新型纳米复合聚合物压裂液体系研究及应用

Preparation of Novel Nanocomposite Polymer PADD-1 and Its Application in Fracturing Fluid

常规滑溜水和聚合物压裂液在高温高盐储层压裂施工过程中存在黏度低、剪切稳定性不足和携砂能力差等缺点,使其在非常规储层压裂中造缝能力不足,影响压裂后的产能。为此,以丙烯酰胺(AM)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)和功能单体DRS-1为原料,利用水溶液聚合法合成了聚合物PADD,再通过添加纳米二氧化硅制备出新型纳米复合聚合物PADD-1,优选协同作用良好的黏土稳定剂和助排剂,形成新型纳米复合聚合物压裂液体系。实验结果表明,新型纳米复合聚合物压裂液具有良好的耐温抗剪切性能,在150℃和170 s-1的条件下剪切120 min后黏度仍能保持在50 mPa·s以上;该压裂液体系的携砂能力较强,并且破胶后的残渣含量较低。该压裂液体系成功应用于某致密油藏,增产效果明显。

Conventional fracturing fluid has defects such as low viscosity,insufficient shear stability and poor proppant carrying capacity in the process of fracturing in high-temperature and high-salt reservoirs,which makes it insufficient width generation capacity in unconventional reservoirs,which affects the production capacity after fracturing.To this end,acrylamide(AM),methacryloyloxyethyl trimethyl ammonium chloride(DMC)and functional monomer DRS-1 were used as raw materials to synthesize polymer PADD by aqueous solution polymerization.A novel nanocomposite polymer PADD-1 was prepared by adding nano-silica and polymer PADD-1,and a new nanocomposite polymer PADD-1 fracturing fluid system was formed by selecting clay stabilizers and drainage aids with good synergy.The experimental results show that under the synergistic effect of various additives,the fracturing fluid has good shear resistance at 150℃,strong proppant carrying ability,reduces the amount of polymer to a certain extent,and has low residue content after breaking the glue.The fracturing fluid system was successfully applied to a tight oilfield,and the production increase effect was obvious.