PURPOSE: To increase the processing capacity of a furnace by dispersing fluid refuse having a low heat generation rate into the flame of an oxygen/fuel burner and burning it in the flame while confining the front of the flame within an incinerator and regulating the flame energy to keep a specified temperature in the incinerator.

CONSTITUTION: The burner 1 comprises a housing 5 having a water-cooled jacket, an oxygen/fuel burner 2 disposed in the center thereof, and a plurality of nozzles 3 arranged around the burner 2 in parallel therewith within an annular part 4. The burner 2 comprises a tubular water-cooled outer pipe 6, and an inner pipe 8 arranged concentrically to the outer pipe 6 and ending at a nozzle tip 7 for ejecting fuel or refuse. The inner pipe 8 comprises an outer pipe 9 and a central pipe 9' and fuel is fed through the pipe 8 to the nozzle tip 7 while air being atomized at the tip 7 is fed to the central pipe 9'. Fluid refuse having low heat generation rate is fed through the nozzle 3 into a flame confined within the furnace of the burner 2 and burnt and the flame is regulated by controlling the quantity thereof.