Experimental Research On Nitrogen And Phosphorous Removal In SB-MBBR

At present, China’s rivers and lakes are subject to different degrees ofcontamination.Too much nitrogen and phosphorus lead to aquatic plant reproducesmassively, more than half of water appears the eutrophication.At the same time, withthe continuous improvement of the effluent discharge standards, the nitrogen andphosphorus removal becomes the main task in sewage water treatment process. In thisarticle, using sequencing batch moving bed biofilm reactor on sewage processing,research on nitrogen and phosphorus removal.The same time, the emphasis on theinfluence factors of nitrogen and phosphorus removal in SBMBBR, including theanaerobic and anaerobic time distribution, the influent C/P ratio and dissolvedoxygen, etc. The test results show that:The biological biofilm formation through three stages in SBMBBR using asingle-stage aerobic process in the first stage.There were the filamentous fungi, clockbug, tired branch bug, etc on the biofilm through the microscopic examination.In thesecond stage, extended aeration time to20h, the test results show that excessiveaeration can affect biofilm formation and cause economic burden.At the end of thethird stage of training, the highest removal efficiency of COD, ammonia nitrogen,TN, and TP up to89.77%,82.89%,64.21%,33%.using a single-stage aerobicprocess, there is no alternating anaerobic and aerobic conditions causing the removaleffect is poor.After hanging the membrane success,the test used the anaerobic/aerobicrunning process on sewage processing in SBMBBR. Anaerobic time is3h and aerobictime is7h. After25days of cultivation and domestication, the removal efficiency ofsewage processing in SBMBBR is higher,COD, ammonia nitrogen, total phosphorusremoval rate of up to87%,70%,57%.By adjusting the running time of each phase,has determined the optimal operation parameters: the temperature is about25,agitator speed is70-80r/min, anaerobic time is2h, the aeration time is6h.The resultsof the stable operation show that: the sewage treatment removal efficiency wasimproved, COD, ammonia nitrogen, TN, TP removal rate up to91%,82%,79%,72%.By examining the COD, the3-nitrogen, TN and TP conversion process inSBMBBR, the removal efficiency of COD is65.6%in the anaerobic stage,and thephenomenon of releasing phosphorus,the removal rate of TN reached78%at the endof aeration.It shown that had better performance of simultaneous nitrification and denitrification in the aerobic process,so that the simultaneous nitrogen and phosphateremoval was efficient.Limited the influent C/P ratio to20to120, it did not have a large effect on theremoval rate of organic matter. Along with the increase of the ratio of C/P, phosphorusremoval efficiency also increased.When its ratio increased to120, phosphorusremoval rate gradually decreased.This is due to high C/P ratio promote the GAOs tobe dominant and PAOs is restrained, resulting in phosphorus removal ratedecreased.When the influent COD concentration is too high, heterotrophic bacteriacompetes with nitrifying bacteria so that nitrification blocked.As the DO concentration of the aerobic phase continued to improve, along withammonia nitrogen removal efficiency to enhance.But the high DO concentration hassome effect on denitrification reaction inthe inside of the biofilm, thus nitrogenremoval effect decreased. At the same time, excessive aeration burned the internalenergy of the PAOs, resulting in phosphorus removal ability droped.