Modern concepts for drying and cooling of crystal sugar, developments and their technical application; Hartmut Hafemann and Burkhard Bartels, Braunschweigische Maschinenbauanstalt (BMA) AG

摘要

Drying and cooling as the last and final step of refined sugar production is of utmost importance. Modern concepts for drying and cooling of refined sugar are aimed to produce a final product which releases its remaining moisture in a reasonable period of time without caking. In general, the temperature at which sugar is loaded into bulk transportation means has been found to be a major factor of quality and stability. Certain moisture contents are acceptable if the loading temperature is adjusted properly. Modern equipment and technology are described to achieve the proper condition of final sugar at a minimum use of investment, space and power. Sugar drying normally takes place in rotary units. The development of those from conventional to state-of-the-art design is described. Cooling itself can either be done in the rear part of a combined rotary dryer/cooler with or without cooling air conditioning. Or, where intensive cooling is required, a separate fluidized bed cooler is attached downstream of the rotary dryer. Such cooler can also have cooling air conditioning in addition to contact cooling with integrated cooling surfaces. Finally, an outlook is given to the latest development in this field which is a vertical design of a fluidized bed sugar conditioner.