Assembly and method for reducing nitrogen oxides, carbon monoxide, hydrocarbons and hydrogen gas in exhausts of internal combustion engines and producing an electrical output

1. A method of operating a catalytic system for reducing emissions from a rich burn spark-ignited engine and for generating electric power, the method comprising:

controlling intake air and fuel (AFR) to the rich burn spark-ignited engine to produce first exhaust gases having a first oxygen content;

passing said first exhaust gases into a first-stage catalyst chamber containing a three-way catalyst (TWC) operating at 800° F. to 1,250° F., which minimizes NOx content by reducing NOx (to N 2 and O 2 );

passing second exhaust gases exiting from the first-stage catalyst chamber to a (1) thermoelectric generator (TEG) for generating electric power and (2) to a thermoelectric generator exhaust conduit;

directing TEG output exhaust gases from the thermoelectric generator exhaust conduit to a fluid cooler to cool said TEG output exhaust gases, and thereafter enriching said TEG output exhaust gases to a second oxygen content,

wherein the fluid cooler comprises a cooling water injection conduit in communication with the thermoelectric generator exhaust conduit; and

passing the oxygen-enriched TEG output exhaust gases to a second-stage catalyst chamber containing a catalyst that minimizes CO content by oxidizing CO to CO 2 .

2. The method of claim 1 , further comprising producing said first exhaust gases using a stationary engine in a combined heat and power (CHP) application.

3. The method of claim 1 , wherein the fluid cooler further comprises a cooling air injection conduit in communication with the thermoelectric generator exhaust conduit.

4. The method of claim 1 , further comprising:

bypassing a portion of the second exhaust gases exiting from the first-stage catalyst chamber to a TEG bypass conduit; and

combining the bypass portion and the TEG output exhaust gases to form a combined output.