摘要
为缓解电渗析膜污染,提高电渗析性能,采用阴膜扩散渗析对待脱盐的赖氨酸离子交换废液进行净化处理,对扩散渗析回收的(NH4)2SO4溶液进行电渗析脱盐浓缩。结果表明,当扩散渗析流量为5.6 L/h时,扩散渗析的扩散系数达2.24×10^-7 cm^2/s,离子交换废液中(NH4)2SO4透过率约为30%,可截留90.1%Mg^2+和94.5%有机氮、80.3%蛋白、86.0%总糖、79.3%化学需氧量(COD);与直接电渗析赖氨酸离子交换废液相比,对扩散渗析回收的(NH4)2SO4溶液进行电渗析脱盐浓缩,SO42-膜通量、电流效率分别提高了55.7%和18.3%,操作时间、单位膜通量能耗分别降低了26.1%和42.3%。用扩散渗析净化赖氨酸离子交换废液可有效缓解后续电渗析的膜污染,提高电渗析性能。
During the current fermentation process of producing lysine, large amount of organic waste water containing high-concentration salt were generated with the addition of inorganic acid-base regulators. When directly using conventional electrodialysis method to recover(NH4)2SO4 from lysine ion-exchange waste water, the ion-exchange membranes of electrodialysis were easily contaminated by pollutants in the waste liquid like high-valent ions, proteins, sugars and so on. In the diffusion dialysis method using membrane, there were many advantages such as low energy consumption, easy for operation, no pollution of the environment and so on. To reduce the membrane fouling during electrodialysis process and improve its performance, diffusion dialysis with anion-exchange membrane was adopted to clean lysine ion-exchange waste water, then carried out electrodialysis. The results showed that when the flow rate of diffusion dialysis was 5.6 L/h, among inorganic ions and organics investigated, 90.1% of Mg^2+, 94.5% of total organic nitrogen, 80.3% of the protein, 86.0% of the total sugar and 79.3% of chemical oxygen demand(COD) were rejected reasonably and nearly 30% of(NH4)2SO4 were recovered by diffusion dialysis with the dialysis coefficient of 2.24× 10^-7 cm^2/s. Moreover, compared with the process performance of(NH4)2SO4 recovery from lysine ion-exchange waste water by electrodialysis directly, the experiment that cleaned the feed solution by diffusion dialysis firstly and then carried out electrodialysis could increase the membrane flux of SO4^2- and the average current efficiency by 55.7% and 18.3% respectively, and decrease the operation time and the energy consumption of unite flux by 26.1% and 42.3% respectively. It was proved that cleaning lysine ion-exchange waste water by diffusion dialysis was a feasible method to mitigate ion-exchange membrane fouling and improve the process performance of electrodialysis.
作者
魏允
王倩
丛威
Yun WEI;Qian WANG;Wei CONG(State Key Lab of Biochemical Engineering,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China;College of Life Science,University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《过程工程学报》
CAS
CSCD
北大核心
2019年第5期975-981,共7页
The Chinese Journal of Process Engineering
基金
国家自然科学基金资助项目(编号:21506223)
关键词
电渗析
膜污染
扩散渗析
赖氨酸离子交换废液
净化
electrodialysis
membranes fouling
diffusion dialysis
lysine ion-exchange waste water
cleaning
