一种超低密度水泥浆抗高温降失水稳定剂QX-2的制备 与性能评价

Preparation and Performance Evaluation of Anti-high-temperature Water Loss Stabilizer QX-2 Used in Ultra-low-density Cement Slurry

为克服高温条件下超低密度水泥浆减轻剂游离上浮、聚集等问题,通过水溶液聚合法利用单体N,N-二甲基丙烯酰胺(DMAM)、二乙烯苯(DVB)、对苯乙烯磺酸钠(SSS)和N-乙烯基吡咯烷酮(NVP)制备了抗高温降失水稳定剂QX-2,通过傅立叶变换红外光谱(FTIR)对其分子结构进行了表征,并考察了其对超低密度水泥浆体系的沉降稳定性能、降滤失性能、流变性能、稠化性能、水泥石抗压强度、抗盐性能的影响。结果表明,抗高温降失水稳定剂QX-2在温度高达150℃的超低密度水泥浆体系中仍具有较好的沉降稳定性能和降滤失性能,其上、下层密度差在0.03 g·cm^(-3)以内;QX-2能保证超低密度水泥浆的稠度系数稳定,具有良好的流变性能;QX-2能使水泥石抗压强度增强,有利于提高超低密度水泥浆体系的固井质量;QX-2具有优良的抗盐性能,可拓宽超低密度水泥浆体系的应用环境。

In order to solve free floating and aggregation of lighting agent of ultra-low-density cement slurry under high-temperature conditions,we prepared an anti-high-temperature water loss stabilizer QX-2 by aqueous solution polymerization using monomer N,N-dimethylacrylamide(DMAM),divinylbenzene(DVB),sodium p-styrene sulfonate(SSS)and N-vinylpyrrolidone(NVP).Moreover,we characterized the molecular structure of QX-2 by FTIR.Furthermore,we investigated the effects of QX-2 on the settlement stability,filtration-reducing performance,rheological performance,thickening performance,compressive strength of cement stone,and salt resistance performance of ultra-low-density cement slurry system.The results show that the prepared QX-2 still has good settlement stability and filtration-reducing performance in ultra-low-density cement slurry system at temperature higher than 150℃,and the density difference between the upper and lower parts of the cement slurry is low than 0.03 g·cm^(-3).The prepared QX-2 can ensure the stability of the consistency coefficient of the ultra-low-density cement slurry and has good rheological performance.The prepared QX-2 can enhance the compressive strength of cement stone,which is beneficial for improving the cementing quality of the ultra-low-density cement slurry system.The prepared QX-2 has excellent salt resistance performance,which can expand the application field of ultra-low-density cement slurry system.