Failure Of Gas Condensate In Porous Media And The Gas Injection Process Condensate Oil Saturation Studies

The stady on the laws of phase behavior and percolation of gas condensate system in porous media is a theme which is of difficulty, but of practical and theoretical values.Phase equilibrium and percolation of gas condensate system take place in porousmedia under the earth. Because of interactions between the fluide and the formation media, interfacial phenomena are very strong, so the interfacial phenomenon in porous medium with low permeability can not be especially ignored, and media adsorption, capillary condensation, capillary pressure and so on which are related to interfacial phenomena will affect the phase equilibrium and percolation. Synchronously, there is irreducible water in statum, so irreducible water will affect phase equilibrium and percolation. On the basis of experimental, the paper builds the theoretical models which study the effect of porous medium on phase equilibrium and percolation of gas condensate system and study the the effect of irreducible water on phase equilibrium and percolation with numerical simulation. For the development scheme of condensate gas, the paper studys some schemes about gas recirculation. The main contents are as follows:By analysizing the properties of porous media relates to gas condensate system, the influences of porous media on phase equilibrium and percolation can be considered by media adsorption, capillary condensation and capillary pressure. The paper compares the results about the percolation of condensate gas-oil in porous medium and PVT, and proves the effect of porous medium on the percolation of condensate gas-oil which is very stong. With combining the capillary force and adsorption effect in porous medium, the paper build the mathematical medols of phase equilibrium. Relative to take no account of adsorption effect, adsorption effect can increase the dew point of gas condensate. Adsorption effect can reduce gas recovery, the deviation index of gas and mole content of gas and can increase oil condensate saturation and mole content of oil The paper builds the microscopic visual method to observe the separating and transpirating of condensate gas in man-made core, and study the distributing and transformation of condensate oil saturation in man-made core with depressure. There analyse capillary condensation and capillary pressure about condensate gas-oil system in porous medium.The accordant study result of experiment and numerical simulation is that the critical flowing saturation of condensate oil and oil saturation in porous medium will decrease with increasing water saturation.Based on experiment and numerical simulation, the paper studys the transformation of condensate oil saturation in porous medium with gas recirculation at the point of the most...