| 摘要 |
Described is a plant for manufacturing cement clinker comprising a preheater (6) for preheating cement raw meal by contact with hot gases which preheater comprises a number of cyclone stages (1, 2, 3, 4) which are connected in series via gas ducts (7, 8, 9, 10), a heat treatment unit (11) which comprises at least one inlet opening (12) for introducing preheated raw meal from at least one preheater cyclone (4b) in a selected cyclone stage (4), where a gas outlet of said at least one preheater cyclone (4b) in the selected cyclone stage (4) in a vertical plane is located at a higher level than a gas/meal inlet of the preceding cyclone stage (3) as seen in the direction of movement of the cement raw meal. The plant is peculiar in that the selected cyclone stage comprises an additional cyclone which is placed in parallel to the other cyclone(s) in said cyclone stage and having in said vertical plane a gas outlet located at a lower level than said gas/material inlet of said preceding cyclone stage, and in that the gas ducts from the cyclones in the selected cyclone stage are merged into one single gas duct for conducting the mixed gases to said preceding cyclone stage. Hence, without affecting the installation height of the preheater, it will be possible to locate at least one of the cyclones of the selected cyclone stage at an arbitrary height relative to the other cyclone(s) in said cyclone stage, while simultaneously ensuring that raw meal from a preceding cyclone stage in an optimum way may be introduced into an upwardly flowing gas stream from said selected cyclone stage, i.e. in the gas duct from the additional cyclone. Preheated raw meal from the selected cyclone stage can therefore be introduced at any point into the heat treatment unit without any use of special lifting equipment. By proper mutually sizing of the cyclones of the selected cyclone stage, the amount of raw meal, which is lifted to a higher level, may be tailored the actual quantity needed for introduction at the higher located intake point. |
