Condensate Oil And Gas Seepage In Porous Media And The Impact On The Development Of Research

Gas condensate field has taken an important role in the gas field development and its development has been regarded as an urging need in petroleum industry. Study on phase behavior and relative permeability of gas condensate in porous media, as an exploratory subject, rather tough and profound, with high theoretical value and application value, is the foundation of exploitation project establishment for gas condensate reservoir.For quite a long time, it is conducted in the lab to mainly research on phase behavior of gas condensate system in PVT cell to be reference of gas condensate reservoir exploitation performance. However, based on the recent research in the world, the study does not consider the effects of porous media on phase behavior, which is proved by the work of many doctorate dissertations. Besides, the experimental study on gas condensate percolation law in real long core is very insufficient.The following three aspects are highlighted in this dissertation. To begin with, the dissertation systematically studies the common depletion regulation of gas condensate based on the established ultrasonic apparatus. Besides, based on the 4 depletion experiments on high ,middle and low permeability three group core (middle permeability is divided into high speed group and low speed group), the study has found that different development situations in the periods of depletion exploitation make different effects on those important parameters, such as dew point pressure, the change law of the condensate oil critical flow saturation, final natural gas and condensate recovery ratio. In the second aspect of the dissertation, the following steps have been taken: to improve the test produce of normal oil-gas relative permeability curve with considering the effects of included gas; to test the equilibrium condensate oil-gas relative permeability curve to take the sensitivity of velocity analysis to core of middle permeability; to analyze and compare normal oil-gas relative permeability curve to improve the test produce of normal oil-gas relative permeability curve, equilibrium condensate oil-gas relative permeability curve. And finally, based on the previous experiments, we combine the different relative permeability curve in compositional simulator of CMG software to simulating the long core depletion experiments and performance prediction of individual well. Then point out the oil-gas relative permeability curve with considering the effects of included gas can really reflect the rule percolation of condensation oil gas in porous medium. The performance prediction of individual well point out that gas reservoir development has the sensitivity of velocity.The primary achievements of the dissertation are:· The real dew-point pressure of the gas condensate system, CCS and the recovery of condensate and natural gas are all influenced by interstitial water saturation and depletion velocity.