The present disclosure relates to systems and methods that provide power generation using predominantly CO.sub.2 as a working fluid. In particular, the present disclosure provides for the use of a portion of the heat of compression from a CO.sub.2 compressor as the additive heating necessary to increase the overall efficiency of a power production system and method.

A method for liquefying ammonia can include the steps of: providing a pressurized carbon dioxide stream from a power generating facility; expanding the pressurized carbon dioxide stream to a lower pressure that is sufficient to produce a dual phase carbon dioxide fluid; introducing the dual phase carbon dioxide fluid to a gas-liquid separator; withdrawing a liquid stream from the gas-liquid separator; and liquefying an ammonia gas stream in an ammonia liquefier by indirect contact with the liquid stream from the gas-liquid separator, thereby forming a liquid ammonia stream and a gaseous carbon dioxide stream.

A polymerizable LC material comprising one or more reactive mesogenic compounds, one or more chiral compounds and a block copolymer that comprises at least one polyfluorooxetane block bonded to a polyether block, said polyfluorooxetane block having a repeating unit of the formula

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Further, a method for its preparation, a polymer film obtainable from a corresponding polymerizable LC material, a method of preparation of such polymer film, and the use of such polymer film and said polymerizable LC material in optical, electro-optical, decorative or security devices.

The present invention provides methods and system for power generation using a high efficiency combustor in combination with a CO.sub.2 circulating fluid. The methods and systems advantageously can make use of a low pressure ratio power turbine and an economizer heat exchanger in specific embodiments. Additional low grade heat from an external source can be used to provide part of an amount of heat needed for heating the recycle CO.sub.2 circulating fluid. Fuel derived CO.sub.2 can be captured and delivered at pipeline pressure. Other impurities can be captured.

The systems and methods described herein integrate a supercritical fluid power generation system with a LNG production/NGL separation system. A heat exchanger thermally couples the supercritical fluid power generation system with the LNG production/NGL separation system. A relatively cool heat transfer medium, such as carbon dioxide, passes through the heat exchanger and cools a first portion of extracted natural gas. The relatively warm heat transfer medium returns to the supercritical fluid power generation system where a compressor and a thermal input device, such as a combustor, are used to increase the pressure and temperature of the heat transfer medium above its critical point to provide a supercritical heat transfer medium. A second portion of the extracted natural gas may be used as fuel for the thermal input device.

A method of simultaneously liquefying CO2 and cooling natural gas, including providing a compressed CO2 loop, comprising a pressurized cooling stream, wherein a first compressed cooling stream and a second compressed cooling stream are produced by a CO2 compressor. Providing at least a portion of the first compressed cooling stream to a CO2 liquefaction system, wherein the first compressed cooling stream provides at least a portion of the refrigeration required by the CO2 liquefaction system. Providing at least a portion of the second compressed cooling stream to the pre-cooling system of a natural gas liquefaction system, wherein the second compressed cooling stream provides at least a portion of the refrigeration required by the natural gas pre-cooling.

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.

A carbon dioxide electrolytic device in an embodiment includes: an electrochemical reaction cell including: a first accommodation part that accommodates gas or a first electrolytic solution containing CO.sub.2; a second accommodation part that accommodates a second electrolytic solution containing H.sub.2O; a diaphragm provided between the first and second accommodation parts; a cathode that is in contact with the gas or the first electrolytic solution; and an anode that is in contact with the second electrolytic solution; a first supply part that supplies the gas or the first electrolytic solution to the first accommodation part; a second supply part that supplies the second electrolytic solution to the second accommodation part; and a carbon dioxide separation part that is connected to a discharge portion of a discharge containing O.sub.2 and CO.sub.2 from the second accommodation part and includes a cryogenic separation device to separate CO.sub.2 from a gas component in the discharge.

A cryogenic carbon capture system includes a flue gas cooling device in fluid communication with a heat engine. The flue gas cooling device receives a fluid stream that is downstream from the heat engine and a cooled liquid coolant stream so that the fluid stream is cooled by the cooled liquid coolant stream and a cooled flue gas stream is formed. A cryogenic carbon capture unit receives at least a portion of the cooled flue gas stream and separates carbon dioxide from the first portion of the cooled flue gas stream so that a clean flue gas stream and a carbon dioxide stream are formed. A liquid coolant cooling device receives the clean flue gas stream and a liquid coolant stream and cools the liquid coolant stream using the clean flue gas stream so that the cooled liquid coolant stream is formed and provided to the flue gas cooling device. The heat engine is in fluid communication with the cryogenic carbon capture system and receives a portion of a split stream that is downstream from the flue gas cooling device as an exhaust gas recirculation stream and an air stream.

A CO2 separation and liquefaction system such as might be used in a carbon capture and sequestration system for a fossil fuel burning power plant is disclosed. The CO2 separation and liquefaction system includes a first cooling stage to cool flue gas with liquid CO2, a compression stage coupled to the first cooling stage to compress the cooled flue gas, a second cooling stage coupled to the compression stage and the first cooling stage to cool the compressed flue gas with a CO2 melt and provide the liquid CO2 to the first cooling stage, and an expansion stage coupled to the second cooling stage to extract solid CO2 from the flue gas that melts in the second cooling stage to provide the liquid CO2.