氧化-还原降解聚丙烯酰胺类压裂液技术与机理研究  

Study on Technology and Mechanism of Oxidation-reduction Degradation of Polyacrylamide Fracturing Fluid

作　　者：陈世军[1] 曹景富 李建山[2] 杨立安 吴江[2] CHEN Shi-jun;CAO Jing-fu;LI Jian-shan;YANG Li-an;WU Jiang(Xi'an Shiyou University,Xi'an Shaanxi 710065,China;PetroChina Changqing Oilfield Branch Oil and Gas Technology Research Institute,Xi'an Shaanxi 710021,China)

机构地区：[1]西安石油大学化学化工学院,陕西西安710065 [2]中国石油长庆油田分公司油气工艺研究院,陕西西安710021

出　　处：《当代化工》2022年第11期2736-2740,2745,共6页Contemporary Chemical Industry

基　　金：国家科学自然基金(项目编号21763030)。

摘　　要：聚合物压裂液降解不彻底,残留的大相对分子质量聚丙烯酰胺进入储层造成储层伤害,极大地影响压裂的储层改造效率。以APS为强氧化剂,研究了不同还原剂对氧化还原破胶的影响。通过红外光谱仪、核磁共振波谱仪和基质辅助激光解吸-飞行时间质谱仪对降解前后的聚丙烯酰胺进行了表征分析,测定了氧化还原的破胶降解机理。实验结果表明:FeCl_(2)作为引发剂和S_(2)O_(8)^(2-)进行复配降解效果最好,降解后聚丙烯酰胺压裂液黏度由27.8mPa·s下降到5.03mPa·s,聚丙烯酰胺相对分子质量由2000万下降到250万左右。If the polymer fracturing fluid is not degraded completely, the residual high molecular weight polyacrylamide enters the reservoir to cause reservoir damage, which greatly affects the efficiency of fracturing reservoir reconstruction. In this paper, APS was used as strong oxidant to study the effect of different reductants on redox gel breaking. The polyacrylamide before and after degradation was characterized and analyzed by infrared spectrometer, nuclear magnetic resonance spectrometer and matrix assisted laser desorption time-of-flight mass spectrometer. It was determined that the gel breaking mechanism of redox was that free radicals ·OH could be generated through redox reaction, and the free radicals could cause the molecular chain of polyacrylamide to break, thus leading to the degradation of polyacrylamide. The experimental results showed that FeCl_(2)as initiator and S_(2)O_(8)^(2-)had the best degradation effect. After degradation, the viscosity of EM30S decreased from 27.8 m Pa·s to 5.03 m Pa·s, and the molecular weight of polyacrylamide decreased from 20 million to about 2.5 million.

关 键 词：压裂液 聚丙烯酰胺 氧化还原 降解 

分 类 号：TQ031[化学工程]