Etude de l'élimination de CO2 et H2S par absorption utilisant des solutions d'alcanolamines. Test du couplage de différentes théories de transfert de matière.

Abstract

Different techniques of depollution of gaseous emissions existent, among which the absorption by means of alkanolamine solutions, which has been retained in the present work, under the modelling aspect. The double film theory has been taken into consideration to quantify this transfer by means of the laws of Fick and Maxwell-Stefan. However, for the modelling of the column and the simulation of the contactor, two models, one of equilibrium and the other of non equilibrium, have been adopted. The general model is a sort of combination of different models such as that of kinetic which enables to quantify the source term in the continuity equation, the transfer model which gives the relation between the concentrations and the mass fluxes, and finally the thermodynamic model which enables the resolution of the physico-chemical problem. It can be concluded from the obtained results, that each of the two column models, presents certain advantages. The first, the non equilibrium model, is more general and enables the incorporation of different potentials, simultaneously, but with an inconvenient, its complexity. The equilibrium model is recommended for simulation cases where a certain system ideality prevails.