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

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Pal SZENTANNAI György PLÁVECZKY Csaba SÁNDOR Tibor SZŰCS Károly RENNER János ŐSZ

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 cannot be applied here.

Article Details

How to Cite
SZENTANNAI, Pal et al. A NEW DESIGN METHOD FOR FLUIDIZED BED CONVERSION OF LARGELY HETEROGENEOUS BINARY FUELS. Thermal Science, [S.l.], mar. 2017. ISSN 2334-7163. Available at: <http://thermal-science.tech/journal/index.php/thsci/article/view/2202>. Date accessed: 23 june 2017. doi: https://doi.org/10.2298/TSCI150903066S.
Section
Articles
Received 2017-03-03
Accepted 2017-03-13
Published 2017-03-13

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