Meitan xuebao (Oct 2023)

Hydrodynamic field driving effect and mathematical model construction of water quality formation and evolution in coal mine

  • Yajun SUN,
  • Xianming ZHAO,
  • Zhimin XU,
  • Li ZHANG,
  • Ge CHEN,
  • Lin FENG,
  • Xin LI,
  • Tianci CHEN,
  • Huiqing YUAN,
  • Qi LIU,
  • Juan GUO,
  • Jian ZHANG,
  • Jiaxin LIU,
  • Xiaofeng XIONG

DOI
https://doi.org/10.13225/j.cnki.jccs.2023.0879
Journal volume & issue
Vol. 48, no. 11
pp. 4157 – 4170

Abstract

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The change of regional hydrodynamic field caused by coal mining process affects the multi-field process of the formation and evolution of mine water quality, which may lead to the pollution of the water environment in the coal mining area. Research on the driving mechanism of the hydrodynamic field and the method of quantitative calculation of key parameters is the premise of quantitative description on the multi-field effects of site pollution in the coal mining areas and its corresponding pollution control. Taking the Menkeqing Coal Mine as the geological background, this paper clarifies the evolution mechanism of the hydrodynamic field of goaf water. According to the difference in the flow path of the hydrodynamic field, it is divided into the stages of water level recovery and filling-up. It reveals the complex process of the formation and evolution of water quality in the goaf, with the hydrodynamic field as the main driving force, and the synergistic effects of multiple fields such as the hydrochemical field and the microbial field. Then the concept model of the water level recovery stage and filling-up stage and the theoretical calculation model of the analytical solution of the key parameters (permeability coefficient, water level, and water volume) of the hydrodynamic field are proposed. The measured data of the similar material simulation test and the three-dimensional box simulation test are compared with the model calculation results. The theoretical calculation of the permeability coefficient and the curve of goaf water level with time and the experimental measurement error are about 13.2% and 22.5%, respectively. The reliability of the theoretical calculation model is verified. Finally, on the basis of the equations of the hydrodynamic field, and the hydrochemical field and the microbial field under the influence of the hydrodynamic field in the goaf, a multi-field coupling effect model dominated by the hydrodynamic field is constructed. The constitutive model provides an inspiration for exploring the formation and evolution of coal mine water quality driven by the coupling of hydrodynamic field. This study supplements and expands the theory of coal mine water pollution prevention and control.

Keywords