将双层刮膜法制备的具有高开孔率表面的微孔膜应用于过滤高浓度悬浮液体.研究了悬浮液颗粒浓度、粒径大小、膜的初始纯水通量、膜的正反面以及过滤方式几个方面对膜过滤性能的影响.结果表明,膜的初始纯水通量对颗粒的截留率和过滤通量的稳定性几乎没有影响;在一定的误差范围内,悬浮物的浓度对膜的稳定通透性能起着决定性的作用;颗粒粒径越大初始通量就越大.PSf膜的正面过滤初期通量没有底面过滤的大,但稳定通量始终高于底面过滤的稳定通量.PSf膜对啤酒的过滤效果优于PES膜,能过滤啤酒的最大质量Gmax是PES膜的4倍多,所以,具有高开孔率表面的PSf膜可以接纳更多的污染物质,具有较好的过滤性能.对于高浓度悬浮液的澄清来说,错流过滤的效率要高于死端过滤.
This report described the application of microfiltration PSf membrane in clarification of highly suspended solution.The PSf membrane was prepared via a co-casting technique.The effects of CaCO3 particle concentration,particle diameter,membrane initial permeability,reversal of filtration surface of the membrane on the filtration performance were investigated.Results showed that the initial water permeability has no significant effect on the filtration stability.The particle concentrations controlled the steady membrane permeability.In case the particle diameter is lower than the membrane pore size,the pore blockage leads to drastic decline in permeability;however,when particle diameter is larger than the membrane pore size,cake formation is the main reason for the permeability degradation.Reversing the filtration surface,the filtration using top surface showed slightly higher permeability than bottom surface.In beer filtration,open surface PSf membrane evidently showed advantage against 0.4 μm PES membranes.Results indicate that the open surface PSf membranes are suitable for clarification of highly suspended solution,for example suspension with particles or bacteria,beer,wine or active sludge.