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Mining is a necessary process to retrieve the minerals and materials needed to keep the world functioning as we are accustomed. Coal and iron ore are among the top resources mined for by virtually every country in the world, making mining a major impact on the world's economy, ecology and health. With pressure on mining companies to produce more products while decreasing their costs, the quality for laborers sometimes suffers and workplaces become dangerous, increasing risk of injury and exposure to harmful toxins and allergens.

Coal is China's most important energy resources, its social and economic development play an extremely important role. Development and use of coal, both on plays a huge role in promoting socio-economic, but also had a significant impact on the environment. The development of coal gangue and coal-bed methane is the main waste generated in the process, the coal industry has long been regarded as hazardous substances and hazards of gas. Since the Third Plenum of the Eleventh Party, with the continuous deepening of economic reform and China's healthy and rapid development of industry and agriculture, in the case of energy increasingly scarce, people gradually realized that these wastes are still available for the use of side. Particularly in the last 20 years, the coal sector in the development and utilization of coal gangue and coal-bed methane has done a lot of exploration and production test achieved a number of achievements.

Practice has proved that as long as the changing concepts, scientific research, according to local conditions attention to development and coal production in the process of secondary use of mineral resources is not only entirely feasible, but has great potential; not only of harm into turning waste into treasure, and can save energy, and get major social and economic benefits. Coal gangue in the tunneling, mining and washing process of the solid waste discharges. Carbon quality, a mixture of clay and sandy shale, with low heat value. Carbon content of 20% ~ 30%, and some containing humic acid. China has accumulated over the years gangue about 1000Mt, and each year continues to emit about 100Mt, not only the accumulation of land, but also pollute the air or cause spontaneous combustion fire.

In recent years, with the various sectors of the comprehensive utilization of coal gangue awareness of the rapid rise of research, how to gangue turning waste into treasure? At home and abroad have been developed many ways to use. The basic principle is in identifying the nature of coal gangue based on the distinction so that the best use, and will use a variety of ways to combine the development of a certain scale and utilization system in order to get the best value for money. According to China's actual conditions, its use generally has five areas:

1. Underground coal mine filling. In the mining process of gradual reform, based on the use of coal gangue in the underground mined-out area, or directly to filling the ground after processing filling underground mined-out area.

2. Coal Mine Ground Subsidence Filling, reclaimed wasteland and pave the way for.

3. Coal gangue power generation. Containing carbonaceous more, the higher heat of gangue, can be used as fluidized bed and circulating fluidized bed power generation.

4. Production of coal gangue brick, cement and construction materials such as lightweight aggregate.

5. To extract sulfur from the coal gangue concentrate and other chemical products.

Extrusion type crushing machine mainly comprises rotary crusher, cone crusher, roll crusher and so on. Its working principle is: materials crushed by the extrusion, splitting and bending force between the crushing mechanism fixed tooth plate and the movable tooth plate. This kind of crusher mixedly crush materials in the crushing cavity, which is vulnerable to the formation of pulverization and easy to form the big shape product, which can't ensure product particle size and with a large power consumption. This kind of crusher is mainly used for crushing hard materials in metal, mining, gravel field and other industries.