考虑启动压力梯度和应力敏感的页岩气产能影响因素分析

Influence factors of shale gas productivity considering the start-up pressure gradient and stress sensitivity

根据页岩气渗流机理,分析了页岩气在双重介质中的渗流过程。依据常规双重介质模型,综合考虑了滑脱效应、应力敏感效应及启动压力梯度对页岩气藏产能的影响,建立了考虑解吸、扩散渗流综合作用的页岩气渗流模型,并求得地层压力分布。运用实例分析了页岩气藏产能的影响因素,确定了不同因素对气井产能影响的差异。研究结果总结了页岩气藏单井产能的影响因素,对页岩气藏开发提出了建议。

According to the percolation mechanism of shale gas, the percolation process in the dual medium was ana- lyzed. On the basis of conventional dual medium model, comprehensively considering the influence of slippage effect, stress sensitivity and the start - up pressure gradient on the productivity of shale gas reservoir, a dual medium model considering desorption and diffusion seepage was established. Thus, the formation pressure distribution was obtained. In the examples, differences in influencing factors on shale gas productivity were determined. The factors affecting the productivity of single shale gas well were summarized, and some advices were proposed to the shale gas reservoir development.