Experimental Study Of A_mO_n Integrated System In Treating Small Town Sewage

As domestic wastewater is the main component of small town sewage,treating proportion is low and a large amount of wastewater is seldom treated.In view of this problem,artificial water was applied to simulate small town sewage as research object in this experiment,and A_m O_n integrated system was applied to treat the wastewater.By the scale experiment,the operation conditions and system parameters of A_mO_n integrated system were studied.This paper is divided into the following four parts and conclusions.?1?In the initial stage of the system,low-load water was taken in order to adapt the sludge to the influent load,the HRT was set to 18h,and the remaining sludge was not discharged.Then the influent flow was gradually increased every day,and a week after a design load was taken.During the start-up stage,the COD,NH₄⁺-N,TN and TP of the system were detected every day.On the 21st day,the concentration of main pollutants in the system was stable,and in the following nine days,the concentration of effluent pollutants remained stable,indicating that the sludge was domesticated.?2?HRT optimization experiment of A_mO_n integrated system.The results show that a proper extension of the HRT of the system will improve the removal efficiency of the system.However,when HRT was extended from 10h to 12h,there was no significant change in the removal effect of the system,indicated that when HRT was 10h,the original water and activated sludge in the system has been fully reacted.After comprehensive consideration,it is considered that 10h is the best HRT for the system.?3?The best C/N ratio experiment of A_mO_n integrated system.The results show that when the C/N was increased to 10:1 from 6:1,the system will gradually improve the removal effect of pollutants.But after the C/N was increased to 10:1,the system's removal rate of pollutants grew slowly.The integrated structure of the device leads to the poor anaerobic environment in the system,and the effect of phosphorus removal is not ideal,that make phosphorus removal mainly through microbial assimilation and lower phosphorus removal.Considering the water quality of small town sewage and the additional cost of carbon sources,C/N is selected as 8:1 as the optimum condition,while the system has better organic removal and denitrification effect.?4?The research on the optimum aeration-stopping period experiment of A_mO_n integrated system.The results show that the A_mO_n integrated system had good organic removal and nitrification effect when the aeration-stopping period was 40min?aeration30min,stopping 10min?.When the aeration time was equal to 30min and the stopping time was extended from 10min to 30min,the removal effect of the system was gradually reduced.When the stopping time was equal to 10min and the aeration time was extended from 15min to 30min,the system's removal rate of pollutants can be effectively improved.Therefore,the optimum operating condition of the system is that the aeration-stopping period is 40min?aeration 30min,stopping 10min?.