Gas-liquid mass transfer in a circulating jet-loop nitrifying MBR

in Chemical Engineering Science (2005), 60(22 Sp. Iss. SI), 6346-6353

Based on airlift configuration, a novel circulating jet-loop submerged membrane bioreactor (JLMBR) adapted to ammonium partial oxidation has been developed. Membrane technology and combined air and water ... [more ▼]

Based on airlift configuration, a novel circulating jet-loop submerged membrane bioreactor (JLMBR) adapted to ammonium partial oxidation has been developed. Membrane technology and combined air and water forced circulation are adopted to obtain a high biomass retention time and to achieve a separate control of mixing and aeration. This study is intended to determine how gas-liquid mass transfer is affected by operating conditions. In a first approximation, liquid was assumed to be perfectly mixed. A classical non-steady state clean water test, known as the "gas out-gas in" method, was used to determine the gas-liquid mass transfer coefficient k(L)a. Air and recirculated liquid superficial velocities were gradually increased from 0.013 to 0.019m s(-1) and 0.0056 to 0.011 m s(-1), respectively. Subsequently, the gas-liquid mass transfer coefficient kLa varied from 0.01 to 0.02 s(-1). It appears to be influenced by the combined action of air and recirculated liquid flowrates in the range 0.72-1.03N m(3) h(-1) and 0.30-0.58 m(3) h(-1), respectively, for air and liquid. Correlations are proposed to describe this double influence. Experiments were performed on tap water and a culture medium used for the autotrophic growth of nitrifying bacteria, respectively. Oxygen transfer appeared to be not significantly affected by the mineral salt (0.48 g 1(-1)) encountered in this medium. (c) 2005 Elsevier Ltd. All rights reserved. [less ▲]

Imaging of liquid distribution in reactive distillation packings with a new high-energy x-ray tomograph

in Measurement Science & Technology (2005), 16(11), 2213-2220

We describe a new, high-energy (420 kV), large-scale (0.45 m in diameter, 4 m in height) x-ray tomograph developed to investigate gas and liquid flow through fixed bed like absorption, distillation and ... [more ▼]

We describe a new, high-energy (420 kV), large-scale (0.45 m in diameter, 4 m in height) x-ray tomograph developed to investigate gas and liquid flow through fixed bed like absorption, distillation and reactive distillation columns. The first results obtained with this set-up on test objects (physical phantoms), such as a cylindrical container filled with water or a large diameter structured metallic packing, validate the technique as a quantitative tool for geometrical measurements. Very detailed two-dimensional (21)) and three-dimensional (3D) images of a 0.09 m diameter KATAPAK-SP 12, a reactive distillation packing, are presented. Quantitative information relative to liquid hold-up distribution may be obtained from tomographic imaging performed on an irrigated column packed with this element. [less ▲]

Étude de la texture poreuse d'un matériau polymère cellulaire utilisé en ingénierie tissulaire par microtomographie à rayons X

Poster (2005, October)

Integrated adsorbent and process characterization. Application to air separation PSA processes

Conference (2005)

High energy, high resolution x-ray tomography applied to catalytic distillation packings

Conference (2005)

3D imaging of reactive distillation packings with a new high energy x-ray tomograph

in Jong, A.; Takei, M.; William, R. A. (Eds.) et al Proceedings of 4th World Congress in Industrial Process Tomography (WCIPT4), Aizu, Japan, 5-8 septembre 2005 (2005)

Possibilities and limits of application of electrical resistance tomography in hydrodynamics of bubble columns

in Canadian Journal of Chemical Engineering (2005), 83(1), 4-10

Knowing the hydrodynamic regime in which is working a bubble column is of great importance because the regime affects strongly the mass transfer between the phases. To this end, we examine the ... [more ▼]

Knowing the hydrodynamic regime in which is working a bubble column is of great importance because the regime affects strongly the mass transfer between the phases. To this end, we examine the potentialities of an Electrical Resistance Tomography (ERT) device. We analyse cross correlation of electrode pair measurements, of neighbouring pixels and power spectra of averaged pixels within a single plane as well as cross correlations of averaged pixels between two planes, without finding a clear signature of the churn turbulent flow. Variable gas flow rate inputs are used to determine the time resolution of the ERT. [less ▲]

Computed Tomography at the University of Liège – Chemical Engineering Laboratory

Scientific conference (2004, August)

Electrical tomography investigation in bubble columns

Scientific conference (2004, August)

Flow visualisation of non-Newtonian fluids in a stirred tank using Particle Image Velocimetry : evolution with time

Conference (2004)