油页岩热破裂规律分形理论研究

THEORETICAL RESEARCH ON THERMAL CRACKING FRACTALS LAWS OF OIL SHALE

以不同温度下油页岩破裂显微CT图片作为分析对象,将分形的基本理论运用到油页岩的热破裂过程中。研究边长为7.0mm正方体油页岩试件在200℃～600℃范围内热破裂裂隙分布的分形规律,得到不同温度下热裂隙分布的分形维数和分布初值。研究结果表明:不同温度下油页岩内部裂隙的分布具有很强的自相似性,符合分形规律,分形维数为1.0～1.5。建立分形维数、分布初值与温度的关系,从分形理论上研究油页岩的热破裂过程,宏观量化裂隙的分布状况和复杂程度。研究结论对分析油页岩热解过程中"微渗流通道"的发展演化过程具有重要的意义;同时,为从分形的角度探索其他岩石的热破裂过程提供一种新的方法和思路。

The oil shale thermal cracking CT images under different temperatures are considered as the analytical objects; and the basic theories of fractals to the thermal cracking procedure of oil shale are applied for the first time. The distribution laws of the thermal fissures within the range of 200 ℃ - 600 ℃ of oil shale square body of 7.0 mm in length are researched;and the fractals dimensions and initial distribution values of the fissures under different temperatures are obtained. The achieved results show that the thermal fissures have strong self-similarity according with fractals laws, and the values of fractal dimensions are ranged from 1.0 to 1.5. The relationship between fractals dimensions, initial distribution values and temperatures is established. With fractals theory, the thermal cracking procedure of the oil shale, distribution state and complexity of the fissures are analyzed. The derived conclusions for analyzing the evolution of micro-seepage channels in the oil shale pyrolysis have important references; and at the same time, a new method and certain ideas for thermal cracking procedure of other rocks with fractals theory are offered.