出砂气藏井底防砂筛管冲蚀动态模拟试验及冲蚀损坏工况评价方法  

Dynamic simulation experiments of erosion and erosion damage assessment method of bottom-hole sand control screen in sand-producing gas reservoirs

作　　者：董长银[1,2] 李经纬 周博 黄亮[3] 刘亚宾 李强[4] 黄有艺 DONG Changyin;LI Jingwei;ZHOU Bo;HUANG Liang;LIU Yabin;LI Qiang;HUANG Youyi(School of Petroleum Engineering,China University of Petroleum(East China),Qingdao 266580,Shandong,China;Key Laboratory of Unconventional Oil and Gas Development,Ministry of Education,Qingdao 266580,Shandong,China;Zhanjiang Branch,CNOOC(China)Co.,Ltd.,Zhanjiang 524057,Guangdong,China;Oilfield Production Department of COSL Co.,Ltd.,Tianjin 300450,China)

机构地区：[1]中国石油大学(华东)石油工程学院,山东青岛266580 [2]非常规油气开发教育部重点实验室,山东青岛266580 [3]中海石油(中国)有限公司湛江分公司,广东湛江524057 [4]中海油田服务股份有限公司油田生产事业部,天津300450

出　　处：《安全与环境学报》2023年第6期1859-1867,共9页Journal of Safety and Environment

基　　金：国家自然科学基金项目(52074331)。

摘　　要：为了对出砂气藏井底筛管的冲蚀现象进行定量评价,针对常用的多层滤网复合筛管,利用创新研制的水平井筒封闭空间筛管冲蚀模拟试验系统,使用气体携砂开展系列筛管冲蚀损坏模拟试验,系统分析和揭示了冲蚀损坏机理。拟合提出了针对筛管本身的抗冲蚀指数评价指标,用于同类筛管产品评价对比;构建了筛管冲蚀损坏工况评价方法,用于实际天然气井井底冲蚀损坏判定。结果表明,气体携砂冲蚀多层滤网复合筛管的损坏机理为正面啃噬和侧面切削,揭示了井底有限封闭空间下筛管外环空砂埋堆积对筛管冲蚀具有保护作用。在冲蚀试验过程中也发现,滤网的抗冲蚀能力远低于外保护罩,其冲蚀损毁时间约是保护罩的1/8。根据试验结果拟合得到冲蚀速率与冲蚀特征函数为线性关系,拟合得到抗冲蚀指数则与冲蚀条件无关,仅表征筛管本身的机械抗冲蚀能力。针对实际井底工况提出实际气井局部高速入流系数描述井底入流非均质性特征,考虑井筒封闭空间中的冲蚀与砂埋动态关系,提出了筛管冲蚀损坏系数评价方法,即井底是否发生筛管损坏取决于井底实际冲蚀速度和筛管外环空砂埋的相对速度。对于南海某气藏,当局部高速入流系数超过3500时,井底冲蚀可能性较大。所提出的冲蚀工况评价方法将室内试验规律和井底工况结合起来,考虑了筛管本身的抗冲蚀性能和井底实际环境条件,为出砂气藏防砂完井设计及冲蚀完整性评价提供了有效方法。Aiming at the commonly used multi-layer metal mesh screen,the closed space experiment system of erosion simulation for the screen was developed,and a series of screen erosion damage simulation experiments were carried out by gas-carrying sand.The erosion damage mechanism was systematically analyzed and revealed.The anti-erosion evaluation index for the screen itself was proposed for the evaluation and comparison of similar screen products.The assessment method of screen erosion damage was constructed to determine the erosion risk of actual natural gas wells.The results show that the damage mechanism of gas sand-carrying erosion of multi-layer metal mesh screen is positive gnawing and side cutting,which reveals that the sand-buried accumulation at the annulus has a protective effect on the screen erosion under the limited closed space at the well bottom.It is also found that the erosion resistance of the metal mesh is much lower than that of the outer protective shroud,and the erosion time is about 1/8 of that of the protective shroud.According to the experimental results,the erosion rate is linear with the erosion characteristic function,and the antierosion index obtained by fitting is independent of the erosion conditions,which only characterizes the mechanical erosion resistance of the screen itself.Given the actual bottom hole condition,the local high-speed inflow index of the actual gas well was proposed to describe the heterogeneity characteristics of bottom hole inflow.Considering the dynamic relationship between erosion and sand burial in wellbore closed space,the evaluation index of screen erosion was proposed,that is,whether erosion damage in the bottom hole depends on the actual bottom hole erosion speed and the relative speed of sand burial.For a gas reservoir in the South China Sea,the bottom hole erosion risk is high when the local high-speed inflow index exceeds 3500.

关 键 词：安全工程 防砂筛管 筛管冲蚀 冲蚀性能 工况评价 模拟试验 

分 类 号：X937[环境科学与工程—安全科学]