稠油非线性渗流测定方法研究

Experimental study of nonlinear seepage for heavy oil

汪伟英 喻高明 柯文丽 王雨 戈月

Wang Weiying Yu Gaoming Ke Wenli Wang Yu Ge Yue

长江大学(武汉)石油工程学院, 武汉 430100 2. 油气资源与勘探技术教育部重点实验室(长江大学), 武汉 430100

Petroleum Engineering Institute, Yangtze University (Wuhan Campus), Wuhan, Hubei 430100, China 2. Key Laboratory of Exploration Technologies for Oil and Gas Resources(Yangtze University), Wuhan, Hubei 430100, China

稠油由于其非牛顿特性,在多孔介质中的渗流特征与常规原油不同,一般表现为非线性渗流,其特征之一是可能存在启动压力梯度,只有当驱替压力梯度超过启动压力梯度时稠油才开始流动,且渗流规律偏离达西定律。通过室内实验研究,设计了合理测量启动压力梯度的方法。利用天然岩心与实验室配制的模拟油,设定不同的驱替流量来测量启动压力梯度,研究实验测量启动压力梯度过程中驱替流量对测量结果的影响。结果表明,当驱替流量超过某一临界值时,测量得到的启动压力梯度会受到驱替流量的影响。因此,在测量岩心真实启动压力梯度的过程中,实验方法和驱替流量的选择不容忽视。

Due to the non-Newtonian behavior of heavy oil, the seepage characteristics in porous medium are different from conventional crude oil. They usually seep in nonlinear ways and there might exist threshold pressure gradients. Only when the displacement pressure gradient is greater than the threshold pressure gradient, heavy oil begins to flow, and the seepage rule deviates from Darcy's law. Through laboratory experiments, this paper designs a method for measuring threshold pressure gradient appropriately. Natural core samples and simulated oil are used to measure threshold pressure gradient by setting different flow rates. In this way, the impact of flow rate on threshold pressure gradient is studied. The results show that the threshold pressure gradient would be affected when the displacing rate exceeds a critical value. Therefore, in the process of measuring real threshold pressure gradient of a core, the choice of experimental method and displacing rate can not be ignored.

https://doi.org/10.11781/sysydz201304464