Inlet mixer for exhaust gas recirculation in power generation systems

A power generation system comprising:

• a rotary machine comprising:
• a compressor;
• and
• a turbine coupled to the compressor and configured to produce exhaust gases;
• and
• an exhaust gas recirculation (EGR) system configured to recirculate the exhaust gases from the turbine towards the compressor, the EGR system comprising an EGR mixer for mixing the exhaust gases being recirculated and a working fluid, the EGR mixer comprising:
• a mixing chamber defining a flow direction;
• a working fluid inlet coupled with the mixing chamber for introducing the working fluid into the mixing chamber along the flow direction;
• a plurality of exhaust gas injection ducts extending across the mixing chamber downstream from the working fluid inlet, each of the plurality of exhaust gas injection ducts oriented to receive the exhaust gases being recirculated and to inject the exhaust gases into the mixing chamber in a direction that intersects the flow direction to generate a turbulent flow within the mixing chamber;
• and
• an outlet coupled with the mixing chamber downstream from the plurality of exhaust gas injection ducts for directing a mixture of the exhaust gases and the working fluid to the compressor of the rotary machine.

A method of operating a power generation system that includes an exhaust gas recirculation (EGR) system including an EGR mixer, the EGR mixer including a mixing chamber, a working fluid inlet coupled with the mixing chamber, a plurality of exhaust gas injection ducts extending across the mixing chamber downstream from the working fluid inlet, and an outlet coupled with the mixing chamber downstream from the plurality of exhaust gas injection ducts, the method comprising:

• generating exhaust gases within the power generation system;
• recirculating at least a portion of the exhaust gases towards a compressor within the power generation system;
• introducing a working fluid into the mixing chamber of the EGR mixer along a flow direction via the working fluid inlet;
• injecting the exhaust gases being recirculated into the mixing chamber of the EGR mixer via the plurality of exhaust gas injection ducts in a direction that intersects the working fluid to generate turbulent flow within the mixing chamber and to produce a mixture of the exhaust gases and the working fluid;
• and
• directing the mixture to the compressor via the outlet of the EGR mixer.