During the drying experiments the temperature of the
dryer was first raised to the set temperature and the
steady conditions maintained for at least 30 min before
inserting the samples. The sample was then loosely
spread on a wire-mesh tray to the required depth raging
from 10 to 50 mm. The mass of sample was measured
using a digital balance, measuring to an accuracy of
0.001 g, immediately before inserting it into the dryer.
Thereafter the mass was periodically taken by briefly
removing the sample from the dryer. The velocity of
the air during drying was set at 1 m/s and the sample