1 green coal mining system The basic concept of coal mining green mining and corresponding green mining technology is to understand and treat all kinds of resources that can be utilized, such as coal, gas and water, from the perspective of general resources. The basic starting point for green mining of coal is to prevent or minimize the adverse effects of mining coal on the environment and other resources. The goal is to achieve the best economic and social benefits. According to the land, groundwater, gas and meteorite emissions in coal mines, green mining mainly includes the following contents: water resources protection - "water conservation"; gas drainage - "coal and gas mining"; land and building protection - "filling mining" "The discharge of meteorites occupies the land to pollute the environment - "underground coal gasification" and so on. In 2003, Academician Qian Minggao of China University of Mining and Technology first proposed the concept and technical system of green mining in coal mines, and then defined the research objectives of green mining to achieve coordinated development of coal resource exploitation and environmental protection, pointing out the direction for the study of green mining technology in China. . The green mining technology system proposed by the academician Qian, the theoretical basis of green mining: (1) the key layer theory. (2) The influence of mining on rock movement and the law of movement. (3) The law of seepage of water in cracked rock mass. (4) The development of joint fissures in the rock strata after mining. 2 Water conservation mining Water-retaining coal mining has different technical connotations in different mining areas. Water-deficient mining areas should be mainly protected and utilized by water resources; large-water mining areas should focus on reducing water resources damage and preventing water disasters. Therefore, water conservation includes a number of important contents such as water resources protection, water resource utilization (coal and water co-production) and water disaster prevention. During the coal mining process, the original runoff of the underground aquifer was destroyed, and the groundwater was discharged in large quantities; the water-conducting fissure zone above the goaf and the groundwater body penetrated to form a large-scale groundwater falling funnel, which caused the water level of the regional aquifer to decline, directly affecting the regional hydrogeology. condition. The surface subsidence caused by the impact of mining after mining often affects the original form of surface water bodies (rivers, lakes, wells, etc.), causing some of the ditch springs to reduce or even dry up; affecting the normal production and life of local residents, and thus affecting regional vegetation growth, Even the land is desertified. Most of China's mining areas are located in arid and semi-arid areas, and coal mining destroys 2.2 billion m3 of groundwater every year. It can be seen that water conservation is of great significance. 3 Coal and gas mining Gas is both a harmful gas in mines and a clean energy source. Therefore, it should be resourced, and its technical approaches are: (1) Pre-harvest extraction: If the gas in the coal seam can be extracted before mining, it is the best way to use gas to improve coal mine safety. However, due to the low gas permeability of most coal bodies in China, it is difficult to extract gas in this layer. (2) Coal and gas co-production: After mining, the surrounding rock pressure is reduced, and a large amount of gas is released in the goaf, which is conducive to gas drainage, thus forming a coal and gas co-production system. (3) Abandoned mines to extract gas. In view of the fact that the abandoned coal seam is filled with gas after mining, the distribution and drilling of the fracture field in the rock after mining can be utilized, and the gas drainage pipe is installed in the well and the well is closed to extract the gas. (4) Returning wind wells to recover gas. (5) The technologies of coal and gas mining are mainly: drilling method for roadway and pressure relief method. 4 filling mining The majority of our coal mines at the presence of buildings, bodies of water, the problem of coal under pressure Railway, filling method is of great significance to solve such problems. The filling mining method is a rock formation control method for filling a goaf of a coal mining face with a filling material. The method can alleviate the mine pressure generated by the supporting pressure of the working face, improve the maintenance condition of the stope and roadway, effectively reduce the surface subsidence and deformation, improve the mining rate of the coal mine, and protect the ground buildings, structures, ecological environment and water bodies. Pvc Twinwall Panel,Decorative Wall Panels,Pvc Decorative Panels,Outdoor Decorative Panels PINGYUN INTERNATIONAL , https://www.pingyunconstruction.com