Modeling study on the mass transfer of hollow fiber renewal liquid membrane: Effect of the hollow fiber module scale

Abstract

The effect of hollow fiber module scale on the mass transfer performance of hollow fiber renewal liquid membrane technique is studied experimentally and theoretically. Five scales of polypropylene hollow fiber membrane modules with same packing density and effective length are used for experiments. CuSO4 aqueous solution is used as feed phase, the organic solution of LIX984N in kerosene is used as liquid membrane phase, and H2SO4 is used as the stripping phase. The non-ideal flow status on the shell-side of the hollow fiber module is described by residence time distribution curves and quantitatively characterized by the Peclet number. Peclet number increases with the increase of L/d in hollow fiber module, and reaches its maximum value when L/d is 20, then decreases. The overall mass transfer coefficient is directly proportional to the Peclet number on the shell side in single-pass, recycling and cascade operation modes in the hollow fiber renewal liquid membrane process. A new mass transfer correlation is proposed to quantitatively describe the non-ideal flow on the shell-side of the hollow fiber module with Peclet number. Then, the corresponding mathematical model for hollow fiber renewal liquid membrane process is developed and the calculated results show good agreement with the experimental data.