The Study of Diffusion in Gas Condensate Reservoirs

Gas condensate around the well in condensate gas reservoirs reduces the efficiency of the well, which can be intensified due to the type of fluid, reservoir and well characteristics. Increasing the production flow and decreasing the pressure at the bottom of the well will increase gas production and, on the other hand, will reduce the pressure and the formation of more condensate. For a maximum output from the reservoir, the output flow rate and bottom pressure must be optimized. One of the production mechanisms of gas condensate reservoirs is the molecular diffusion mechanism. Molecular penetration can affect the efficiency of gas injection or gas recovery in condensate gas reservoirs. Also, fractures in the reservoirs lead to effective routes for the passage of hydrocarbon fluid from the reservoir into the production well. It creates more complex production mechanisms and flow processes. Due to the difference in gas concentration in the matrix oil and the fracture and the convective flow due to the temperature gradient in the vertical fractures, the phenomenon of molecular diffusion will have a unique role in the fracture reservoirs. Moreover, this mechanism in fractured reservoirs, unlike conventional reservoirs, can effectively improve gas injection efficiency in oil reservoirs or natural gas storage. The molecular diffusion mechanism is used in low permeability reservoirs, and reservoirs with relatively high permeability have a pressure gradient of production. This mechanism manifests itself in the long run and controls the rate of storage efficiency, and when the gas comes in contact with oil, it has a more pronounced effect. In other words, the molecular penetration of the liquid phase is of little help. It moves in motion. At the same time, this phenomenon is important in the movement of fluid in the gas phase. The diffusion coefficient is a function of the difference between the penetrating component's concentration, temperature, pressure, and surface tension between the penetrating component and the penetrating medium (between gas and fluid); interfacial tension between the two phases increases and decreases with increasing density.

Keywords:

Gas condensate reservoir , diffiusion , molecular penetration , gas phase , fracure reservoir