吉林油区天然气藏富含CO_2,且存在底水和裂缝。气-水相渗流特征室内实验结果显示,气-水相渗曲线形状及特征点数值与实验条件密切相关。在相同的岩心条件下,温度、压力或CO_2体积分数越高,则水相相对渗透曲线偏离坐标原点越远,而两相渗流区域也越宽;同时等渗点向右上方移动,且束缚水饱和度越低,则气相相对渗透率上升越快,束缚水饱和度下的气相相对渗透率值也越大,从而更有利于气-水两相渗流。
Gas reservoir has high content of CO_2 in Jilin oilfield and is filled with cracks and bottom water. The percolation characteristics of gas and water should be studied; meanwhile,the gas production rate should also be controlled. The laboratory experiment results show that the shapes of gas- water relative permeability curves and the values of feature points are related to the experimental conditions. In the case of the same core,the higher the temperature,the pressure or the content of CO_2 is,the lower the irreducible water saturation is; and the faster the gas relative permeability rises,the better the seepage of gas- water is.