INTEC   05402
INSTITUTO DE DESARROLLO TECNOLOGICO PARA LA INDUSTRIA QUIMICA
Unidad Ejecutora - UE
artículos
Título:
Flow Study and Wetting Efficiency of a Perforated-Plate Tray Distributor in a Trickle Bed Reactor
Autor/es:
RAMAJO, DAMIAN; MARQUEZ DAMIAN, SANTIAGO ; RAVICULE MARCELA; MONSALVO MARIA; STORTI MARIO; NIGRO NORBERTO
Revista:
INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING
Editorial:
BERKELEY ELECTRONIC PRESS
Referencias:
Año: 2010 vol. 8 p. 1 - 20
ISSN:
1542-6580
Resumen:
In this work, a computational fluid dynamics analysis (CFD)
employing the Eulerian two-fluid model was carried out with the aim to
understand the distribution process and to determine the wetting
efficiency of the primary tray distributor (perforated plate) of a
trickle bed reactor (TBR) under several operating conditions. The
overall inlet geometry was considered, and the small holes of the
perforated plate were modeled by sinks (drains) and sources, employing
CFD and experimental models to obtain the hole discharge flow
coefficients. The influence of the ceramic-ball bed above the catalyst
bed was considered by a suitable correlation to estimate liquid
distribution inside it.
Results showed that because of the scarce liquid sloshing above the
tray, little difference on liquid flow rate through the tray holes was
found. Due to the really low inlet mass flow rate of gas, it has
negligible influence on liquid behavior, which drops through holes
slowly without spraying. Thus, the ceramic-ball bed above the catalyst
bed is exclusively wetted in a small area under the tray holes.
Although the ceramic-ball bed improves liquid distribution, which
guarantees a minimum liquid volume fraction at all places, significant
differences on the liquid mass flow rate across the top of the catalyst
bed were found. Additional causes of low efficiency in TBR like the
well-known fouling vulnerability of perforated-plate trays and
unevenness were analyzed. For the first, two simple modifications were
proposed to improve tray performance: reducing the amount of gas
chimneys to only one and adding additional drip points and replacing
the tray holes by short risers in order to avoid plugging.