Quantitative analysis of microscopic pore structure and fluid simulation of supergene gypsum minerals in a uranium mine
ZHOU Lei1, XI Xiangyu2, ZHOU Lin3, DAI Qunwei1, HAN Ying2, DONG Faqin*1,3
1. Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory,Southwest University of Science and Technology,Mianyang 621010,China; 2. School of Life Science and Engineering,Southwest University of Science and Technology,Mianyang 621010,China; 3. Key Laboratory of Solid Waste Treatment and the Resource Recycle, School of Environment and Resource,Southwest University of Science and Technology,Mianyang 621010,China
Abstract：The morphological structure and conductivity characteristics of natural rock pores and fractures are of great significance for mining,beneficiation,metallurgy,petroleum engineering,carbon sequestration,water pollution control,and nuclear waste/hazardous material isolation.A series of key pore structure parameters such as pore radius,pore distribution,throat radius,connectivity and permeability of the surface gypsum mineral microstructure in a uranium mining area were quantitatively characterized by X-ray computed microtomography through data acquisition,data reconstruction,data volume cutting,algorithm analysis and seepage simulation.The pore radius of the surface gypsum in the mining area is mainly concentrated in the range of 5.0-40.0 μm.Nearly 90% of the pores are connected with one throat, and the average pore throat ratio is about 1.33.The throat radius and pore radius are in the same order of magnitude,and the pore throat radius ratio is not large.The pore space development is relatively uniform,and the pore section and throat section are mainly triangular.When the inlet pressure is 0.5 MPa,the seepage velocity of single-phase water is the same in X,Y and Z directions,and the absolute permeability is close to zero.
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