Analysis on technical points of water-preserving coal mining technical specifications

Water-preserving coal mining is an important part of green mining and one of the effective ways to solve the problems of coal mining,water resources and ecological environment protection in arid and semi-arid mining areas in Northwest China.In order to standardize the working ideas and methods of water-preserved coal mining,and to guide coal mining enterprises to protect the structure of aquifers while efficiently exploiting coal resources,the Shaanxi Provincial local standard Technical Specifications for Water-Preserving Coal Mining was formulated,stipulating the target layer of water resources protection in mining areas,geological work requirements,determination of the height of the water-conducting fissure zone,the main technology of water-preserving coal mining,and the outline of the technical verification report of water-preserving coal mining technology.Based on the detailed description of the development background of the Technical Specification for Water-Conserving Coal Mining,the relevant key points of the specification are further sorted out and explained:when coal seam mining changes the depth of the groundwater level,the maximum and minimum allowable depth must be met; in the process of coal seam mining,the flow of the mining area and surrounding rivers shall not be less than the minimum ecological water demand of the river; when mining 1-2,2-2 (No.3 coal seam in Yuheng mining area),3-1,4-2,5-2 coal seams in Jurassic coalfield in northern Shaanxi,the main target aquifers are Quaternary Sarawusu Formation aquifer,burnt rock aquifer and surface water bodies (lakes,reservoirs); When mining No.3 and No.4 coal seams in the Huanglong Jurassic coalfield,the main target aquifers are the Cretaceous Luohe Formation aquifer and surface water bodies (lakes,reservoirs); when coal seams No.5,10,and 11 are mined in the Northern Shaanxi Carboniferous Permian coal field,the main target aquifers include but not limited to Ordovician karst aquifers.The methods for determining the height of the water-conducting fissure zone mainly include detection method,empirical formula method,numerical simulation and similar simulation,etc.; Water-preserving coal mining technologies suitable for geological and ecological environmental conditions in Shaanxi Province include filling water-preserving coal mining technology,layered water-preserving coal mining technology,layered water-preserving coal mining technology and grouting water-preserving coal mining technology,etc.In order to accelerate the construction of ecological civilization in mines and realize green mining,the implementation of water-preserving coal mining technical specifications should be strengthened.