喇嘛甸油田二类B油层聚驱渗流特征研究

喇嘛甸油田目前注聚对象已全面转向二类油层。与二类A油层相比，二类B油层非均质性严重、渗透率低，已投产的二类B油层聚驱开发效果不理想。为此，开展二类B油层聚驱渗流特征研究。结果表明，随着岩心渗透率的升高，聚合物驱相对渗透率曲线等渗点向右移动，两相跨度增大；提高聚合物相对分子质量和注入质量浓度可使曲线右端点右移，开发效果更好；聚合物驱阻力系数、残余阻力系数随着聚合物溶液质量浓度的上升而增大，随岩心渗透率的降低、相对分子质量的增大而增大；聚合物驱阻力系数与分流率有较好的对应关系，阻力系数出现峰值时，分流率出现峰值，之后高渗透层分流率上升；聚合物相对分子质量越大、溶液质量浓度越高、渗透率级差越大，高渗透层分流率上升越早。

Study on Flow Characteristics of Polymer Flooding in Reservoir B of Lamadian Oilfield

At present, the polymer injection target of Lamadian oilfield has been shifted to the second type reservoir. Compared with the second type A reservoir,the second type B reservoir has serious heterogeneity and low permeability.For this reason,the study on the characteristics of polymer flooding seepage in the second type B reservoir is carried out.The results show that with the increase of core permeability,the iso?permeability point of polymer flooding relative permeability curve moves to the right and the span of two phases increases.Increasing the polymer molecular weight and the injection concentration can make the right end of the curve shift to the right.The polymer flooding resistance coefficient and residual resistance coefficient increase with the increasing of polymer solution concentration and molecular weight,while decrease with the increase of core permeability.There is a good correspondence between the polymer flooding resistance coefficient and the shunt rate.When the resistance coefficient reaches the peak,the shunt rate will reach the peak,and then the shunt rate of the high permeability layer will rise.The higher the molecular weight of the polymer, the higher the concentration of the solution,the greater the difference in permeability level,and the earlier the diversion rate of high permeability layer rises.