Patent ID: 7213522

Claim:
A combustion method for a solid burner comprising: a fuel nozzle for jetting a fluid mixture of a solid fuel and its carrier gas; and at least one air nozzle, arranged outside the fuel nozzle, for jetting air; wherein at least one additional air nozzle for jetting additional air having a velocity component in the circumferential direction of said fuel nozzle is provided in such a way as to project into said fuel nozzle; wherein the amount of air supplied from said additional air nozzle is increased when combustion load is low, and the amount of air supplied from the innermost air nozzle out of said air nozzles is decreased or the swirling flow velocity is increased; and wherein the amount of air supplied from said additional air nozzle is decreased when combustion load is high, and the amount of air supplied from the innermost air nozzle out of said air nozzles is increased or the swirling flow velocity is decreased.