PASTELIKE MATERIALS DRYING IN ROTARY DRYER WITH INERT BED

摘要

The rotary dryer with inert bed is a novel pastelike materials drying device. This paperrnpresents the results of drying tests using a rotary dryer with a bed of inert particles. Thernperformance of the equipment in the drying of two pastelike materials, namely molassesrnand maltodextrin with dextrose equivalent (DE) of 10, is evaluated. For the molassesrndrying, a mixture of smooth-faced spheres made of porcelain and stainless steel (41 mmrnand 30 mm diameter, respectively) was employed. For the maltodextrin drying, onlyrnrough, stainless steel spheres (diameter 25 mm) were used as a inert bed. The dryerrnrotation was kept at 18 rpm and the drying air flow rate ranged from 2.5 to 5.4 kg/min.rnThe drying was carried out during 20 to 60 minutes between each molasses feedingrn(intermittent operation). The pastelike materials were characterized under the moisturernof 32.7% wb (molasses) and of 41% wb (maltodextrin) between 25 and 70oC.