| Aerobic granulation is a promising technology that has great potential in the wastewater treatment due to the advantages of excellent biomass settleability, highly organic loading rate, simultaneous nitrification and denitrification and biological phosphorus removal. However, the effluents of the granular sludge reactors are often not stable, resulting from the washout of mixed liquor suspended solids (MLSS). Therefore, firstly, in the SBR, the cultivating method at low temperature, main microorganism and stability of aerobic granules were studied. Then, based on the research results, aerobic granulation technology was combined with the membrane bioreactor for developing a sustainable technology of low energy consumption, low investment cost, low running cost and high efficiency. This paper includes following research works:(1) Characteristics of aerobic granular sludge in the GSBRAt low temperature, aerobic granules could be cultivated quickly in SBR. And the cultivated aerobic granules dominated by filamentous have good settleability, high content of extracellular polymeric substances (EPS), and good removal efficiency of organic matters. At normal temperature, the influences of operation disruption and ammonia and COD concentrations in influent on aerobic granules were studied, the main microorganism in granules was isolated and cultured, and mechanism of phosphorus removal in the sole aerobic condition was analyzed. It indicated that aerobic granules could be slightly influenced by operation disruption, but could be seriously influenced by ammonia and COD concentrations in influent. Yeast and mould were found to be the main microorganism. Finally, a two-stage mechanism of phosphorus removal was simulated in the granular SBR and then testified systematically.(2) Characteristics of SBGDMBRUnder alkalescent and high ammonia concentration environment, aerobic granules with highly nitrification and denitrification potential and accommodating to high ammonia concentration were successfully cultivated. Then, the SBGDMBR was developed by seeding this kind of aerobic granules in the SBDMBR. Results showed that SBGDMBR had great ability in disposing cesspool wastewater. And when the membrane flux was 5-30 times of that in the common DMBR, dynamic membrane could operate normally more than 20 days without membrane cleaning, and membrane flux could be 100% recovered by the washing of high pressure water. Moreover, the influences of sludge discharging frequency and effluent discharging mode on SBGDMBRR were studied.(3) Characteristics of CFGDMBRAerobic granular sludge accommodating to continuous-flow mode was successfully cultivated under the selective pressure of granule size in SBR. And a novel continuous-flow granular dynamical membrane bioreactor (CFGDMBR) was developed by seeding this kind of aerobic granules into the continuous-flow dynamical membrane bioreactor. The aerobic granules existing stably in the CFGDMBR had the characteristics of small particle size, bad settleability, loose structure and high water content.During the operation period of more than 70 days, CFGDMBR presented good organic and ammonia removal capabilities, 85% and 75%, respectively. Moreover, when DO was about 3.0-6.0 mg/L, CFGDMBR had TN and TP removal rates of 67% and 58%, respectively. Furthermore, the CFGDMBR system presented the characteristics of stability, strong anti-shocking of organic and hydraulic loading, low membrane resistance and long operation cycle. At last, the mechanisms of formation and fouling of dynamic membrane was built, and the methods for calculating the optimum cross-flow rate on the membrane surface and aeration gas amount for controlling membrane fouling were provided.
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