PURPOSE: To enhance the efficiency of a coal burner by a method wherein a double tube is formed inside a powder feed tube, pulverized coal and char are made to flow separately into a central flow path and its outer cylindrical tube respectively, and a particle mixing chamber is provided in the front end interior of the power feed tube while a gasifying mixing chamber is provided in a burner outlet end portion.

CONSTITUTION: A central flow path 4 of a pulverized coal feed tube 13 is embedded in a powder feed tube 5. Char 1 containing therein a large amount of unburnt carbon which is scattered from a gasifying furnace and is collected is fed under pressure into an annular tube 12 formed by the powder feed tube 5 and the pulverized coal feed tube 13 and flows out through an outlet port 19. The pulverized coal feed tube 13 and the powder feed tube 5 are integrated. In the front end interior of the powder feed tube is provided a particle mixing chamber 15 in which pulverized coal 17 is made to mix with the char 1, and further a gasifying mixing chamber 16 is provided so that after both of the pulverized coal and the char have been well mixed, a gasifying agent (oxygen or air), which is ejected from gasifying agent outlet ports 8 within the front end of an outer cylindrical tube 9, is brought into favorable contact with the pulverized coal + char. After the particles and the gasifying agent have been promoted in their good contact, they are ejected through an ejection port 11.