固井二界面泥饼的固化反应

MudCakeSolidificationReactionatCement-FormationInterface

熊跃 王剑波 李忠献 杨易骏 何吉标 顾军 郝海洋

XIONG Yue WANG Jianbo LI Zongxian YANG Yijun HE Jibiao GU Jun HAO Haiyang

对比考察了现有技术和泥饼固化（MCS）技术的固井二界面胶结强度，通过环境扫描电子显微镜（ESEM）考察了固井二界面泥饼的微观形貌，并通过差示扫描量热仪（DSC ）测试对固化反应动力学进行了动态分析。实验结果表明，95℃水浴养护3 d、7 d 和15d 条件下，MCS技术的固井二界面胶结强度分别较现有技术的平均提高 了439.33% 、471.37% 和194.11 % 。ESEM 分析表明，MCS技术使固井二界面胶凝固化为一个胶结致密整体，泥饼固化效果显著。在泥饼固化剂作用下，泥饼发生了溶蚀- 胶凝固化反应，实现了固井二界面整体固化胶结。Kissinger 法和Ozawa 法求取的固化反应表观活化能分别为101.33kJ/mol 和106.55kJ/mol ；固化反应级数为0.95，泥饼固化反应是由多个简单反应复合而成的复杂反应。图6 表2 参13

Based on existing technology and mud cake solidification （MCS）technology, the bonding strength at cement-formation interface （BSCFI）were evaluated, the microstructures of the mud cake at cement-formation interface was observed by environmental scanning electron microscope（ESEM）, and the kinetics of the solidification reactions was analyzed by differential scanning calorimeter （DSC ）. The experimental results showed that after maintaining at the temperature of 95℃for 3 days,7 days and 15days in MCS technology the BSCFI was improved by 439.33%,471.37% and 194.11 %, respectively, compared with that in existing technology. ESEM observation showed that the mud cake combined solidly with the formation and cement sheath. It could be deduced that the dissolution-gel solidification reaction in the mud cake occurred under the action of the mud cake solidifier, as a result, the integrated solidification and cementation of cement-formation interface was achieved. The apparent activation energy of the samples in MCS technology was calculated by Kissinger method and Ozawa method, being of 16.01kJ ·mol-1 and 21.01kJ mol-1,respectively. The reaction order was calculated to be 0.95, which indicated the solidification reactions were consisted of several elementary reactions.