FS-3井异常高温储层压裂改造技术

Application of fracturing technology in the abnormal high temperature reservoir of the well FS-3

FS-3井是位于济阳坳陷构造带上的1口埋藏深、裂缝发育的异常高温井,对储层改造施工的压裂液以及对地层破裂压力的预测等都提出了极高的要求。针对FS-3井的地质特征进行了储层改造的技术难点分析,在大量实验测试的基础上,优选出耐高温、高黏度且能满足150℃高温的低摩阻延迟交联液体系。通过室内岩心实验,利用储层应力计算模型预测了地层破裂压力和压裂施工压力。同时,采用粉砂降滤失、大排量施工、适当增加前置液用量、前置液阶段伴注液氮帮助返排等技术措施,完成了FS-3井的压裂施工设计,并进行了现场实施。最后,利用压裂施工曲线、压后排液及压后产量测试资料,完成了FS-3井压裂施工资料的评估分析,达到了预期效果。该成果对异常高温储层的压裂改造设计和施工方案的形成具有指导意义。

The well FS-3,located in the structural belt of Jiyang sag,is ultra-deep and targets to the reservoir with abundant fractures and abnormal high temperature,thus it presents a high requirement for fracturing fluid and formation fracture pressure forecast.Technical difficulties in reservoir stimulation have been analyzed according to the geological characteristics of the well FS-3,a system of low friction resistance and delayed crosslinked fracturing fluid with high viscosity even at the temperature as high as 150℃ was optimized on basis of substantial experimental data.Through core experiment,formation breakdown pressure and pumping pressure were calculated using the reservoir stress calculation model.Meanwhile,other technological measures including fluid loss agent,high pumping rate,high pad volume,and injecting liquid nitrogen were adopted in the design of fracturing program,and fracturing operation was successfully carried out in field conduct.Finally,the effect of fracturing treatment was proven to be good through fracturing curve evaluation and the analysis of postfrac fluid flowback and gas flow rate.It shows that this study is quite significant to the design of fracturing treatment and construction program.