| 摘要 |
In a process for crystallising substances from their melt by atomising the melt and cooling the particles, undergoing a sinking motion, in a stream of cooling gas, it is provided, in order to obtain small grain sizes at large grain density and smooth spherical surface, that the cooling gas is fed in the region of the point at which the atomisation takes place, with a movement component in the direction of the sinking motion of the particles, so that the aerosol forming flows downwards in a helical movement, is taken off at the end of the sinking section and then separated into solid particles and carrier gas. For carrying out the process, an apparatus is proposed which consists of a crystallisation tower with an atomisation device arranged at the top, an aerosol take-off arranged at the bottom and a cooling gas feed which is arranged at the top of the crystallisation tower in the immediate vicinity of the atomisation device and is equipped for generating a downward-pointing helical flow.
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