A system and method for producing two or more nitrogen product streams and a crude argon stream from a nitrogen and argon producing air separation unit is provided. The disclosed embodiments of the cryogenic-based nitrogen and argon producing air separation units and associated air separation cycles include the means for directing a first portion of a boil-off stream from an argon condenser of the air separation unit to a waste expansion refrigeration circuit and concurrently recycling a second portion of the boil-off stream from the argon condenser to the main air compression system of the air separation unit to be mixed or blended with the incoming feed air. Optionally, a third portion of the boil-off stream from the argon condenser may be further compressed in a cold compressor and returned to the lower pressure column.

An apparatus for the production of air gases with variable liquid production 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 adjust the product pressure of the air gas product coming out of the cold box based upon the pipeline pressure and to further adjust liquid production from the cold box based on the adjusted product pressure.

A full liquid-product air separation equipment is disclosed. The equipment comprises an air filtration system, a compression system, a precooling system, a purification system, a high-temperature expander having a first pressurizing part and a first expanding part, a low-temperature expander having a second pressurizing part and a second expanding part, a main heat exchanger having a first heat exchange pipeline, a second heat exchange pipeline, a third heat exchange pipeline, a fourth heat exchange pipeline and a fifth heat exchange pipeline, and a rectification system for rectifying air. The equipment has a simple configuration, is easy to implement, and has high gas separation efficiency and low energy consumption.

A process for the production of a liquid oxygen stream and a liquid hydrocarbon-rich stream by the cryogenic rectification of an inlet air stream, including dividing the inlet air stream into a first portion, and a second portion. Cooling the first portion, and the second portion against a cooled multicomponent refrigerant circuit, thereby producing a first cooled portion, and a second cooled portion. Condensing the first cooled portion, thereby producing a condensed first portion, then introducing the condensed first portion into one or more distillation columns. Expanding the second cooled portion in a turbo-expander, thereby producing an expanded second portion, then introducing the expanded second portion within the one or more distillation columns. Producing within the one or more distillation columns at least a waste nitrogen stream, a nitrogen enriched stream, and an oxygen enriched stream.

A process for the production of a liquid oxygen stream by the cryogenic rectification of an inlet air stream, including dividing the inlet air stream into a first portion, and a second portion. Cooling the first portion, and the second portion against a cooled multicomponent refrigerant circuit, thereby producing a first cooled portion, and a second cooled portion. Condensing the first cooled portion, thereby producing a condensed first portion, then introducing the condensed first portion into one or more distillation columns. Expanding the second cooled portion in a turbo-expander, thereby producing an expanded second portion, then introducing the expanded second portion within the one or more distillation columns. Producing within the one or more distillation columns at least a waste nitrogen stream, a nitrogen enriched stream, and an oxygen enriched stream. Withdrawing the oxygen enriched stream from the one or more distillation columns as a liquid oxygen stream.

A cryogenic air separation apparatus comprises: a heat exchanger, a first rectification column, a first condenser, a second rectification column, a third rectification column, a second condenser, a high-purity oxygen rectification column, a third condenser, a nitrogen compressor, and a compressed recycled gas line L52 for introducing product nitrogen gas compressed by the first nitrogen compressor into a warm end (heat source) of an ultra-high-purity oxygen vaporizer as a compressed recycled gas.

Embodiments of the present invention relates to two improved catalysts and associated processes that directly converts carbon dioxide and hydrogen to liquid fuels. The catalytic converter is comprised of two catalysts in series that are operated at the same pressures to directly produce synthetic liquid fuels or synthetic natural gas. The carbon conversion efficiency for CO.sub.2 to liquid fuels is greater than 45%. The fuel is distilled into a premium diesel fuels (approximately 70 volume %) and naphtha (approximately 30 volume %) which are used directly as “drop-in” fuels without requiring any further processing. Any light hydrocarbons that are present with the carbon dioxide are also converted directly to fuels. This process is directly applicable to the conversion of CO.sub.2 collected from ethanol plants, cement plants, power plants, biogas, carbon dioxide/hydrocarbon mixtures from secondary oil recovery, and other carbon dioxide/hydrocarbon streams. The catalyst system is durable, efficient and maintains a relatively constant level of fuel productivity over long periods of time without requiring re-activation or replacement.

The present disclosure provides an energy-efficient process for preparing nitrogen and oxygen for a glass melting furnace. A device required by the process includes a filter, a turbine air compressor, an air pre-cooling unit, alternately used molecular sieve adsorbers, an electric heater, a main heat exchanger, a rectifying tower I, a main condenser-evaporator I, a rectifying tower II, a main condenser-evaporator II, a rectifying tower III, a main condenser-evaporator III, a supercooler, an expander I and an expander II. The three rectifying towers are used to prepare a low-pressure nitrogen product and an oxygen product with a certain pressure at the same time. The oxygen product with a certain pressure is used for oxygen-enriched combustion for the glass melting furnace, and the low-pressure nitrogen product is used as shielding gas of a tin bath.

The present disclosure provides a method for cryogenic air separation. In the method, part (b2) of the air (b) is compressed in warm booster (7), cooled in heat exchanger (2) and then divided in two, one part (c1) being compressed in a cold booster(9) driven by one turboexpander (11) in which the other part (c2) of air (c) is expanded, and another part of the feed air is not boosted but is expanded in another turboexpander (6) which drives the warm booster (7). The present disclosure also provides an apparatus for cryogenic air separation.

A process for producing liquid oxygen, including, a first operating mode, and a second operating mode. During the first operating mode, the distillation column produces a first flowrate of product liquid oxygen, and a first flow rate of liquid nitrogen product. During the second operating mode, the distillation column produces a second flowrate of product liquid oxygen, and a second flow rate of liquid nitrogen product. Wherein, the second flowrate of product liquid oxygen is greater than the first flowrate of product liquid oxygen.