S. Watano et al., AUTOMATION OF THE MANUFACTURING PROCESS OF COLD REMEDY GRANULES BY A TUMBLING FLUIDIZED-BED APPLYING THE FUZZY CONTROL METHOD, Chemical and Pharmaceutical Bulletin, 42(6), 1994, pp. 1302-1307
The automated manufacturing process of cold remedy granules using a tu
mbling fluidized bed will be described. Powdered materials, containing
salicylamide and acetaminophen as the main components and having been
used for the extrusion process previously, were granulated by a tumbl
ing fluidized bed. Effects of the operational variables on the propert
ies of granules were investigated,,which led to the conclusion that th
e exact control of bed height and moisture content was indispensable f
or continuously producing desired granules. The fuzzy control method b
ased on a linguistic algorithm of if-then rules was applied to the bed
height control, and programmed control of the moisture content was us
ed for the continuous operation from mixing, granulation to drying. By
means of the system developed, a series of operations could be conduc
ted automatically. Properties of the granules thus obtained were evalu
ated, and a comparison of the granules by this process to those by the
extrusion process used previously was conducted. It was concluded tha
t by means of the control system developed, desired granules which had
sharp particle size distribution, high yield, i.e., almost 100% of gr
anules, large apparent density and remarkably good flowability were ea
sily produced.