低渗油藏不等产量源汇合理注采井距影响因素分析

The analysis of effects on rational injection-production well spacing for unequal production of source-one and production-one in low permeability reservoir

低渗透油藏合理井距的确定必须考虑启动压力梯度的影响。根据等产量一源一汇渗流理论,推导出不等产量一源一汇主流线上启动压力梯度最小值,结合启动压力梯度与渗透率关系建立了低渗透油藏合理注采井距确定方法。通过实验及影响因素分析确定注采压差、地层渗透率和注采比对合理注采井距影响关系,得出不等产量一源一汇,最小压力梯度的位置与注采比的大小有关,注采比对合理井距影响较小,储层改造对提高合理井距经济可行。

Fluid flows in low permeability reservoir exists threshold pressure gradient,according to the theory of flowing through porous media for the production-one and source-one convergence point the calculation formula for the minimum start-up pressure gradient of the channel line in the flooding.Deducing unequal production for the production-one,source-one convergence point the calculation formula for the minimum start-up pressure gradient of the channel line in the flooding.Integrating the relation between the start-up pressure gradient and the permeability,the determination method of the reasonable injection-production well spacing for the low permeability reservoir is established.Through experiments and analysis of influencing factors,determining the injection-production pressure acquiring pressure, formation permeability and injection-production ratio for the influential diagram of rational injection-production well spacing.As for unequal production of source-one and production-one,the position of minimum pressure gradient is related to the size of production-injection ratio.It doesn＇t greatly influence rational injection-production well spacing.Reservoir stimulation to improve the reasonable well spacing is more economical and practical.