The present disclosure relates to systems and methods that provide a low pressure liquid CO.sub.2 stream. In particular, the present disclosure provides systems and methods wherein a high pressure CO.sub.2 stream, such as a recycle CO.sub.2 stream from a power production process using predominately CO.sub.2 as a working fluid, can be divided such that a portion thereof can be expanded and used as a cooling stream in a heat exchanger to cool the remaining portion of the high pressure CO.sub.2 stream, which can then be expanded to form a low pressure CO.sub.2 stream, which may be in a mixed form with CO.sub.2 vapor. The systems and methods can be utilized to provide net CO.sub.2 from combustion in a liquid form that is easily transportable.

The present techniques are directed to a system and method for recovering carbon dioxide (CO.sub.2). The method includes recovering the CO.sub.2 from a gas mixture including the CO.sub.2 via a CO.sub.2 separation system. The CO.sub.2 separation system includes a rotating freezer/melter.

A refrigeration system for condensation of carbon dioxide (CO.sub.2) in a flue gas stream, the system includes a refrigeration circuit, a flue gas treatment system that includes a flue gas compressor, a flue gas adsorption drier, and a refrigeration system for condensation of CO.sub.2; and a method for condensation of CO.sub.2 in a flue gas stream using a circulating stream of an external refrigerant.

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 for generation of electrical power and/or steam or vapour, by combustion of carbonaceous fuels, where carbonaceous fuel is combusted in a combustion chamber at a pressure of 40 to 200 bar in the presence of oxygen enriched air or substantially pure oxygen to produce electrical power and/or to generate steam from fluids circulating in steam tubes arranged inside the combustion chamber, and a flue gas, where the flue gas is withdrawn from the combustion chamber and is cooled to a temperature that results in condensation of the flue gas, or conversion of the flue gas to a supercritical fluid having a density of at least 600 kg/m.sup.3, and where the liquid or supercritical fluid formed, is safely deposited, and a plant for carrying out the method, are described.

A method of and control apparatus for operation of a boiler plant are described. The boiler plant has a furnace volume, an oxyfuel firing system for oxyfuel combustion of fuel in the furnace volume, and a compression system for compression of gases exhausted from the furnace volume after combustion. The method and control apparatus are characterized by the step of controlling mass flow of gases through the compression system as a means to control pressure within the furnace volume. This invention relates to both single and multi unit arrangements.

Proposed is a carbon dioxide and sulfur oxide capture and carbon resource conversion system for coal-fired power generation, the system being capable of capturing and converting carbon dioxide in an exhaust gas into a carbon resource by using a basic alkaline mixture solution, thereby being capable of reducing carbon dioxide and also capable of manufacturing sodium carbonate or sodium bicarbonate. In the system, sodium carbonate or sodium bicarbonate manufactured from the captured carbon dioxide is used as a desulfurization agent capturing sulfur oxide in an exhaust gas discharged from a coal-fired power generation plant, and carbon dioxide and sulfur oxide are simultaneously captured, so that an additional flue gas desulfurization equipment is not required to be mounted. Accordingly, the installation space of the desulfurization equipment for removing pollutants contained in gas introduced into carbon dioxide capture equipment may be minimized, and the process cost may be reduced.

A system includes a turbine combustor that includes a head end portion having a head end chamber, a combustion portion having a combustion chamber disposed downstream from the head end chamber, a cap disposed between the head end chamber and the combustion chamber, and a flow separator configured to separate a first exhaust flow from an oxidant flow. The flow separator is configured to direct the first exhaust flow into the head end chamber. The turbine combustor also includes a mixing region configured to mix the first exhaust flow with the oxidant flow to provide an oxidant-exhaust mixture.

A chemical looping system that contains an oxidizer and a reducer is in fluid communication with a gas purification unit. The gas purification unit has at least one compressor, at least one dryer; and at least one distillation purification system; where the gas purification unit is operative to separate carbon dioxide from other contaminants present in the flue gas stream; and where the gas purification unit is operative to recycle the contaminants to the chemical looping system in the form of a vent gas that provides lift for reactants in the reducer.

A method for isolating substantially pure carbon dioxide from flue gas is provided. The method can include combusting carbon based fuel to form flue gas; cooling the flue gas to provide substantially dry flue gas; removing N.sub.2 from the dry flue gas to provide substantially N.sub.2 free flue gas CO.sub.2; and liquifying the substantially N.sub.2 free flue gas CO.sub.2 to form substantially pure carbon dioxide.