|
 |
Heat Exchanger Fouling and Cleaning VII
July 1-6, 2007 - Tomar, Portugal
| Editors: |
Hans Müller-Steinhagen, Institute of Technical Thermodynamics, German Aerospace Centre (DLR)
and Institute for Thermodynamics and Thermal Engineering, University of Stuttgart, Germany
M. Reza Malayeri, University of Stuttgart, Germany
A. Paul Watkinson, The University of British Columbia, Canada |
The articles for these proceedings are peer-reviewed.
|
<Previous article
|
Next article>
|
FOULING MITIGATION WITH SYNTHETIC FIBRES IN A CASO4 SUPERSATURATED SOLUTION
M. Rost, Institute of Thermodynamics and Thermal Engineering, University of Stuttgart, Germany
G. G. Duffy, Department of Chemical and Materials Engineering, University of Auckland, New Zealand
ABSTRACT:
Wood pulp fibre suspensions and model synthetic fibre
suspensions have been shown previously to mitigate
effectively calcium sulphate fouling in heat exchangers.
Fibre flexibility was found to be a decisive fibre property in
fouling mitigation. Adding fibres to a fouling fluid is
environmentally benign and can be applied during operation
without shutting down the heat exchanger. Because polymer
fibres are more robust in a hostile environment, further
work was initiated with two types of rayon fibre and one
acrylic fibre of the same fibre length.
Experiments were performed at both constant and
varying fibre volume concentrations. The more flexible
rayon fibres in suspension produced lower ultimate-fouling
resistance values than the stiffer acrylic fibres. Fibres were
embedded in the fouling layer and it is believed that this
mechanism contributed to the overall fouling resistance and
was a counterpart to the positive effects of fibres mitigating
fouling. The more flexible fibres momentarily form viscoelastic
bundles that can ‘absorb’ hydrodynamic shear forces,
modify the turbulent stresses, and lower the fouling matter
removal rate. Stiff fibres embedded in the deposit protrude
into the bulk flow and entrap more fibres as they are less
likely to deflect, bend, and be flattened by the shear stresses
near the wall.
M. Rost and G. G. Duffy, "FOULING MITIGATION WITH SYNTHETIC FIBRES IN A CASO4 SUPERSATURATED SOLUTION" in "Heat Exchanger Fouling and Cleaning VII", Hans Müller-Steinhagen, Institute of Technical Thermodynamics, German Aerospace Centre (DLR)
and Institute for Thermodynamics and Thermal Engineering, University of Stuttgart, Germany
M. Reza Malayeri, University of Stuttgart, Germany
A. Paul Watkinson, The University of British Columbia, Canada
Eds, ECI
Symposium Series, Volume RP5 (2007). http://services.bepress.com/eci/heatexchanger2007/26
|
|
|
|
 |
|
|
|
|
|
|
|
