THERMAL SCIENCE

International Scientific Journal

Pal Szentannai

,

György Pláveczky

,

Csaba Sándor

,

Tibor Szűcs

,

János Ősz

,

Károly Renner

A NEW DESIGN METHOD FOR FLUIDIZED BED CONVERSION OF LARGELY HETEROGENEOUS BINARY FUELS

ABSTRACT
Binary fuels of a fluidized bed combustor or gasifier are solids composed of two groups of particles. Their optimal handling in the same bed becomes rather difficult if their hydrodynamic properties differ by two orders of magnitude or more. Both of these fuel classes are directly fed into the reactor in most cases but the rather homogeneous fuel originally fed switches into a binary character inside the reactor in some others. A typical example of the latter case is the thermal utilization of rubber wastes. A novel design is proposed in the present paper by setting up a non-mixing, non-elutriated binary bed. Design criteria and procedure are formulated as well. One of the known calculation methods is proposed to be applied for assuring a segregated bed by means of choosing the bed components, geometry, and gas velocity conveniently. Cold model experiments are proposed to be applied for assuring no elutriation of the fine fuel particles and no sinking of the coarse fuel particles in the same time. A simple experiment is proposed for determining the common minimum fluidization velocity of the binary bed because known calculation methods can not be applied here.
KEYWORDS
Fluidized bed conversion, Binary fuel, Multi-component bed, Segregated bed, minimum fluidization velocity
PAPER SUBMITTED: 2015-09-03
PAPER REVISED: 2016-02-08
PAPER ACCEPTED: 2016-03-07
PUBLISHED ONLINE: 2016-04-09
DOI REFERENCE: https://doi.org/10.2298/TSCI150903066S
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2017, VOLUME 21, ISSUE Issue 2, PAGES [1105 - 1118]
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A new design method for fluidized bed conversion of largely heterogeneous binary fuels

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