Aerobic Denitrifying Granular Sludge Of Dynamic Storage

Aerobic granular sludge technology is a new type of sewage treatment in recent years, Because of the aerobic granular sludge sedimentation speed, high biomass and diversity of microbial populations, so by the researchers attention. However, aerobic granular sludge such as long start-up time, storage stability decline after problems, in the actual process of wastewater treatment greatly limits its application. So after aerobic denitrifying granular sludge idle, to explore the activity of nitrifying bacteria in aerobic denitrifying granular sludge recovering quickly become denitrifying granular sludge in sewage treatment with key focus in the field of practical application. Therefore, the main content of this topic for aerobic denitrifying granular sludge critical activity and research of dynamic storage.Aerobic nitrifying granule sludge cultivated in sequential batch reactor (SBR) was used to investigate the critical activity point of granules and the effect of different ammonia concentration and aeration time on reactivation after storage Results showed that, storage of nitrifying bacteria in different time activity (SOUR, O2/VSS) difference is bigger, the specific oxygen utilization rate (SOUR) of granules before storage was13.15mg·(g·h)-1, after storage periods of20days, the SOUR decreased by1.26mg·(g·h)-1, after5cycles reactivation, the SOUR can recover. But storage periods of30days, the SOUR decreased by11.63mg·(g·h)-1, after51cycles reactivation, the SOUR can recover. A longer recovery time for this storage method, after the comprehensive comparison and analysis, we put forward the critical activity of denitrifying granular sludge is start activity recovery when the nitrifying bacteria SOUR began to decline, To achieve the goal of fast recovery.On the basis of the critical activity, we begin to restore the activity when the denitrifying bacteria reduced to critical activity, and then stored into the next cycle, the store method named the dynamic storage. Different influent ammonia concentrations of20,30and40mg·L-1were applied to reactivate the aerobic granules. Highest SOUR could be achieved when feed with ammonia concentrations of40mg·L-1after reactivation. After three times of dynamic Storage, the SOUR remained stable. Different aeration time of1,2and3h were applied to reactivate the aerobic granules. Highest SOUR could be obtained when aeration time of1h was applied after reactivation and remained stable along with dynamic storage. In order to reflect the advantage of dynamic storage, simultaneously at the same time at the long-term storage of the comparison experiment of aerobic denitrifying granular sludge, results show that after long-term storage, the aerobic denitrifying granular sludge after a month of activation, Nitrifying bacteria SOUR before return to store only94.98%. Aerobic denitrifying granular sludge, therefore, the dynamic storage way is superior to storage for a long time, in comparison, the dynamic storage not only short recovery period, save power consumption, and can hold the denitrifying bacteria SOUR at relatively high level, avoid the long-term storage recovery cycle long defects, For aerobic granular sludge technology applied in the practical engineering provides the theoretical basis and technical support.