Production Characteristics Analysis of CO2 Huff-And-Puff Development in Tight Oil Reservoirs

The tight oil reservoir has large resources, but the reservoir has poor physical properties, and there are problems such as rapid decline in oil recovery rate and low recovery rate after volume fracturing. To solve these problems, taking block X as an example, the production characteristics of CO2 huff-and-puff were numerically studied using CMG software on the basis of experimental data fitting. The results show that: CO2 huff and puff can significantly increase the daily oil production level, with the highest daily oil production increasing nearly four times, significantly improving the recovery rate of tight oil reservoirs; CO2 huff and puff can better supplement formation energy, expand swept volume and improve oil flooding efficiency; Higher oil production can be obtained with higher CO2 injection rate and longer soaking time. With the increase of gas injection rate, the oil production has a certain fluctuation; Under the research conditions of this paper, when the Cumulative oil production is 1500 t/d, the soaking time is 50 d, and the CO2 injection rate is 50 t/d, the effect of CO2 huff and puff mining tight reservoir is better. The research results are helpful to strengthen the understanding of the production characteristics of tight reservoirs developed by CO2 huff and puff.