Described herein are methods of manufacturing an at-shore water-based apparatus for liquefaction of natural gas. In some cases, the methods can include determining a weight of an air-cooled electrically driven refrigeration system (AER System); locating a ballast medium in a hull where the ballast medium has a simulated weight approximate to the weight of the AER System; determining a deflection of the hull caused by the simulated weight; moving the ballast medium off the hull while attaching the AER System; assembling a plurality of liquefied natural gas (LNG) storage tanks in the hull; and coupling the AER System with the LNG storage tanks. The ballast medium can be moved off the hull such that the weight of the ballast medium supported by the hull is reduced in order to maintain the deflection of the hull while the AER System is attached.

Apparatus, systems, and methods store energy by liquefying a gas such as air, for example, and then recover the energy by regasifying the cryogenic liquid and combusting or otherwise reacting the gas with a fuel to drive a heat engine. Carbon may be captured from the heat engine exhaust by using the cryogenic liquid to freeze carbon dioxide out of the exhaust. The process of liquefying the gas may be powered with electric power from the grid, for example, and the heat engine may be used to generate electricity. Hence, in effect these apparatus, systems, and methods may provide for storing electric power from the grid and then subsequently delivering it back to the grid.

A method for capturing carbon dioxide from a flue gas includes (i) removing moisture from a flue gas to yield a dried flue gas; (ii) compressing the dried flue gas to yield a compressed gas stream; (iii) reducing the temperature of the compressed gas stream to a temperature T.sub.1 using a first heat exchanger; (iv) reducing the temperature of the compressed gas stream to a second temperarature T.sub.2 using a second heat exchanger stream, where T.sub.2<T.sub.1 and at least a portion of the carbon dioxide from the compressed gas stream condenses, thereby yielding a solid or liquid condensed-phase carbon dioxide component and a light-gas component; (v) separating purities the condensed-phase component from the light-gas component to produce a condensed-phase stream and a light-gas stream; and (vi) using at least a portion of the condensed-phase stream and/or the light-gas stream in the second heat exchanger.

A method of controlling the renewable energy absorbed by a hybrid power train for driving a load, and in particular compressors for a liquefied natural gas (LNG) plant is disclosed. The method comprises an analysis of the health status of part and of the whole hybrid power plant that drive the load. A power plant is also disclosed, operated by the controlling method.

Described herein are systems related to at-shore liquefaction of natural gas. In some cases, the system for liquefaction of natural gas can include a land-based source of electricity; a land-based source of feed gas; an at-shore water-based apparatus moored to an at-shore location, and a transit bridge extending between the water-based apparatus and land upon which the land-based source of electricity and the land-based source of feed gas are located. The at-shore water-based apparatuses can include a hull, an air-cooled electrically-driven refrigeration system (AER System), and a plurality of liquefied natural gas (LNG) storage tanks that are on a lower deck of the hull. The transit bridge can support at least one of a first line for transmitting electricity from the land-based source of electricity to the water-based apparatus and a second line for carrying feed gas from the land-based source of feed gas to the water-based apparatus.

A photoelectric hydrogen production energy storage and cold energy recovery coupled dry ice production device and a use method are disclosed. The device comprises a photoelectric conversion liquid hydrogen energy storage unit, photoelectricity participates in electrolysis of water in the storage unit to prepare hydrogen, and surplus hydrogen meeting downstream process requirements is liquefied in the unit; liquid hydrogen is output, so that intermittent photoelectric energy is converted into hydrogen energy to be stored. When hydrogen production through electrolysis of water is insufficient but industrial hydrogen is continuously used, high-grade and low-grade cold energy of low-temperature liquid hydrogen serving as cold sources in the unit is recovered from industrial tail gas purified CO.sub.2 and air separation nitrogen, liquid nitrogen and liquid CO.sub.2 are output and used for the storage unit and dry ice production respectively, and the liquid hydrogen is reheated and supplied to a downstream process.

A nitrogen generating method for producing product nitrogen using a nitrogen generating device comprising a main heat exchanger for cooling feed air, a nitrogen rectification column into which the feed air cooled in the main heat exchanger is introduced, and a nitrogen condenser which condenses a vapour stream fed from the nitrogen rectification column and circulates the same to the nitrogen rectification column, the method including a control step for discharging liquid nitrogen condensed by the nitrogen condenser and stored in a liquid nitrogen buffer, which is provided in an upper gas phase portion of the nitrogen rectification column or separately from the nitrogen rectification column, to a rectification portion of the nitrogen rectification column in response to an increase in an amount of product nitrogen or an increase in a flow rate of the feed air.

An apparatus and process for pre-liquefaction processing of a fluid (e.g. hydrogen) can permit a reduction in capital costs and also an improvement in operational efficiency in flexibility. Embodiments can be configured to account for large variations in feed to be provided for liquefaction and also permit capital cost reductions associated with pre-liquefaction processing so the overall capital cost for liquefaction can be greatly reduced while also providing improved operational flexibility. For instance, embodiments can be configured to utilize one or more common pre-liquefaction processing elements to treat a fluid for pre-cooling of a fluid to a pre-selected liquefaction feed temperature.

An apparatus and process for processing of a fluid (e.g. hydrogen) for liquefaction can permit a reduction in power consumption and also an improvement in operational efficiency in flexibility. Embodiments can be configured to account for large variations in feed to be provided for liquefaction and also permit operational cost reductions associated with liquefaction processing so the overall power consumption and operational cost for liquefaction can be greatly reduced while also providing improved operational flexibility. For instance, embodiments can be configured to feed a fluid to multiple liquefiers of a train of liquefiers based on a pre-selected set of feed routing criteria for improving power consumption and providing greater operational flexibility for liquefaction operations.

Described herein are apparatuses and systems related to at-shore liquefaction of natural gas. The at-shore water-based apparatuses can include a hull, an air-cooled electrically-driven refrigeration system (AER System), and a plurality of liquefied natural gas (LNG) storage tanks that are on a lower deck of the hull. The AER System can be supported by a plurality of support structures extending through an upper deck of the hull.