Research of ganglioside extraction wastewater treatment process
神经节苷脂生产废水处理技术研究

Based on the characteristics of ganglioside extraction wastewater containing a lot of protein and high concentration COD,a sequential isoelectric point or coagulation precipitation,anaerobic-aerobic biological,chemical precipitation,and Fenton-like oxidation process has been developed to treat the wastewater in this study.The results showed that the isoelectric point of the wastewater was around pH=2.2 and the COD removal efficiency was over 30% after isoelectric point precipitation,but the protein settling velocity was very slow at isoelectric point.The optimal conditions as poly-ferric sulfate(PFS) used for the wastewater coagulation were pH=7~7.5 and PFS dose=500~750 mg/L,respectively.Under optimal coagulation conditions,the wastewater COD value was decreased from about 27 000 mg/L to about 13 000 mg/L through coagulation.The effluent of coagulation unit was treated by anaerobic(HRT=48 h) and aerobic(HRT=84 h) biological processes,and which COD value was decreased to about 600 mg/L after biological treatment.Since the PO3-4-P concentration in the biological system effluent was about 24 mg/L,2~3 mmol Fe3 /L was added to remove phosphate through precipitation and over dosed Fe3 could be worked as the catalyst of Fenton-like oxidation in the next step.The final effluent COD level could reach the Integrated Wastewater Discharge Standard of China as the H2O2(30%) dose was between 2 and 3 mL/L in the Fenton-like oxidation process.