新立油田注采比变化规律研究

Study on the trend of injection-production ratio in the Xinli oilfield

结合水驱砂岩油藏注采关系和水驱油规律曲线,推导出4种预测注采比变化规律的数学模型。研究表明,注采比变化过程是水油比(含水率)的单值函数。依据矿场实际和理论分析,总结注采比曲线的5种基本类型,系统分析了储层渗流特征、导压系数、地层压力等因素对注采曲线形态的影响。应用该套方法可以有效预测注采比或含水率的变化,指导低渗透油藏开发动态分析和注水开发方案的制订,具有很好的实用价值。

Four mathematical models for predicting the trend of injection-production ratio are derived for water flooding sandstone reservoirs based on injection-production relationship and water flooding curve.The study shows that injection-production ratio is a single-valued function of water/oil ratio(water cut).Based on field practices and theoretical analysis,5 basic curves of injection-production ratio are generalized,and the impacts of reservoir fluid flow characteristics,pressure transmitting coefficient and formation pressure on the curves are systematically analyzed.The results of this study are of practical value and helpful to prediction of injection-production ratio or water cut,analysis of development performance,and formulation of water flooding program for low permeability reservoirs.