Ultra-low pollutant emission combustion process and apparatus

Claim 1

An apparatus for ultra-low pollutant emission combustion of fossil fuel comprising: a first upstream end, a first downstream end and a first wall defining an elongated cyclonic primary combustion chamber, said primary combustion chamber having an elongated cyclonic cross-sectional area about 4 to about 30 percent of the cross-section area of an elongated cyclonic secondary combustion chamber and a volume about 1 to about 20 percent of a combined volume of said primary and secondary combustion chambers; a second upstream end, a second downstream end and a second wall defining said secondary combustion chamber, said primary combustion chamber in communication with said secondary combustion chamber; a dilution chamber upstream end, a dilution chamber downstream end and a dilution chamber wall defining an elongated cyclonic dilution chamber, dilution chamber discharge means in communication with said dilution chamber, said secondary combustion chamber in communication with said dilution chamber; primary inlet means in communication with said primary combustion chamber for introducing a first fuel portion of about 1 percent to about 20 percent of a total amount of the fossil fuel to be burned in the apparatus and for introducing primary combustion air into said primary combustion chamber in an amount selected from one of a first range of about 40 percent to about 90 percent of a first stoichiometric requirement for complete combustion of said first fuel portion and a second range of about 140 percent to about 230 percent of the first stoichiometric requirement for complete combustion of said first fuel portion; said primary inlet means tangentially mounted with respect to said first wall, ignition means for igniting a mixture of aid first fuel portion and said primary combustion air within said primary combustion chamber; secondary inlet means in communication with said secondary combustion chamber for introducing a second fuel portion of about 80 percent to about 99 percent of said total amount of the fossil fuel to be burned in the apparatus and for introducing secondary combustion air into said secondary combustion chamber in an amount of about 150 percent to about 260 percent of a second stoichiometric requirement for complete combustion of said second fuel portion; said secondary inlet means tangentially mounted with respect to said second wall; and dilution air inlet means in communication with said dilution chamber for introducing dilution air into said dilution chamber.

Claim 2

An apparatus for ultra-low pollutant emission combustion of fossil fuel comprising: a first upstream end, a first downstream end and a first wall defining an elongated cyclonic primary combustion chamber, said primary combustion chamber having an elongated cyclonic cross-sectional area about 4 to about 30 percent of the cross-section area of an elongated cyclonic secondary combustion chamber and a volume about 1 to about 20 percent of a combined volume of said primary and secondary combustion chambers; a second upstream end, a second downstream end and a second wall defining said secondary combustion chamber, said primary combustion chamber in communication with said secondary combustion chamber; a dilution chamber upstream end, a dilution chamber downstream end and a dilution chamber wall defining an elongated cyclonic dilution chamber, dilution chamber discharge means in communication with said dilution chamber, said secondary combustion chamber in communication with said dilution chamber; primary inlet means in communication with said primary combustion chamber for introducing a first fuel portion of about 1 percent to about 20 percent of a total amount of the fossil fuel to be burned in the apparatus and for introducing primary combustion air into said primary combustion chamber in an amount selected from one of a first range of about 40 percent to about 90 percent of a first stoichiometric requirement for complete combustion of said first fuel portion and a second range of about 140 percent to about 230 percent of the first stoichiometric requirement for complete combustion of said first fuel portion; said primary inlet means tangentially mounted with respect to said first wall, ignition means for igniting a mixture of aid first fuel portion and said primary combustion air within said primary combustion chamber; secondary inlet means in communication with said secondary combustion chamber for introducing a second fuel portion of about 80 percent to about 99 percent of said total amount of the fossil fuel to be burned in the apparatus and for introducing secondary combustion air into said secondary combustion chamber in an amount of about 150 percent to about 260 percent of a second stoichiometric requirement for complete combustion of said second fuel portion; said secondary inlet means tangentially mounted with respect to said second wall; and dilution air inlet means in communication with said dilution chamber for introducing dilution air into said dilution chamber.

Claim 21

The method for ultra-low pollutant emission combustion of fossil fuel, the steps comprising: introducing into a primary combustion chamber a first fuel portion of about 1 percent to about 20 percent of a total fuel to be combusted; introducing primary combustion air into said primary combustion chamber in an amount selected from one of a first range of about 40 percent to about 90 percent of a first stoichiometric requirement for complete combustion of said first fuel portion and a second range of about 140 percent to about 230 percent of the first stoichiometric requirement for complete combustion of said first fuel portion; combusting said first fuel portion with said primary combustion air in said primary combustion chamber at a temperature about 2000° F. to about 2700° F. producing initial combustion products; passing said initial combustion products into a secondary combustion chamber; introducing into said secondary combustion chamber a second fuel portion of about 80 percent to about 99 percent of the total fuel to be combusted; introducing secondary combustion air into said secondary combustion chamber in an amount of about 150 percent to about 260 percent of a second stoichiometric requirement for complete combustion of said second fuel portion; combusting said second fuel portion and any remaining fuel in said initial combustion products with said secondary combustion air in said secondary combustion chamber at a temperature about 1700° F. to about 2600° F. producing final combustion products; passing said final combustion products into a dilution chamber; introducing dilution air into said dilution chamber producing ultra-low pollutant emission vitiated air at a temperature about 100° F. to about 2500° F.; and discharging said ultra-low pollutant emission vitiated air from said dilution chamber.

Claim 22

The method for ultra-low pollutant emission combustion of fossil fuel, the steps comprising: introducing into a primary combustion chamber a first fuel portion of about 1 percent to about 20 percent of a total fuel to be combusted; introducing primary combustion air into said primary combustion chamber in an amount selected from one of a first range of about 40 percent to about 90 percent of a first stoichiometric requirement for complete combustion of said first fuel portion and a second range of about 140 percent to about 230 percent of the first stoichiometric requirement for complete combustion of said first fuel portion; combusting said first fuel portion with said primary combustion air in said primary combustion chamber at a temperature about 2000° F. to about 2700° F. producing initial combustion products; passing said initial combustion products into a secondary combustion chamber; introducing into said secondary combustion chamber a second fuel portion of about 80 percent to about 99 percent of the total fuel to be combusted; introducing secondary combustion air into said secondary combustion chamber in an amount of about 150 percent to about 260 percent of a second stoichiometric requirement for complete combustion of said second fuel portion; combusting said second fuel portion and any remaining fuel in said initial combustion products with said secondary combustion air in said secondary combustion chamber at a temperature about 1700° F. to about 2600° F. producing final combustion products; passing said final combustion products into a dilution chamber; introducing dilution air into said dilution chamber producing ultra-low pollutant emission vitiated air at a temperature about 100° F. to about 2500° F.; and discharging said ultra-low pollutant emission vitiated air from said dilution chamber.