甜菜碱/聚合物二元体系驱油性能研究  

A Study on Oil Displacement Efficiancy of Betaine/Polymer Binary Solutions in Produced Water

作　　者：郭明日[1,2] 吴文祥[1] 唐佳斌[1] 

机构地区：[1]东北石油大学石油工程学院,黑龙江大庆163318 [2]中国石油大庆油田第六采油厂,黑龙江大庆163114

出　　处：《油田化学》2011年第4期435-439,共5页Oilfield Chemistry

基　　金：国家重点基础研究发展计划(973计划)"化学驱和微生物驱提高石油采收率的基础研究"(项目编号2005cb22130-G)

摘　　要：在模拟大庆油田条件下测定了0.5、1.5、2.5 g/L聚合物污水溶液的黏度、储能模量G'和损耗模量G″,由G'和G″按文献公式计算了溶液的第一法向应力差N1;用以表征黏弹性溶液的弹性时,频率10 Hz下的N1值比G'值要明锐些。用聚合物浓度0、0.5、1.5、2.5 g/L,表面活性剂(磺基甜菜碱BS)浓度0～0.3 g/L的16个实验驱油体系连续驱替油饱和的含水中性润湿人造岩心,由驱替压力梯度和实测油水界面张力计算了毛管数,考察了采收率与聚合物浓度关系(等毛管数条件)和采收率与表面活性剂浓度关系(等聚合物浓度条件),结果如下:为达到同一毛管数值(数量级)所需的表面活性剂浓度随聚合物浓度增大而略有减小;适宜浓度聚合物不影响表面活性剂的驱油效率,而且可提高采收率;聚合物浓度超过适宜值范围会降低表面活性剂和聚合物本身的驱油效率;聚合物浓度适宜范围的上限随毛管数增大而减小,亦即随油水界面张力减小而减小。The apparent viscosity,and the storage and loss moduli,G′and G″,of 0.5,1.5,and 2.5 g/L polymer solutions in produced water were determined and the first normal stress difference,N1,was calculated from the G′and G″ data using an equation published in literature else where.The N1 value at frequence 10 Hz was more distinct in solution elasticity characterization than the G′ value did.16 experimental flooding fluids composed of 0,0.5,1.5,and 2.5 g/L polymer and 0-0.3 g/L surfactant（sulfo betaine BS） were used to flood the oil saturated and water containing artificial cores of neutral wettability;the capillary number,Nc,of the cores for every flooding fluid was calculated from the flooding pressure gradient and the oil/water interfacial tension determinations;the percent oil recovered from the cores was studied in relation to polymer concentration at equal capillary number and to surfactant concentration at equal polymer concentration.All experiments were conducted under simulation conditions of Daqing oil field.It was shown that the surfactant concentration needed to reach a given Nc level decreased with increasing polymer concentration;the polymer introduced into the flooding fluids in proper concentrations did not affect negatively the oil displacing efficiency of surfactant but enhanced the oil recovery;excess amount of polymer introduced would reduce the oil displacing capabilities of both surfactant and polymer itself;the proper polymer concentration range was interconnected with Nc to some extent and its ceiling value decreased with increasing Nc,or with decreasing oil/water interfacial tension.

关 键 词：驱油效率 毛管数 界面张力 表面活性剂/聚合物二元体系 组成与配方研究 黏弹性 甜菜碱表面活性剂 大庆油田 

分 类 号：TE357.46[石油与天然气工程—油气田开发工程]