液体封窜剂的制备与性能评价

Preparation and Performance Evaluation of Liquid Channeling Sealing Agent

王少锋 何 龙 董瑞强 黄雪莉

WANG Shaofeng HE long DONG Ruiqiang HUANG Xueli

针对塔河油田固井水泥环的窜漏治理问题，用甲醛与苯酚合成了酚醛预聚体，将其与 2-丙烯酰胺基-2-甲基丙磺酸和丙烯酰胺二元共聚物（AM-AMPS）混合制得液体封窜剂。通过红外光谱仪和质谱仪对酚醛预聚体的结构进行了表征，研究了 AM-AMPS与酚醛预聚体加量、温度对封窜剂固化的影响，评价了封窜剂的稳定性。结果表明，在甲醛与苯酚摩尔比为 2.8∶1、体系 pH值为 8～ 10时，合成的酚醛预聚体为 2～ 3聚合度的甲阶酚醛树脂，其中羟甲基甲醛含量为 36.1%、游离甲醛含量为 0.03%。适量的聚合物 AM-AMPS可增加酚醛预聚体与套管壁的胶结能力，提高封窜剂的突破压力梯度。封窜剂（0.5% AM-AMPS+40%酚醛预聚体）在 140℃下以固化反应为主体反应，固化后的突破压力梯度为 150.6 MPa/m，固化时间为 37 min。封窜剂固化后的强度随酚醛预聚体加量的增大而增加，随温度的变化较小。温度是影响封窜剂固化时间的主要因素。封窜剂在高温（90～ 140℃）、高盐（100～ 240 g/L）下的稳定性较好，可用于塔河油田封窜堵漏。图 8参 15

In view of the leakage control problem of cement sheath in Tahe oilfield，the liquid channeling sealing agent was prepared by mixing 2-acrylamide-2-methylpropane sulfonic acid and acrylamide coploymer （AM-AMPS） with phenolic prepolymer which was synthesized from formaldehyde and phenol. The structure of phenolic prepolymer was characterized by infrared spectrometer and mass spectrometry. The effects of the concentrations of polymer AM-AMPS and phenolic prepolymer，and temperature on the curing of channeling sealing agent were studied，and the stability of channeling sealing agent was evaluated. The results showed that the when the molar ratio of formaldehyde to phenol was 2.8∶1 and the pH value of the system was 8—10，the synthesized phenolic prepolymer was a resole phenolic with 2—3 degree of polymerization. The mass fraction of hydroxymethyl formaldehyde and free formaldehyde was 36.1% and 0.03% respectively. Appropriate amount of AM-AMPS could increase the cementation ability between phenolic prepolymer and pipe wall，and improve the breakthrough pressure gradient of channeling sealing agent. The main reaction of channeling sealing agent（0.5% AM-AMPS+40% phenolic prepolymer）was curing reaction at 140℃ . The breakthough pressure gradient after curing was 150.6 MPa/m and the cruing time was 37 min. The strength of channeling sealing agent after curing increased with increasing amount of phenolic prepolymer，and was less impacted by temperature. Temperature was the main factor affecting the curing time of channeling sealing agent. The channeling sealing agent had good stability under high temperature（90—140℃）and high salinity（100—240 g/L），which could be used to seal channel and plug leakage in Tahe oilfield.