Mathematical modeling of aroma compound recovery from natural sources using hollow fiber membrane contactors with small packing fraction

• Precise determination of concentration profile on the membrane walls.
• Study of velocity effect in membrane based solvent extraction in HFMC.
• Presenting a new correlation for the entrance length in a porous membrane.
• Higher efficiencies were observed by solvent n-hexane.

A numerical simulation was carried out in order to investigate aroma compounds recovery from aqueous phase using an organic solvent. A hollow-fiber membrane contactor with small packing fraction was selected to be used in the study. Momentum, continuity and mass transfer equations were solved simultaneously utilizing finite element method. The simulation results showed that solving the Navier–Stokes equations has significantly diminished average deviation about 55% compared to Happle’s velocity model. Simulation results revealed that mass transfer resistance increases along the contactor length in both tube and shell sides. It seems that it is due to the increasing thickness of the boundary layer. Enhancement of the solvent velocity could result in increasing mass transfer rate through the membrane. However, it reduced the extraction efficiency of aroma compounds. Moreover, recovery of 2-hexanal was higher than benzaldehyde due to its higher partition coefficient. Furthermore, n-hexane has higher extraction efficiency than miglyol because of lower Schmidt number.