The residence time distribution (RTD) of solids in spiral fluidised beds was experimentally investigated, covering as variables the flow rates of the phases, the particle characteristics and the column and plate geometries. The RTD was adequately described by the Fickian diffusion model, indicating that particle dispersion can be predicted from a knowledge of particle diffusivity. Correlations for the particle mean residence times and the particle diffusivity are presented. © 1989.

Y. Pydisetty

K. Krishnaiah

Y. B.G. Varma

CHEMICAL EQUIPMENT--FLUIDIZED BEDS

Diffusion

Mathematical models

axial dispersion

FICKIAN DIFFUSION MODEL

GAS-SOLID FLUIDIZATION

Residence time distribution

SPIRAL FLUIDIZED BEDS

Powders

Axial

DISPERSION

Fluidized Beds-Gas/Solid

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Axial dispersion of solids in spiral fluidised beds

Powder Technology

Solids are dried in batch and in continuous fluidized beds corresponding to cross-flow and countercurrent flow of phases covering a wide range in drying conditions. Materials that essentially dry with constant drying rate and then give a falling drying rate approximately linear with respect to solids moisture content (sand) as well as those with an extensive falling rate period with the subsequent falling rate being a curve with respect to the moisture content (mustard, ragi, poppy seeds) are chosen for the study. The performance of the continuous fluidized bed driers is compared with that of batch fluidized bed driers; the performance is predicted using batch kinetics, the residence time distribution of solids, and the contact efficiency between the phases. © 1995, American Chemical Society. All rights reserved.

Industrial and Engineering Chemistry Research

Drying of Solids in Fluidized Beds

A kinetic model is developed for the drying of solids in fluidized beds, assuming a falling rate period following a constant rate period. Experimental data obtained using batch and continuous single and spiral fluidized beds are satisfactorily matched with the assumed drying kinetics and the residence time distribution of solids appropriate for the type of dryer. Copyright © 1990 American Institute of Chemical Engineers

AIChE Journal

Fluidized bed drying of solids

Correlations for the pressure drop, solids concentration and mean holding time of the solids in multistage fluidisation have been presented based on the experimental data of the present study and that available in literature covering a wide range in process variables. Copyright © 1982 Canadian Society for Chemical Engineering

The Canadian Journal of Chemical Engineering

Pressure drop, solids concentration and mean holding time in multistage fluidisation

The residence time distribution of the solids in multistage fluidisation, wherein downcomers for transferring the solids from stage to stage are provided to the horizontal perforated plates, is experimentally investigated covering a wide range in process variables using flat, baffle and spiral plates developed in the study. The RTD data is modelled using (i) the multiple parameter model, (ii) the diffusional mixing model and (iii) the fractional tank extension model when it is noted that over certain conditions of operation both spiral and baffle plates indicate near piston-flow for the solids without hampering the fluidisation characteristics. © 1982.

Chemical Engineering Science

Residence time distribution of solids in multistage fluidisation

The influence of operating variables on the residence time distribution for material transport in a continuous rotary drum

The Modern Language Review

Neoplatonic Allegory in Calderon's "Las Fortunas de Andromeda y Perseo"

Wear

Inst. mech. engrs. tribology convention 1968

Journal	Powder Technology
ISSN	00325910
Open Access	No