摘要
针对龙马溪组地层页岩微纳米多尺度孔缝发育导致的井壁失稳难题,文章通过对龙马溪组代表性泥页岩的矿物组成、微观结构特征和页岩理化特征等测试分析,明确了龙马溪组页岩井壁失稳的潜在机理,并针对性提出了“多级封堵、强化抑制”的技术对策,优选出了纳米封堵剂PJ-WBA、PJ-JCD和聚胺抑制剂,构建出一套适用于开发页岩的致密封堵防塌钻井液体系PJ-1,并在现场成功应用。室内研究表明,该体系PJ-1可对孔径与地层孔缝尺寸相近的滤膜均能实现较好的封堵,PPA滤失量由12 mL降低至6.4 mL,表现出较好的封堵性能,使页岩渗透性滤失量降低率达98%以上,并且该体系具有良好的抗污染性。现场应用表明,所研制的PJ-1钻井液有效解决了井壁失稳的情况,井径扩大率仅为3.27%,进一步降低了钻井周期和成本,为该区块页岩气高效钻探开发提供了技术保障。
Addressing the wellbore instability challenge caused by the development of micro-and nano-scale pores and fractures in the Longmaxi Formation shale,this article clarifies the potential mechanisms behind wellbore instability in Longmaxi Formation shale through testing and analysis of the mineral composition,microstructural characteristics,and physicochemical properties of representative Longmaxi Formation shale.It specifically proposes a technical countermeasure of"multi-level sealing and enhanced inhibition",selects nano-sealing agents PJ-WBA and PJ-JCD,as well as a polyamine inhibitor,and constructs a set of tight sealing and anti-collapse drilling fluid system PJ-1 suitable for shale development,which has been successfully applied on site.Laboratory studies show that this system PJ-1 can achieve good sealing performance for filter membranes with pore sizes similar to those of the formation pores and fractures,reducing the PPA filtration loss from 12 mL to 6.4 mL,demonstrating a good sealing performance that reduces the shale permeability filtration loss by over 98%.Additionally,this system exhibits good anti-pollution properties.Field applications indicate that the developed PJ 1 drilling fluid effectively solves the problem of wellbore instability,with a well diameter expansion rate of only 3.27%,further reducing the drilling cycle and cost,providing technical support for efficient drilling and development of shale gas in this block.
作者
金文涛
史玉钊
邢路
秦翰枢
曹锐
谢彬强
JIN Wentao;SHI Yuzhao;XING Lu;QIN Hanshu;CAO Rui;XIE Bingqiang(School of Petroleum Engineering,Yangtze University,Wuhan,Hubei 430100,China;Sinopec Shenli Petroleum Engineering Co.,Ltd.,Dongying,Shandong 257000,China;Safety and Environment Protection Technology Supervision Center of PetroChina Liaohe Oilfield Company,Panjin,Liaoning 124010,China;Jianghan Oilfield Branch of China Petroleum&Chemical Corporation,Wuhan,Hubei 430000,China;Central Sichuan Oil&Gas Field,PetroChina Southwest Oil&Gas Field Company,Suining,Sichuan 629000,China;Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering,Wuhan,Hubei 430100,China)
出处
《钻采工艺》
北大核心
2025年第4期214-220,共7页
Drilling & Production Technology
关键词
井壁失稳
水基钻井液
抑制剂
封堵剂
wellbore instability
water-based drilling fluid
inhibitor
plugging agent
