New developments in nucleation theory and their impact on natural gas separation

Conventional separators in the oil industry use a feed of oil and gas in two-phase multi-component equilibrium. Recently a new concept of separators has been introduced which can be fed with a single-phase gaseous mixture. The separator combines a quasi-isentropic expansion of the gas during which liquid droplets are formed by the nucleation process and a gas-liquid cyclonic separator. The performance predictions of such a separator depend critically on an adequate description of nucleation phenomena. For a large number of practical cases the Classical Nucleation Theory is very inaccurate. The recently proposed Mean-field Kinetic Nucleation Theory yields quantitatively accurate predictions of nucleation behavior of various microscopically diverse substances. An important advantage of non-equilibrium separation is the minimal use of chemicals and absence of regeneration systems, as opposed to conventional separation methods such as glycol contactors or silica gel towers.