中文摘要：

CO2吞吐作为常规油藏的一种有效增产方式,在致密油藏中尚未普及。为研究CO2吞吐在致密油藏的新特征,采用数值模拟的方法,对扩散系数、渗透率、储层非均质性及吞吐周期进行了研究。研究表明,CO2扩散系数在致密油藏中不能忽略,扩散系数的大小影响了最终采收率。对于渗透率越低,储层非均质性越强的致密油藏,采用CO2吞吐增油效果更加明显,而随着吞吐轮次增加,增油效果逐渐减弱。研究新进展对致密油藏优选CO2吞吐增油措施具有一定参考价值。

英文摘要：

CO 2 huff and puff is an effective way to increase product ion in conventional reservoirs,however, this tech nolog yhas not been appl ied to the tight oil reservoirs. With the numerical simulation software CMG , new characteristics of CO2 huffand puff in tight oil reservoirs were studied, including the CO2 diffusion coeffic ient, permeability, reservo ir heterogeneity and huff-n-puff cycle. The results show that CO2 diffusion coefficient cant be igno red in the tighy diffusion coefficient plays an important role on the oil ultimate recovery. For the lower permeability,the stronger the reservoir heterogeneity of the tight oil reservoir is,the more obvious the effect of CO2 huff and puff measure is. Additionally,the incremental oil recovery decreases with an increase in the number of cycle. This work can provide a better understanding of CO2 huff and puff for enhanced oil recovery in the tight oil formation.