低渗储层压裂技术应用效果评价

RESULT EVALUATION OF FRACTURING TECHNIQUES FOR LOW PERMEABILITY RESERVOIRS

低渗油气藏难采储量的动用对油气田的增产、稳产日趋重要 ,储层的压裂改造己成为开采低渗储层的重要手段。针对苏北盆地溱潼、金湖凹陷阜宁组低渗油气藏断块碎小、储层物性差、层多且厚度薄的特点 ,利用全三维压裂软件对拟压裂井的压裂液体系、压裂裂缝参数、射孔方案等进行优化 ,并进行压前预测评估。矿场应用表明 ,在压裂中采取的限流压裂、避射、高效助排等压裂工艺技术对阜宁组低渗油气藏储层改造效果明显 ,尤其是对自然产能低、开发效果差的油气井运用效果更显著 ,压裂成功率和有效率提高了 5 %和 8% ,平均单井有效期延长了 3.1个月 ,单井平均增油 4 6 4t,取得了较为明显的增产效果 ,目前己形成了适合本区油气田开发的多项压裂工艺 ,并对类似油气田的压裂改造具有指导意义。

Mobilizing the hard-recovering reserves of low permeability reservoirs is more and more important for the increasing and stable production of oil and gas fields. Reservoir fracturing has become the major tool to exploit the low permeability reservoirs. Aiming to the characteristics of the low permeability reservoirs with small faulted blocks,poor physical property,and thin multiple beds in Funing group of Qingtong and Jinhu sags,Subei basin,the fracturing fluid system,the fracturing parameters and the perforation program are optimized for the planned fracturing wells with full 3-D fracturing software. And the predictive evaluation is conducted before fracturing. The field application shows the techniques,such as limited flow fracturing,avoiding perforation,and effective clean-up,etc. have obvious benefits for the low permeability reservoirs of Funing group,especially for the oil and gas wells with low natural productivity and poor production. The techniques make the success rate and the effect rate of fracturing increase 5% and 8% respectively. The average effective term for a single well expands 3.1 months. The average production for a single well increases 464 t.,which is obvious benefit. Now,many fracturing techniques suitable to oil and gas field development of this area have been formed. Also,they are the guide for fracturing of similar oil and gas fields.