低渗透油藏水平井裂缝参数优化研究

Optimization of fracture parameters of horizontal well in low permeability reservoir

低渗透油藏经常采用水平井压裂的方法来实现油井增产,而合理的水平井裂缝参数设计能充分发挥人工裂缝的增产作用。以江苏油田M断块地质特征和目前开发状况为基础,抽象出相应的机理模型,应用数模软件的门限压力建立了考虑启动压力梯度影响的水平井压裂模型,并与PEBI网格加密法的水平井模型进行了对比。结果表明:启动压力梯度对模拟结果影响相对较大,而裂缝形态对模拟结果的影响相对较小;M断块水平井最优裂缝间距为90 m,最优裂缝条数为6条,最优裂缝半长为130 m。该研究成果为江苏油田M断块水平井裂缝参数优化提供了思路与借鉴。

Fracturing of horizontal well is often applied to increase oil well productivity in low permeability reservoir, and reasonable design of fracturing parameters of horizontal well can give full play to the role of increasing productivity of the artificial fracture. This paper abstracted the corresponding geological model on the basis of reservoir geological characteristics and the present state of exploitation in M fault block in Jiangsu Oilfield, established fractured model of horizontal well considering start-up pressure gradient by using threshold pressure of Eclipse application software, and contrasted with the PEBI grid and block grid model of horizontal well. The result shows that compared with the start-up pressure gradient, the fracture shape has a relatively small influence on the simulation results. The optimal fracture interval is 90 m, the optimal fracture number is 6, and the optimal fracture half-length is 130 m. This study provides a reference for optimization of the fracture parameters of horizontal well in Jiangsu Oilfield.