A preliminary study on the eco-environmental geological issue of in-situ oil shale mining by a physical model

• Published in: Chemosphere (Oxford) Vol. 287; p. 131987
• Main Authors: Hu, Shuya, Wu, Hao, Liang, Xiujuan, Xiao, Changlai, Zhao, Quansheng, Cao, Yuqing, Han, Xiran
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-01-2022
• Subjects: In-situ pyrolysis; Oil shale; Scaled physical model; Underground environment; In-situ pyrolysis; Oil shale; Scaled physical model; Underground environment
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2021.131987

As traditional methods of oil shale production emitting high levels of pollutants, in-situ exploitation has aroused great concerns. In order to study the effect of in-situ pyrolysis products on the underground environment, an in-situ oil shale exploitation of underground environment impact laboratory simulation system was designed. Based on the hydrogeological condition of oil shale area in Nong'an City, a physical simulation test was conducted. It was found the temperature of surrounding layers continued to be perturbed after heating of the formation had stopped. The time during which the temperature was perturbed was about 4–5 times the heating period. During the simulation test, stray gas migration through fractures and faults was considered a mechanism for groundwater contamination. In the test, the maximum TOC content in aquifer was the value of 97.0 mg/L. The maximum total petroleum hydrocarbon (TPH) content of the simulated formation was 129 mg/kg after oil pyrolysis.
•A simulation system for in-situ exploitation of oil shale was developed.•The influence of in situ exploitation of oil shale on formation is revealed.•Oil shale exploitation effect on formation temperature field a last long time.•Gas from shale pyrolysis increased organic matter significantly in the upper formation.•An aquifer above the oil shale was significantly contaminated.