海上高温高盐高渗透油田污水回注储层性质规律研究

Study on Reservoir Properties of Produced Water Reinjection in Offshore Oil Field of High Temperature and High Salinity and High Permeability

目前,渤海油田已进入开采中期,聚合物驱技术应用范围逐渐扩大。一般条件油藏污水回注规律已被广泛研究,但针对特殊条件油藏与特殊流体,国内外尚未深入。高温高盐高渗透率油藏,由于储层温度高,盐度大等特点,使得污水回注规律与一般油藏相异。通过单一因素变量物理模拟实验,研究了海上高温高盐高渗透率油藏(温度:82℃、矿化度:105 mg/L、渗透率:6000×10^(-3)μm^2)的污水回注规律及控制指标。结果表明,三种污水对渗透率均有伤害,随着残留聚合物、乳化油及固体悬浮物浓度的增大,渗透率伤害率增加。其中,影响最严重的为悬浮物。污水水质的控制指标:残留聚合物≤600 mg/L、乳化油≤50 mg/L、悬浮物≤25 mg/L。

At present, Bohai oilfield has entered the medium stage of oil exploitation. The application of polymer flooding technology has gradually expanded. Sewage reinjection rules in common reservoir has been studied extensively, but for the special reservoir conditions and special fluid, it has not been studied thoroughly yet. Due to the characteristics of high temperature, high salinity and high permeability the rules of sewage reinjection are different from those in common reservoir. Through the single factor variable physical simulation experiment, we study the offshore oilfield sewage reinjection rules and control index under the complex and rigorous condition （Temperature： 82 ℃, mineralization degree： 105 mg/L, permeability： 6000×10-3 μm2）. The results showed that three kinds of wastewater had damage to the permeability. With the increase of the concentration of residual polymer, emulsified oil and suspended solids, the damage rate increased. Among them, the suspended solid has the most serious influence. The water quality control index： the residual polymers〈600 mg/L, emulsified oi1≤50 rag/L, suspended solids≤25 mg/L.