Integrated plants and associated processes for producing ammonia and sulfuric acid have been developed comprising air separation and water electrolysis subsystems and which make surprisingly efficient use of the products from these subsystems (i.e. oxygen and nitrogen from the former and hydrogen and oxygen from the latter). The invention is particularly suitable for use as part of an integrated fertilizer production plant.

A system and method for co-producing ultra-high purity oxygen and ultra-high purity hydrogen from a water electrolysis unit is provided. The presently disclosed system and method includes upgrading the crude oxygen stream coming from the water electrolysis unit by means of a small, stand-alone cryogenic distillation system wherein the refrigeration for such cryogenic distillation system is supplied by a nitrogen recycle refrigeration loop.

A process comprising: subjecting a process gas containing NOx to a stage for absorption of NOx in a suitable absorption means, obtaining nitric acid and a tail gas containing nitrogen, argon and residual NOx; subjecting said tail gas to a treatment which comprises at least one NOx removal stage, obtaining a conditioned tail gas; subjecting at least a portion of said conditioned tail gas to a separation treatment, obtaining a product stream containing argon and a product stream containing nitrogen.

A system used to recycle exhaust gas during olefin polymer production, comprising: a compression cooling mechanism (101); a hydrocarbon membrane separation mechanism (102) and a hydrogen membrane separation mechanism (103), both connected to a first outlet (202) of the compression cooling mechanism; and a deep cooling mechanism (104) connected to a first outlet (208) of the hydrogen membrane separation mechanism. A method used to recycle exhaust gas during olefin polymer production, comprising a compression cooling step, a hydrocarbon membrane separation step, a hydrogen membrane separation step and a deep cooling step.

A process comprising: subjecting a process gas containing NOx to a stage for absorption of NOx in a suitable absorption means, obtaining nitric acid and a tail gas containing nitrogen, argon and residual NOx; subjecting said tail gas to a treatment which comprises at least one NOx removal stage, obtaining a conditioned tail gas; subjecting at least a portion of said conditioned tail gas to a separation treatment, obtaining a product stream containing argon and a product stream containing nitrogen.

In general, the present invention is directed to processes for separating a vapor comprising a first component and a second component using high-pressure density-driven separation. The present invention further relates to various processes for the capture of carbon dioxide. In particular, various processes of the present invention relate to the separation of carbon dioxide from flue gas of combustion processes. The invention also applies to upgrading fuel gases containing carbon dioxide. The invention also applies to separation of hydrogen from fuel gas vapor solutions.

A system used to recycle exhaust gas during olefin polymer production, comprising: a compression cooling mechanism (101); a hydrocarbon membrane separation mechanism (102) and a hydrogen membrane separation mechanism (103), both connected to a first outlet (202) of the compression cooling mechanism; and a deep cooling mechanism (104) connected to a first outlet (208) of the hydrogen membrane separation mechanism. A method used to recycle exhaust gas during olefin polymer production, comprising a compression cooling step, a hydrocarbon membrane separation step, a hydrogen membrane separation step and a deep cooling step.

An apparatus for the production of air gases by the cryogenic separation of air can include a cold box having a heat exchanger, and a system of columns; a pressure monitoring device; and a controller. The cold box can be configured to receive a purified and compressed air stream under conditions effective for cryogenically separating the air stream to form an air gas product. The apparatus may also include means for transferring the air gas product from the cold box to an air gas pipeline. The pressure monitoring device is configured to monitor the pipeline pressure, and the controller is configured to determine whether to operate in a power savings mode or a variable liquid production mode. By operating the apparatus in a dynamic fashion, a power savings and/or additional high value cryogenic liquids can be realized in instances in which the pipeline pressure deviates from its highest value.

A plant for producing an argon-rich stream from a mixture formed by a purge fluid from a plant for producing ammonia comprises at least two methane scrubbing columns upstream of a methane separation column and, downstream therefrom, a nitrogen/argon separation column.

A method of producing .sup.13N-ammonia for use in medical imaging is provided, which includes irradiating .sup.14N (having a natural abundance of 99.64%) with a collimated bremsstrahlung radiation (gamma-ray beam) obtained by directing high-energy electrons onto a high-Z converter. The .sup.14N to be irradiated may be in the form of liquid ammonia (.sup.14NH.sub.3) or ammonia gas to directly produce .sup.13N-ammonia (.sup.13NH.sub.3) or in the form of liquid nitrogen to indirectly produce .sup.13N-ammonia through conversion of the irradiated liquid nitrogen (N.sub.2) via known conversion processes to .sup.13N-ammonia. The photons have an energy level above the threshold of the .sup.14N(,n).sup.13N reaction (about 10.5 MeV).