Recycling approach and technological process of lead-zinc mine tailings

Lead-zinc mine tailings contain a considerable amount of valuable metals, including lead, zinc, silver, and even gold, which can be recovered through recycling approaches. The following is a technological process of lead-zinc mine tailings recycling:

1. Tailings regrinding: Tailings are ground to 80% passing 74μm to increase the surface area of the mineral particles and expose the valuable metals.

2. Flotation: The ground tailings are subjected to flotation to separate the valuable metals from the gangue minerals. The flotation process is usually a rougher and cleaner stage, followed by scavenging and recleaning stages.

3. Magnetic separation: After flotation, the rough concentrate is sent to magnetic separation to remove the magnetic minerals such as pyrrhotite, which affects the quality of the final concentrate.

4. Gravity separation: The magnetic concentrate is treated by gravity separation, mainly using the Wilfley table, to separate the heavy minerals from the light ones. The final concentrate contains lead, zinc, and silver.

5. Cyanidation: The tailings from the gravity separation are treated by cyanidation to recover the gold, which is often present in trace amounts.

6. Re-flotation: The tailings from the cyanidation are subjected to re-flotation to recover the residual lead, zinc, and silver, which increases the recovery rate of the valuable metals.

7. Tailings dewatering: The final tailings are dewatered using a thickener or a filter press to reduce the water content and make them easier to handle and store.

The cost of the technological process of lead-zinc mine tailings recycling depends on various factors such as the grade of the tailings, the recovery rate of the valuable metals, the equipment used, and the operating cost. Therefore, it is difficult to estimate the exact cost without specific information. However, recycling lead-zinc mine tailings can bring significant economic and environmental benefits by reducing the need for primary mineral resources and preventing environmental pollution.