Control method for stoichiometric exhaust gas recirculation power plant

摘要

Ambient air is compressed into a compressed ambient gas flow with a main air compressor. The compressed ambient gas flow having a compressed ambient gas flow rate is delivered to a turbine combustor and mixed with a fuel stream having a fuel stream flow rate and a portion of a recirculated low oxygen content gas flow to form a combustible mixture. The combustible mixture is burned and forms the recirculated low oxygen content gas flow that drives a turbine. A portion of the recirculated low oxygen content gas flow is recirculated from the turbine to the turbine compressor using a recirculation loop. The compressed ambient gas flow rate and the fuel stream flow rate are adjusted to achieve substantially stoichiometric combustion. An excess portion, if any, of the compressed ambient gas flow is vented. A portion of the recirculated low oxygen content gas flow is extracted using an extraction conduit.

主权项

1. A method for controlling a stoichiometric exhaust gas recirculation power plant arrangement, comprising the steps of:
compressing ambient air into a compressed ambient gas flow with at least one main air compressor; delivering at least a first portion of the compressed ambient gas flow through a first conduit, with a compressed ambient gas flow rate, to a turbine combustor that is fluidly connected via the first conduit to the at least one main air compressor; delivering a fuel stream, having a fuel stream flow rate, to the turbine combustor for mixing with the at least first portion of the compressed ambient gas flow delivered from the at least one main air compressor via the first conduit and with at least a first portion of a recirculated low oxygen content gas flow delivered via a second conduit from a turbine compressor to form a combustible mixture; burning the combustible mixture in the turbine combustor and thereby forming the recirculated low oxygen content gas flow and driving a turbine connected to the turbine compressor via a turbine shaft; recirculating the at least first portion of the recirculated low oxygen content gas flow from the turbine to the turbine compressor using a recirculation loop; bypassing at least a portion of the at least first portion of the recirculated low oxygen content gas flow from the turbine combustor and turbine with a bypass conduit having an inlet on the recirculation loop between the turbine compressor and the turbine combustor and an outlet on the recirculation loop downstream of the turbine; adjusting at least one of the compressed ambient gas flow rate and the fuel stream flow rate to achieve substantially stoichiometric combustion; venting an excess portion, if any, of the at least first portion of the compressed ambient gas flow at a location between the at least one main air compressor and the turbine combustor; extracting at least a second portion of the recirculated low oxygen content gas flow using an extraction conduit that is fluidly connected to the bypass conduit, such that the mass balance of the power plant remains substantially constant; and cooling the turbine by delivering a secondary flow through a secondary flow path, wherein the secondary flow path delivers at least a third portion of the recirculated low oxygen content gas flow from the turbine compressor to the turbine for cooling and sealing the turbine and thereafter into the recirculation loop.