Abstract: The present invention is directed to a method for removing a higher purity sidestream of a product gas from a main product pipeline gas flow stream of lower purity using a membrane selective for the product gas in contrast to impurities contained in the main product pipeline gas. The process avoids capital intensive apparatus or energy intensive processing and returns the reject gas from the membrane to the pipeline for inclusion with the main product pipeline gas. Recovery of a higher purity component of a main pipeline product gas containing that component is also contemplated.

Abstract: A process is provided for the low temperature separation of a high purity gas product at lower power requirements by permeating a feed gas stream through a membrane having a water-to-gas-product selectivity of at least about 100, separating water from the gas stream, feeding the partially dried gas stream through a molecular sieve to remove residual water, and supplying the dried gas stream to a low temperature separation unit to separate gas product(s) from the gas stream.

Abstract: A permeator system for separating at least one gaseous component from a feed gas mixture containing at least one other component using a semi-permeable membrane is disclosed which maintains high permeate product purity and desired component recovery during periods of turn-down in capacity. In accordance with the present invention, the permeator system contains a series of flow and pressure sensors and valves which regulate differential pressure across the membrane based upon permeate product demand or feed availability.