Method and system for condensation of unprocessed well stream from offshore gas or gas condensate field

摘要

In a method of condensing an unprocessed well stream from an offshore gas or gas condensate field the well stream taken from one or more wellheads is cooled and directly expanded, isentropically, or near isentropically, to a state in which the pressure is close to that of a storage tank. Part of the well stream is condensed and condensed fractions thereof is drawn off the expander and fed to the storage tank along with condensation products from the exit of the expander. Hence, without any preprocessing, a condensed well stream product is produced which comprises a mixture of liquids and solids which is collected in the storage tank for transport therefrom to land. A system for carrying out the method is also disclosed. The invention makes the condensation of an unprocessed well stream possible without any preprocessing thereof, such as extraction of solid particles, e.g. sands, removal of water, cleaning or drying. Thus, by means of the invention smaller gas or gas condensate fields can be developed in a more cost efficient way.