Abstract: A plurality of membrane elements are arranged in series within a pressure vessel in which at least two of the elements exhibit different permeances or selectivities for a gas or gas pair respectively.

Abstract: Natural gas may be purified by removing C3+ hydrocarbons and CO2 in respective one or more separation units to yield conditioned gas lower in C3+ hydrocarbons and CO2 in comparison to the un-conditioned natural gas. Notably, the feed gas need not be subjected to joule-thomson expansion and molecular sieve dehydration performed by conventional processes. Rather, any water-rich reject stream from the separation unit(s) is dried downstream with a smaller compressor and smaller molecular sieve or gas separation membrane dehydration unit before it may be re-injected deep underground or deep under the sea bed.

Abstract: Natural gas may be purified by removing C3+ hydrocarbons and CO2 in respective first and second gas separation membrane stages to yield conditioned gas lower in C3+ hydrocarbons and CO2 in comparison to the un-conditioned natural gas.

Abstract: Parallel membrane elements are arranged in parallel within a pressure vessel. A sealing body is disposed within the pressure vessel and is compressed against an inner surface of the pressure vessel to provide a leak-right seal in between a feed gas side of the sealing body and a non-permeate side of the sealing body. The sealing body may be slid within the pressure vessel without damaging the sealing body and in all cases without requiring mechanical assistance.

Abstract: Natural gas may be purified by removing C3+ hydrocarbons and CO2 in respective one or more separation units to yield conditioned gas lower in C3+ hydrocarbons and CO2 in comparison to the un-conditioned natural gas. Notably, the feed gas need not be subjected to joule-thomson expansion and molecular sieve dehydration performed by conventional processes. Rather, any water-rich reject stream from the separation unit(s) is dried downstream with a smaller compressor and smaller molecular sieve or gas separation membrane dehydration unit before it may be re-injected deep underground or deep under the sea bed.

Abstract: Parallel membrane elements are arranged in parallel within a pressure vessel. A sealing body is disposed within the pressure vessel and is compressed against an inner surface of the pressure vessel to provide a leak-right seal in between a feed gas side of the sealing body and a non-permeate side of the sealing body. The sealing body may be slid within the pressure vessel without damaging the sealing body and in all cases without requiring mechanical assistance.

Abstract: Helium-containing natural gas is processed with three gas separation stages to produce a natural gas product and a Helium-containing gas that may be injected into the reservoir from which the Helium-containing natural gas is obtained. A permeate from the first gas separation membrane stage is compressed and fed to the second gas membrane stage. The permeate from the second gas separation membrane stage is recovered as the Helium-containing gas that may be injected into the reservoir. The non-permeate from the second gas separation membrane stage is fed to the third gas separation membrane stage. Non-permeates from the first and third gas separation stages are combined to produce a natural gas product. A permeate from the third gas separation membrane stage is combined with a non-permeate from the first gas separation membrane stage before it is compressed and fed to the second gas separation membrane stage.

Abstract: The invention disclosed relates to feed spacers used in various filtration membrane modules, such as in spiral wound membranes, used in cross-flow filtration. Such spacers have an influence in promoting the mixing between the bulk of the fluid and the fluid element adjacent to the membrane surface so as to keep the membrane surface relatively clean. To optimize these properties, novel spacer designs are disclosed having a plurality of rows of elongated strands, the strands in each row being arranged substantially in parallel to one another, with adjacent rows being attached and disposed at an angle to one another, the strands of at least one row when viewed in cross-section having a central portion of a width smaller than the width of its extremities. Novel membrane modules incorporating such feed spacers are also disclosed.

Abstract: The invention disclosed relates to feed spacers used in various filtration membrane modules, such as in spiral wound membranes, used in cross-flow filtration. Such spacers have an influence in promoting the mixing between the bulk of the fluid and the fluid element adjacent to the membrane surface so as to keep the membrane surface relatively clean. To optimize these properties, novel spacer designs are disclosed having a plurality of rows of elongated strands, the strands in each row being arranged substantially in parallel to one another, with adjacent rows being attached and disposed at an angle to one another, the strands of at least one row when viewed in cross-section having a central portion of a width smaller than the width of its extremities. Novel membrane modules incorporating such feed spacers are also disclosed.

Abstract: A high purity stream of methane can be obtained from crude natural gas, especially exhaust gas from waste landfills, by a process that includes first removing moisture, then feeding the dried crude gas mixture to a gas-liquid contact absorber to strip heavy hydrocarbon compounds in a primarily carbon dioxide by product stream. Methane enriched gas from the absorber is separated in a membrane separation unit which provides permeate enriched in carbon dioxide that is recycled to the absorber and a purified product stream of methane.