固井用聚合物高温悬浮剂的合成及性能研究

Study on Synthesis and Performance of Polymer High Temperature Suspending Agent for Cementing

针对目前超深超高温井固井过程中水泥浆悬浮稳定性差、综合性能不足的问题,基于水泥浆高温沉降失稳机理分析,用2-丙烯酰胺基-甲基丙磺酸(AMPS)、丙烯酰胺(AM)、N-乙烯基吡咯烷酮(NVP)和二甲基二烯丙基氯化铵(DMDAAC)合成了一种四元共聚物悬浮剂P(AADN),其结构和性能经红外光谱、热重分析及环境扫描电镜等表征。结果表明:悬浮剂水溶液呈现均匀的交联网架结构且热稳定性良好;在200℃下,P(AADN)加量为0.5%时,水泥石上下密度差小于0.02 g/cm^(3);同时,水泥浆体系流变性、稠化性能等均良好,可满足现场施工要求。

Aiming at the problems of poor suspension stability and insufficient comprehensive performance of cement slurry during the cementing process of ultra-deep and ultra-high temperature wells,based on the analysis of the mechanism of high temperature settlement instability of cement slurry,a quaternary copolymer suspending agent[P(AADN)]was synthesized with AMPS,AM,DMDAAC and NVP.The structure and property of P(AADN)were characterized by infrared spectroscopy,thermogravimetric analysis and environmental scanning electron microscopy,etc.The results showed that the molecular structure of the suspending agent conformed to the expected design,and the aqueous solution of the suspending agent exhibited a uniform cross-network structure and good thermal stability.Performance evaluation results showed that when the addition of suspending agent P(AADN)was 0.5%at 200℃,the upper and lower density difference of cement can be controlled to be less than 0.02 g/cm^(3);at the same time,the rheology and thickening performance of the cement slurry system both were good,which meet the requirements of the site construction requirements.