Steam-generating combustion system and method for emission control using oxygen enhancement

A method of steam-generating combustion, comprising:

• providing an oxidant enriched gas stream with an oxygen content of 21% to 100%;
• creating an oxidant stream containing the oxygen enriched gas stream;
• combusting a fuel in the oxidant stream in a steam-generating combustion chamber and generating flue gas having a flue gas mass flow rate which is smaller than a mass flow rate of flue gas generated by the combustion chamber when operated with the same mass flow rate of fuel and with air as the oxidant stream;
• and
• reducing the amount of at least one of particulate matter, SOx, NOx, and mercury in the flue gas with a flue gas pollutant control system.

A method of retrofitting or repowering a commercial air-fired, steam-generating combustion system to reduce overall cost of emission control, the method comprising:

• adding an oxygen-enriched gas generation system to the air-fired, steam-generating combustion system to deliver an oxygen enriched stream with 21% to 100% oxygen;
• delivering the oxygen-enriched stream to an oxidant delivery system to produce an oxidant stream for the combustion chamber of the combustion system;
• achieving a reduced mass flow rate of flue gas exiting the combustion chamber due to enhancement of the oxidant with the oxygen-enriched gas stream;
• and
• modifying a flue gas pollution control system of the combustion system to take advantage of the flue gas mass flow rate reduction.