一种适于盐膏层大井眼固井的抗盐高强水泥浆——以巴西Libra油田为例  

A Kind of Salt-resistant and High-strength Cement Slurry Suitable for Large Hole Cementing in Salt Bed——Taking the Libra Oilfield in Brazil as an Example

作　　者：黄伟[1] 王晓亮[2,3] 杨晓榕 胡顺 刘郢 张敏 张易航 Huang Wei;Wang Xiaoliang;Yang Xiaorong;Hu Shun;Liu Ying;Zhang Min;Zhang Yihang(Tanggu Operation Company,Oilfield Chemistry Division of CNOOC Oilfield Services Co.Ltd.,Tianjin 300459;Hubei Cooperative Innovation Center of Unconventional Oil and Gas,Yangtze University,Wuhan 430100,Hubei;Jingzhou Jiahua Technology Co.Ltd.,Jingzhou 434000,Hubei;School of Petroleum Engineering,Yangtze University,Wuhan 430100,Hubei)

机构地区：[1]中海油田服务股份有限公司油田化学事业部塘沽作业公司,天津300459 [2]非常规油气湖北省协同创新中心(长江大学),湖北武汉430100 [3]荆州嘉华科技有限公司,湖北荆州434000 [4]长江大学石油工程学院,湖北武汉430100

出　　处：《长江大学学报（自然科学版）》2020年第5期42-48,I0003,共8页Journal of Yangtze University(Natural Science Edition)

基　　金：国家科技重大专项“海外复杂地层固井及修井液技术”(2017ZX05032004-004)。

摘　　要：针对大井眼盐膏层高压封固段长、环空间隙大、泥浆密度窗口较窄、盐膏层蠕动作用造成胶结质量差等特点,结合前期固井作业问题开展试验研究,确定密度为2.4g/cm^3抗盐高强水泥浆的盐质量分数为15%~20%;根据加重剂的特点及紧密堆积模型,进行3级粒径加重剂紧密堆积设计,确定该密度下加重剂组成为赤铁矿粉和锰矿粉MC200G复配(质量比为4∶1)的加重剂MICD,该加重剂可实现球形加重剂的加重效果,但价格只有球形加重剂的一半;引入了抗盐AMPS类聚合物降失水剂,形成的抗盐高强水泥浆体系具有浆体稳定性能及流变性能好、稠化时间可控、高温下早期抗压强度高等特点,2.3g/cm^3和2.4g/cm^3抗盐高强水泥浆较常规水泥浆的抗冲击功分别提高了23.3%、31.8%,水泥石弹性模量分别降低了20.4%、26.6%,说明该水泥石具有良好的弹性和高抗冲击性,可避免现场作业时水泥环受到应力作用造成的破损,能够确保水泥环的完整性。According to the characteristics of large hole in the salt bed,such as long high-isolation-section,large annular space,narrow mud density window,poor cementation quality caused by the peristalsis in salt bed,etc.,based on the problems of early cementing operation,the experimental study was carried out and the salt mass fraction of the salt-resistant and high-strength cement slurry with the density of 2.4g/cm^3 was determined to be 15%~20%.According to the characteristics of the weighting agent and the close packing model,the close packing design of grade-3 particle size weighting agent was carried out,and the composition of the weighting agent at the density was determined to be MICD of the weighting agent mixed with hematite powder and MC200G(The mass ratio is 4∶1).The weighting agent can realize the effect of spherical weighting agent,but its price is only half of that of the spherical weighting agent.The salt-resistant AMPS polymer fluid loss additive was introduced to form the salt-resistant and high-strength cement slurry system,which has the characteristics of good slurry stability,good rheological property,controllable thickening time,high early compressive strength at high temperature,etc.Compared with the conventional cement slurry,the impact strength of 2.3g/cm^3 and 2.4g/cm^3 salt-resistant and high-strength cement slurry was respectively increased by 23.3%and 31.8%,and their elastic modulus of cement paste was reduced by 20.4%and 26.6%respectively.It shows that the cement paste has good elasticity and high impact resistance,which can avoid the damage of cement sheath caused by stress during the field operation and ensure the integrity of cement sheath.

关 键 词：盐膏层 大井眼固井 抗盐高强水泥浆 性能评价 巴西Libra油田 

分 类 号：TE256.1[石油与天然气工程—油气井工程]