低损害无固相复合聚合物修井液体系研制及性能评价

在修井过程中,低压低渗裂缝较发育储层易发生修井液漏失,造成水敏、液锁等损害。为使该损害降至最低,采用动态挂片失重法、页岩抑制防膨法及表/界面张力和流变参数测定方法,优选出了适合储层特点的缓蚀剂、黏土防膨剂、表面活性助排剂及增黏降滤失剂等修井液组分,得到最佳修井液XJPS配方：模拟地层水＋1%GH1＋0.3%HTB＋2%DG-FPJ＋0.3%XC＋2%JMPS-1＋1%PRDS＋2%NaCOOH＋0.3%NaOH。室内实验结果表明,该修井液具有流变参数适宜、低滤失（〈8 mL）、渗透率保留率高（〉85%）、返排效果好等特点,可以实现修井液在无固相、不形成致密泥饼下的低滤失性能。矿场应用效果表明,与原用修井液相比,试验井应用XJPS修井液作业后,日产气量、日产油量降幅和含水量增幅均较小,明显减轻了因修井液漏失储层造成的液锁损害和产能损失,提高了储层保护效果和修井效率。图2表7参8

Research and Laboratory Evaluation on a Novel Low-Damage and Solid-Free Combinational Polymer Workover Fluid

Fluid-blocking and water sensibility were easily induced by workover fluid loss during the processes of workover operations in the low-permeability gas condensate reservoir formation with low formation pressure of natural micro fractures.In order to minimize the damage,the main additives suited to target formation were selected by rotating hanging plate and dynamic weight loss method,and so on.The best formula of the XJPS workover fluid was: 0.3% XC,2% JMPS-1,1% PRDS and supplementary additives.The results ...