二氧化碳多轮次吞吐温压效应及反复应力损伤理论指导减少套管损伤数量  

Thermal-Pressure effects of multi-cycle carbon dioxide huff&puff and repeated stress damage:A theoretical approach to reducing casing deformation frequency

作　　者：宋显民[1] 耿海涛[1] 肖国华[1] 何歆如 殷彩霞[1] 郑智峰 SONG Xianmin;GENG Haitao;XIAO Guohua;HE Xinru;YIN Caixia;ZHENG Zhifeng(Oil And Gas Gathering and Transportation Company of Jidong Oilfield Branch of CNPC,Tangshan,Hebei,063004,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu,Sichuan,610059,China)

机构地区：[1]中国石油天然气股份有限公司冀东油田分公司,河北唐山 [2]油气藏地质及开发工程全国重点实验室,四川成都

出　　处：《石油钻采工艺》2024年第4期429-442,共14页Oil Drilling & Production Technology

基　　金：国家重点研发计划“二氧化碳地质封存协同枯竭页岩储层增渗开采技术”(项目编号:2023YFE0110900)。

摘　　要：(目的意义)冀东油田现有套管损伤机理及其影响因素的研究存在较大局限,导致套管损伤评价无法量化。(方法过程)研究基于高温高压多场耦合岩石力学测试系统开展了12组室内单轴和三轴试验,结合ANSYS软件建立了套管-水泥环-地层耦合的三维地质模型,分析了出砂程度、吞吐轮次、射孔孔密、固井质量、生产时间5种因素对岩石及套管应力损伤的影响,并与冀东油田现场数据对比相关性达到98.8%,验证了损伤影响因素的可靠性。(结果现象)现场试验验证,二氧化碳在高温高压条件下对岩石强度的影响是套管损伤的主要因素,建议提高防砂精度,吞吐轮次不超过16轮、孔密不超过12孔/m,套管强度提高1~2个钢级,提高固井质量以降低套管损伤概率。通过采取针对性防治措施,研究区块套管损伤程度降低约30%,裂缝扩展速度降低25%,井口压力波动下降15%。(结论建议)研究结果为二氧化碳多轮次吞吐施工参数优化设计提供新的技术思路。The research on the current casing deformation mechanism and its influencing factors in Jidong Oil Field has a large limitation,which makes the casing deformation evaluation unable to be quantified.In order to reduce the number of casing deformation,12 groups of laboratory uniaxial and triaxial tests are carried out based on the high temperature and high pressure multifield coupling rock mechanics test system.Combined with ANSYS software,a three-dimensional geological model of casing-cement sheath-formation coupling is established.The influence of 5 factors on the rock and casing stress damage is analyzed,including sand production degree,cycle of huff and puff,perforation density,cementing quality and production time.The correlation with field data in Jidong Oil Field reaches 98.8%,and the reliability of the damage influencing factors is verified.The field test verification shows that the influence of carbon dioxide on rock strength under high temperature and high pressure is the main factor of casing deformation.It is suggested to improve the sand control accuracy,the number of cycles of stimulation shall not exceed 16,the hole density shall not exceed 12 holes/m,the casing strength shall be increased by 1~2 steel grades,and the cementing quality shall be improved to reduce the casing deformation probability.Through taking targeted prevention and control measures,the casing deformation degree of the research block is reduced by about 30%,the crack propagation speed is reduced by 25%,and the wellhead pressure fluctuation is reduced by 15%.The research results provide a new technical idea for the optimal design of construction parameters of carbon dioxide multi-cycle huff and puff.

关 键 词：二氧化碳吞吐 油气资源 非常规油气 井筒完整性 工程技术 室内测试 岩石强度 

分 类 号：TE931.2[石油与天然气工程—石油机械设备]