Medical Hydrology and Balneology: Environmental Aspects

Study of a cosmetologic salt production process
Coussine C (1) , Cezac P (2) , Serin J (2) , Contamine F (2) , Reneaume J (2) ,
Dubourg K (1) , Cambar J (1)
(1) Institut du thermalisme, Université Bordeaux Segalen, Dax, France
(2) Laboratoire de Thermique, Energétique et Procédés (LaTEP), Université de Pau et
des Pays de l’Adour, Pau, France
charlotte.coussine@univ-pau.fr
Introduction and Objectives
The aim of this study is to control the production of salts and salt waters concentrated
in magnesium using salt spring water as raw material. The process is based
on sustainable development principles. Indeed, the raw material is exclusively a
natural resource (salt spring water like thermal water of Salies-de-Béarn) and the
by-product of process can be directly used as concentrated thermal water in spas.
Besides, renewable energy like solar energy can be used in this process.
Materials and Methods
To study the salt production process, we developped a dynamic model based on
a thermodynamic approach that can accurately predict the resulting phase distribution
and phase composition in salt water. The model is based on a thermodynamic
description of the physical-chemical phenomena occurring in a Gas-Liquid-Solid
electrolytic system. Two types of equilibriums are considered: phase equilibrium
and chemical reaction equilibrium. So the equations used are: the two types of
equilibrium, the partial mass balance and the electroneutrality. The non-ideality of
solution is described by Pitzer’s model (to calculate the activity coefficients). Precipitation
of different salts is automatically considered by the integrator as event
using the thermodynamic solubility constants.
Results
Experimental data are compared with the calculated values in order to validate
the use of the model for salt waters applications. We experiment the process with
artificial salt water like raw material. The lab-pilot is a series of two water jacketed
vessels under agitation with a temperature and pressure control. A filtration system
is placed between the two vessels in order to separate the solid phases and the
aqueous solution. The concentrations of species in the saturated solution (clear
supernatant solution) are determined by using ion chromatography.
Conclusions
The developed model is a suitable tool for the simulation of salt water behavior.
Balnea
2012, núm. 6, 423-424
423
ISBN: 978-84-669-1887-0
978-84-669-3482-4