基于三维CT图像的油页岩热解和内部结构变化特征分析_赵静.pdf

33 1 Vol.33 No.1 2014 1 Chinese Journal of Rock Mechanics and Engineering Jan.2014 CT ( 030024) CT CT (1) 20 600 (2) 100 200 2 600 39.80% 97.45% CT TU 45 A 2014 STUDY OF PYROLYSIS AND INTERNAL STRUCTURAL VARIATION OF OIL SHALE BASED ON 3D CT IMAGES ZHAO JingFENG ZengchaoYANG DongKANG Zhiqin (Institute of Mining TechnologyTaiyuan University of TechnologyTaiyuanShanxi 030024China) Abstract A micro-CT experimental system was used to scan a specimen of oil shale subjected to pyrolysis at different temperatures. From 3D CT images based on X-ray attenuation coefficientsthe evolution of pores and cracks in the specimen was analyzed at different stages of pyrolysis. The results show that (1) From 20 to 600 the specimen is transformed from a compact state to a porous medium. (2) At the higher temperaturesincreasing numbers of voids become interconnected. At 100 the voids are restricted to a very small region but as the temperature is raised to 200 channels for oil and gas seepage are formed within the study region. At 600 the pyrolysis rate of the specimen is calculated to reach 39.80% and the largest void is 97.45% of all the voids. All voids are interconnected into one large voidforming a channel for the seepage of oil and gas running through the entire X-rayed region. The study conclusions are of great significance for discovering how the channels for oil and gas seepage developing during in-situ pyrolysis of oil shale. Key words rock mechanics micro-CT oil sha