Method of maintaining constant the composition of a product stored in a low temperature liquefied gas store

摘要

A method for maintaining constant the composition of liquefied gas in a store (1) comprises extracting product in its gas phase from the store by means of a compressor (8) to raise its pressure. The gas is then cooled in a first heat exchanger (9) and then in a second heat exchanger (10), to a final temperature such that on expanding the gas into a tank (11) most of it is liquefied. The small amount of remaining gas is recycled to the compressor inlet after passing through the first heat exchange as its cooling fluid. The product is also extracted in its liquid phase (3) by a pump (19). The liquid is then passed through a battery of pumps (20) which raise it to a pressure high enough for a distribution network to be directly supplied therewith (after vaporization). A portion of the highly compressed liquid phase is used as the cooling fluid for the second heat exchanger (10).