Abstract: Throttling separation method is a commonly used gas processing technology, research of condensation characteristics of natural gas is very meaningful. n-pentane is one of the major components in the natural gas liquid. The condensation process of n-pentane in the throttling process is researched using the Eulerian-Eulerian method. According to the condensation characteristics of n-pentane, uniform homogeneous and heterogeneous condensation model in throttling flow is set up. The heterogeneous condensation of n-pentane vapor takes place on foreign nuclei. From the result it is found that the homogeneous condensation of n-pentane can’t occur until critical supersaturation ratio is attained in the throttle, thus heterogeneous condensation plays a dominant role in the condensation process which is completed in a very short time. The initial radius, concentration of the condensation nuclei and the back pressure ratio have a strong effect on the condensation properties of n-pentane. With increase of the initial radius and concentration of the nuclei, the condensation time gets shorter, and the droplet growth rate becomes slow but the total condensation mass increases. As the back pressure ratio increases, droplet growth rate, the total condensation mass and droplet radius reduce simultaneously.

Key words: Heterogeneous condensation, n-pentane, Throttling