Desalination sea water by indirect freezing : thermodynamics aspect and influence of operating conditions
type: Dataset
contact point: Organization
  fn: CCSD
keyword: spiotherengineering-sciences-physicsother
keyword: modele-thermodynamique
keyword: infoeu-reposemanticsdoctoralthesis
keyword: physical-property
keyword: eau-de-mer
keyword: cristallisation-en-milieu-fondu
keyword: drinking-water
keyword: crystallization-of-molten-medium
keyword: thermodynamic-model
keyword: propriete-physique
keyword: eau-potable
keyword: sweating
keyword: seawater
keyword: ressuage
keyword: dessalement
keyword: desalination
keyword: theses
landing page: https://theses.hal.science/tel-00958034
description: The work aims to develop a process for freezing desalination of seawater on cold walls. The thermodynamic study has quantified the effect of composition and of salinity on the freezing temperature and the precipitation temperature of Na2SO4,10 H2O. The results are well described by the calculation code Frezchem, derived from the model of Pitzer. The experiments were performed with water/NaCl solutions of different concentrations and with samples of sea water from Nice, Rabat and Marseille. The pilot crystallizer consists of a cooled tube immersed in a cylindrical double jacketed tank containing water to be treated. The complete process of desalination is conducted in two steps: the freezing step, leading to the crystallization of the ice layer and the sweating step, which consists of purifying in depth the ice layer by melting the impure zones. A camera films the ice and provides the growth kinetics of the layer. Freezing was performed in a stagnant solution to a stirred solution or by injecting air. It is conducted by applying two cooling ramps, respectively in the tube and the double jacket that may or may not be identical. Tests have shown the need to seed the ice on the tube and fine-tune the initial temperature of the cooling ramp. The systematic study of the influence of operating parameters has highlighted the important role of the cooling ramp and salinity of the solution on the purity of the ice produced. In the absence of stirring, the temperature of the double jacket also has a noticeable effect on the purity of the ice due to temperature gradients, and consequently, convection currents that may result in the solution. Steady stirring, the solution seems to be at all times in equilibrium with ice. Same final salinity of the ice can be obtained with ramps cooling much faster than static. Whatever the performance of the freezing, the sweating is then necessary to meet the standard for drinking water. The search for optimum operating conditions has reduced t…
identifier: NNT: 2011LYO10274
issued: 2026-05-06T01:23:47.323748
language: fr
modified: 2026-05-06T01:23:47.323753

Desalination sea water by indirect freezing : thermodynamics aspect and influence of operating conditions
type: Distribution
access URL: https://theses.hal.science/tel-00958034
format: HTML
issued: 2026-05-06T01:23:47.330975
modified: 2026-05-06T01:23:47.297146

test_moissonnage_selune
type: Agent