The amount of mining solid waste generated is huge, and mining solid waste has a significant impact on the environment and human health. But there is no absolute garbage in the world; there are only resources that have been misplaced. With the advancement of technology, mining solid waste is increasingly being utilized by humans as a resource that is easy to obtain, has wide utilization channels and good economic benefits.
Mining solid waste mainly includes mining waste rocks and tailings. Waste rock refers to various surrounding rocks stripped from the main ore during the mining process of various metal and non-metal mines. Tailings refer to the remaining tailings after extracting concentrate in the beneficiation process. So, what are the ways to make effective use of these “misplaced resources”?
- Recycle valuable elements
In the early days of the mining industry’s development, due to the limitations of smelting technology conditions, many tailings contained a large amount of valuable metal elements such as iron and copper, as well as non-metal elements such as sulfur. Moreover, since the tailings have been ground finely, the costs of mining, crushing and grinding can also be saved. Therefore, the recovery of valuable elements in the tailings has significant social and economic benefits.
- Prepare sand and gravel aggregates
Sand and gravel aggregates are the most widely used, indispensable and irreplaceable basic materials in infrastructure projects such as buildings, roads and Bridges. However, sand and gravel aggregates are non-renewable resources. Thousands of years of mining have caused great damage to the Earth’s environment. In China’s metal and non-metallic mineral industry, during the long-term mining and production process, a large amount of waste rock and tailings are generated in mines. These tailings resources can completely or partially replace sand and gravel aggregates.
- Prepare cement
The basic raw materials of cement are limestone and clay ore. Limestone and clay rocks (such as shale) are common waste rocks in mines, or tailings containing corresponding components can also be used as basic raw materials. Some tailings are also suitable for use as admixtures for cement. Adding an appropriate amount of admixtures to cement can not only improve certain properties of the cement but also save the consumption of basic materials. For instance, waste rocks (or tailings) with a relatively high content of amorphous substances, such as glassy volcanic rocks, tuff, and pumice, can also be used as active admixtures.
- Used as filling material
Filling the underground goated-out areas of mines with high-concentration tailings and cementitious materials to make high water-rapid setting materials can not only utilize local materials to resource the solid waste of mines, but also significantly reduce the amount of tailings stored on the ground, save land acquisition costs and investment in tailings facility construction, and lower a series of safety hazards caused by the construction of tailings ponds. Alleviating pollution to the surrounding environment and damage to the original ecology, avoiding the waste of land resources, and promoting the construction of a conservation-oriented and environmentally friendly society.
