Two phase fluidization of coarse materials in a tapered fluidized bed

Abstract

The object of this work is to study onthe tapered bed fluidization in tapered bed& to correlate the relation between pressure drop and volume flow rates. The quality and quantity of mixing and segregation of heterogenous materials are analysed. To study the characteristics of tapered beds , several experiments have been carried out with different tapered angles of the bed , with regular as well as irregular particles of different sizes and densi- ties. The tapered angles of the beds have been found to affect the characteristics of the bed. Detailed visual observations of fluid and Particle behavior and measurements of the pressure drops have led to the identification of five flow regimes.Tapered fluidized beds are widely used in industrial operations to fluidize a wide range of particle sizes , and are thought to induce relatively strong particle mixing. Like their straight – sided counter parts , tapered fluidized beds are often considered as a homogenous emulsion phase thr- ough which bubble propagates. However it has been shown that gas flow through dense Particles is heterogenous , generating a central fluidized core and unfluidized peripheral regions. The time scale for particle turnover in the central fluidized region is much shorter than that of particles captured within the peripheral regions.