Devices and methods for reduction of NOx emissions from lean burn engines

A power generation system comprising:

• an engine operative to produce an exhaust stream;
• an exhaust system comprising a fuel processor configured to receive the exhaust stream, the fuel processor comprising a main chamber and a fuel reforming catalyst within the main chamber, the fuel processor having a fixed structure for dividing the exhaust stream between a first flow path through the catalyst, or a portion thereof, and a second flow within the main chamber that bypasses the first flow path, with the spilt ratio of the division between the two flow paths being unregulated or regulated only by the fixed structure, the exhaust system being structured to recombine the divided exhaust stream downstream from the catalyst;
• and
• a fuel injector configured to inject fuel into the first flow path without simultaneously injecting fuel into the bypass flow path, whereby the fuel injector is functional to produce rich conditions in the first flow path while conditions remain lean in the bypass flow.