Skip to Main content Skip to Navigation
Theses

Hydrodynamique dans les circuits de refroidissement industriels : influence sur les phénomènes d’encrassement, caractérisation et modélisation

Abstract : Industrial cooling circuits with wet cooling towers use raw water (from rivers or sea) in order to remove residual heat from industrial processes. Raw water contains suspended matters, chemical and biological species. This water is heated in the circuit condenser and evaporation induces species concentration. That’s why different kind of fouling can be observed in cooling circuits: particulate fouling, chemical reaction fouling and biofouling. Hydrodynamics in the different parts of the circuit strongly influence fouling deposition. This report aims to provide a complete characterization of the cooling circuit hydrodynamics and to model all the fouling phenomena. The Compartmental Modelling approach has been selected doing a critical review of the modelling approaches available in Chemical Engineering. Compartmental modeling is a multi-scale (local and system) approach dividing the studied system into spatially representative hydrodynamic compartments network. Different physico-chemical models can be patched into the compartmental model. To create the compartmental model, it was necessary to characterize the flow characteristics in the different parts of the circuit: condenser tubes, concrete pipes, cooling tower packing and cold water basin. A pilot-scale cooling tower experimental setup has been built to visualize and measure water flow into packing. Mono-phase and multi-phase (Volume of Fluid with solid/liquid contact angle model) Computational Fluid Dynamics simulations have been performed to study hydrodynamics in packing and in cold water basin. All the required information about hydrodynamics in the circuit have been obtained such as velocity, shear stress, phase fraction and water film thickness. The method processed in this work can also be used to characterize different industrial packing. A biofouling growth model has been created considering transport and transfer phenomena limitations into the biofilm and into the liquid bulk. The model has been built taking into account shear stress as main hydrodynamic parameter using experimental data from literature with different geometries and different operating conditions. Finally, the compartment model has been developed using data from hydrodynamic characterization and the biofouling model. This model can simulate and predict biofilm deposition in the different parts of the cooling circuit. The created compartmental model is a suitable approach to study the influence of hydrodynamics behavior on fouling in cooling circuits.
Complete list of metadata

https://hal.univ-lorraine.fr/tel-03176226
Contributor : Thèses Ul <>
Submitted on : Monday, March 22, 2021 - 11:17:46 AM
Last modification on : Monday, March 29, 2021 - 4:07:22 PM

File

DDOC_T_2020_0179_JOURDAN.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-03176226, version 1

Collections

Citation

Nicolas Jourdan. Hydrodynamique dans les circuits de refroidissement industriels : influence sur les phénomènes d’encrassement, caractérisation et modélisation. Génie des procédés. Université de Lorraine, 2020. Français. ⟨NNT : 2020LORR0179⟩. ⟨tel-03176226⟩

Share

Metrics

Record views

42

Files downloads

26