Experimental investigation on the physical and mechanical properties deterioration of oil shale subjected to freeze-thaw
- PDF / 11,409,284 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 51 Downloads / 236 Views
ORIGINAL PAPER
Experimental investigation on the physical and mechanical properties deterioration of oil shale subjected to freeze-thaw cycles Hong-chao Zhao 1 & Xiao-lei Zhang 1 & Gang Han 2 & Hui Chen 1 Received: 1 October 2018 / Accepted: 10 July 2019 # Saudi Society for Geosciences 2019
Abstract The exploration and utilization of oil shale have drawn much attention during the past decades around the world. To better understand the mechanical behavior of oil shale in the Junggar Basin, northwestern China, laboratory tests were conducted on five series of oil shale samples collected from different sites to investigate the effect of water on deteriorated rocks due to freezethaw weathering. The petrographic analysis and geochemical analysis were carried out, followed by the freezing-thaw (F-T) cycle test ranged from 10 times to 40 times with the increase of 15 times. All samples were frozen in a temperature-controlled freeze cabinet at − 20 °C and then thawed in distilled water at 20 °C. The deterioration of the samples was explored by the observation of the loss of weight and decrease of uniaxial compressive strength through some typical technical methods including scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis on the selected samples. Experimental results show that the uniaxial compressive strength is significantly affected by the increase of F-T cycles. The test results also indicate that the microstructure, in particular the minor cracks, is one of the main factors controlling the deterioration procedure of oil shale subjected to F-T cycles. Keywords Oil shale . Freeze-thaw cycles . Microstructure . Junggar Basin
Introduction In recent years, the exploration and development of oil shale have drawn much attention around the world due to its large reservation and cost-effectiveness (Dyni 2006; Fu et al. 2009). More than 700 billion tons of oil shale have been explored in China (Li 2012; Tao et al. 2016; Zhao et al. 2012), equivalent to 62% of the conventional petroleum resources. As one of the largest oil basins, there are over 120 billion tons oil shale distributed in Junggar Basin, northwestern China (Carroll et al. 1992; Yang et al. 2018). Different from other mineral
Editorial handling: Liang Xiao * Hong-chao Zhao [email protected] 1
School of Geological and Mining Engineering, Xinjiang University, Urumqi, Xinjiang 830046, China
2
Xinjiang Baoming Mining Co., Ltd., Changji, Xinjiang 831700, China
areas, the use of open-cut mining is accepted as the costeffective mining method due to its shallow depth (i.e., within 200 m). However, the unique geological conditions such as high altitude and seasonal freeze-thaw (F-T) cycles have led to various challenges affecting the stability of the slip of opencut. In particular, the regional climate characterized with high temperature difference (e.g., − 16 °C in winter and 29 °C in summer) and long duration of freezing has been regarded as the main reason for the deterioration of oil shale, resulting in the occurrence of some unexpected disast
Data Loading...
