Hybrid membrane system for gas streams with condensable hydrocarbons

摘要

A gaseous component is extracted non-cryogenically from a feed gas containing condensable hydrocarbons. The feed gas is passed first through a module containing polymeric fibers useful for removing water vapor from the gas. The gas is then passed through a module containing polymeric fibers selected such that they remove some, but not all, of the carbon dioxide in the stream. The gas is then passed through a module containing polymeric fibers selected to remove at least some of the remaining carbon dioxide as well as heavy hydrocarbons, defined as C5 and heavier, from the stream. The invention is especially useful in processing raw methane taken from a well, and in producing methane which is relatively free of water vapor, carbon dioxide, and heavy hydrocarbons.

主权项

1. Apparatus for extracting a gaseous component from a gas stream containing condensable hydrocarbons, the apparatus comprising three distinct modules connected in series, each module comprising a plurality of hollow polymeric fibers,
wherein a first module comprises fibers made of a polymeric membrane which is useful for removal of water vapor from a gas stream, and which is of lesser effectiveness in removing components other than water vapor, wherein a second module comprises fibers made of a polymeric membrane selected such that it removes some, but not all, of carbon dioxide in a gas stream, and wherein a third module comprises fibers made of a polymeric membrane selected such that it removes carbon dioxide and removes heavy hydrocarbons, defined as C5 and heavier, from a gas stream, wherein the polymeric membrane of the third module has a selectivity for carbon dioxide which is less than a selectivity for carbon dioxide of the polymeric membrane of the second module.