多用途低温低密水泥浆体系室内研究及应用

Indoor research and application of multi-purpose low-temperature and low-density cement slurry system

多用途低温低密水泥浆体系,以G级油井水泥为基质,以人造玻璃微珠及火山灰活性胶凝材料为减轻材料,并辅其他功能性添加剂构建而成。体系以固相悬浮为基础模型,以紧密堆积技术为基本理论。通过优化颗粒级配提高单位体积水泥浆中的固相体积分数。减轻材料的使用进一步减少了固相颗粒间的游离水,降低水灰比,增强水泥石的致密性,降低渗透率,促进水泥石早期强度发展。现场应用结果表明,在不改变水泥浆体系材料种类的基础上,水泥浆配浆密度可实现1.4 g/cm^(3)与1.5 g/cm^(3)转换,同时可实现淡水配浆及海水配浆双液体作业;水泥浆适用温度范围为30~80℃;具有良好的浆体流动性,API失水可控,自由水为零,早期强度高,稠化时间可调。

A multi-purpose low-temperature and low-density cement slurry system was constructed by G grade oil well cement as the matrix,and artificial glass microspheres and volcanic ash active cementitious materials as low density materials,and other functional additives.The system was based on solid-phase suspension as the basic model,and dense packing technology as the basic theory.The volume fraction of solid-phase in cement slurry was increased by optimizing particle grade.The using of low density materials could reduce the free water between solid particles,and lower the water cement ratio,and increase the compactness and reduce permeability of the cement stone,and promote the early strength development of cement stone.The on-site application results showed that the density of cement slurry can be converted from 1.4 g/cm^(3) to 1.5 g/cm^(3) without changing the material type of the cement slurry system,and it could achieve dual liquid operation for both freshwater based and seawater based cement slurry system.This cement slurry system had a suitable temperature range of 30~80℃,and good slurry fluidity,and controllable API fluid loss,and zero free water,and high early strength,and adjustable thickening time.