Application of “water release cross section flow” method in mine water inflow prediction——Taking Hetaoyu Coal mine in the southern margin of Ordos Basin as an example

The focus of coal production in China is gradually moving westward, and the western Ordos Basin is facing not only the shortage of water resources, but also the serious threat of mine water disaster. In the process of coal mining, accurate and dynamic prediction of mine water inflow is the key to prevent mine water inflow accidents. At present, some of the most commonly used prediction methods of mine water inflow, such as water balance method, analytical method, correlation analysis method, hydrogeological analogy method, etc., have large prediction errors due to their limitations. In the previous study, the author’s team found that the water gushing in the mine is usually superposed by the water release from the spalling-binary structure itself and the water release from the symmetrical section around the outer boundary. The duration of the water release (natural drainage of the spalling-aquifer) is relatively short, and it occurs periodically with the spalling-roof and is intermittent. The boundary crossing section is usually continuous. The direct upward development of No. 8 coal drainage fracture zone in Hetaoyu Coal Mine can lead to confined water flooding into the mine and become the main threat to mine water flooding. In order to accurately and dynamically predict the mine water inflow, based on the “water-release - cross section flow” formula derived from the previous research of the author’s team, the dynamic prediction of mine water inflow in Hetaoyu Coal mine in the south of Ordos Basin is carried out according to the fracture law of the roof strata, taking full account of the characteristics of mine mining and roof overburden movement. Compared with the measured water inflow, the relative error of the predicted results is 11%～23%, which is significantly higher than that of the traditional analytical method. It provides the method basis for the dynamic prediction of mine water inflow in different stages of mining, and provides the basis for the work of mine water prevention and control and reasonable installation of anti-drainage facilities. © 2023 Coal Science and Technology. All rights reserved.