超深水浅层钻井液体系研究与应用  

Research and application of ultra-deepwater shallow drilling fluid system

作　　者：刘喜亮[1] 王雪松[1] 魏久勇 刘雄 周志奇 LIU Xiliang;WANG Xuesong;WEI Jiuyong;LIU Xiong;ZHOU Zhiqi(Hainan Operation Company,Oilfield Chemical Division,COSL,Haikou Hainan 570100,China)

机构地区：[1]中海油田服务股份有限公司油田化学事业部海南作业公司,海南海口570100

出　　处：《石油化工应用》2024年第12期38-42,共5页Petrochemical Industry Application

摘　　要：南海超深水浅层井泥面温度低,目的层埋藏深度浅,岩性疏松,面临低温钻井液流变性调控难、井壁稳定性差、压力窗口窄、井下漏失风险高、浅层天然气水合物易形成等一系列难题,钻井安全风险高。因此,室内以现有的深水HEM钻井液体系为基础,优选了密度减轻剂E、增黏剂XC、抑制剂UHIB以及水合物抑制剂MEG等处理剂,构建了一套适合超深水勘探的HEM钻井液体系。实验评价结果表明,体系具有较低的黏度和较高的切力,在3~25℃流变性能稳定,具有良好的携岩能力和降滤失效果。封堵承压达7 MPa,抗钻屑污染达10%,抗NaCl污染达15%,具有良好的承压、抗钻屑、抗盐污染能力。该体系在现场多口井成功应用,钻井液流变性能稳定,起下钻顺利,井径控制良好,未发生井下漏失、天然气水合物堵塞等井下复杂情况,为超深水浅层井的钻井作业提供了典型的借鉴样本。The ultra-deepwater shallow wells in the South China Sea have low mud surface temperature,shallow burial depth and loose lithology,facing a series of difficult problems such as low temperature drilling fluid rheological control,poor wellbore stability,narrow pressure window,high risk of downhole leakage,shallow gas hydrate formation,etc.,and the drilling safety risk is high.Therefore,based on the existing deepwater HEM drilling fluid system,the laboratory optimized treatment agents such as density reducer E,tackifier XC,inhibitor UHIB,and hydrate inhibitor MEG,and constructed a set of HEM drilling fluid system suitable for ultra-deepwater exploration.Experimental evaluation results show that this system has lower viscosity and higher shear force,stable rheological properties between 3~25℃,and has good rock-carrying capacity and filter loss reduction effect.The sealing pressure is up to 7 MPa,the resistance to drilling cuttings pollution is up to 10%,and the resistance to NaCl pollution is up to 15%.It has good pressure bearing,drilling cuttings resistance,and salt pollution resistance.This system has been successfully applied in many wells on site.The rheological properties of the drilling fluid are stable,tripping is smooth,the well diameter is well controlled,and complex underground conditions such as downhole losses and natural gas hydrate blockage have not occurred,providing a typical reference sample for the drilling operation of ultra-deepwater and shallow wells.

关 键 词：超深水 低温流变性 密度减轻剂 井壁稳定 天然气水合物 

分 类 号：TE254.1[石油与天然气工程—油气井工程]