低渗透气藏分层压裂难点及对策

Difficulties of separate layer fracturing technology for low permeability gas reservoir and its countermeasures

在目前的油气资源中,难动用储量所占的比例日益增大,且多数都具有储层层系多、间距小及物性条件差等特点。因此,分层压裂工艺已成为此类油气藏投产、增产的主要方法。但目前分层压裂存在着改造风险性高、难度大、增产效果不明显等难题。结合川西苏码头构造的气藏地质实际,分析了A、B两口典型施工井在分层压裂中存在的问题,从地质资料分析、缝高控制、低伤害压裂液优选及分层压裂工艺设计优化等方面,提出了低渗透气藏分层改造的关键技术对策。

The proportion of difficult-to-produce reserves are graduallY increasing in oil and gas resources, and most of them have the characteristics of multiple layer systems, small interspace and poor physical property of reservoirs. The separate layer fracturing technology is an essential method for commissioning and stimulation of this kind of reservoir. However, there are some difficulties of separate layer fracturing on high risk, great difficulty and inapparent stimulation effect. Combined with the geologic situations for the gas reservoir of Sumatou Formation in western Sichuan, this paper analyzes the problems existed in separate layer fracturing of Well A and B, and proposes the countermeasures for improving the high efficiency fracturing technology for low permeability gas reservoir from the aspects of obtaining the geologic data, controlling fracture height, optimizing the fracturing fluid and separate layer fracturing technology.