摘要
一般低渗透储层只有存在大量的天然裂缝才能经济有效的进行开发。由于毛管力的作用,油从岩心基质自发渗吸到裂缝中是一种十分重要的采出机制。因此,在评价低渗透油藏石油采收率时具有重要作用。实验采用长庆油田低渗透储层天然岩心,进行自发渗吸实验。实验结果表明,渗透率(0.1～1.0)×10-3μm2级别的岩心,渗吸采收率在11%～12%之间;渗透率(2～4)×10-3μm2级别的岩心,渗吸采收率在14%～18%之间。同一块岩心不同渗吸液对比实验表明,活性水因降低了界面张力而显著提高的石油采收率,增幅可达10%。
Usually the low permeability reservoir could be developed sufficiently when existing abundant nature fracture. As the capillary force action, it is an important mechanism that the oil flow into the fracture from matrix. So this phenomenon should be considered in estimating the oil recovery. This paper bases on the laboratory experiment, using the nature low permeability core of Changqing Oilfield. The result shows the oil recovery increases with the permeability obviously.The spontaneous imbibition recovery efficiency of two cores, one is between 11 percent and 12 percent, the other is between 14 percent and 18 percent. The same core results indicate that using the different surfactant solution could get a higher recovery because the active water decreases the boundary tension.
出处
《复杂油气藏》
2009年第1期54-56,共3页
Complex Hydrocarbon Reservoirs
关键词
低渗透
岩心
自发渗吸
采收率
low permeability
core
spontaneous imbibition
recovery efficiency
