CO2干法压裂用支化硅氧烷及含氟聚合物类增稠剂研究现状与应用进展OA北大核心

CO2 dry fracturing technology,as a new waterless fracturing technique,has become an important research direction in tight oil and gas development in recent years.However,based on literature research,it is found that CO2 dry fracturing technology is not yet mature,mainly due to the low viscosity of liquid carbon dioxide or supercritical CO2,which leads to significant fluid loss and poor proppant carrying capacity.It requires thickening agents to significantly increase the viscosity of CO2.Considering the limitations of silicone-based thickeners that require a large amount of co-solvent and other thickeners with unsatisfactory thickening effects,as well as poor temperature and pressure adaptability,this paper provides an overview of the research progress on thickeners for CO2 fracturing fluids,focusing on branched silicone-based thickeners(with little or no co-solvent)and fluorinated thickeners from the perspectives of thickening mechanisms and thickening characteristics.In the thickening characteristics section,the structural and performance characteristics of these two types of thickeners are summarized.Additionally,the paper reviews the application of liquid CO2 and supercritical CO2 dry fracturing technology in China.Finally,the future research directions for CO2 thickeners and fracturing fluid systems in dry fracturing,including thickening mechanisms,thickening performance,and field applications,are discussed.