Research On Inductive Cultivation Of Aerobic Granular Sludge And The Operation Characteristics Of Reactors

Aerobic granular sludge technology is a new type of highly efficient biological wastewater treatment technology based on the anaerobic granular sludge. Aerobic granular sludge have attracted much attention due to its good removal capability of nitrogen and phosphorus and organic matter. In this study, aerobic granular sludge was cultivated from vaccination flocculent activated sludge in SBR reactor by adding inducers. And the removal ability to high ammona nitrogen and the tolerace ability to toxic organic compounds of the granular sludge were evaluated. The main contents of this paper were as follows:1. The zeolite powder was used to acclimate aerobic granular sludge in SBRs. The effect of zeolite on the forming time, morphological structure and decontamination ability were studied. After 90 days domestication, aerobic granular sludge was formed through adjusting the ratio of COD/N continuously. The average particle size of granular sludge was 2.5 mm, MLSS was 7.36 g·L-1, SVI was 34.9 mL·g-1. The removal rate of COD, NH4+-N, TN was 92.9%,98.5% and 95.7%, respectively.2. The PAM was used to acclimate aerobic granular sludge in SBRs. The effect of PAM on the forming time, morphological structure and decontamination ability were studied. After 90 days domestication, aerobic granular sludge was formed through adjusting the ratio of COD/N continuously. The average particle size of granular sludge was 2.2 mm, MLSS was 6.45 g·L-1, SVI was 30.87 mL·g-1. The removal rate of COD, NH4+-N, TN was 92%,98.7% and 95.4%, respectively.3. The synchronous nitrification and denitrification action of aerobic granular sludge was researched during a long-term domestication process. After 150 days of cultivation, MLSS and MLVSS of aerobic granular sludge was stability in 14.52 and 10.76 g·L-1, respectively, and the ratio of MLVSS/MLSSwas 0.74. The SVI5 and SVI30 of granular sludge decreased to 31.12 and 30.32 mL·g-1, respectively, and the ratio of SVI5/SVI30 was 1.02. The settling ability of the aerobic granular sludge was good, and the particle size was between 2 and 3 mm. The performance of simultaneous nitrification and denitrification was quite well. The degradation curve of one cycle showed that the removal rate of COD, NH4+-N, TN and TP were 90%,98%,88%, and 70%, respectively. The ammonia nitrogen degradation kinetics of aerobic granular sludge was explained by monod equation:Vmax=33.22 mg·(g-1-VSS)·h-1, k=107.15 mg·L-1.4. The effect of methyl orange with various concentration on the water treatment performance and the EPS of the aerobic granular sludge was examined in SBRs. The changes in the concentration of NH4+-N、NO2--N、NO3--N、COD and the properties of EPS during one cycle showed that methyl orange could effectively inhibit the activity of nitrifying bacteria, whereas, influence the ammonia oxidizing bacteria a little. The methyl orange decreased the MLSS of sluge, at the same time, promoted the secretion of protein for microbial selfrepair.