The chemical damage of sandstone after sulfuric acid-rock reactions with different duration times and its influence on the impact mechanical behaviour
Qinghe Niu,
Mingwei Hu,
Jiabin He,
Bo Zhang,
Xuebin Su,
Lixin Zhao,
Jienan Pan,
Zhenzhi Wang,
Zhigang Du,
Yuebei Wei
Affiliations
Qinghe Niu
Key Laboratory of Roads and Railway Engineering Safety Control (Shijiazhuang Tiedao University), Ministry of Education, Shijiazhuang, 050043, China; Liaoning Qingchuang High Tech Construction Industrialization Consulting Co., Ltd, Shenyang, 110179, China; Hebei Technology and Innovation Center on Safe and Efficient Mining of Metal Mines, Shijiazhuang, 050043, China
Mingwei Hu
Key Laboratory of Roads and Railway Engineering Safety Control (Shijiazhuang Tiedao University), Ministry of Education, Shijiazhuang, 050043, China; Liaoning Qingchuang High Tech Construction Industrialization Consulting Co., Ltd, Shenyang, 110179, China; Hebei Technology and Innovation Center on Safe and Efficient Mining of Metal Mines, Shijiazhuang, 050043, China
Jiabin He
Key Laboratory of Roads and Railway Engineering Safety Control (Shijiazhuang Tiedao University), Ministry of Education, Shijiazhuang, 050043, China; Liaoning Qingchuang High Tech Construction Industrialization Consulting Co., Ltd, Shenyang, 110179, China; Hebei Technology and Innovation Center on Safe and Efficient Mining of Metal Mines, Shijiazhuang, 050043, China
Bo Zhang
Key Laboratory of Roads and Railway Engineering Safety Control (Shijiazhuang Tiedao University), Ministry of Education, Shijiazhuang, 050043, China; Liaoning Qingchuang High Tech Construction Industrialization Consulting Co., Ltd, Shenyang, 110179, China; Hebei Technology and Innovation Center on Safe and Efficient Mining of Metal Mines, Shijiazhuang, 050043, China; Corresponding author. State Hebei Technology and Innovation Center on Safe and Efficient Mining of Metal Mines, Shijiazhuang, 050043, China.
Xuebin Su
Beijing Research Institute of Chemical Engineering and Metallurgy, Beijing 101149, China
Lixin Zhao
Beijing Research Institute of Chemical Engineering and Metallurgy, Beijing 101149, China
Jienan Pan
School of Resources & Environment, Henan Polytechnic University, Jiaozuo 454000, China
Zhenzhi Wang
School of Resources & Environment, Henan Polytechnic University, Jiaozuo 454000, China
Zhigang Du
School of Civil Engineering, Luoyang Institute of Science and Technology, Luoyang, Henan, 471023, China
Yuebei Wei
Key Laboratory of Roads and Railway Engineering Safety Control (Shijiazhuang Tiedao University), Ministry of Education, Shijiazhuang, 050043, China; Liaoning Qingchuang High Tech Construction Industrialization Consulting Co., Ltd, Shenyang, 110179, China; Hebei Technology and Innovation Center on Safe and Efficient Mining of Metal Mines, Shijiazhuang, 050043, China
The low-permeability characteristic of sandstone-type uranium deposits has become the key geological bottleneck during the in-situ leaching mining, seriously restricting the development and utilization of uranium resources in China. At present, the blasting-enhanced permeability (BEP) and acidizing-enhanced permeability (AEP) are confirmed to be mainstream approaches to enhance the reservoir permeability of low-permeability sandstone-type uranium deposit (LPSUD). To clarify the synergistic effect of BEP and AEP, the acid-rock reaction and dynamic impact experiments were conducted, aiming to study the effect of chemical reactions on pore structure, dynamic mechanical properties and failure pattern of sandstone. Results show that with the increasing acid-rock reaction time, the total pore volume of samples is promoted largely and exhibits obvious chemical damage. The change of pore volume depends on the pore size, the 100–1000 nm and 1000–10000 nm pores are more susceptible to acid-rock reactions. The dynamic peak strength and the dynamic elastic modulus are decreased and the dynamic peak strain and strain rate are increased when lengthening the acid-rock reaction time, whose evolution laws can be fitted by the logistic expression, the linear expression and the exponential expression, respectively. The acid-rock reactions also have an influence on the fracture development of samples after the dynamic impact. The damaged fractures on the end faces of samples grow from the isolated short fracture, the isolated long fracture to the fracture network, and the damaged fractures on the sides of samples develop from the non-penetration fractures, penetration fractures to the multi-branch fractures. This study clarifies the physical and chemical combined damage mechanism, demonstrates the potential of reservoir stimulation by uniting the BEP and the AEP, and provides a theoretical reference for the reservoir stimulation of LPSUD.
