【作者】 张伟；

【导师】 夏惠芬；

【作者基本信息】 大庆石油学院 ， 油气田开发工程， 2010， 硕士

【摘要】 油藏经过聚驱后,还有相当数量的石油残留在地层中成为剩余油,经过聚合物溶液驱过的油藏,剩余油在微观孔隙中的分布更加分散,这对聚驱后剩余油挖潜措施提出更高的要求,剩余油在微观孔隙中的存在形态和分布特征是实施四次采油的主要因素,确定聚驱后剩余油分布的形态和分析影响聚驱效果的因素对聚驱后剩余油的挖潜具有重要的理论意义和实际应用价值。本文以压汞实验得到的岩心的孔隙特征参数为依据建立三维孔隙网络模型,借助网络模型将孔隙的微观结构特征与微观渗流机理有机统一,模拟了饱和油、水驱油和聚合物溶液驱油过程,在模拟聚合物溶液驱油过程中主要考虑了聚合物溶液粘度的变化对驱油效果的影响,模拟出聚驱后剩余油的分布形态,分析了孔隙的结构参数与注入参数的变化对聚驱效果的影响,并以可视化仿真物理模型实验验证了模拟结果的正确性;网络模型模拟的结果表明:聚驱后孔隙中的剩余油趋于分散化,但仍以簇状油为主,与水驱后剩余油分布状态比较可以发现簇状油比例有所减少,孤滴状和柱状油的比例有所增加;平均半径较大的孔隙聚驱效果要好于平均半径较小的孔隙;孔隙的形状因子越大,说明孔道的截面形状越规则,越有利于提高驱油效率;孔隙的配位数越大,说明孔隙的连通通道越多,流动性越强,聚驱后剩余油百分含量越低;岩石的润湿性对聚驱的效果起主要作用,水湿岩心要比油湿岩心驱油效果要好;同样,聚合物溶液浓度的提高和驱替压力的加大都能增强聚合物溶液的驱油效果。更多还原

【Abstract】 There is much residual oil remained in the oilfield after polymer flooding, within the area where is flooded by polymer in the oilfield, the residual oil is more decentralization, multiplicity and complexity, which is calling for higher request to the measure of residual oil digging after polymer flooding, it will be having important theoretical supports and application value for residual oil digging after polymer flooding to ascertain the features of residual oil distribution as well as it microscopic affecting factor are studied.The paper was on the base of porosity parameters which is obtained by the pressing mercury experiment of the artificial core, the 3-D network models based on which will be built. By means of 3-D network model, the organic unity of reservoir rock pore structure parameters and the microscopic seepage mechanism are obtained, and simulation the process of oil saturated、first water flooding and polymer flooding. In the process of microscopic polymer flooding simulation, the variation of the viscosity of polymer is mostly considered. Calculating the distribution morphology of the residual oil and analyzing the affecting factor of polymer flooding, the validity is proved by visualization simulation modeling experiment. The result of 3-D network model simulation has show that compared with water flooding the residual oil is decentralization, and mostly of which arranged in the formed of fascicles, but the number of fascicles oil is decrease significantly, island shape and ventilation shape increased. The bigger of the average of the pore radius, the better of the effect of polymer flooding. With the increase of the shape factor, indicating the shape of pore section is more mellow, and it is more benefit to enhance oil recovery. With the increase of the coordination number, the more path pores have, the more smooth of the liquidity of pores, the less of the percentage composition of residual oil after polymer flooding, the wettability is very important to the effect of polymer flooding, the water wetting condition is better than the oil wetting condition. Enhancing the concentration of the polymer and pressure of injection is more availability to polymer flooding.更多还原