基于三线性流模型的致密/页岩油藏水平井统一压裂设计研究

为了优化设计致密/页岩油藏水力裂缝参数,针对传统拟稳态设计方法的局限性,开展统一压裂设计与三线性流模型的结合,得到水力裂缝参数与全流态产能的对应关系。以长庆油田长-7段一口压裂水平井为例,研究得到其最优的裂缝半长为150 m,对应的无因次导流能力为1.84,单缝10年最大累产量为4 015 t。进一步分析可知,给定支撑剂量一定时,当油藏渗透率较低时(如0.001 mD),无因次导流能力较大(>10),产能随着半缝长的增加而增大,更适合造长缝。研究结果对致密/页岩储层压裂优化设计具有一定指导意义。

Study on unified fracturing design of horizontal well in tight/shale reservoirbased on trilinear flow model

In order to optimize the design of hydraulic fracture parameters in tight/shale reservoirs,in view of the limitations of traditional pseudo-steady-state design methods,the unified facture design and the trilinear flow model are combined to obtain the corresponding relationship between hydraulic fracture parameters and full flow state productivity.Taking a fractured horizontal well in the Chang-7 section of Changqing Oilfield as an example,the research shows that the optimal fracture half-length is 150 m,the corresponding dimensionless conductivity is 1.84,and the ten years maximum cumulative production of a single fracture is 4015 t.Further analysis shows that when the given proppant dose is constant,when the reservoir permeability is low(such as 0.001 mD),the dimensionless conductivity is larger(>10),and the productivity increases with the increase of the half fracture length,more suitable for creating long fracture.The research results have certain guiding significance for the optimal design of tight/shale reservoir fracturing.