Abstract of "A FLUIDIZED BED DRIER FOR SUSPENSIONS AND PASTES"

DOI: 10.1615/ICHMT.2000.TherSieProcVol2.750
159 pages

Zeljko B. Grbavcic
Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, POB 494 11000 Belgrade, Yugoslavia

Zorana Lj. Arsenijevic
Institute for Chemistry, Technology and Metallurgy, Njegoševa 12, 11000 Belgrade, Yugoslavia

Sinopsis

A fluid bed dryer with inert particles was used for drying of suspensions. The effects of the operating conditions on dryer throughput and product quality were investigated. Experiments were performed in a cylindrical column 215 mm in diameter and 800 mm in height with glass spheres 0.925 mm in diameter as fluidizing media. The fungicides and pesticides (Cineb, Ciram, Propineb, Mangoceb, Copper-hydroxide, Copper oxy-chloride, Copper oxy-sulphate), other inorganic compounds (Calcium carbonate, Calcium sulphate, Cobalt carbonate) and complex compound (Organo-bentonite) and pure water were used as feeding materials. With respect to the main efficiency criteria, i.e. specific water evaporation rate, specific heat consumption and specific air consumption the fluid bed dryer with inert particles represents a very attractive alternative to the other drying technologies. High drying efficiency results from the large contact area and from the large temperature difference between inlet and exit air. The rapid mixing of particles, due to the aggregative fluidization, leads to the nearly isothermal conditions throughout the bed. In our experiments were successfully treated suspensions and very dense pastes. Suspension and product hold-up in the bed varies between 6 and 8% by mass and the product with the same particle size as raw material is obtained.