膜蒸馏处理谷氨酸发酵液工艺与影响因素分析

以质量分数11％的谷氨酸发酵液为对象,研究了膜蒸馏技术对谷氨酸的分离效果、脱色效果和产水质量,探讨了温度、谷氨酸浓度提高率对膜分离的影响.结果表明:利用膜蒸馏技术可以显著提高谷氨酸滤液和谷氨酸脱色液中的谷氨酸质量分数(由最初的11％分别浓缩到63.2％和65.17％).采用脱色工艺可以降低膜污染、提高膜蒸馏的通量.用正交试验进行脱色试验,方差分析结果表明各组之间活性炭用量具有显著性差异,其最佳方案为活性炭用量30 g/L、脱色时间0.5h、转速120 r/min.气相色谱法检测可知,产水中挥发性物质各组分的出峰时间和谷氨酸滤液气相色谱的出峰时间相同,表明膜蒸馏产水可以回到谷氨酸发酵罐中循环再利用,以降低生产成本、减少能耗和污染、提高产水利用率.

Effect of Membrane Separation Technology on VMD of Glutamic Acid

Taking the 11% glutamic acid fermented liquid as testing samples, the effects of vacuum membrane distillation technology on the VMD of glutamic acid, decolorization and reuse of waste water were explored. The effects of heating temperature and concentration multiple on VMD enrich were also examined. The research results indicated that in the VMD process, with the membrane distillation technology, the glutamic acid concentrate in the glutamic acid filtrate liquid and the decolorization liquid was increased from 11% to 63.2% and 11% to 65.17%, respectively. Decolorizing process by using active carbon was able to reduce membrane fouling and improve membrane flux. After L9(34) orthogonal decolorizing test, variance analysis result showed that active carbon was the priority factor to decolorization. The level of activated carbon was 30g/L. The decolorization time was 0.5h and the revolving speed was 120r/min. The results of water product on membrane distillation and GC testing indicated that the peak time of seven volatile substances in water product were similar to the glutamic acid filtrate and they were inferred the same materials. Therefore, the water product by filtrate membrane distillation can be reused to original fermentation liquid and improve water utilization efficiency.