Gold ore CIL (Carbon In Leach) process, that is, carbon leaching method for gold extraction, is a process of adding activated carbon to the pulp and leaching and adsorbing gold at the same time. Two steps are one step, reducing management costs while reducing losses. Compared with the traditional CCD process, it saves 66% of the investment cost. It is the main process of modern gold beneficiation.
Gold mine CIL process is suitable for beneficiation of large-scale gold mines with high grades and gold mines with high content of associated silver and copper. Compared with the carbon slurry method and the traditional method, this method can obtain significant economic benefits. For small gold mines, Xinhai proposes to use concentrate gold ore flotation process.
After the crushing and grinding stage of the CIL gold ore process, the pulp is put into 9 high-efficiency cyanidation leaching tanks arranged in steps, and the first 2 leaching tanks are cyanided, and the last 6-7 leaching tanks are carried out. Activated carbon was added while cyanidation for countercurrent adsorption. Compared with the CIP gold mine process and other traditional gold mine processes, the carbon leaching gold process greatly shortens the cyanidation operation time and reduces the backlog of funds in the gold retention link. Taking the cyanidation plant of t gold mine as an example, the CIL carbon leaching method saves US$486,000 in investment cost compared to the CIP method, and reduces the backlog of gold in production by US$201,700. After deducting the extra activated carbon cost of US$12,600 in the process, $675,100 in savings and early recovery.
In the process of adding activated carbon, activated carbon is added to the pulp, and the gold-silver ions are dissolved and adsorbed to form gold-loaded carbon by utilizing its characteristics of adsorbing gold and silver. Compared with the traditional process, the dissolution of gold and silver in the CIL carbon leaching process design is accompanied by the adsorption of activated carbon on it, and it will not be affected by the high ion concentration. The recovery rate of precious metals can significantly improve economic benefits.
Dehydration and stirring
Vibration and dehydration equipment is the key equipment for the reverse movement of pulp and carbon. Hydraulic filter press and high-efficiency high-frequency dewatering screen can effectively reduce the carbon wear of pulp in continuous pumping and vibrating screen surface, reduce costs, and facilitate maintenance operations. The central air-filled riser used in the stirring process can make the slurry circulate in a small way. Compared with other mechanical stirring tanks, this design can reduce the power consumption by 70%, and the solid material is evenly suspended, the activated carbon wear is small, and the gold recovery rate high. It is an important equipment in a modern cyanide plant.
High-temperature desorption electrolysis of gold in gold-loaded carbon was carried out using a mixture of sodium cyanide and sodium hydroxide. First, remove debris such as wood chips by elutriation, and then use high temperature and high pressure desorption method to desorb gold under high temperature and high pressure environment of 150 degrees Celsius and 0.5Mpa. This design can desorb 99% of gold within 2-6 hours. . The gold-silver cyanide complex ion concentration in the precious liquid obtained by desorption of gold-loaded carbon is relatively high, and the impurity ions are greatly reduced, which provides an ideal solution for the reduction and recovery of gold from the precious liquid by electrowinning. The high-purity solid gold can be obtained safely and economically.
1. The carbon leaching process for gold extraction greatly shortens the cyanidation operation time and saves costs.
2. Greatly improve the recovery rate of precious metals such as silver, copper and other associated metals.
3. Effectively reduce the carbon wear of pulp on continuous pumping and vibrating screen surface, reduce costs and facilitate maintenance operations.
4. Larger output and lower beneficiation cost, suitable for large-scale gold beneficiation industry.