A liquid air energy storage system comprises an air liquefier, a liquid air storage facility for storing the liquefied air, and a power recovery unit coupled to the liquid air 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 comprise a pump for pressurizing 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 low-pressure gaseous air exhausted from the expansion turbine is usable to regenerate the adsorption air purification unit.

A method includes compressing an air flow to a first pressure, transferring heat from the air flow to a liquefaction fluid via an intercooler heat exchanger, compressing the air flow to a second pressure greater than the first pressure, combusting the air flow and a fuel to generate a combustion product flow, and driving a turbine with the combustion product flow. The turbine is configured to drive machinery of a liquefaction system. The liquefaction fluid includes at least one of a pre-cooling fluid, a refrigerant, and a liquefied product of the liquefaction system.

The invention relates to a method for storing and recovering energy, according to which a condensed air product (LAIR) is formed in an energy storage period, and in an energy recovery period, a pressure flow is formed and is expanded to produce energy using at least part of the condensed air product (LAIR) without a supply of heat from an external heat source. The method comprises inter alia, for the formation of the condensed air product (LAIR): the compression of air (AIR) in an air conditioning unit (10), at least by means of an adiabatically operated compressor device (12); the formation of a first and a second sub-flow downstream of the adiabatically driven compressor device (12), said flows being formed from the air (AIR) that has been compressed in said device and the guiding of the first and second sub-flows in parallel through a first thermal store (131) and through a second thermal store (132), in which stores heat produced during the compression of the air (AIR) is at least partially stored. For the formation of the pressure flow, a vaporized product (HPAIR) is produced inter alia from at least one part of the condensed air product (LAIR). During the energy-producing expansion process, the pressure flow is guided through a first expansion device (61) and a second expansion device (62) and is thus expanded in each device. Heat stored in the first heat store device (131) is transferred to the pressure flow upstream of the first expansion device (61) and heat stored in the second heat store device (132) is transferred to the pressure flow upstream of the second expansion device (62). The invention also relates to an installation (100).

A method for converting carbon dioxide gas to liquefied carbon dioxide includes (a) receiving, in a heat exchanger, a carbon dioxide gas stream and a liquefied natural gas stream, and (b) exposing the carbon dioxide gas stream to the liquefied natural gas stream to convert the carbon dioxide gas stream to liquefied carbon dioxide, and the liquefied natural gas stream is regasified to natural gas. The natural gas exits the heat exchanger and is sent to a steam methane reformer for further processing.

A method for energy storage and recovery is based on the liquid air energy storage (LAES) operated at the pressure relationship such that the pressure of discharge air is greater than the charge air to provide a high round-trip efficiency. External cold source and cold thermal energy storage are used in a LAES to achieve a decrease in the LAES capital costs. A demand for a supplemental cold energy provided by external sources may be minimized. These features alone or in combination may result in reduced power demand required for cooling.

A system and method for separating air in an air separation plant is provided. The disclosed systems and methods divert a portion of the compressed, purified air stream to a bypass system configured to selectively produce a higher pressure compressed output stream or a lower pressure compressed output stream. The higher pressure and/or lower pressure compressed output streams are cooled in a main heat exchanger by indirect heat transfer with a plurality of product streams from the air separation plant and then rectified in the distillation column system. A second portion of the compressed, purified air stream is partially cooled in the main heat exchanger and expanding in a turbo-expander to produce power and an exhaust stream which is directed to the distillation column system of the air separation plant where it imparts additional refrigeration generated by the expansion of the compressed air stream in the turbo-expander.

