Study On Optimizing The Cultivating Conditions Of Aerobic Granular Sludge With Orthogonal Test

Utilize self-made SBR reactor to culture aerobic granular sludge using regulating method of gradually improving influent loads on the condition of anaerobic-aerobic alternative operation. According to the characteristics of AGS, choose five factors:COD, C/N, anaerobic time, hydraulic retention time and aeration rate, which influence AGS granulation. Using orthogonal test, explore the influence degree of the five factors and seek the optimum cultural condition of AGS. And it studys the removal law of COD and ammonia nitrogen in one cycle and analyses and discusses the formation mechanism of AGS. According to the experiment, the significant degree of influencing granulation rate successively is: COD-settling time-C/N-aeration rate-hydraulic retention time. The optimum cultural condition is as follows. The influent COD is 600-1300 mg/L; The settling time is10min; The anaerobic time is 30 min; The influent C/N is 10:1; The aeration rate is 0.2 m3/h; The HRT is 270min. And the removal rates in COD and ammonia nitrogen of AGS cultured in the condition are 96% and 83%. AGS have high biological activity and most of the pollutant is removed in 1h after aeration.