Sioutopoulos Dimitrios, Karabelas Anastasios, Mappas Vasileios
Chemical Process and Energy Resources Institute, Centre for Research and Technology-Hellas, 6th km Charilaou-Thermi Road, 57001 Thermi-Thessaloniki, Greece.
Department of Chemical Engineering, Aristotle University of Thessaloniki, 54623 Thessaloniki, Greece.
Membranes (Basel). 2019 Feb 1;9(2):21. doi: 10.3390/membranes9020021.
Significant gaps exist in our knowledge of ultrafiltration (UF) membrane fouling, due to mixtures of poly-saccharides and proteins, despite a fair amount of related research. To get new insights into fouling layer characteristics, experiments were performed under constant-flux, within the range of practical interest (15⁻90 L/m²h), with typical polysaccharides (sodium alginate, SA), proteins (bovine serum albumin, BSA) as well as their mixtures in various proportions (1:3, 1:1, 3:1), and total organic matter concentration of 30 mg/L. The feed-water salinity and calcium ion concentration were 2000 mg/L NaCl and 2 mM, respectively. The temporal evolution of such fouling layers on flat-sheet membranes was monitored by recording the trans-membrane pressure variation. The results show that the specific fouling resistance α is strongly affected by flux, and the fouling propensity of polysaccharide-protein mixtures is significantly enhanced compared to single foulants, i.e., when BSA and SA are alone. The fouling layers are compressible and their resistance α tends to increase with the mass ratio of alginate in the mixture, particularly at high fluxes. To quantify these effects, correlations are presented of the initial fouling resistance α with permeate flux J and of the evolution of α. R&D priorities are suggested on this topic of mixed foulants.
尽管已有大量相关研究，但由于多糖和蛋白质的混合物，我们对超滤（UF）膜污染的认识仍存在重大差距。为了深入了解污染层特性，在实际感兴趣的通量范围（15⁻90 L/m²h）内进行了恒通量实验，使用典型的多糖（海藻酸钠，SA）、蛋白质（牛血清白蛋白，BSA）以及它们不同比例（1:3、1:1、3:1）的混合物，总有机物质浓度为30 mg/L。进水盐度和钙离子浓度分别为2000 mg/L NaCl和2 mM。通过记录跨膜压力变化来监测平板膜上此类污染层的时间演变。结果表明，比污染阻力α受通量的强烈影响，与单一污染物（即单独的BSA和SA）相比，多糖 - 蛋白质混合物的污染倾向显著增强。污染层是可压缩的，其阻力α往往随着混合物中海藻酸盐的质量比增加而增加，特别是在高通量时。为了量化这些影响，给出了初始污染阻力α与渗透通量J以及α演变的相关性。针对混合污染物这一主题提出了研发重点。
