聚合物溶液在岩心中的运移阻力

Migration Resistance of Polymer Solution in Cores

聚合物驱技术已在我国大庆、胜利等油田实现大规模工业化应用,成为我国主导的提高采收率技术。聚合物在岩心中的渗流阻力系数是表征其流度控制能力和吸水剖面改善能力的重要指标之一。通过聚合物溶液在不同注入条件和不同长度岩心下的渗流实验,研究了聚合物溶液阻力系数的影响因素及其阻力特性在岩心中的分布特征。实验结果表明,聚合物的相对分子质量、溶液浓度及流速均对阻力系数有显著影响。在低流速下,聚合物的相对分子质量越大,溶液浓度越高,聚合物驱阻力系数越大;在高流速下,聚合物驱阻力系数受聚合物相对分子质量、聚合物溶液浓度、注入速度的综合影响,且不同的聚合物溶液表现出不同的特征。聚合物驱阻力系数、残余阻力系数在长岩心实验中均呈现出注入端数值相对较大,后面各段数值较小且分布均匀的特征。

Polymer flooding has realized large-scale industrialized application in Daqing and Shengli oilfields in China,which has become dominant EOR.Flow resistant coefficient of the polymer in the cores is one of the important indexes of characterizing the capability of mobility control and injection profile improvement.Flow experiments of the polymer in the cores with various length under various injection conditions were made.Ma-jor influence factors of the resistance coefficient of the polymer solution and the distribution features of resis-tance characteristics in the cores were studied.The results show that relative molecular weight,solution concentration and flow rate of the polymer have great influence on the resistance coefficient.At low flow rates,the resistance coefficient increases when the relative molecular weight and solution concentration of the poly-mer increase;While at high flow rates,the resistance coefficient in polymer flooding was influenced by all the factors and different polymers have different features.In the long cores,the resistance coefficient and residual resistance coefficient both are bigger at entrance and then become smaller and uniform.