摘要
为了解决油层伤害问题,克服已有技术的缺陷,提出了非渗透钻井液的概念,并就非渗透钻井液进行了实验研究,同时开展了现场试验。室内研究和现场应用表明:非渗透钻井液体系由于主处理剂的特殊胶束结构,具有较宽的粒径范围和可变形的特性,能够用同样的流体成分有效封堵不同的渗透地层,增大地层的破裂压力,加宽钻井液密度窗口,密封渗透性地层和页岩中的微裂缝;可用同样的流体过平衡钻开储层和完井,成功地解决了裂缝地层的井壁稳定问题、复杂压力层系井的井漏、压差卡钻和各种复杂油气田油层伤害等问题;由于非渗透处理剂可以在孔喉中快速形成低渗屏蔽层,有效地阻止液体侵入,因而具有优良的油气层保护性能。非渗透处理剂与其它油层保护剂相比,其显著优点在于其中的聚合物形成的胶束只有在高于聚合物临界浓度下存在,因而当这种聚合物与洗井液接触或在采油过程中与储层流体接触时,其屏蔽层不再存在,有利于提高油井产能。
The concept of 'Non-invasive drilling fluids'(NIF) was proposed to solve problems of formation damage, and the NIF was studied in lab and tested on rig-site. Evidence in lab and field showed that the NIF has advantages including: 1) as the main treating agent exhibits characteristics of particular micelles structure, wide particle distribution and deformability, it effectively seals formations of different permeability with one component, increases formation fracture pressuse, widens drilling fluid density window, and seals micro-fracture of permeable formation and shale stone; 2) reservoir interval drilling and well completion are completed with one fluid under over-balanced pressure, solving problems such as hole stability in fissured formation, lost circulation and pipe stuck in complicated pressure formation and other issues relating to reservoir damage. Comparing with other oil layer protecting agents, the superiority of the non-invasive treating agent lies in that the micelles exist only in a solution of the concentration higher than the critical point, and when the polymer meet flushing fluid or formation fluid, the barrier disappears, which is benefit for well productivity increasing.
出处
《钻井液与完井液》
CAS
北大核心
2005年第2期1-3,共3页
Drilling Fluid & Completion Fluid
