氮气泡沫微观驱油机理及剩余油类型实验研究

为了认识氮气泡沫微观驱油机理及剩余油分布特征,利用可视化微观刻蚀玻璃模型,开展氮气泡沫驱油室内实验,通过图像采集技术直观的观察了氮气泡沫的驱油过程及剩余油类型。实验结果表明,泡沫体系中的表面活性剂能有效降低油水界面张力,泡沫能乳化原油,分离油膜,并且在微观上具有良好的封堵效果,进而有效扩大波及范围。泡沫主要驱替水驱结束后残留在孔喉中的柱状残余油及油膜,泡沫驱结束后剩余少量的盲端类剩余油或模型边角的剩余油。因此水驱结束后进行泡沫驱能有效提高稠油油藏采收率。

Experimental study on microcosmic displacement mechanism and remaining oil type of nitrogen foaming flooding

In order to understand the mechanism of microcosmic oil displacement and distribution of remaining oil in nitrogen foam,a visualized micro etching glass model was used to carry out laboratory experiments of nitrogen foam flooding,and the oil displacement process and remaining oil type of nitrogen foam were observed intuitively by image acquisition technology.The experimental results show that the surfactant in the foam system can effectively reduce the oil-water interfacial tension,the foam can emulsify the crude oil,separate the oil film,and have a good plugging effect at the microscopic level,thereby effectively expanding the range of the sweep.The foam mainly displaces the columnar residual oil and oil film remaining in the pore throat after the end of the water flooding,and a small amount of residual oil of the blind end remains after the foam flooding,or the remaining oil of the corner of the model.Therefore,after the end of the water flooding,the foam drive can effectively recover the oil in the heavy oil reservoir.