Proposed is a process for producing ethylene wherein using a dehydrogenation of ethane a process gas containing at least ethane, ethylene and compounds having a lower boiling point than ethane and ethylene is formed, wherein using at least a part of the process gas a separation input is formed and subjected to a low-temperature separation (6) in which the separation input is cooled and in which one or more condensates are separated from the separation input, wherein the condensate(s) are at least partly subjected to a low-temperature rectification to obtain a gaseous first fraction and a liquid second fraction, wherein the gaseous first fraction contains at least the ethane and the ethylene in a lower proportion than in the separation input and the compounds having a lower boiling point than ethane and ethylene in a higher proportion than in the separation input. It is provided that the first fraction is at least partly subjected to a pressure swing adsorption (7) by means of which a third fraction containing predominantly or exclusively ethylene and ethane and a fourth fraction containing predominantly or exclusively methane and carbon monoxide are formed. A corresponding plant (100) likewise forms part of the subject matter of the present invention.

The present invention relates generally to an attrition resistant core-in-shell composite adsorbent comprising at least a zeolite-containing CO.sub.2 removal adsorbent and a binder on an inert dense core. The attrition resistant core-in-shell composite adsorbent has an attrition loss of less than about 2 wt %. The core-in-shell composite adsorbent is preferably used in a multi-layered adsorption system in a cyclic adsorption process, preferably used in a PSA prepurification process prior to cryogenic air separation.

The method for producing liquid hydrogen can include the steps of: introducing pressurized natural gas from a high pressure natural gas pipeline to a gas processing unit under conditions effective for producing a purified hydrogen stream; and introducing the purified hydrogen stream to a hydrogen liquefaction unit under conditions effective to produce a liquid hydrogen stream, wherein the hydrogen liquefaction unit provides a warm temperature cooling and a cold temperature cooling to the purified hydrogen stream, wherein the warm temperature cooling is provided by utilizing letdown energy of a pressurized stream selected from the group consisting of a nitrogen stream sourced from a nitrogen pipeline, a natural gas stream sourced from the high pressure natural gas pipeline, an air gas sourced from an air separation unit, and combinations thereof, wherein the cold temperature is provided by utilizing letdown energy of the purified hydrogen stream.

A helium-containing stream is recovered from a natural gas feed using a membrane followed by multiple distillation steps. Refrigeration is provided by expanding a bottoms liquid with a higher nitrogen content than the feed, achieving a lower temperature in the process. The helium-enriched vapor is then purified and the helium-containing waste stream is recycled to maximize recovery and reduce the number of compressors needed. The helium-depleted natural gas stream can be returned at pressure for utilization or transportation.

A liquid air energy storage system comprises an air liquefier, a storage facility for storing the liquefied air, and a power recovery unit coupled to the storage facility. The air liquefier comprises an air input, an adsorption air purification unit for purifying the input air, and a cold box for liquefying the purified air. The power recovery unit comprises a pump for pressurising the liquefied air from the liquid air storage facility, an evaporator for transforming the high-pressure liquefied air into high-pressure gaseous air, an expansion turbine capable of being driven by the high-pressure gaseous air, a generator for generating electricity from the expansion turbine, and an exhaust for exhausting low-pressure gaseous air from the expansion turbine. The exhaust is coupled to the adsorption air purification unit such that at least a portion of the exhausted low-pressure gaseous air is usable to regenerate the adsorption air purification unit.

A data center is cooled by a cryogenic cooling system which is wind driven, and powered by energy stored in the cryogenic liquid. The cooling occurs through downwardly passing cryogenic liquid which is recycled and pushed back to a top of a system in a cyclic manner.

The present invention provides strategies to integrate adsorption and liquefaction techniques to separate hydrocarbon feed mixtures into purified light and heavy components, respectively. Initially, the hydrocarbon stream is separated into a light and heavy stream. The light stream can be integrated into a natural gas product. The heavy stream is partially liquefied. A first gas liquid separation of the partially liquefied heavy stream at an elevated pressure separates the liquid heavy stream from a methane-containing gas. The rejected methane component, which generally will include some rejected C2 and C3+ material, can be recycled to be combined with the feed mixture for re-processing. A further aspect of the strategy is then to practice at least one additional gas-liquid separation of the separated liquid heavy stream at a lower pressure effective to help further resolve the liquid heavy stream from C2-containing gas. The rejected C2 component, which generally will include some rejected C1 and C3+ material, can then be recycled back into the feed mixture for reprocessing or used as all or a portion of a light hydrocarbon product.

Provided are apparatus and systems for performing a swing adsorption process. This swing adsorption process may involve performing a startup mode process prior to beginning a normal operation mode process to remove contaminants from a gaseous feed stream. The startup mode process may be utilized for swing adsorption processes, such as TSA and/or PSA, which are utilized to remove one or more contaminants from a gaseous feed stream.

A process for removing CO.sub.2 from a methane-containing gas, having the steps of providing a methane-containing gas containing at least CO.sub.2 as an impurity, cooling the gas to remove CO.sub.2 from the methane-containing gas by freezing out same, and additionally reducing the CO.sub.2 concentration of the gas using a pressure temperature swing adsorption apparatus (PTSA), whereby a methane-enriched product gas is obtained. At least a part of the product gas is then used as treatment gas and is passed through the PTSA for treatment of the PTSA, whereby CO.sub.2 is absorbed by the treatment gas and is removed from the PTSA as a CO.sub.2-enriched treatment gas. The treatment gas is then recycled and admixed with the methane containing gas.

Process and apparatus for producing helium, neon, or argon product gas using an adsorption separation unit having minimal dead end volumes. A second separation unit receives a stream enriched in helium, neon, or argon, and a stream is recycled from the second separation unit back to the adsorption separation unit in a controlled manner to maintain the concentration of the helium, neon, or argon in the feed to the separation unit within a targeted range.