Analysis of Natural Groundwater Flowing into the Flow Field of In Situ Leaching Mining

Abstract

This paper aims to quantitatively analyze the influence of natural groundwater flowing into the flow field of in situ leaching mining. The computational method was built to evaluate the effect of natural groundwater on the production efficiency of pumping wells for the in situ leaching of uranium, and the “flow ratio of groundwater” and related formulas were defined. C1 and C2 mining areas of an in situ leaching uranium mine in Inner Mongolia were taken as an example, and the effect on the “flow ratio of groundwater” when changing the flow quantity of injection wells and the position and length of the filter in the pumping and injection wells were compared. The results show that the variation in the “flow ratio of groundwater” of a whole mining area or a single pumping well in different production stages can be obtained by the neutral solution concentration value from the mining area’s numerical simulation. Regulating the position, length of the filter, and mode of fluid injection in an in situ leaching mine can control the quantity of natural groundwater flowing into the mining area and reduce the fluid exchange between the flow field of in situ leaching uranium mining and natural groundwater.

Reasonable Size Design and Influencing Factors Analysis of the Coal Pillar Dam of an Underground Reservoir in Daliuta Mine

“…It is not only affected by the pressure of overlying strata and water pressure, as there is also a strong weakening effect on coal pillar dams due to water intrusion [9,10]. In addition, the underground reservoirs of coal mines will affect the seepage flow of underground water, and the mine water will cause the creep of the coal body and influence its mechanical properties [11,12]. The research on coal pillar stability at home and abroad has mostly considered coal pillar stability in coal mine sections, and the research results included the limit equilibrium theory, etc.…”