采用新型X射线装置研究礁灰岩渗流特征

针对礁灰岩油藏复杂的渗流特征,实验采用了一种新型的X射线装置;该装置是美国Coretest公司生产的XRSC—198 X射线线性扫描仪,它不仅可以完成常规的高温高压驱替实验研究,也可以进行岩芯驱替过程中流体饱和度和相渗曲线的测试。研究采用的是LH11-1礁灰岩油田取得的岩心,利用XRSC—198 X射线线性扫描仪开展了组合长岩心初期水驱油驱替实验和50倍水体驱替实验。研究了储层岩心水驱油两相渗流特征、驱替效率以及相渗特征。采用X射线扫描方式得到了驱替各个阶段含水饱和度分布情况。实验结果显示,对于礁灰岩油藏初期水驱阶段采收率较高,后续通过高倍水驱的方式也可以采出较少的剩余油。通过X射线扫描可以发现随着注入端流体的注入,X射线强度不断减弱,可以得到较明显的驱替前缘特征。在高倍水驱阶段,X射线强度变化很小,说明岩心内流体饱和度变化较小,原油采出较少。

Study on the seepage characteristics of reefreservoir using a new X - ray device

In view of the complicated seepage characteristics of reef reservoirs, a new type of X - ray device is used in the experiment. The device is XRSC - 198 X - ray linear scanner produced by the Coretest, it can not only complete the conventional high temperature and high pressure displacement experiment research, can also carry out the core displacement process of fluid saturation and relative permeability curve test. This study carried out a combination of long core initial water displacing oil experiment and 50 times water flooding experiments using XRSC - 198 X - ray linear scanner which the core come from LH11-1 reef reservoir, studied the reservoir rock two-phase flow characteristics, displacement efficiency and permeability characteristics. The experimental results show that the recovery of the early flooding is high, and the subsequent water flooding can also produce less residual oil. By X-ray scanning, it can be found that with the fluid injection, the X - ray intensity is weakened, which can get obvious displacement front edge. In the high water flooding stage, the X - ray intensity change is very small, which indicates that the change of fluid saturation in the core is a little and the oil production is less.