ABSTRACT
Typical operating parameters for rotary dryers
used for coal drying are given in Table 43.1.
The heat consumption in such dryers amounts to
about 3700kJ/kgH2O.Thedrying time is about 15 to40
min at a holdup fraction of 0.15 to 0.25. The gas velocity
at the dryer outlet should not bemore than 2 to 3m/s for
the drying of fine coals derived from washing and not
more than 0.5 to 1m/s for the postflotation concentrates
to avoid excessive carryover of coal. The dimensions of
the rotary dryer are determined based on the drying rate
per unit volume, which is given in Table 43.1.
