Study on the factors that influence coal-water coordinated mining in deep coal seam mining areas

The ecological fragility of the Mu Us Sandy Land has become increasingly prominent during coal mining activities. Resolving the contradiction between regional coal resource development and water resource protection, as well as establishing a new pattern of green and high-quality development in mining areas are urgently needed. Considering the Huji'erte mining area of the Shendong coal base as the study area, based on the concept of green mining and using life cycle theory, the staged characteristics of the impact of the coal mining process on water resources are analysed and elaborated. Based on the current situation of coal-water resource development and utilization in deep coal seam mining areas, 23 key influential factors were extracted from six aspects, namely, hydrogeology, natural resources, mining impact, the ecological environment, coal mine disasters, and socioeconomics, to construct a coordinated coal-water co-mining impact index system for the deep coal seam mining area. Based on the Cone-Analytic Network Process (Cone-ANP) method optimized by cone-forming rules, a “multicone with a common bottom” model is proposed. The elements of the cone-top, cone-bottom, and common cone-bottom are determined based on the influential relationship between factors, and the analysis structure of “multicone with a common bottom” is constructed. The degree of action and the feedback relationships among the relevant factors were investigated. The weighting results obtained by the three methods, including the ANP method and the Cone-ANP method, were compared and analysed. The results of the study show that the weight proportion of the mining impact system is the highest, the coal mine disaster system is second, and the weight proportions decrease in the order of the ecological environment system, socioeconomic system, natural resource system and geological system. Under the joint action of various factors, the weights of the mine water inflow and mine water utilization rate are relatively high. The results of the study suggested that the source, generation and utilization processes of mine water should be on the focus to achieve the coordinated, green and high-quality development of coal-water in deep coal seam mining areas and to coordinate the health of the ecological environment and safe mine production. The supporting role of coal resources in the high-quality development of the local economy should be further strengthened, thus promoting the green and high-quality development of regional coal-water dual resources. The analysis and research conducted in this paper aim to explore a new path for the green and high-quality development of coal enrichment areas in the Mu Us Sandy Land and to provide a reference for the synergetic improvement of comprehensive coal-water benefits in coal enrichment areas.