Method and device for flameless stepwise combustion

Abstract

A method for heating a heating chamber to a temperature below the spontaneous ignition temperature of the fuel that is used, wherein fuel and air are reacted in flameless oxidation in a non-stoichiometric mixture ratio in a combustion chamber. The air ratio λ is at least lower than the stoichiometric ratio λ=1 such that the temperature in the combustion chamber does not exceed the temperature at which thermal nitrous oxide generation begins. Otherwise, λ is established such that the spontaneous ignition temperature of the fuel is exceeded. This results in two permissible air ratio ranges, between λmin and λ1 in sub-stoichiometric operation, and λ2 to λmax in superstoichiometric operation of the combustion chamber. The still-reactive gases released from the combustion chamber are made to react in the heating chamber, preferably by flameless oxidation. This avoids thermal nitrous oxide generation in the heating chamber.

Dependencies are inferred from the claim text.