THE NEW FALLING-FILM PLATE EVAPORATOR TECHNOLOGY IN HOHENAU SUGAR FACTORY - TECHNICAL DEVELOPMENT AND OPERATIONAL RESULTS

A reduction of the operating and maintenance costs, high process stabi lity, careful product handling and a high degree of thermal efficiency , while at the same time reducing investment costs, are the main corne rstones for the further development of evaporator technology. With the entry into service of the Balcke Durr falling-film plate evaporator i nstallation based on the falling-film plate evaporator technology at H ohenau sugar factory, for the first time the advantages of this new te chnology could be demonstrated when applied to an entire installation. In a Very small area, of 20,525 m(2), the plate evaporator heating su rfaces were installed in five effects. The minimum investment requirem ent predicted by Agrana for the entire project was about 28% in favour of the falling film plate evaporator versus a tube bundle falling fil m evaporator. Compared with the latest cutting edge technology - i.e. the tube bundle falling-film evaporator - it is actually possible to d emonstrate that the heating surface required can be reduced by 35% und er the same peripheral conditions with the Balcke-Durr technology base d on practical experiences obtained at Hohenau. A comparable tube bund le falling-film evaporator installation would have required an additio nal investment of around 62%. Due to the redevelopment of the evaporat or installation using falling-film plate evaporators and the periphera l thermal circuit, an energy saving of about 17% was achieved at Hohen au.