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.

A gas turbine plant includes a gas turbine, an exhaust line, an exhaust heat recovery boiler that generates steam due to heat of exhaust gas and guides the exhaust gas to the exhaust line, a carbon dioxide recovery device that recovers carbon dioxide contained in the exhaust gas, a heat exchanger that cools the exhaust gas to a temperature set in advance, and a circulation line that branches from a position between the carbon dioxide recovery device and the heat exchanger and is connected to an inlet of the gas turbine. The carbon dioxide recovery device has an absorption tower that absorbs carbon dioxide contained in the exhaust gas by causing the exhaust gas at the set temperature and an absorption liquid to come into contact with each other. The heat exchanger is formed of a material having higher corrosion resistance than a material forming the exhaust heat recovery boiler.

The supercritical CO.sub.2 turbine in an embodiment includes: a rotary body; a stationary body housing the rotary body inside; and a turbine stage including a stator blade cascade in which a plurality of stator blades are supported inside the stationary body, and a rotor blade cascade in which a plurality of rotor blades are supported by the rotary body inside the stationary body, in which a supercritical CO.sub.2 working medium is introduced into the inside of the stationary body and flows via the turbine stage in an axial direction of the rotary body to thereby rotate the rotary body. Here, a thermal conductivity k1 and a specific heat c1 of a material constituting the rotary body and a thermal conductivity k2 and a specific heat c2 of a material constituting the stationary body satisfy a relationship represented by the following formula (A).

k1/c1≤k2/c2  formula (A)

A CO.sub.2 gas turbine facility of an embodiment includes: a combustion apparatus which combusts fuel and an oxidant to produce a combustion gas to be introduced into a turbine; a pipe which circulates carbon dioxide in a working fluid discharged from the turbine through the combustion apparatus as a cooling medium; and a bypass pipe which introduces a fluid at a lower temperature than a temperature of carbon dioxide flowing through the pipe into the pipe.

The invention provides a CO.sub.2 turbine power generation system that can be easily prevented from reaching an overspeed condition. A CO.sub.2 turbine power generation system of an embodiment includes a CO.sub.2 medium shutoff valve installed in a medium flow path between a regenerative heat exchanger and a combustor. When load rejection is to be performed, the CO.sub.2 medium shutoff valve closes to shut off the supply of the medium from the regenerative heat exchanger to the combustor.

Methods and systems for increasing efficiency of combustion in a turbine, methods including expanding in an expansion unit a pressurized fluid stream to form an expanded, cooled fluid stream; exchanging heat between an oxygen containing stream and the expanded, cooled fluid stream to reduce temperature of the oxygen containing stream to a reduced temperature and create a reduced temperature turbine compressor inlet oxygen containing stream; and compressing the reduced temperature turbine compressor inlet oxygen containing stream to an operating pressure of the turbine, where the step of compressing the reduced temperature turbine compressor inlet oxygen containing stream is more efficient than compressing the oxygen containing stream.

The present invention is an integrated system of a carbon dioxide capturing processes from the atmosphere and producing electrical energy from the integrated system.

The objective of the current invention is; capturing carbon dioxide from the air through the tree fashioned carbon dioxide capturing system and generating electric power through the integrated systems. To generate electric power at maximum efficiency, and capture carbon dioxide, the present invention comprises different integrated processes, integrated systems, and techniques. The present system comprises; an ionized and non-ionized hydrogen gas turbine system unit, carbon dioxide capturing tree system unit, a hybrid thermoelectric-generator and solid oxide fuel cell system unit, a hybrid hydrogen-chlorine fuel cell and carbon dioxide reactor core system unit.

Furthermore to capture carbon dioxide and generate electric power, the present invention comprises various other alternative embodiments.

Disclosed is an improved method and system of operating the semi-closed cycle, which both reduces parasitic loads for oxygen generation and for gas clean up, while also reducing, capital cost of the gas clean up plant (reduced drying requirement) and of the oxygen plant (enabling membranes vs. mole sieves). The invention is applicable to piston or turbine engines, and results in a near fully non-emissive power system via the Semi-Closed Cycle (SCC), in a manner which both captures carbon in the form of carbon dioxide, CO2, and in a manner which improves the efficiency and cost effectiveness of prior disclosures. The captured carbon is of a purity and pressure directly suitable for Enhanced Oil Recovery (EOR), sequestration, or industrial use.

The present disclosure relates to systems and methods wherein a dilute hydrocarbon stream can be oxidized to impart added energy to a power production system. The oxidation can be carried out without substantial combustion of the hydrocarbons. In this manner, dilute hydrocarbon streams that would otherwise be required to undergo costly separation processes can be efficiently utilized for improving the power production system and method. Such systems and methods particularly can utilize dilute hydrocarbon stream including a significant amount of carbon dioxide, such as may be produced in hydrocarbon recovery process, such as enhanced oil recovery or conventional hydrocarbon recovery processes.

A method of generating electric power includes expanding a flow of exhaust gas from a combustion process as the exhaust gas passes through a turbo-expander disposed on a turbo-crankshaft. The flow of exhaust gas from the turbo-expander is routed through an absorber section of an open cycle absorption chiller system. Water from the exhaust gas is absorbed via a first refrigerant solution disposed in the absorber section as the exhaust gas passes through the first refrigerant solution and out of the absorber section. The flow of exhaust gas from the absorber section is compressed as the exhaust gas passes through a turbo-compressor disposed on the turbo-crankshaft. Electrical power is generated from a bottoming cycle generator disposed on the turbo-crankshaft.