A method for operating the liquid air energy storage (LAES) includes production of the storable liquid air through consumption of a low-demand power and recovery the liquid air for co-production of an on-demand power and a high-grade saleable cold thermal energy which may be used, say, for liquefaction of the delivered natural gas; in so doing zero carbon footprint is provided both for fueled augmentation of the LAES power output and for LNG co-production at the LAES facility.

The present invention relates to a process and a system for supplying a backup gas at a higher pressure from a source gas at a lower pressure. The backup gas at the lower pressure is at least partially condensed against a backup liquid at a higher pressure in a reprocessing heat exchanger and as a result, the backup liquid is at least partially vaporized. The backup liquid at the higher pressure is formed from boosting liquefied backup gas at the lower pressure. A backup vaporizer is disposed downstream of the reprocessing heat exchanger to completely vaporize the backup liquid at a higher pressure before it was delivered to the customer. The present invention eliminates the use of costly gas compressor and mitigates associated safety risks, in particular when the backup gas is oxygen.

A novel concept for a high energy and material efficient nitric acid production process and system is provided, wherein the nitric acid production process and system, particularly integrated with an ammonia production process and system, is configured to recover a high amount of energy out of the ammonia that it is consuming, particularly in the form of electricity, while maintaining a high nitric acid recovery in the conversion of ammonia to nitric acid. The energy recovery and electricity generation process comprises pressurizing a liquid gas, such as air, oxygen and/or N.sub.2, subsequently evaporating and heating the pressurized liquid gas, particularly using low grade waste heat generated in the production of nitric acid and/or ammonia, and subsequently expanding the evaporated pressurized liquid gas over a turbine. In particular, the generated electricity is at least partially used to power an electrolyzer to generate the hydrogen needed for the production of ammonia. The novel concepts set out in the present application are particularly useful in the production of nitric acid based on renewable energy sources.

Liquefaction of industrial gases or gas mixtures (hydrocarbon and/or non-hydrocarbon) uses a modified aqua-ammonia absorption refrigeration system (ARP) to chill the gas or gas mixture during the liquefaction process. The gas is compressed to above its critical point, and the heat of compression energy may be recovered to provide some or all of the thermal energy required to drive the ARP. A Joule Thomson (JT) adiabatic expansion process results in no requirement for specialty cryogenic rotating equipment. The aqua-ammonia absorption refrigeration system includes a vapour absorber tower (VAT) that permits the recovery of some or all of the heat of solution and heat of condensation energy in the system when anhydrous ammonia vapour is absorbed into a subcooled lean aqua-ammonia solution. The modified ARP with VAT may operate at pressures as low as 10 kPa, and the ammonia gas chiller may operate at temperatures as low as −71° C.

Disclosed techniques include controlled liquefaction and energy management. A gas within a first pressure containment vessel is pressurized using a column of liquid. The gas that is being pressurized is cooled using a liquid spray, wherein the liquid spray is introduced into the first pressure containment vessel in a region occupied by the gas. The liquid spray keeps the pressurizing to be isothermal. The gas that was pressurized is metered into a second pressure containment vessel, wherein the metering enables liquefaction of the gas. The gas that was pressurized is stored in a gas capacitor prior to the metering. The gas that was liquefied in the second pressure containment vessel is pushed into a holding tank, wherein the holding tank stores a liquefied state of the gas, and wherein the pushing is accomplished by the pressure of the gas that was metered into the second pressure containment vessel.

A system which integrates a power production system and an energy storage system represented by gas liquefaction systems is provided.

A proposed method provides a fueled power output augmentation of the liquid air energy storage (LAES) with zero carbon emissions of its exhaust. It combines the production of liquid air using a low-demand power from the renewable or/and conventional energy sources and the recovery of stored air for production of on-demand power in the fueled supercharged reciprocating internal combustion engine (RICE) and associated expanders. An integration between the LAES and RICE makes possible to recover the RICE exhaust energy for increase in power produced by the expanders of LAES and to use a cold thermal energy of liquid air being re-gasified at the LAES facility for cryogenic capture of CO.sub.2 emissions from the RICE exhaust.

Certain embodiments of the present invention lies in providing a high-purity oxygen production system which is capable of supplying liquid nitrogen in order to supply the cold required by a high-purity oxygen production apparatus, without the use of a costly conventional liquefaction apparatus.

A high-purity oxygen production system in accordance with an embodiment can include: an air separation apparatus including a main heat exchanger, a medium-pressure column and a low-pressure column; and a high-purity oxygen production apparatus including a nitrogen compressor, a nitrogen heat exchanger and at least one (high-purity) oxygen rectification column, an oxygen-containing stream serving as a starting material for high-purity oxygen is supplied from the low-pressure column to the high-purity oxygen production apparatus, and liquid nitrogen obtained from the medium-pressure column is supplied to the high-purity oxygen production apparatus in order to replenish cold heat required for operation of the high-purity oxygen production apparatus.

A method and system for producing liquid air wherein liquid refrigerant is cycled between two core tanks maintained at a temperature sufficient to liquify compressed air passed through condensing tubing in the interior of the core tanks. Liquid refrigerant is cycled by alternating high pressure gas from a high pressure tank to one of the core tanks, which forces liquid refrigerant from this tank through an expansion device to expand a portion of the liquid refrigerant to absorb heat in the other core tank, the resulting refrigerant gas being driven into a low pressure tank. A compression device transfers the refrigerant gas from the low pressure tank to the high pressure tank and maintains the pressure in the high pressure tank. Connections between the low and high pressure tanks and the core tanks are reversed with each cycle.

A system that integrates a power production system and an energy storage system represented by gas liquefaction systems is provided.