基于海水和盐田水的正渗透驱动液

采用海水和盐田水作为驱动液,研究正渗透过程中的通量变化和膜污染特征,探索其作为驱动液的可行性。结果表明,海水和盐田水含有大量的盐离子,具有高的渗透压,海水、2#、5#和9#盐田水与0.42、0.8、2.2和4.2 mol/L的氯化钠具有同样的通量行为。随海水和盐田水浓度增加,通量增加,同时污染也越严重。扫描电子显微镜观察和荧光光谱分析发现,盐田水中的硅酸盐和有机物会沉积在膜表面,引起比较严重的膜污染,尤其是高浓度的盐田水。海水和盐田水作为正渗透过程中的驱动液需要进行一定的预处理。

Draw solution in forward osmosis based on seawater and saltern brine water

Seawater and saltern brine water were used as draw solutions in forward osmosis, and the flux behavior and membrane fouling of FO water were studied. Seawater and brine water contain large amount of salts which would generate high osmotic pressure. Using seawater, 2#, 5# and 9# brine water as draw solutions could achieve identical flux behaviors with 0.42, 0.8, 2.2, 4.2 mol/L NaCl solution. With the increase of brine water concentration, flux became larger, and also the extent of membrane fouling. From the SEM-EDX observation and EEM dialysis, the silicate and organic matters in the brine water may deposit on the membrane surface and cause severe membrane fouling, especial for brine water with high concentration. Seawater and brine water are potential to be used as draw solution in FO which need pretreatment.