Abstract: The enhancement separation efficiency of yeast/MgSO4 mixtures via gas-liquid two-phase flow is evaluated in a DK2540F spiral nanofiltration membrane module.Investigation is performed to determine the effects of different conditions on permeate flux,rejection and permeate flux increase rate of the spiral nanofiltration membrane.The experimental results indicate that two-phase flow can obviously enhance the separation effect of yeast/MgSO4 mixture in spiral nanofiltration membranes.The permeate flux of yeast suspension is obviously enhanced by higher trans-membrane pressure and larger gas-liquid ratio,with a growth of 15.2%.Meanwhile,better enhancement effect for separating yeast-MgSO4 mixture can be achieved under lower trans-membrane pressure and higher gas-liquid ratio,and permeate flux can lift by 40% or more.Additionally,gas-liquid two-phase flow affect scarcely the rejection of MgSO4 that remains mostly between 90% and 94%.
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