OIL FIRING BURNER, SOLID FUEL FIRING BURNER UNIT AND BOILER FOR SOLID FUEL FIRING

摘要

PROBLEM TO BE SOLVED: To provide an oil firing burner capable of preventing or restricting the early dispersion toward the flame circumference of the secondary air charged from an oil firing burner during combustion of solid fuel such as dust coal while ensuring burning quality during oil combustion.SOLUTION: An oil firing burner 30A, disposed adjacent to the circumference of a pulverized-coal burner, comprises: a substantially rectangular cross-sectional oil gun 32 disposed at the delivery opening center of a nozzle body 31 for charging oil fuel; and a secondary air input port 40 disposed to surround the circumference of the oil gun 32. The secondary air input port 40 includes: a central circular arc part 41 in a shape approximately similar to a circular diffuser 34 fixed on the tip side of the oil gun 32; and rectangular parts 42L and 42R continuously disposed on both sides of the central circular arc part 41 in which the interface in an adjacent direction is reduced so as to increase the clearance with the pulverized-coal burner.