A method and device for generating electrical energy in a combined system of power plant, cold storage system and air compression system. The air compression system has a primary air compressor for generating a primary compressed air flow at a first pressure level. The power plant has a combustion unit which operates at a second pressure level and generates a combustion gas from which electrical energy is generated. The cold storage system has means for generating cold from compressed air, means for storing cold thus produced and means for generating a compressed air flow at the second pressure level using the stored cold. In a first operating mode (charging mode), a first compressed air flow is introduced from the air compression system into the cold storage system to charge the cold reservoir. In a second operating mode (discharging mode), the first compressed air flow generated in the primary air compressor, is introduced into the cold storage system to discharge the cold reservoir and to generate a third compressed air flow at the second pressure level, which is introduced into the combustion unit. The air compression system has a first booster for boosting compressed air compressed in the primary air compressor to the second pressure level. In a third operating mode (normal mode), the entire primary compressed air flow generated in the primary air compressor is boosted in the first booster to the second compressed air level and introduced into the combustion unit.

The invention relates to a method for storing and recovering energy, wherein an air liquefaction product (LAIR) is formed during an energy storage period, and a fluid pressure flow (12) is formed during an energy recovery period using at least one part of the air liquefaction product (LAIR) and is expanded for operation in at least one energy recovery device (14, 17). The air liquefaction product (LAIR) is obtained as a liquid medium during the energy storage period by compressing air in an air conditioning device (3), said compression being operated while supplying energy, in particular while supplying a current (9), optionally stored in a cold state, and fed to an evaporator unit (7). The air liquefaction product (LAIR) is expanded for operation as a fluid pressure flow (12) in the at least one energy recovery device (14, 17) during the energy recovery period after a pressure increase. The aim of the invention is to provide a solution with which even existing gas and steam power plants or open gas turbines are to be equipped with an energy storage capability. This is achieved in that the fluid pressure flow (12), in particular an air flow, is expanded in a first energy recovery device (14) and conducted through a recuperator device (13), in particular a heat boiler, upstream of said first energy recovery device (14), and thermal energy which has been decoupled from a flue gas flow (23) fed to the recuperator device (13) is coupled into the fluid pressure flow (12) in said heating tank. The flue gas flow (23) is fed to the recuperator device (13) from a fuel-fired second energy recovery device (17), in particular a gas turbine.

A system and method for cooling and liquefying a gas in a heat exchanger that includes compressing and cooling a mixed refrigerant using first and last compression and cooling cycles so that high pressure liquid and vapor streams are formed. The high pressure liquid and vapor streams are cooled in the heat exchanger and then expanded so that a primary refrigeration stream is provided in the heat exchanger. The mixed refrigerant is cooled and equilibrated between the first and last compression and cooling cycles so that a pre-cool liquid stream is formed and subcooled in the heat exchanger. The stream is then expanded and passed through the heat exchanger as a pre-cool refrigeration stream. A stream of gas is passed through the heat exchanger in countercurrent heat exchange with the primary refrigeration stream and the pre-cool refrigeration stream so that the gas is cooled. A resulting vapor stream from the primary refrigeration stream passage and a two-phase stream from the pre-cool refrigeration stream passage exit the warm end of the exchanger and are combined and undergo a simultaneous heat and mass transfer operation prior to the first compression and cooling cycle so that a reduced temperature vapor stream is provided to the first stage compressor so as to lower power consumption by the system. Additionally, the warm end of the cooling curve is nearly closed further reducing power consumption. Heavy components of the refrigerant are also kept out of the cold end of the process, reducing the possibility of refrigerant freezing, as well as facilitating a refrigerant management scheme.

A system and method for separating air in an air separation plant is provided. The disclosed systems and methods divert a portion of the compressed, purified air stream to a bypass system configured to selectively produce a higher pressure compressed output stream or a lower pressure compressed output stream. The higher pressure and/or lower pressure compressed output streams are cooled in a main heat exchanger by indirect heat transfer with a plurality of product streams from the air separation plant and then rectified in the distillation column system. A second portion of the compressed, purified air stream is partially cooled in the main heat exchanger and expanding in a turbo-expander to produce power and an exhaust stream which is directed to the distillation column system of the air separation plant where it imparts additional refrigeration generated by the expansion of the compressed air stream in the turbo-expander.