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 present disclosure relates to systems and methods that are useful for controlling one or more aspects of a power production plant. More particularly, the disclosure relates to power production plants and methods of carrying out a power production method utilizing different fuel chemistries. Combustion of the different fuel mixtures can be controlled so that a defined set of combustion characteristics remains substantially constant across a range of different fuel chemistries.

A method is disclosed for evaluating inerting concentration of a fire suppression agent. The method includes flowing air upward into a chimney tube and flowing fuel into the flowing air in the chimney tube. A targeted concentration of the fire suppression agent is introduced into the flowing air and into the flowing fuel in the chimney tube. An ignitor is ignited to provide ignition energy to the flowing air and the flowing fuel, and the ignitor is deactivated. The targeted concentration of the fire suppression agent is at or above the inerting concentration of the fire suppression agent if combustion of the flowing fuel does not persist beyond three seconds after the ignitor is deactivated.

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 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.

A method includes providing a furnace including a radiant heating zone having metal heating coils and burners, concurrently applying a combustion media, having a combustibility, and a diluent to the burners, the burners burning the combustion media producing flames heating the radiant heating zone, and the diluent reducing the combustibility of the combustion media for reducing heat generated by the flames for reducing heat degradation of the metal heating coils.

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 present disclosure relates to systems and methods that are useful for controlling one or more aspects of a power production plant. More particularly, the disclosure relates to power production plants and methods of carrying out a power production method utilizing different fuel chemistries. Combustion of the different fuel mixtures can be controlled so that a defined set of combustion characteristics remains substantially constant across a range of different fuel chemistries.

The present disclosure relates to systems and methods that are useful for controlling one or more aspects of a power production plant. More particularly, the disclosure relates to power production plants and methods of carrying out a power production method utilizing different fuel chemistries. Combustion of the different fuel mixtures can be controlled so that a defined set of combustion characteristics remains substantially constant across a range of different fuel chemistries.

The present invention relates to a method of combusting a fuel gas with a stoichiometric or near stoichiometric amount of molecular oxygen in the presence of a controlled amount of a diluent to enhance the extent of combustion reactions in high heat transfer environment. The energy released is utilized to heat a fluid by direct contact with the flame. The diluent can be different from the fluid to be heated with respect to composition, temperature or pressure. The diluent can be same as or derived from the fluid to be heated.