江汉油田黄场区块泡沫酸化室内研究

Research on Foam Acid and Its Acidizing Effect in Huangchang Block of Jianghan Oilfield

江汉油田黄场区块油层渗透率差异系数大，储集层平均有效孔隙度为13．9％，属低孔低渗细喉型孔隙；地层原油饱和压力为4．33MPa，地层压力为27．55MPa，平均地层压力系数为0．75，地层温度为65℃；属典型的三低地层；属于中等偏强的水敏、中等偏强盐敏。通过试验优化出了适应本区块特点的新型泡沫酸体系，即：18％HCl＋20％SDS＋（1．1％～1．2％）HPAM＋（0．7％～0．8％）ADA＋（0．1％～0．3％）ATA。室内双岩心酸化效果评价试验结果表明：该泡沫酸对渗透率较小的岩心的渗透率提高倍数是用土酸时的9．3倍，这充分说明了该泡沫酸能够有效封堵相对较高渗透层，使酸液转向分流进入相对较低渗透层，达到全面酸化的目的。用该泡沫酸体系和土酸进行了室内岩心酸化分析，发现该泡沫酸明显优于土酸体系。

A foam acid was developed for acidizing operations in Huangchang Block of Jianghan Oilfield taking in consideration of the character of low value and widely varied range of formation permeability,low porosity,strong effect of water trapping.Compared with the core acidizing tests in lab conducted with mud acid,this foam acid showed evident priority on acidizing effect and on damage prevention.