Naming rule
Common rotary dryer models combine diameter and length. 0890 is read as φ0.8 × 9 m, meaning a drum 0.8 m in diameter and 9 m long; 1012 means φ1.0 × 12 m.
What diameter and length each affect
Drum diameter mainly affects the volume of material held at any moment and the cross-sectional air velocity; drum length mainly affects how long the material stays inside. A longer drum tumbles the material for longer and dries it more thoroughly, but takes up more space.
A first estimate
Materials with a high initial moisture content that need a longer dwell time usually call for a longer drum, while higher throughput demands a larger diameter. Both still have to be settled against the material properties and trial run results.
Custom sizes
Besides the common sizes, drums can be built to suit specific conditions. The same naming logic applies so that the numbers remain comparable.
References and Standards
- JB/T 6924—1998 干燥设备产品型号编制方法[S]. Beijing: China Machine Press, 1998. (in Chinese)
- JB/T 3266—2015 Rotary drum dryer[S]. Beijing: China Machine Press, 2015. (in Chinese)
- JB/T 10279—2013 Cylinder drier[S]. Beijing: China Machine Press, 2013. (in Chinese)
- Liu G W. Design Handbook of Drying Equipment[M]. Beijing: China Machine Press, 2009. (in Chinese)
- Krokida M, Marinos-Kouris D, Mujumdar A S. Rotary drying[M]//Mujumdar A S. Handbook of Industrial Drying. 4th ed. Boca Raton: CRC Press, 2014.