【摘要】 采用三室双极膜电渗析脱除苏氨酸母液中硫酸盐,探讨连续操作对电渗析器性能变化的影响,并测定连续实验前后离子交换膜的面电阻,考察膜污染情况.结果表明,苏氨酸母液中盐转化率达97%,酸室中得到0.50mol/L的H+,碱室中得到0.53mol/L的OH-,以阳离子计算的电流效率为60.33%,能耗为229.37kW·h/kmol;随批次增加、操作时间延长,单位膜通量能耗和膜堆平均电阻增大,电流效率和膜通量减小,电渗析器性能下降;连续操作后,阴膜面电阻较使用前增加1.77Ω·cm2,升高44.8%,双极膜面电阻增加0.91Ω·cm2,升高19.5%,离子交换膜被污染.更多还原

【Abstract】 The desalination of sulfate in threonine isoelectric supernatant by three-compartment electrodialysis with bipolar membrane was studied.The device performance during five successive batches of electrodialysis was investigated.In addition,the area resistance of ion-exchange membranes before and after batch operation was measured to detect the membrane fouling.The results showed that the transform rate of sulfate in threonine isoelectric supernatant reached 97%,and H+ concentration of 0.49 mol/L and OH- concentration of 0.44 mol/L were obtained by the electrodialysis in acid and base cells,respectively.Whereas,the average current efficiency and energy consumption of the three-compartment electrodialysis with bipolar membrane calculated on the basis of cations were 60.33% and 229.37 kW·h/kmol,respectively.With increasing of batch runs and prolonging of operation time,the energy consumption of unit flux and average stack resistance increased,and average current efficiency and flux decreased,the device performance was deteriorated.Moreover,the area resistance of anion and bipolar membranes was increased by 44.8%(1.77 Ω·cm2) and 19.5%(0.91 Ω·cm2),respectively,which was caused by membrane fouling.更多还原