Natural gas cleanup by means of membranes.

This paper deals with the use of membranes for hydrocarbon dewpointing and dehydration of natural gas. Based on experience gained from membrane applications in separating organic vapors from off-gas and process streams, as well as the dehydration of compressed air, membranes have been developed and tested for use in high pressure applications. Membranes and membrane modules have been modified to withstand the high operating pressure. Calculation programs were developed to understand the separation performance and to provide the necessary information for optimizing membrane design. A real challenge was the introduction of the vacuum mode dehydration operation in order to achieve the highest possible dewpoint reduction with minimum methane loss.