水基钻井液用耐高温凝胶堵漏剂的制备与评价

Preparation and Evaluation of High Temperature Resistant Gel Plugging Agent for Water-based Drilling Fluid

以丙烯酰胺、2-丙烯酰胺基-2-甲基丙磺酸和乙烯基吡咯烷酮为耐高温凝胶的单体,引发剂优选过硫酸钾和亚硫酸氢钠,交联剂优选N,N'-亚甲基双丙烯酰胺,合成方法选择水溶液聚合法,制备了一种水基钻井液用耐高温凝胶堵漏剂。采用红外光谱分析、核磁共振分析和热重分析对耐高温凝胶的分子结构和抗温能力进行了表征。采用高温高压失水仪和长裂缝堵漏评价实验装置对耐高温凝胶的渗透型漏失堵漏效果和裂缝型漏失堵漏效果进行了评价。当温度为150℃时,耐高温凝胶堵漏剂对渗透型漏失堵漏效果可达7 MPa,对2×1 mm裂缝的漏失堵漏效果可达1.88 MPa。

A high-temperature-resistant gel plugging agent for water-based drilling fluids was prepared by using acrylamide,2-acrylamido-2-methylpropanesulfonic acid and vinylpyrrolidone as the monomers,the initiators preferred to be potassium persulfate and sodium bisulfite,the cross-linking agent preferred to be N,N'-methylene bis-acrylamide,and the synthesis method selected to be the aqueous solution polymerization method.The molecular structure and temperature resistance of the high-temperature-resistant gel were characterized using infrared spectral analysis,nuclear magnetic resonance analysis and thermogravimetric analysis.The permeability lost plugging effect and fracture lost plugging effect of the high temperature resistant gel were evaluated using a high temperature and high pressure water loss meter and a long fracture plugging evaluation experimental device.When the temperature is 150℃,the high-temperature-resistant gel lost plugging agent has a lost plugging effect of up to 7 MPa for permeability lost and 1.88 MPa for lost plugging of 2×1 mm fractures.