Aerobic Granular Sludge Short-range Nitrification And Denitrification

At present, traditional technology of biological nitrogen removal is with somedisadvantages in treating high concentrated ammonia-nitrogen wastewater, so the newtechnology of biological nitrogen remova becomes the core of studying. Aerobicgranulation is immobilized biological technology based on anaerobic granulation. Ifnitrosification-denitrification can be realized by controlling some conditions in this process,time of reaction can be shortened and energy also can be saved.Based on the latest researches of nitrosification-denitrification and aerobic granularboth in and abroad, in this paper, active sludge and anaerobic granular were used asfeeding sludge to culture and domesticate active sludge of nitrosification-denitrificationand aerobic granular, physicochemical properties during granulation and nitrogen removalperformance of the sludge were studied. And then aerobic granular sludge was used totreat high concentrated ammonia-nitrogen wastewater. Factors affecting the performanceof nitrogen removal by aerobic were studied.The result showed that the ammuculation of NO₂^--N becomes steady after two monthsso the nitrosification-denitrification is realized, anaerobic granular was transferred intoaerobic granular as feeding sludge. During granulation, the physicochemicalproperties(production rate of MLVSS,EPS) of feeding sludge altered regularly.We got the optimal parameter of the controlling nitrosification-denitrification bytreating high concentrated ammonia-nitrogen wastewater, pH=8.0, T=30℃,DO=0.5～1.0mg/L, the accumulation ratio of NO₂^--N is over 90％, active sludge andanaerobic granular were used as feeding sludge to culture and domesticate aerobicgranular, aerobic granular cultured was used to treat high concentrated ammonia-nitrogenwastewater, the removal rate of ammonia-nitrogen can stay at 90％, the optimal runparameter of reactor contolling aerobic granular is pH=8.0, T=30℃DO=0.5～1.0mg/L,HRT=10h.