Ankush Nikam

Abstract of Masters Thesis:

DESIGN AND MODELING OF FLUID BED DRYERS

Fluidized bed dryers are used extensively for the drying of wet particulates and granular materials that can be easily fluidized and even slurries, pastes, and suspensions that can be fluidized in beds of inert solids. They are commonly used in processing of chemicals, foodstuffs, biomaterials, pharmaceuticals in powder or agglomerated form. Fluidized bed operation has important advantages such as good solid mixing, high rates of heat and mass transfer, high thermal efficiency, low maintenance cost and ease of operation. For drying of powders in the particle size range 50 to 2000 m, fluidized bed compete successfully with other more traditional dryer types, e.g., rotary, tunnel, conveyor, continuous tray  etc.
Drying is an energy intensive operation consuming 9–25% of national industrial energy in the developed countries. It appears to be a complicated process involving simultaneous, coupled heat and mass transfer phenomena, which occur inside the object being dried. The temperature and moisture distributions inside the moist solids during drying are of great importance in the drying industry in order to provide better design and performance analysis of the drying process, the use of numerical simulation has become an essential tool in this regard.

The objective of the proposed work was to develop and simulate the process of heat, mass and momentum transfer model taken into consideration of with and without shrinkage behavior in a gas-solid fluid bed dryer, particularly in the falling rate period. Also the objective of the proposed work was to develop and simulate the mathematical model of a plug flow fluidized bed dryer that could be used for designing a large scale industrial plug flow fluidized bed dryers using lab scale batch FBD data.