相渗透率研究是油田开发方案编制和生产管理不可缺少的基础工作,在注水开发油田中,由于中轻质油田相对稠油油田具有较长的无水采油期或低含水期,而常规的非稳态实验中相渗数据点在中高含水饱和度处较为集中,因此采用此方法获取的相渗数据直接应用到中轻质油田生产动态分析及数模拟合中误差较大。针对以上问题,对渤南区域中轻质油田分别采用稳态与非稳态两种实验方法获取相渗数据并开展研究,结果表明:当地层原油黏度小于6 mPa·s时,两种实验方法结果差异较大,宜采用稳态法;当原油黏度高于6 mPa·s时,差异可忽略不计,宜采用非稳态法代替稳态法。研究发现,非润湿相黏度、沉积相特征、润湿性、温度等因素对中轻质油藏相渗曲线形态及含水上升规律都有不同程度的影响,在油田开发研究中应综合考虑。

The relative permeability curve is the basis for studying the two-phase flow in reservoir. It is an indispensable and important data for numerical simulation and dynamic analysis of oilfields.At present, the researches on the relative permeability both domestic and overseas were mainlygiven priority tothe methods of dealing with the relative permeability data or the application of the relative permeability curve, the paper about the experimental methods was likely rare.For the moment, the most immediate method for obtaining the data of relative permeability is the experimental of non-steady-state. This method is simple to operate with short time and has universal applicability. However, since the experimental points of non-steady state method are often concentrated after oil and water both coming out, resulting in the data of the oil-water front are less. The impact is relatively small for the heavy oilfield, but for medium-light oil fields, it cannot be ignored.The viscosity ratio of water-oil in medium-light oil field is relatively high, the fractional flow rate curve has a stronger concave shape.Compared with the heavy oilfield, those oilfields have a longer water free production or lower water cut periods with same physical conditions and development methods. The non-steady state method application in medium-light oil field may cause deviation, resulting in difficulties to accurately understand the law of water rising.In this paper, the steady-state and unsteady state method were used to obtain the relative permeability data.The results show that the two methods are quite different when the viscosity of the crude oil in the formation is less than 6 mpa·s.Steady state method should be adopted. When the viscosity is higher than 6 mpa. s, the difference can be ignored and non-steady state method should be adopted instead.Based on the above-mentioned interpretation, the research on the main controlling factors influencing the relative permeability of medium-light oil fields was carried out.The results show that the viscosity of non-wetting phase, the characteristics of sedimentary facies, the temperature and wettability played important role on the phase-permeability curve and the law of water rising.This article dedicates to give a complete description on relative permeability curve in medium-light oil field, which is of great significance for numerical simulation and dynamic analysis.