Study on Oil Composition Variation and Its Influencing Factors during CO2 Huff-n-Puff in Tight Oil Reservoirs

With immense potential to enhance oil recovery, CO2 has been extensively used in the exploitation of unconventional tight reservoirs. Significant variations are observed occur oil’s composition as well its physical properties after interacting with CO2. To explore impacts on extraction efficiency, two different types crude (light and heavy oil) huff-n-puff experiments. Moreover, numerical simulation is implemented quantitatively inspect influencing factors including production time, reservoir pressure temperature variation oil. The findings experiments demonstrate that, whether for light sample or sample, hydrocarbon distribution becomes lighter compared original state. In addition, it also discovered that more significant sample. suggest have produced properties. increasing time formation pressure, while heavier temperature. At very beginning production, worsened. Compared state, density viscosity 25.7% 200% higher, respectively. It suggested reducers added into improve this period. continuing continuously promoted. end 3.5% 15.1% lower oil, This paper great significance implementation