Tailings are solid waste discharged after the mineral processing plant crushes the ore and selects “useful components” under specific technical conditions. How to rationally and comprehensively utilize tailings has gradually become one of the issues that attach great importance to.

On the one hand, tailings storage not only occupies a large amount of land and easily causes environmental pollution, but is also a huge safety hazard. On the other hand, tailings contain huge secondary development and utilization value, including various non-ferrous metals, ferrous metals and non-metallic minerals. The comprehensive utilization of tailings is one of the main directions for future mining development, and the country has also issued A range of policies are encouraging a development focus.

The comprehensive utilization of tailings needs to be determined according to its category. In addition to conventional treatment methods such as building materials, soil improvement and underground filling, China currently focuses more on the re-selection and intensive processing of tailings in order to achieve high added value of the tailings. Comprehensive utilization.

1. Purification method of tailings re-selection

The recovery of valuable components in tailings includes not only the original beneficiation purpose components and associated components that remain in the tailings, but also new valuable components that have not been identified or discovered. The recovery of valuable components can be achieved by improving the process flow and mineral processing equipment on the basis of the original mineral processing equipment. Sometimes it is also necessary to establish a secondary processing plant to recycle with new processes and equipment.

In the re-selection of tailings, commonly used purification methods include gravity separation, magnetic separation, flotation and microbial treatment. Among them, the flotation process is often used as the main method of re-selection of tailings. After flotation and re-selection, not only can High-quality concentrate products can significantly reduce the output of final tailings and reduce the pressure of tailings on the environment. For example:

There is quartz associated with the raw kaolin ore, and this part of the associated quartz ore is treated as tailings along with the production of kaolin. After scrubbing, grinding, screening, gravity separation, magnetic separation and flotation treatment of kaolin tailings, high-quality quartz sand products can finally be obtained.

2. Deep processing of tailings re-selection products

The deep processing of tailings reprocessing products includes not only preparing them into various functional materials, composite materials, optical products, glass products, etc., but also including overall utilization products of tailings without reprocessing value. According to the chemical composition and particle size of the tailings Properties, etc., to manufacture high value-added flocculants, crystallized glass, daily ceramics, etc. For example:

For some domestic low-iron quartz sand tailings, electrical and electronic grade silicon powder that meets the requirements can be prepared through purification processes such as “magnetic separation-scrubbing-desliming-flotation”.

Ceramic glass decoration material is one of the high-end building decoration materials. It has the characteristics of high strength, wear resistance, high gloss, no color difference, and can be colored at will. The tailings suitable for making glass-ceramics are high-silicon and low-iron tailings, preferably containing a certain amount of alkali metals, such as the tailings of some kaolin mines, gold mines, and tungsten mines.

Tailings reprocessing is an inevitable choice under the current background of increasing shortage of mining resources. However, due to different industry uses, various types of tailings also have different characteristics and utilization values. Therefore, during the tailings treatment process, it is necessary to clarify the characteristics of the tailings. Based on the potential value, targeted development and utilization can ensure that the role of mine tailings can be maximized.