Provided herein are systems and methods for the processing of exhaust gases of industrial processes in order to reduce or eliminate emission of pollutants (including carbon dioxide) and store energy in the form of cryogenic liquids. Advantageously, the provided systems and methods utilize advanced heat exchanger systems to reduce or eliminate the net power required for operation. The heat exchangers are used both to reduce effluent gases to liquid temperatures as well as reheat previously cooled and separated gases, which can generate electricity via a turbo generator. The described systems and method may also produce cryogenic liquid products (Argon, Krypton, liquid Oxygen, liquid Nitrogen, etc.).

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.

Offshore systems and methods may be configured for offshore power generation and carbon dioxide injection for enhanced gas recovery for gas reservoirs. For example, a method may include: providing an offshore facility including a gas turbine, and a gas separator; producing a produced gas from a gas reservoir to the offshore facility; combusting the produced gas in a gas turbine to produce power and a flue gas; at least partially removing nitrogen from the flue gas in a gas separator to produce a carbon dioxide-enriched flue gas and a nitrogen-enriched flue gas; compressing the carbon dioxide-enriched flue gas in a gas compressor to produce a compressed gas; and injecting the compressed gas from the gas compressor into the gas reservoir, wherein 80 mol % or more of hydrocarbon in the produced gas is combusted and/or injected into the gas reservoir.

An enhanced oil recovery method in which carbon dioxide is injected into a well to pressure the well or add lift a production flow from the well recaptures the injected carbon dioxide for reinjection into the well for lift or into another well in a group of for pressuring the well or adding lift to the production flow from the well. Geothermal energy in the production stream can be converted to electrical power for use in the recapturing of the carbon dioxide or other operations at the well site.

A method and system are disclosed for safe, efficient, economically productive, environmentally responsible, extraction and utilization of dissolved gases in deep waters of a rare type of “exploding” lake, where methane (CH.sub.4) is accompanied by abundant CO.sub.2. CH.sub.4 is combusted to generate electricity. CO.sub.2 usually is considered a contaminant requiring removal to avoid power loss. Cleaning high CO.sub.2 levels from CH.sub.4, however, is costly and causes CH.sub.4 loss. Venting CO.sub.2 is environmentally undesirable. Or, if CO.sub.2 is disposed in water flow returned to the deep lake, danger persists. CO.sub.2 and CH.sub.4 are degassed efficiently together and input into oxy-fuel combustion. Three process outputs are: degassed nutrients-rich water flow, power and CO.sub.2+H.sub.2O exhaust, all usable for industrially productive purposes. Extracting and using both gases together in an integrated method advances safety, economic productivity and environmental stewardship. Previously, it has not been possible to accomplish these ends together. The invention provides a hyper-efficient way.

The invention relates to a method for operating a gas turbine power plant, including a gas turbine, a HRSG following the gas turbine, an exhaust gas blower, and a carbon dioxide separation plant which separates the carbon dioxide contained in the exhaust gases and discharges it to a carbon dioxide outlet, the gas turbine, HRSG, exhaust gas blower, and carbon dioxide separation plant being connected by means of exhaust gas lines. According to the method a trip of the gas turbine power plant includes the steps of: stopping the fuel supply, switching off the exhaust gas blower, and controlling the opening angle of a VIGV at a position bigger or equal to a position required to keep a pressure in the exhaust gas lines between the HRSG and the exhaust gas blower above a minimum required pressure. The invention relates, further relates to a gas turbine power plant configured to carry out such a method.

A system and method for the simultaneous sequestration of CO2, production of hydrogen, and production of electricity at any iron and steel industries is described. In one illustrative example, the raw materials particularly used in a blast furnace can also be used for locking CO2 gas in the form of siderite. Siderite, thus formed, can be decomposed to generate pure CO2 gas. Eventually, the generated pure CO2 gas can be sequestered underground, sold or used for oil gas recovery or for other applications.

In a gas turbine system including a first gas turbine generator, a heat recovery steam generator and a steam turbine generator heat rejection system, the present invention relates to a method for CO.sub.2 capture from flue gas in said system, said method including: (a) diverting an amount of heat recovery steam generator flue gas from the CO.sub.2 capture plant; and (b) mixing the diverted heat recovery steam generator flue gas with an air stream, forming a combined gas stream, wherein (1) the combined gas stream is fed to a second gas turbine generator; (2) exhaust gas from the second gas turbine generator is mixed with exhaust gas from the first gas turbine generator, forming a combined exhaust gas stream; and (3) the combined exhaust gas stream enters the heat recovery steam generator, with the CO.sub.2 content of the combined exhaust gas stream increased through supplementary firing in the heat recovery steam generator.

The present techniques are directed to a system and method for generating power and recovering methane from methane hydrates. The system includes a low emissions power plant configured to generate power, wherein an exhaust gas from the low emissions power plant provides a gas mixture including nitrogen and carbon dioxide. The system also includes a methane recovery system configured to recover methane from methane hydrates by injecting the nitrogen and the carbon dioxide from the gas mixture into the methane hydrates.

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.