School of Mines, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, China.
School of Energy and Mining, China University of Mining and Technology (Beijing), Beijing, 100083, China.
Environ Sci Pollut Res Int. 2024 Mar;31(14):21442-21457. doi: 10.1007/s11356-024-32570-0. Epub 2024 Feb 23.
Water-rock interaction mechanism and water purification capacity of broken coal and rock masses are very important for the efficient operation of the underground reservoir. In this paper, a water purification simulation device for an underground mine reservoir was designed. The experimental study on the dynamic interaction between broken coal and rock masses and mine water was carried out. The water purification mechanism is analyzed from the changes in rock mineral composition and mine water quality before and after the test. The results show that after the broken coal and rock mass purification, the water turbidity and the concentration of chlorides and suspended solids decreased obviously. The water purification capacities of mudstone and sandstone are stronger than that of coal samples. After 60 days of reaction between the working face sewage and the broken samples (mudstone, sandstone, and coal), the turbidity, chromaticity, and residual chlorine decreased by > 90%, 90%, and 60%, respectively; and COD decreased by 35.29%, 30.59%, and 28.99%, respectively. While the TDS and the total hardness increased by about 40%, 30%, and 10% for the mudstone, sandstone, and coal, respectively. It shows that coal also has the worst degradation performance. The water purification effect of broken coal and rock masses has a significant time effect. The early stage of water-rock interaction is dominated by mineral dissolution, and the middle stage is dominated by precipitation and adsorption. The pH value of the solution has a certain influence on the ion change. In the later stage, the water-rock interaction is weak in a dynamic equilibrium state, and the change in the mine water quality index is not obvious. Considering the influence of rock lithology on water quality and the law of water-rock interaction time, the construction site selection and water storage time optimization of underground reservoirs in Jinjie Coal Mine were carried out, respectively.
破碎煤岩体的水岩相互作用机制及水体净化能力对地下水库的高效运行非常重要。本文设计了一种地下矿山水库水净化模拟装置，对破碎煤岩体与矿井水的动态相互作用进行了实验研究。从试验前后岩矿组成变化和矿井水质变化分析了水的净化机理。结果表明，破碎煤岩体净化后，水的浊度和氯化物、悬浮物浓度明显降低。泥岩和砂岩的水体净化能力强于煤样。工作面污水与破碎样品（泥岩、砂岩和煤）反应 60 天后，浊度、色度和残余氯分别降低了>90%、90%和 60%；COD 分别降低了 35.29%、30.59%和 28.99%。而 TDS 和总硬度分别增加了约 40%、30%和 10%泥岩、砂岩和煤。这表明煤也具有最差的降解性能。破碎煤岩体的水体净化效果具有显著的时间效应。水岩相互作用的早期以矿物溶解为主，中期以沉淀和吸附为主。溶液的 pH 值对离子变化有一定影响。在后期，水岩相互作用处于动态平衡状态较弱，矿井水质指标变化不明显。考虑到岩性对水质的影响和水岩相互作用时间规律，分别对金杰煤矿地下水库的建设场地选择和蓄水时间进行了优化。
