THE SUPERCRITICAL CO₂ FRACTURING MECHANISIM AND ADVANTAGES ANALYSIS OF SHALE

Supercritical carbon dioxide(CO₂) is a promising non-aqueous fracturing fluid compared to the water regularly used in hydraulic fracturing operations. It has great potential for improving shale reservoir production. In this study, the characteristics of supercritical CO₂ fracturing were summarized, and the effects of CO₂ viscosity and energy changes on fracturing were analyzed. Additionally, the advantages of supercritical CO₂ fracturing compared to water fracturing were revealed. The results show that supercritical CO₂ fracturing has the advantages of sustainability and high efficiency. All shale specimens fractured by supercritical CO₂ show smaller breakdown pressure. The shale fractures induced by supercritical CO₂ have the characteristics of simple but larger width, thin but complex. These results are of great significance for understanding the mechanism and advantages of supercritical carbon dioxide fracturing and provide references for the green development of shale reservoir fracturing.