高活性低密度水泥浆及其强度形成机理研究  

Research on the High-Activity Low-Density Cement Slurry and Its Strength Formation Mechanism

作　　者：王海平 李治 董志明 魏周胜 苏洪生 于骏杰 刘开强[4] WANG Haiping;LI Zhi;DONG Zhiming;WEI Zhousheng;SU Hongsheng;YU Junjie;LIU Kaiqiang(Changqing Cementing Company,CNPC Chuanqing Drilling Engineering Co.,Ltd.,Xi′an,Shaanxi 710018,China;No.2 Gas Production Plant,PetroChina Changqing Oilfield Company,Yulin,Shaanxi 719054,China;Cementing Company of CNPC Xibu Drilling Engineering Co.,Ltd.,Karamay,Xinjiang 83400,China;School of New Energy and Materials,Southwest Petroleum University,Chengdu,Sichuan 610500,China)

机构地区：[1]中国石油川庆钻探工程有限公司长庆固井公司 [2]中国石油长庆油田采气二厂 [3]中国石油西部钻探工程有限公司固井公司 [4]新能源与材料学院·西南石油大学

出　　处：《钻采工艺》2023年第3期147-153,共7页Drilling & Production Technology

基　　金：中国石油川庆钻探工程有限公司研究项目“长裸眼水平井全封固低摩阻固井工作液研究”(编号:CQ2022B-21-1-3);国家自然科学基金“高温高压下过渡态固井水泥浆的失重与传压效率变化机理研究”(编号:52104007)。

摘　　要：为了解决井底高温高压下空心轻质颗粒破碎造成低密度水泥浆流变性恶化摩阻升高、密度上升,固井漏失风险增加的问题,利用高活性实心复合减轻材料和配套激活剂,开发了恒密度、具有二次水化特征的高活性低密度水泥浆体系。文章利用水化热分析仪、X射线衍射仪、热重分析仪和扫描电子显微镜等,研究了高活性低密度水泥浆体系的早期水化反应、水化产物化学结构、微观结构和抗压强度发展规律。结果表明:高温高压下高活性低密度水泥浆具有恒密度、恒流变的特点。在高活性低密度水泥浆中,硅酸盐水泥水化产生的碱性水化产物和水化热可激活复合减轻材料,使该水泥浆早期水化过程中具有二次水化特征,形成“双放热峰”,增加水泥浆的水化热和水化产物含量。高活性低密度水泥浆水化反应消耗Ca(OH)_(2),形成大量钙矾石和C-(A)-S-H,增加该水泥石的水化产物含量、固相体积分数和微观结构致密度。与釉化珍珠岩低密度水泥石相比,水化28 d高活性低密度水泥石的抗压强度提高了16.7%,其耐久性良好。Hollow light particles are prone to crush under high temperature and high pressure at the bottom of the hole,resulting the deterioration of rheological properties of low-density cement slurry,which leads to increase of friction resistance,density and cement loss risk.To deal with the phenomenon,a high-activity low-density cement slurry system(HALDCP)with constant density and secondary hydration characteristics was developed,using high active composite solid materials and supporting activators.Isothermal microcalorimeter,x-ray diffractometer,thermal gravimetric analyzer,scanning electron microscope were applied to analyze the development rule of early hydration,chemical structure of hydration products,microstructure and compressive strength.The results indicated that HALDCP had constant density and rheology.In HALDCP,alkaline hydration products and hydration heat generated by Portland cement activated composite lighting materials,which made the hydration process of the slurry had secondary hydration and formed“Double exothermic peaks”.At the meanwhile,it increased hydration heat and the content of hydration products.Ca(OH)_(2) was depleted by the hydration of HALDCP to form lots of calciumite and C-(A)-S-H,increasing hydration products of the cement,solid volume fraction,microstructural density.In contrast with enameled perlite cement with low density,the compressive strength of HALDCP hydrating for 28 days enhanced 16.7%,and had good durability.

关 键 词：高活性 低密度水泥浆 二次水化 微观结构 力学性能 

分 类 号：TE256[石油与天然气工程—油气井工程]