Abildskov, Jens2; Azquierdo-Gil, M.A.4; Jonsson, Gunnar Eigil2
1 Computer Aided Process Engineering Center, Department of Chemical and Biochemical Engineering, Technical University of Denmark2 Department of Chemical and Biochemical Engineering, Technical University of Denmark3 Membrane Technology group, Department of Chemical and Biochemical Engineering, Technical University of Denmark4 unknown
Vacuum membrane distillation (VMD) has been studied as a separation process to remove volatile organic compounds from aqueous streams. A vapour pressure difference across a microporous hydrophobic membrane is the driving force for the mass transport through the membrane pores (this transport takes place in vapour phase). The vapour pressure difference is obtained in VMD processes by applying a vacuum on one side of the membrane. The membrane acts as a mere support for the liquid-vapour equilibrium. The evaporation of the liquid stream takes place on the feed side of the membrane, and the condensation on the permeate side of the membrane. The paper focus on aroma stripping using VMD; factors influencing flux and separation performance using selected model aroma compounds have been studied. Mainly the following parameters have been examined-aroma compounds: activity coefficient/vapour pressure values; membrane type: PTFE/PP/PVDF; feed flow rate; feed temperature. A comparison is made between different thermodynamic models for calculating the vapour-liquid equilibrium at the membrane/pore interface. (C) 2004 Elsevier B.V. All rights reserved.
Journal of Membrane Science, 2004, Vol 239, Issue 2, p. 227-241