| 摘要 |
The invention relates to a process and a central burner for heating shaft furnaces, as are customary for the heat treatment of mineral material, in which a combustible gas or gas-air mixture emerges in each case from the upper and lower part of the burner head and, therebetween, spreading air emerges into the shaft of the furnace from the central part of the burner head. The object of the invention is to design a central burner so that it is suitable both for operation with natural gas as the fuel and for combined operation with coal dust and natural gas. To achieve this object, it is proposed that coal dust (13') be allowed to emerge in addition to the gas-air mixture (10') in the upper part, and also below the spreading air (16') in the central part, of the burner head (1) and an inert gas or a gas-air mixture (25') having a hypostoichiometric mixing ratio be allowed to emerge below the lower discharge (22) of coal dust (21'). A burner suitable for this has a cylindrical burner head (1), in which there are provided, at a horizontally lateral distance beside the openings (11) of the upper part and also at a vertical distance from and between the openings (19) for the spreading air (16'), further openings (22, 33) for the emergence of coal dust (13', 21'), the lowermost of these openings (22) being arranged above the openings (26) for the discharge of the gas-air mixture (25'). |
