Gold Tailings Treatment And Recovery
Gold tailings treatment and recovery usually adopt reasonable technology to re-select the tailings, so that the useful components in the tailings can be recovered to a limited extent, so that the number of tailings can be further reduced. Tailings are components that have a low content of useful components produced in beneficiation operations and cannot be economically used in industrial production at present and are also the main component of industrial solid waste.
Common gold mine tailings treatment methods:
1. Gold tailings reselection
The gold content in gold mine tailings is generally 0.2-0.6g/t. In addition to gold and silver recovery, the gold tailings re-selection process can also comprehensively recover other valuable elements according to the nature of the tailings. Therefore, tailings re-selection has become a major trend in the current gold mine tailings treatment.
Take the recovery of lead and zinc from gold tailings as an example, the lead-zinc minerals in the gold concentrate have undergone fine grinding and long-term aeration and stirring during the cyanide leaching process, and severe over-grinding has occurred, which makes flotation difficult. In addition, a large number of argillaceous minerals and residual cyanide make a thin film on the surface of the mineral, so that the collector loses its selectivity for the collection of various minerals. The film also hinders the adsorption of the collector and the surface of the ore particles, increasing the difficulty of flotation separation.
- The flotation of ultrafine particles can be achieved through pretreatment, combined collectors, pH control, and other measures.
- The slurry pretreatment technology such as strong oxidation of concentrated sulfuric acid and activated carbon adsorption can be used. Using mixed flotation technology in an acid medium to improve the comprehensive utilization rate of lead and zinc mineral resources in cyanide tailings.
2. Gold tailings dry discharge process
For gold tailings after gold extraction using all-slime cyanidation, the tailings filter press process of a filter press can be used. Most of the cyanide ion, alkali, and dissolved gold in the filtrate is recovered. The recovered clean water is returned to the process flow, saving water and reducing the discharge of cyanide-containing sewage. The dry tailings discharge process eases the pressure on the storage capacity of the tailings reservoir, and the utilization of backwater reduces the pressure on sewage treatment and saves the production and operation costs of the mine.
3. Production of building materials
Gold mine tailings can be used directly as important non-metallic raw materials or building materials, such as making bricks, preparing glass-ceramics, producing aerated concrete, Portland cement, etc.
4. Mine filling
Using tailings to fill the mined areas of mines is one of the effective ways to directly use gold tailings. As a better filler, tailings can be used for local materials and waste utilization, eliminating the cost of collecting, crushing, and transporting the production of filler and crushed stone. For higher-value gold ore bodies, tailings can improve the extraction conditions of the pillars. Often, a proper amount of cement or other cementing materials is added to the filler to condense the loose tailings into a whole with a certain strength.
Land reclamation is also an effective way to treat gold mine tailings. Certain measures are taken on the gold mine tailings pond to plant agricultural, forestry, animal husbandry, and vital crops to conserve the soil and strengthen the embankment, which has a positive effect on protecting the environment and preventing pollution.