Application of aerobic granular sludge technology in the treatment of high ammonia printing wastewater

High ammonia printing wastewater was treated by aerobic granular sludge technology. The process of acclimation of aerobic granular sludge and the removal effect of pollutants and microbial community structure were investigated. The application practice shows that for the influent high ammonia nitrogen printing wastewater with NH 3 -N of 200 ~ 350mg/ L, TN of 250~400mg/L, and COD of 600~1000mg/ L, the aerobic sludge granulation can be completed after 60 days of acclimation and culture, and then 70 days of stable operation with a full load. The effluent COD of aerobic granular sludge reactor is less than 200mg/L, NH 3 -N is less than 15mg/ L, TN is less than 30mg/ L, and the average total removal rates are 99.3%, 93.4%, and 86.9%, respectively, which are far superior to the indirect discharge standards in Table 2 of Textile Dyeing and Finishing Industrial Water Pollutant Discharge Standard (GB 4287-2012). The results of high-throughput sequencing showed that compared with the inoculated sludge, the community diversity in aerobic granular sludge was lower but the community richness was higher, and the abundance of nitrifying and denitrifying functional bacteria increased significantly. Nitrosomonas, Nitrospira, and Solitalea are the main nitrification and denitrification bacteria in aerobic granular sludge, respectively.