Study on status quo and development as well as utilization of coal resources “underbuildings,water bodies, railways and above confined water”in North China Coalfields

With the increase of coal mining years in North China, shallow coal resources are becoming less and less, and there is a phenomenon of resource depletion in some areas. The development and utilization of coal resources “under buildings,water bodies, railwaysand above confined water” in resource exhausted mines can effectively extend the service life of the mines. In order to make rational use of the coal resources in the economically developed areas of North China, the distribution characteristics of coal resources in Shanxi, Hebei, Shandong, Henan and Anhui provinces were basically figured out by analyzing and studying the geological and hydrogeological data of coal fields, remote sensing interpretation technology and water inrush coefficient method of coal seam floor.The coverage areas“under buildings,water bodies and railways” are 21 819.27 km2, It is estimated that the coal resources “under buildings,water bodies and railways” are about 47.415 billion tons, accounting for 12.10% of the total resources. Among them, the coal resources under buildings are approximately 43.125 billion tons, coal resources under railways are approximately 1.286 billion tons,and coal resources under water bodies are approximately 3.004 billion tons. It is estimated that the coal resources above confined water are about 95.426 billion tons, accounting for 24.35% of the total resources. Among them, the buried depth is about 169 million tonsbelow 600 m, the burial depth is about 31.166 billion tons in the depth of 600～1 000 m, and about 64.091 billion tons in the depth of 1 000～1 500 m.Through the research on the technology of coal resource development and utilization in “under buildings,water bodies, railways,and above confined water”, it is believed that the technologies of reducing subsidence and harm are the most effective technical means of coal resource development and utilization in “under buildings,water bodies, railwaysand above confined water”. The main factors restricting the development and utilization of coal resources, such as cost, material and technology were analyzed. Finally, it is pointed out that with the application of new filling technology and mining technology, a large amount of coal resources“under buildings,water bodies, railways and above confined water” can be developed and utilized.