ON MIST FORMATION IN NATURAL-GAS

Mist formation that occurs during production, handling, and transport of natural gas is shown to be the result of non equilibrium thermodyna mic processes. A simple analysis is presented of these nucleation and droplet growth phenomena in natural gas, and an estimate is given of t he rate at which droplets are formed for typical process conditions. A model of droplet growth due to condensation is presented. The nucleat ion and condensation behaviour of two samples of a natural gas is inve stigated in a Wilson expansion cloud chamber for the initial pressure range of 5 to 50 bar and initial temperatures of 294-297 K (21-24-degr ees-C). For a cooling rate of about 1 K/ms, a typical undercooling at the onset of condensation is found of 32 +/- 3 K and 60 +/- 5 K respec tively for the two samples, which emphasizes the importance of non-equ ilibrium effects.