苏里格桃X区块气藏储层的解水锁剂研究

Study on water lock releasing agent for gas reservoir in Sulige TaoX block

关键词:  气藏  水锁  解水锁剂  渗透率  润湿性

Key words:  gas reservoir  water lock  water lock releasing agent  permeability  wettability

摘要:

目的 随着苏里格气田规模化开发,开采过程中因水锁效应导致的低产低效气井逐年增多,针对苏里格桃X区块生产需求和气藏水锁问题,进行气井储层水锁伤害解除技术对策研究。方法 通过开展室内药剂研究,采用氟碳类和两性离子型表面活性剂、润湿反转剂等体系复配 研制出适合该区块的解水锁剂。结果 苏里格桃X区块渗透率极低,平均含水饱和度45%左右,水锁指数小于0.3,水锁强度中等偏强。解水锁剂能够使岩心的润湿性由亲水逐渐变得疏水,接触角增大10°,有效改变了岩石润湿性且能够降低储层流体界面张力,储层渗透率最终能够恢复至原来的93.86%,现场试验后单井日均增产0.409 7×10⁴ m³。结论 该体系解水锁剂适用于研究区块,能有效解决气井水锁问题。 

Abstract:

Objective With the large-scale development of Sulige gas field, the low production and low efficiency gas wells caused by water lock effect were increasing year by year. Aiming at the production demand of Sulige TaoX block and the problem of gas reservoir water lock, the technical countermeasures for removing the water lock damage of gas well reservoir were studied. Methods Through indoor reagent research, a water locking agent suitable for TaoX block was developed. Fluorocarbon, zwitterionic surfactant and wetting reversal agent were used to prepare water lock agent. Results The permeability of Sulige TaoX block was very low, the average water saturation was about 45%, the water lock index was less than 0.3, and the water lock intensity was medium and strong. The water lock releasing agent water releasing and locking agent can gradually change the wettability of the core from hydrophilic to hydrophobic, increased the contact angle by 10°, effectively changed the wettability of the rock and reduced the interfacial tension of the reservoir fluid. The reservoir permeability can finally recover to the original 93.86%. After the field test, the daily average production increased of a single well is 4 097 m³. Conclusion sThe water lock releasing agent of the system was suitable for the research block and can effectively solve the water lock problem of gas wells.