S. Mohammadighavam, B. Kløve
University of Oulu, Department of Process and Environmental Engineering ,Oulu, Finland
After rapid mixing of waste water and coagulant, an effective slow mixing during a reasonable retention time will cause to grow the size of flocs up which will settle out easily. Around-the-end hydraulic mixer with barriers is one of the efficient facilities that have been used in water treatment plants for this purpose. A uniform velocity gradient (G) is needed to achieve efficient mixing and ...
C. Bayer, S. Stiefel, M. Follmann, and T. Melin
AVT Chemical Process Engineering, RWTH Aachen University, Aachen, Germany
Reactive extraction of organic acids from an aqueous solution to an alkaline stripping fluid is based on a selective barrier allowing permeation of non-polar molecules, which subsequently react with the stripping agent. The shift from the organic acid to its base induced by the chemical equilibrium enhances mass transfer inside the membrane’s porous substructure. A model of the porous layer ...
D. Dalle Nogare and P. Canu
Department of Chemical Engineering Principles and Practice, University of Padova, Padova, Italy
This work investigates the effects of boundary conditions on the species profiles in heterogeneous catalysis, with low Péclet systems. Hydrogen combustion in Helium was chosen because of the high diffusivities. Furthermore, already at T=300°C over a Pt catalyst, kinetics is very fast and the composition gradients at the inlet extremely steep. The issue is analyzed with 1D models, ...
M. Weber, M. Reed
Yale University, New Haven, CT, USA
Arrays of vertical pillars, Micro Purification Chips, have been widely used for analyte capture from liquid samples [Henderson et. al, 2006], [Toner et. al, 2007], [Stern et. al, 2010]. However exact understanding of the capture efficiency mechanisms has not been previously explained. Here we present a model in COMSOL Multiphysics® which calculates analyte capture efficiency based on initial ...
G.M. Mule, A.A. Kulkarni
CSIR - National Chemical Laboratory, Pune, Maharashtra, India
Stirred tanks are widely used in the pharmaceuticals, chemical and paint industries for variety of operations. The fractal impeller is an impeller having a novel design, developed by CSIR-National Chemical Laboratory, Pune, India. The power number of fractal impeller is relatively lower than the conventional impellers. The mixing performance is also relatively better than the conventional ...
Dynamic adsorption with FEMLAB, modeling breakthrough curves of gaseous pollutants through activated carbon beds
Joly, A.1, Volpert, V.1, Perrard, A.2
1 Institut Camille Jordan (ICJ), CNRS UMR 5208, Mathématiques, Université Claude Bernard Lyon, Villeurbanne Cedex, France
2 Institut de Recherches sur la Catalyse, CNRS UPR 5401, Villeurbanne Cedex, France.
The purpose of this presentation is to expose how to apply FEMLAB to model the dynamic adsorption through adsorbent columns and to use the results of the numerical simulations to interpret the experiments. The mathematical formulation of the phenomena leads to a system of two partial differential equations (mass balance and adsorption rate), which can be solved in most cases only after ...
T. Williams1, K. Gazda1, A. Kindler2, Y. Huang2, D. Karner3, J. Read4
1GreenMountain Engineering, San Fransisco, CA, USA
2Jet Propulsion Laboratory, California Institute of Technology, CA, USA
3ETEC, Phoenix, AZ, USA
4ECOtality, Scottsdale, AZ, USA
Energy storage is an increasingly important area of research both for use in alternative transportation and to enable the widespread use of intermittent energy sources such as wind and solar energy. This paper presents a multiphysics model of a novel technology for hydrogen storage, in which hydrogen is stored in a packed bed of metal hydride and released by application of steam through a number ...
Modelling of Reactive Non-Isothermal Mixture Flow and its Simulation in COMSOL Multiphysics® Software - new
V. Orava[1,2], O. Soucek, P. Cedula
Charles University in Prague, Prague, Czech Republic
Zurich University of Applied Sciences, Winterthur, Switzerland
I introduce a model of fluidized reactor which, in presence of heterogeneous platinum-based catalyst, decomposes liquid formic acid producing gaseous mixture of carbon dioxide and hydrogen as the product. I treat the physical system as a (Class II) mixture of four constituents - namely formic acid (FA), Platinum micro-pellets (Pt), carbon dioxide (CO_2) and hydrogen (H_2) - which can be, without ...
Molin, P., Ferret, E., Gervais, P.
Laboratoire GPAB, ENSBANA, Dijon, France
A 3D model for growth of filamentous fungi on solid substrate, based on microscopic observations was developed and tested on macroscopic experimental data. Comparisons with previous models were performed. The specificity of solid substrate growth was taken into account in the model equations. Interest for FEMLAB users is the difficulties we had to define 3D complex structures, like polyhedra.
Analysis of Heat, Mass Transport, and Momentum Transport Effects in Complex Catalyst Shapes for Gas-Phase Heterogeneous Reactions Using COMSOL Multiphysics
A. Nagaraj, and P. Mills
Department of Electrical Engineering and Computer Science, Texas A&M University, Kingsville, TX, USA
Department of Chemical and Natural Gas Engineering, Texas A&M University, Kingsville, TX, USA
The global demand for sulfuric acid has been forecast to grow at an average of 2.6% per year from 2005 – 2010. The primary objective of this work is to analyze the performance of various heterogeneous catalyst shapes that have been proposed for the oxidation of SO2 to SO3 used in the manufacture of sulfuric acid. COMSOL Multiphysics provides a powerful numerical platform for simulation of ...