A system for producing steam includes a steam generator with steam output; a membrane filtration system in fluid communication with the steam output and including a membrane filter with a permeate side and an opposing retentate side. The membrane filter includes a separation membrane constructed to reject organic molecules. The system may be used for removing organic compounds, such as anti-corrosion agents or contaminants, from steam.

The invention relates to a method for obtaining natural gas components, wherein, using natural gas, a feed mixture containing methane and helium is provided and subjected to a separating sequence so as to obtain a natural gas product which is enriched with methane and depleted of helium in comparison to the feed mixture and a helium product which is depleted of methane and enriched with helium in comparison to the feed mixture, which method comprises one or more membrane separating steps and one or more pressure change adsorption steps. According to the invention, the feed mixture is provided using natural gas containing methane, higher hydrocarbons, helium and carbon dioxide, and the providing of the feed mixture comprises depleting the natural gas used for provision of the feed mixture of carbon dioxide and of the higher hydrocarbons. The present invention also relates to a corresponding system.

A method and device for purifying heptafluoroisobutyronitrile and a dilution gas from a used gas mixture comprising heptafluoroisobutyronitrile, a dilution gas and arcing by-products. The method comprising the steps of (a) contacting the used gas mixture with at least one adsorbent material to generate a gas stream depleted in arcing by-products; (b) contacting the gas stream depleted in by-products with a first membrane to obtain a first permeate stream rich in the dilution gas, and a first retentate stream rich in heptafluoroisobutyronitrile; (c) contacting the first permeate stream rich in the dilution gas with a second membrane to obtain a second permeate stream rich in the dilution gas and a second retentate stream rich in heptafluoroisobutyronitrile; and (d) combining the first and second retentate streams rich in heptafluoroisobutyronitrile.

An acidic gas separation device includes: a first separation device which has an inorganic separation membrane and is configured to separate a gaseous hydrocarbon fluid containing an acidic gas into a first gaseous fluid having a large acidic gas content and a second gaseous fluid having a smaller acidic gas content than the first gaseous fluid by the inorganic separation membrane; and a second separation device which has an organic polymer separation membrane and is configured to separate the second gaseous fluid into a third gaseous fluid having a large acidic gas content and a fourth gaseous fluid having a smaller acidic gas content than the third gaseous fluid by the organic polymer separation membrane.

A process for sweetening a syngas stream, the process comprising the steps of: providing a syngas stream to a nonselective amine absorption unit, the sour syngas stream comprising syngas, carbon dioxide, and hydrogen sulfide; separating the syngas stream in the nonselective amine absorption unit to obtain an overhead syngas stream and an acid gas stream; introducing the acid gas stream to a membrane separation unit, the acid gas stream comprising hydrogen sulfide and carbon dioxide; separating the acid gas stream in the membrane separation unit to produce a retentate stream and a permeate stream, wherein the retentate stream comprises hydrogen sulfide, wherein the permeate stream comprises carbon dioxide; introducing the retentate stream to a sulfur recovery unit; processing the retentate stream in the sulfur recovery unit to produce a sulfur stream and a tail gas stream, wherein the sulfur stream comprises liquid sulfur.

A process for recovering sulfur from a sour gas is provided. The process includes the steps of: providing the sour gas to a membrane separation unit having a carbon dioxide-selective membrane that comprises a perfluoropolymer, wherein the sour gas comprises carbon dioxide and at least 1 mol % hydrogen sulfide; separating the sour gas using the carbon dioxide-selective membrane in the membrane separation stage to obtain hydrogen sulfide-enriched gas and hydrogen sulfide-stripped gas, wherein the hydrogen sulfide-enriched gas has a hydrogen sulfide concentration of at least 20 mol %, and wherein the hydrogen sulfide-stripped gas comprises carbon dioxide; and processing the hydrogen sulfide-enriched gas in a sulfur recovery unit to obtain sulfur.

Process and plant for membrane permeation treatment of a carbon dioxide and methane-containing biogas stream in which the biogas stream is compressed with a compressor and the compressed biogas stream is fed to a membrane separation unit comprising first and second modules each containing at least one membrane selective for carbon dioxide over methane. The first module separates the compressed biogas stream into a first, second, and third methane-deficient permeates (in comparison to the biogas stream) and a first methane-enriched retentate (in comparison to the biogas stream). The first permeate being richer in methane than the second or third permeates. The second module separates the first permeate into a fourth methane-deficient permeate and a second methane-enriched retentate. The second and third retentates are recycled back to an inlet of the compressor.

A process and system to control the final product quality in a system for separating olefins and paraffins in a membrane system. A small finishing membrane stage is added to an existing membrane system that takes a slip stream from the product, purifies it to a very high concentration of propylene and blends it back into the product stream.

An apparatus is provided for the production of biomass or a bioproduct, the apparatus comprising: at least one elongate bioreactor, the bioreactor comprised of at least one outer membrane layer that defines a substantially tubular compartment that is capable of being filled with a liquid or gel, wherein the membrane layer is comprised of a material that is permeable to gas transfer across the membrane layer. A chamber is provided comprising walls that define and enclose a gaseous atmosphere within. At least a part of the bioreactor is located inside the chamber. A control system controls the composition of the atmosphere within the chamber and gas transfer occurs across the membrane layer of the bioreactor between the tubular compartment and the atmosphere comprised within the chamber. Methods of using the apparatus in order to manufacture biomass are also provided.

A method for treating a natural gas containing carbon dioxide using membrane modules which are assigned to a first treatment stage or a second treatment stage and are fluidically connected to a retentate mode or a permeate mode. When evolution in the operating conditions results in one of the processing levels requiring less membrane surface for gas processing and the other processing level requiring more membrane surface for gas processing, then the method allows for reassignment of needed membrane modules assigned from one processing level requiring less membrane surface to another processing level requiring more membrane surface.