常见无机盐对油井水泥石抗压强度的影响机理  

Mechanism Research on How Inorganic Salt Affect on Cement Stone Compressive Strength

作　　者：艾丽[1] 李早元[1] 谢飞燕[1,2] 郭小阳[1] 

机构地区：[1]油气藏地质及开发工程国家重点实验室·西南石油大学,成都 [2]天津中油渤星工程科技有限公司,天津

出　　处：《钻井液与完井液》2012年第4期63-65,92,共3页Drilling Fluid & Completion Fluid

基　　金：中国石油天然气集团公司科研计划科技现场试验项目"土库曼斯坦复杂盐下气田快速高效勘探开发技术"(2008-15)

摘　　要：在井下盐膏层中水泥石受各种无机盐侵蚀,易出现长期强度发展缓慢、结构破坏现象,研究无机盐对水泥石抗压强度的影响机理,对减缓无机盐侵蚀水泥环,提高油气井使用寿命具有重要意义。通过考察90℃时含氯化钠水泥石受碱金属氯盐、硫酸盐饱和溶液侵蚀强度衰退的程度,研究了水泥石抗压强度衰退规律和影响原因。实验结果表明,含5%氯化钠水泥石能抵抗硫酸盐、氯盐的侵蚀,水泥石强度大;内部盐增加到10%,会导致水泥石内部孔隙增多,受侵蚀深入,破坏结构;氯盐、硫酸盐侵蚀水泥石时生成膨胀性物质,堵塞水泥石内部空隙,促进强度增长,膨胀性物质生成量超过孔隙承受量时破坏孔隙,膨胀破坏达到平衡时强度趋于稳定。Cement stone suffers erosion from various kinds of inorganic salt in gypsum bed formation, easy to slow downthe long-term strength development. The mechanism research on how inorganic salt affect on cement stone compressivestrength is very important to increase the service life of oil and gas well. In this paper, the strength regression extent ofcement stone containing sodium chloride in the alkali metal chloride and sulfate saturated solution at 90 ? is studied, andthe law and affecting factors of cement stone strength regression is discussed. The experimental results slow that whencement stone containing 5% sodium chloride, it can resist to erosion from chloride and sulfate with great strength, when theinternal sodium chloride up to 10%, it leads more inner pores and deeper erosion. Furthermore, some swelling materials aregenerated by contamination of chloride and sulfate, which can block the inner pores, promote strength growth, however,when the amount of swelling material exceeds the limit, the pores will be destroyed, and the cement stone strength tends tobe stable when the swelling capacity and pores destruction rate achieve balance.

关 键 词：固井 盐膏层 水泥石 无机盐 强度衰退 

分 类 号：TE256.9[石油与天然气工程—油气井工程]