特低渗透油藏压裂水平井衰竭开采参数优选研究

Optimization of fracture parameters of fractured horizontal well in ultra-low permeability reservoir in the form of natural depletion

为深入系统地研究压裂裂缝各参数对水平井开发效果的影响,应用特低渗透油藏非线性渗流数值模拟软件,以长庆油田某区块为研究对象,给出特定区块的最优裂缝参数,并分析各裂缝参数的敏感性。结果表明,在特定储集层渗透率条件下,压裂水平井具有最优的水平井长度、裂缝形态、裂缝条数、裂缝长度、裂缝导流能力;通过不同渗透率级别和水平井长度下的裂缝参数优选可知,对于压裂水平井衰竭开采效果最为敏感的参数是裂缝条数,其次是裂缝长度,裂缝导流能力最为不敏感。

In order to investigate the effect of fracture parameters of fractured horizontal well on the natural depletion result of ultra-low permeability reservoir,a block in Changqing Oilfield is stimulated numerically using nonlinear seepage numerical simulation software for ultra-low permeability reservoir,the optimal fracture parameters of the block are grained,and the sensitivity of the fracture parameters to the natural depletion result of ultra-low permeability reservoir is analyzed. It is shown that,under certain reservoir permeability,there are optimal horizontal well length,fracture pattern,fracture number,fracture length and fracture flowing capacity. The optimization of fracture parameters under different reservoir permeability grades and horizontal well length show that the fracture number is the most sensitive to the natural depletion result of fractured horizontal well in ultra-low permeability reservoir,the fracture length is secondary,and the fracture flowing capacity is the most insensitive.