Print ISSN: 1681-6900

Online ISSN: 2412-0758

Author : A. Alwasiti, Asawer

The Effect of Solid on the Homogenous- Heterogeneous Transition Region in Baffled and Unbaffled Bubble Column with Non-Newtonian Liquid

Asawer A. Alwasiti; Farah T. Alsudany; Shrooq T. Alhemeri

Engineering and Technology Journal, 2010, Volume 28, Issue 23, Pages 6732-6749

This research shows a comprehensive study on the effect of solid loading
and non-Newtonian liquid on the hydrodynamic parameter of gas holdup as well
as the critical values of gas holdup and gas velocity of transition zone from
homogenous to heterogeneous region in both baffled and unbaffled babble
The experiments were carried out using column of 15cm inside diameter and 2m
height with aspect ratio (L/D=4.5) using perforated plate gas sparger 54 holes with
size equal to 1mm diameter and with free area of holes to cross sectional area of
column 0.24.
The three phase system consists of air-non Newtonian liquid of polyacrilamined
(PAA) –solid of alumina particles. The measured values of gas holdup and
transition points of gas holdup and gas velocity were compared with different
values of PAA concentration (0, 0.01, 0.05 and 0.1)wt% and four values of solid
loading (0, 3, 5 and 11)wt% in baffled and unbaffled column.
The results show that the transition values of gas holdup and gas velocity
decreased with increasing of PAA concentration under constant values of
Newtonian liquid while they dis approved with non-Newtonian liquid.
The solid loading shows an unstable influence of decreasing and increasing of the
critical values in all PAA concentration and in both baffled and unbaffled column.
First, these values decreased when solid loading in the range (0-3)wt% then they
increased with increasing of solid loading from 3wt% to 11wt%.