等离子体改性氧化镁晶须增强铝酸盐水泥高温力学性能  

Enhancing High Temperature Mechanical Performance of Aluminate Cement with Plasma-Modified MgO Whisker

作　　者：幸雪松 程小伟[2] 李杲 倪修成 王晋瑶 武治强 XING Xuesong;CHENG Xiaowei;LI Gao;NI Xiucheng;WANG Jinyao;WU Zhiqiang(CNOOC Research Institute Co.,Ltd.,Beijing 100028;Southwest Petroleum University,Chengdu Sichuan,610500;Cost Center Of Engineering Project,Petrochina Southwest Oil&Gas Field Company,Chengdu Sichuan,610051)

机构地区：[1]中海油研究总院有限责任公司,北京100028 [2]西南石油大学新能源与材料学院,成都610500 [3]中国石油西南油气田分公司工程项目造价中心,成都610051

出　　处：《钻井液与完井液》2021年第3期341-345,共5页Drilling Fluid & Completion Fluid

基　　金：中海石油(中国)有限公司科技项目“超高温高压开发井钻完井风险评估与对策研究”(2021-YXKY-001)、中海油研究总院研究课题“超高温高压固井工艺措施研究及水泥浆体系优选”(2019PFS-11-005)。

摘　　要：水泥石的高温脆性和低拉应力限制了其在稠油热采井中的应用。笔者选用等离子体改性氧化镁晶须来增强铝酸盐水泥的高温力学性能。结果表明,等离子体改性氧化镁晶须的表面微观结构更为粗糙,可更好地与水泥石产生胶结,进而提高力学性能。在500℃下养护7 d后,掺入2%等离子体改性氧化镁晶须的水泥石相比于掺入2%未改性氧化镁晶须的水泥石,其高温力学性能明显提升,抗压、抗拉强度分别增长了24.5%和14.1%;同时掺入2%等离子体改性氧化镁晶须的水泥石的应力应变性能也更为优异,具有更高的应力峰值与更低的弹性模量。最后通过SEM和EDS等表征方法,对掺入晶须的水泥石微观形貌进行分析,认为晶须作用于水泥基体时,分别通过裂纹偏转、晶须断裂和桥联等途径达到增强水泥石力学性能的效果。High brittleness and low tensile strength at elevated temperatures of set cement limits its use in thermal production of heavy oils.In laboratory study,a plasma-modified magnesium oxide(MgO)whisker was used to enhance the high temperature mechanical properties of aluminate cement.It was found through the study that the surface microstructure of the plasma-modified MgO whiskers is rougher than that of the original MgO whiskers,and are thus better bonded with cement to form set cement with improved mechanical properties.After aging at high temperature for 7 days,the set cement containing 2%plasma-modified MgO whiskers has more significant improvement in mechanical performance than the set cement containing 2%MgO whiskers without plasma-modification;the compressive strength and tensile strength of the set cement containing 2%plasma-modified MgO whiskers are 24.5%and 14.1%higher than those of the set cement containing 2%MgO whiskers without plasma-modification,respectively.It was also found that the set cement containing 2%plasma-modified MgO whiskers has better stress-strain performance;it has higher peak stresses and lower elastic modulus.Characterization of the micro morphology of the set cement with whickers with SEM and EDS indicated that the whiskers act on the matrix of cement through crack deflection,whisker fracture and bridging,thereby enhancing the mechanical performance of set cement.

关 键 词：稠油 固井 铝酸盐水泥 氧化镁晶须 等离子体改性 力学性能 

分 类 号：TE254.6[石油与天然气工程—油气井工程]