The present invention relates to systems and methods for controlling a power production plant and optionally providing a one or more product streams for an end use thereof. Control of a power production plant specifically can include executing one or more functions effective for adjusting a heat profile of a heat exchange unit (HEU) operating with a plurality of streams passing therethrough. This can include implementing a control function that alters a flow of one or more of the plurality of streams by adding flow to or withdrawing flow one or more of the plurality of streams at an intermediate temperature range within the HEU at a point that is positioned between a first end and a second end of the HEU.

In a method for operating a combustor of an embodiment, before ignition in the combustor, a mixed gas containing oxygen is circulated through the combustor as a circulating gas. Then, in an operating time from the time of ignition in the combustor to the time of a rated load of a turbine, from the time of ignition until reaching stable combustion conditions allowing stable combustion, a combustion gas in which a controller controls a flow rate of a fuel supplied from a fuel supply part and a flow rate of an oxidant supplied from an oxidant supply part to maintain the same oxygen concentration as an oxygen concentration in the mixed gas is circulated as the circulating gas.

A power production facility comprises a power plant that combusts fuel to produce energy for generating electricity and exhaust gas, an emissions capture unit to receive the exhaust gas to remove pollutants, a fuel cell to generate electricity via reaction of constituents and provide byproduct heat to operate the emissions capture unit, and an electrolyzer to generate constituents for the fuel cell from water byproduct received from the fuel cell resulting from the reaction process. A method of generating power with an emissions capture unit comprises providing a hybrid power plant configured to generate hydrogen gas and oxygen gas with an electrolyzer from a water input using an electrical input, generate electricity, heat and the water input with a fuel cell from the hydrogen gas and oxygen gas of the electrolyzer, and capture emissions from exhaust gas with an emissions capture unit using the heat from the fuel cell.

A power production facility comprises a power plant that combusts fuel to produce energy for generating electricity and exhaust gas, an emissions capture unit to receive the exhaust gas to remove pollutants, a fuel cell to generate electricity via reaction of constituents and provide byproduct heat to operate the emissions capture unit, and an electrolyzer to generate constituents for the fuel cell from water byproduct received from the fuel cell resulting from the reaction process. A method of generating power with an emissions capture unit comprises providing a hybrid power plant configured to generate hydrogen gas and oxygen gas with an electrolyzer from a water input using an electrical input, generate electricity, heat and the water input with a fuel cell from the hydrogen gas and oxygen gas of the electrolyzer, and capture emissions from exhaust gas with an emissions capture unit using the heat from the fuel cell.

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 configured for simultaneous hydrogen production. Beneficially, substantially all carbon arising from combustion in power production and hydrogen production is captured in the form of carbon dioxide. Further, produced hydrogen (optionally mixed with nitrogen received from an air separation unit) can be input as fuel in a gas turbine combined cycle unit for additional power production therein without any atmospheric CO.sub.2 discharge.

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 configured for simultaneous hydrogen production. Beneficially, substantially all carbon arising from combustion in power production and hydrogen production is captured in the form of carbon dioxide. Further, produced hydrogen (optionally mixed with nitrogen received from an air separation unit) can be input as fuel in a gas turbine combined cycle unit for additional power production therein without any atmospheric CO.sub.2 discharge.

A system may include a turbine and a recuperative heat exchanger system. The recuperative heat exchanger system is configured to receive exhaust gases from the turbine. The recuperative heat exchanger system may include a precool section to cool the exhaust gases, a major heating section to receive the cooled the exhaust gases, and a minor heating section to receive the cooled the exhaust gases.

A system may include a turbine and a recuperative heat exchanger system. The recuperative heat exchanger system is configured to receive exhaust gases from the turbine. The recuperative heat exchanger system may include a precool section to cool the exhaust gases, a major heating section to receive the cooled the exhaust gases, and a minor heating section to receive the cooled the exhaust gases.

There is disclosed a fan assembly including a fan rotor including a hub and fan blades. The fan blades have a leading edge and a trailing edge. A fan stator downstream of the fan rotor relative to a direction of an airflow through the fan assembly. The fan stator includes vanes extending between radially inner ends and radially outer ends. A flow recirculation circuit has an inlet downstream of the vanes of the fan stator and an outlet upstream of the vanes. A recirculation rotor has a plurality of airfoils circumferentially distributed around the axis and located in the flow recirculation circuit. The recirculation rotor is rotatable about the axis within the recirculation circuit. A method of operating the fan assembly is also disclosed.

There is disclosed a fan assembly including a fan rotor including a hub and fan blades. The fan blades have a leading edge and a trailing edge. A fan stator downstream of the fan rotor relative to a direction of an airflow through the fan assembly. The fan stator includes vanes extending between radially inner ends and radially outer ends. A flow recirculation circuit has an inlet downstream of the vanes of the fan stator and an outlet upstream of the vanes. A recirculation rotor has a plurality of airfoils circumferentially distributed around the axis and located in the flow recirculation circuit. The recirculation rotor is rotatable about the axis within the recirculation circuit. A method of operating the fan assembly is also disclosed.