Study on anoxic-oxic process treating for dioscorea zingiberensis wastewater

The purpose of this paper was to investigate the characteristics of anoxic-oxic (A/O) process treating for dioscorea zingiberensis wastewater. Calcium oxide was added into the wastewater to adjust the pH value in the pretreatment, the 0.45g/L calcium oxide concentration was chosen as the optimum concentration. The average B/C (BOD/COD) value in the influent of A reactor was 0.35, and after the treatment, the average B/C value was 0.5. The results showed that the biodegradability of the wastewater was improved in A tank. The problems of foam, white sludge and sludge bulking also were discussed in the paper. The ammonia nitrogen and total nitrogen removal rate were 87.7% and 77.5% by the A/O process, the results showed that the A/O process had a good effect to nitrogen removal and the A reactor A/O played the major role in the nitrogen removal.