HPAM和疏水缔合聚合物溶液在孤东七区油藏中适应性评价

Adaptability evaluation of HPAM and hydrophobic associating polymer solution in the seventh region of Gudong oilfield

为了解决孤东七区油藏聚合物溶液流变性与注入性的矛盾,筛选适宜非均质强、储层结构疏松等油藏条件的聚合物,在不同长度岩心中开展聚合物溶液渗流实验.在同一岩心上分段测压,建立聚合物溶液注入性评价方法,对HPAM和疏水缔合聚合物的注入性进行评价;在不同长度岩心出口端取采出液,研究该聚合物溶液在近井和油藏深部阻力因数、残余阻力因数以及黏度分布特性.结果表明:注入HJ的压力梯度上升率为16.37MPa.m-1.PV-1,压力梯度稳定值为5.68MPa.m-1,压力梯度上升率和压力梯度稳定值小于相同质量浓度的DH5和B4的值;从提高波及效率的能力和聚合物溶液的流变性来看,疏水缔合聚合物DH5在油藏深部的阻力因数、残余阻力因数和黏度保留率分别为283.86、39.4和0.713,阻力因数、残余阻力因数远大于相同质量浓度的B4和HJ的值;综合注入性和流变性分布评价可知,1.8g.L-1的HJ好于相同质量浓度的DH5和B4的.

In order to solve the contradictions between the rheological behavior of polymer solution and its injectivity,the polymer is selected to suit the reservoir conditions of strong heterogeneity and unconsolidated reservoir structure,and flow experiments are carried out in the cores with different lengths.The pressure of different locations in the same core are measured,and evaluation method of polymer injectivity is established,and the injectivity of HPAM and hydrophobic associating polymer solution are evaluated;the produced fluid is taken out from outlet end of different cores to study distribution characteristics of polymer solution's resistance coefficient,residual resistance factor and viscosity in near wellbore area and deep reservoir.The experimental results show that,the rising rate of pressure gradient of injecting polymer HJ is 16.37 MPa·m-1·PV-1,and the stable value of pressure gradient is 5.68 MPa·m-1,both of them are less than the values of polymer DH5 and B4 with the same concentration.From the ability to improve the sweep efficiency and rheological behavior of polymer solution,the resistance coefficient,residual resistance factor and viscosity reserve rate of polymer DH5 is respectively 283.86、39.4 and 0.713,which are much larger than the values of polymer B4 and HJ with the same concentration.The evaluation result of polymer injectivity and distribution characteristics of rheological behavior shows that polymer HJ whose concentration is 1.8 g/L is better than polymer DH5 and B4 with the same concentration.