seven working stages.
①Preparation of leaching pulp: crush the gold-containing ore to a particle size suitable for cyanidation leaching, and remove impurities from the pulp, mainly to remove wood chips to prevent it from clogging the carbon screen.
②Cyanide leaching: stirring and leaching the pulp with the aid of chemicals.
③Activated carbon adsorption: The pulp after cyanidation leaching is introduced into the adsorption tank, and the dissolved gold in the pulp is adsorbed by activated carbon, thereby becoming gold-loaded carbon.
④Desorption of gold-loaded carbon: The gold-loaded carbon is separated from the pulp by means of a carbon extraction screen, and the gold complex is replaced in the desorption system.
⑤Gold mud obtained by electric shock: The precious liquid obtained by desorption of gold-loaded carbon is recovered by electric shock to obtain gold mud.
⑥Recycling of de-gold carbon: After desorption, activated carbon is treated to remove other aggregates and then enter the adsorption tank for recycling.
⑦Treatment of leaching pulp: The leaching pulp containing cyanide cannot be directly discharged, and can be treated by means of sodium hypochlorite generator or chlorine gas, acidified volatile alkali liquid absorption method.