油田低产低效井酸化增产酸液体系配方

Formulation of Acidizing Stimulation Acid System for Low Production and Low Efficiency Wells in oil field

为解决低渗储层长水平段水平井分段压裂工艺技术问题,以鄂尔多斯盆地东缘某油田为实例,通过实验分析了山西组储层敏感性,基于岩石力学参数分析了储层闭合压力梯度。研究表明:山西组储层具有中等偏强水敏损害,闭合压力梯度为0.0198 MPa·m-1。以M-1水平井为例设计了10段压裂工艺,采用套管射孔和可钻复合桥塞实现分段压裂,优化低浓度瓜胶压裂液体系,其具有悬砂能力强、耐温抗剪切性能好、储层保护性能好的优点。利用三维压裂软件模拟,人工裂缝缝长60.8 m、支撑缝长55.8 m,反映出压裂过程造缝能力较强、裂缝延伸距离较远,达到了水平井分段压裂设计目的。

In order to solve the problem of staged fracturing technology for long horizontal wells in low permeability reservoirs,taking an oil field in the eastern edge of Ordos basin as an example,the reservoir sensitivity of Shanxi formation was analyzed through experiments,and the closed pressure gradient of the reservoir was also analyzed based on the rock mechanics parameters.The results showed that the reservoir of Shanxi formation had moderate to strong water sensitivity damage,and the closure pressure gradient was 0.0198 MPa·m-1.Taking M-1 horizontal well as an example,a 10-section fracturing process was designed,in which casing perforation and drillable composite bridge plug were selected to realize staged fracturing,and low concentration guar gum fracturing fluid system was optimized,the optimized fracturing fluid system had the advantages of strong sand suspension capacity,good temperature and shear resistance,and good reservoir protection performance.The three-dimensional fracturing software simulation results showed that the length of artificial fracture was 60.8 m and the length of supporting fracture was 55.8 m,reflecting that the fracture making ability of the fracturing process was strong,and the fracture extension distance was far,which achieved the purpose of staged fracturing design of horizontal wells.