Method and apparatus for sequentially staged combustion using a catalyst

摘要

A low NOx generating combustor in which a first lean mixture of fuel and air is pre-heated by transferring heat from hot gas discharging from the combustor. The pre-heated first fuel/air mixture is then catalyzed in a catalytic reactor and then combusted so as to produce a hot gas having a temperature in excess of the ignition temperature of the fuel. Second and third lean mixtures of fuel and air are then sequentially introduced into the hot gas, thereby raising their temperatures above the ignition temperature and causing homogeneous combustion of the second and third fuel air mixtures. This homogeneous combustion is enhanced by the presence of the free radicals created during the catalyzation of the first fuel/air mixture. In addition, the catalytic reactor acts as a pilot that imparts stability to the combustion of the lean second and third fuel/air mixtures.