초록

A new combustion process wherein combustion efficiency is retained while reducing inlet air temperature to the combustor so as to obtain both reduced nitrogen oxides emissions and reduced CO emissions. A new combination of combustion apparatus and heat utilization apparatus are also provided.

대표청구항 ▼

In a method for forming and burning a combustible mixture of a fuel and air in a combustion zone having a primary combustion region, a secondary combustion region located downstream from said primary combustion region, and a quench or dilution region located downstream from said secondary combustion

In a method for forming and burning a combustible mixture of a fuel and air in a combustion zone having a primary combustion region, a secondary combustion region located downstream from said primary combustion region, and a quench or dilution region located downstream from said secondary combustion region, to produce hot combustion gases containing heat energy which are passed to a heat energy utilization zone to utilize a portion of said heat energy, and wherein, there are established a first stream of air and a second stream of air, at least a portion of said first stream of air is introduced into said primary combustion region as the sole stream of primary combustion air introduced thereto, a stream of fuel is introduced into said primary combustion region, said second stream of air is passed in heat exchange relationship with an exhaust stream from said heat energy utilization zone to heat said second stream of air, and at least a portion of said heated second stream of air is passed into said quench or dilution region, the improvement comprising: introducing said at least a portion of said first stream of air into said primary combustion region at a temperature within the range of from ambient to about 700°F. and at a controlled rate, and adjusting said rate in accordance with the rate of introduction of said fuel to be sufficient, when said fuel is burned, to provide in said primary combustion region a combustion gas temperature within the range of from about 2500°to about 3000°F at which the rate of formation of NOx is reduced and at which the rate of oxidation of CO to CO2 is not substantially reduced; and introducing another portion of said heated second stream of air into said secondary combustion region at a temperature greater than the temperature of said first stream of air and at a rate which are sufficient to provide in said secondary combustion region a combustion gas temperature at which the concentration of CO pollutant in the combustion gases in said secondary combustion region is reduced and at which the concentration of said NOx pollutant is not increased.