矿业科学学报2024，Vol.9Issue(3)：342-350,9.DOI:10.19606/j.cnki.jmst.2024.03.003
基于CT扫描的CO2相变致裂煤裂隙演化特征
Evolution characteristics on coal fractures induced with CO2 phase transition fracturing based on CT scanning
摘要
Abstract
This study conducted the CO2-PTF coal experiment to further reveal the fracturing transfor-mation mechanism of CO2 phase transition fracturing(CO2-PTF)coal.According to the CT scanning and 3 D fracture reconstruction,we analyzed the fracture structure parameters of coal before and after CO2-PTF,and clarified the evolution characteristics of the three-dimensional fracture structure of coal induced by CO2-PTF.The research results indicated that after CO2-PTF,the total number of fractures in the coal sample decreased,while the total volume and surface area of fractures increased.The CO2-PTF generated fracture expansion and transformation effects where the small-scale fractures were ex-panded and transformed into larger scale fractures under the CO2-PTF pressure.The number,volume,and surface area of fractures of less than 1 000 μm in length were significantly reduced,while the vol-ume and surface area of fractures of longer than 1 000 μm in length were significantly increased.The expansion and connection between fractures caused a decrease in their quantity.CO2-PTF improves the connectivity of the three-dimensional fracture in coal and is conducive to gas migration and produc-tion.This study offers new insights into and evaluation method for the effect of CO2-PTF,and could provide references for the research on fracture evolution characteristics in other unconventional natural gas reservoirs and their modifications.关键词
CO2相变致裂/CT扫描/煤储层/三维裂隙演化Key words
CO2 phase transition fracturing/CT scanning/coal reservoir/three dimensional fracture evo-lution分类
矿业与冶金引用本文复制引用
刘高峰,关文博,张震,李宝林,刘欢,司念..基于CT扫描的CO2相变致裂煤裂隙演化特征[J].矿业科学学报,2024,9(3):342-350,9.基金项目
国家自然科学基金(42230814,42372204) （42230814,42372204）
河南省高等学校重点科研项目(24B170005) （24B170005）
河南省科技攻关项目(242102320365) （242102320365）
