深层气藏压裂改造降低施工摩阻技术

摘要

The gas reservoirs in western Sichuan belong to deep to ultra -deep and tight to ultra -tight sandstone reservoirs, featured by high fracture pressure and high extension pressure. Analysis shows that reducing friction resistance will be an effective way to reduce operation pressure. The technology of reducing friction resistance for fracturing deep gas reservoirs has been formed, involving rational pipestring assembly, injection optimization, fiber mixture in frac sand, delayed crosslinking fracturing fluid and prop-pant slug; and the technology has been applied to Well LSI. Integrated techniques of multi - stage slugs, small grain size ceramis-ite, low proppant concentration, low damage fracturing fluid and fiber mixture in frac sand are used to reduce operation friction resistance , as a result, near wellbore friction resistance has been reduced by 9. 47 Mpa, bending friction resistance by 7. 61 Mpa, and on-the -way friction resistance by 4 ~5 Mpa, thus successfully accomplished 80m3 sand fracturing treatment, with post frac gas production of 1. 098 0 x 104mVd and water production 10. 7 mVd.%川西深层气藏属于深—超深、致密—超致密砂岩气藏,储层具有破裂压力高和延伸压力高的特点,经过分析,降低施工摩阻是降低施工压力的有效手段.通过施工管柱合理配置、注入方式优化、纤维加砂、延迟交联压裂液、支撑剂段塞等方式,形成了深层气藏压裂改造降低施工摩阻工艺技术体系,并在LS1井进行现场应用.采用多级段塞、小粒径陶粒、低砂比、低伤害压裂液、纤维加砂等降低施工摩阻集成技术,近井摩阻降低了9.47 MPa,弯曲摩阻降低了7.61MPa,同时延程摩阻降低了4～5 MPa,成功完成了80 m3加砂压裂改造.压后日产气1.098 0×104m3/d,日产水为10.7 m3/d.