The present disclosure relates to the technical field of natural gas power generation, and particularly discloses a natural gas combined power generation process with zero carbon emission, the process comprising: introducing the pressurized air into an air separation facility to obtain liquid oxygen and liquid nitrogen, wherein the liquid oxygen is used for gasification and power generation, the liquid nitrogen is applied as the coolant of flue gas, and then used for the gasification and power generation; the liquid nitrogen and a part of liquid oxygen stored during the valley period with low electricity load are provided for use during the peak period with high electricity load; the natural gas, oxygen and the recyclable CO.sub.2 jointly enter a combustion gas turbine for burning to drive an air compressor and a generator to rotate at a high speed, the air compressor compresses the air to a pressure of 0.40.8 MPa, the generator generates electricity; the high-temperature combustion flue gas performs the supercritical CO.sub.2 power generation, its coolant is liquid oxygen; the moderate temperature flue gas then exchanges heat with liquid nitrogen, the liquid nitrogen vaporizes for power generation, the cooled flue gas is dehydrated and subjects to distillation and separation to obtain the recovered CO.sub.2, a part of the CO.sub.2 can be returned for circulation and temperature control, another part of the CO.sub.2 may be used for replenishment of work medium for supercritical CO.sub.2 power generation, and the remaining part of CO.sub.2 may be sold outward as liquid CO.sub.2 product. During the peak period with high electricity load, the liquid nitrogen stored during the valley period with low electricity load and separated during the peak period is pumped and pressurized and then subjects to heat exchange and vaporization for power generation. The power generation process provided by the present disclosure not only solves the difficult problems in the existing natural gas combined power generation technology such as high water consumption, low power generation efficiency and small range of peak load adjustment capacity; but also can compress air with high unit volume for energy storage with a high conversion efficiency, and greatly reduce load of the air compressor, thereby perform CO.sub.2 capture and utilization with low cost, zero NO.sub.x emission and discharging fuel gas at a normal temperature, and significantly improve the power generation efficiency.

A process for regenerating catalyst from a fluidized catalytic process comprising is disclosed. The process comprises providing an oxygen stream and a preheated carbon dioxide recycle stream and mixing the oxygen stream and the preheated carbon dioxide recycle stream to provide a carbon dioxide rich oxidation stream. The carbon dioxide rich oxidation stream is passed to a regenerator unit to provide a carbon dioxide rich flue gas stream. One or more of a sulfur-containing compound, a nitrogen-containing compound, or both in the carbon dioxide rich flue gas stream is reacted with a reactant in a decontamination reactor to form a reactor effluent stream comprising reactant salt. The reactor effluent stream is filtered to remove the reactant salt and catalyst fines to produce a filtered reactor effluent stream. A carbon dioxide recycle stream is taken from the filtered reactor effluent stream.

Liquid hydrogen is produced while reducing emission of carbon dioxide to the atmosphere. Provided is a liquid hydrogen production device including: a carbon dioxide cycle plant (2), which includes a turbine (23) using a carbon dioxide fluid as a driving fluid, and is configured to drive the turbine (23) to generate motive power with use of a carbon dioxide cycle in which the carbon dioxide fluid discharged from the turbine (23) is increased in pressure and heated and is then re-supplied to the turbine (23); and a liquefaction plant (4) configured to cool gaseous hydrogen by heat exchange with a refrigerant, to obtain liquid hydrogen. The motive power generated by driving of the turbine (23) is used as motive power to be consumed in the liquefaction plant (4).

A system for storing or producing electricity, which allows stabilization of a power network under conditions of excess availability of electricity or lack thereof and for producing liquefied natural gas is provided.

Combined cycle natural gas processing system that does not discharge carbon dioxide to the atmosphere. The system is provided with an acid gas removal unit that separates carbon dioxide contained in natural gas, and includes a natural gas processing plant that produces liquefied natural gas, and a carbon dioxide cycle. High energy held by a high-temperature and high-pressure carbon dioxide fluid of the carbon dioxide cycle is converted into electrical energy or mechanical energy and supplied to a power consumption device and an energy consumption device provided in the natural gas processing plant. The carbon dioxide fluid extracted from the carbon dioxide cycle and a carbon dioxide separation stream separated by the acid gas removal unit are supplied to a carbon dioxide reception facility capable of receiving carbon dioxide, so that the carbon dioxide generated with production of the liquefied natural gas is not released to the atmosphere.

The present disclosure relates to systems and methods useful for power production. In particular, a power production cycle utilizing CO.sub.2 as a working fluid may be configured for simultaneous hydrogen production. Beneficially, substantially all carbon arising from combustion in power production and hydrogen production is captured in the form of carbon dioxide. Further, produced hydrogen (optionally mixed with nitrogen received from an air separation unit) can be input as fuel in a gas turbine combined cycle unit for additional power production therein without any atmospheric CO.sub.2 discharge.

The present disclosure relates to systems and methods useful for power production. In particular, a power production cycle utilizing CO.sub.2 as a working fluid may be combined with a second cycle wherein a compressed CO.sub.2 stream from the power production cycle can be heated and expanded to produce additional power and to provide additional heating to the power production cycle.

The present disclosure relates to systems and methods useful for power production. In particular, a power production cycle utilizing CO.sub.2 as a working fluid may be configured for simultaneous hydrogen production. Beneficially, substantially all carbon arising from combustion in power production and hydrogen production is captured in the form of carbon dioxide. Further, produced hydrogen (optionally mixed with nitrogen received from an air separation unit) can be input as fuel in a gas turbine combined cycle unit for additional power production therein without any atmospheric CO.sub.2 discharge.

A cryogenic cooling system for an aircraft includes a first air cycle machine, a second air cycle machine, and a means for collecting liquid air. The first air cycle machine is operable to output a cooling air stream based on a first air source. The second air cycle machine is operable to output a chilled air stream at a cryogenic temperature based on a second air source cooled by the cooling air stream of the first air cycle machine. An output of the second air cycle machine is provided to the means for collecting liquid air.

A system for an aircraft includes an engine bleed source of a gas turbine engine. The system also includes a means for chilling an engine bleed air flow from the engine bleed source to produce a chilled working fluid. The system further includes a means for providing the chilled working fluid for an aircraft use.