脉冲流强化膜蒸馏高浓度盐水的研究

Research on membrane distillation of high-concentration saline solution with pulsatile flow

采用聚偏氟乙烯(PVDF)中空纤维膜组件,探究了脉冲时长与脉冲频率对脉冲流强化气扫式膜蒸馏高浓度盐水过程性能的影响.研究结果表明,当进料流量为30L/h,进料温度为323K,冷凝液温度为283 K,气扫速率为0.74 m^3/h时,在最佳的脉冲长度/脉冲频率为0.5s/1min^(-1)条件下,通量强化比达1.20.与稳定流相比,脉冲流能有效延迟饱和盐水(333K)膜蒸馏过程通量急剧下降的发生.

PVDF membrane module was used to investigate the effect of pulse length（PL）and pulse frequency（PF）on the performance of sweeping gas membrane distillation（SGMD）process with pulsatile high concentration NaCl solution as the feed.The results show that when the feed flow rate,feed inlet temperature,coolant temperature,gas sweeping rate are fixed at 30 L/h,323 K,283 K,0.74 m3/h respectively,flux enhancement ratio is up to 1.20 at optimum PL/PF set（0.5s/1min-1）.And comparing to the steady flow,pulsatile flow can delay the occurence of sharp membrane flux decline in the membrane distillation of saturated NaCl solution（333K）.