| 摘要 |
A method of firing granular carbonate minerals, for example a cement-calcine-forming meal, in which the comminuted solids are preheated in a fluidized bed or by like entrainment in a hot gas and then subjected to decarbonation in a precalcinator before entering a rotary kiln from which the cement clinker is discharged into a cooler for heat exchange between the hot clinker and air. According to the invention, the meal is suspended in the precalcinator, which forms an upright shaft at the inlet end of the kiln, so that the particles do not pass into the kiln directly from the precalcinator but rather can be entrained by the gases in the precalcinator, separated therefrom in a cyclone and delivered to the kiln. Fuel is mixed with the kiln exhaust gases just ahead of the zone at which the meal is suspended so that the sensible heat of the exhaust gas vaporizes the fuel or gasifies the latter. This mixture then contacts the meal and the oxygen-containing gas to ensure uniform heat transfer during oxidation of the gasified product to the meal to be subjected to decarbonation.
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