I. Tailings Gravity Separation Process Although the content of useful components in tailings is relatively low, using advanced technology and reasonable process for tailings gravity separation can also recover the useful components in tailings to a greater extent, so that resources can be fully recovered, the output of final tailings can be reduced, and the pressure of tailings on the environment can be alleviated. At present, the common tailings re-concentration processes are as follows:
1. tailings containing minerals (such as pyrolusite, zinc oxide and apatite) are treated by flotation process.
Due to the development of new reagents and new processes, tailings produced by some simple processes, especially old tailings, can be recycled through flotation and re-concentration.
2. Recovery of fine minerals from tailings by new gravity separation equipment.
Many traditional new gravity separation equipment, after being invented and perfected, can be applied to the gravity separation of fine and ultrafine tailings, such as vertical centrifugal concentrator, composite force field vibrating screen, composite force field centrifuge and so on.
3. Using microbial treatment and leaching technology to treat tailings.
This technology mainly uses the biochemical action of microorganisms to improve the properties of tailings, and extracts harmful metal ions from tailings through microbial leaching or microbial mineralization to avoid environmental pollution.
Second, the tailings dewatering process in the separation stage, the pulp often contains a lot of water, and the high water content of tailings is likely to lead to dam-break accidents. Therefore, tailings concentration and dehydration is also one of the important links in concentrator. Common tailings dewatering processes include:
1, concentration process with hydrocyclone as the core
As a kind of equipment for solid-liquid separation by centrifugal force, hydrocyclone has the characteristics of small floor space and high underflow concentration. This concentration process mainly uses hydrocyclone and thickener to form a series or closed-circuit process to obtain high-concentration concentrated products.
2、? Tailings filter pressing process using filter press
In the treatment of gold mine tailings, pressure filtration dehydration is widely used. This method has the characteristics of low water content in filter cake and recyclable filtrate, but the single machine treatment capacity is low, so it is difficult to dehydrate large mineral processing tailings alone.
3. Dry discharge of tailings
Tailings dry discharge is a new technology using patented equipment such as dewatering cyclone, high-efficiency high-frequency dewatering screen and high-efficiency deep cone thickener, which can reduce the moisture in tailings to below 15%, save costs and effectively avoid environmental pollution.
Three. Filling mined-out area with tailings Filling mined-out area with tailings is to use tailings waste and backfill it into mined-out area after treatment, which can protect the landform and reduce the cost of tailings dam. At present, there are two main methods to fill mined-out areas with tailings:
1, full tailings cemented filling technology
Cement and fly ash are mixed with dehydrated tailings in the cemented filling of all tailings. Filling aggregate is formed, and the filling slurry is transported to the mining and filling area to fill the goaf by gravity through the pipeline.
2. Full tailings filling technology with high water consolidation.
High-water consolidated full tailings filling is similar to full tailings cemented filling, but the difference is that high-water material is used instead of cement as cementing material. In this method, A material mainly composed of aluminate and sulphoaluminate and B material mainly composed of anhydrite, quicklime and coagulant are used for pulping and conveying respectively, and they are mixed before filling, which has the characteristics of fast setting speed.
The above three aspects are the three directions of tailings treatment, which need to be determined according to the scale and investment of concentrator in practical application. It is suggested to consult the concentrator equipment supplier with concentrator research and design qualification and choose the tailings treatment technology suitable for concentrator.
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