The Treatment Of High Strength Wastewater With High Ammonia Using ABR Followed By Modified SBR

As one typical high strength wastewater with high ammonia, the wastewater fromthe scaled farm is in rich of ammonia and phosphorus, which will result in a series ofadverse effects known as cultural eutrophication. Manure leachate into the soil willcause groundwater pollution. At the same time, the ammonia, sulfide and methanegive off the odor of intolerance. The environmental pollution caused by developingscaled farm is on the way of getting worse, especially for the countryside. So, greatconcern should be given to the pollution of the manure. In this paper, we will studythe treatment of the high strength wastewater with high ammonia through treatingsimulated piggery wastewater using ABR followed by modified SBR. In fact, the wastewater and manure of most large-scale farms in China is noteffectively treated. There are two reasons for that :one is that the feeding farm has thelower economic benefits, another is that the employed measures neglect the removalof nitrogen and phosphorus. Subsequently, it is of great necessity to develop a technology with characteristicsof low price and high rate. Anaerobic unit followed by aerobic unit is proved to be a promising process. Ourresearch is concerned about the selection of reactors and the study of performance. ABR has several advantages over well-established systems such as the up-flowanaerobic sludge blanket and the anaerobic filter. These include: better resilience tohydraulic and organic shock loadings, longer biomass retention times, lower sludgeyields, and the ability to partially separate between the various phases of anaerobiccatabolism. SBR has been developed in recent years to achieve high quality effluentin regards to carbon, nitrogen and phosphorus compounds. The technology used inour research is as simple as possible yet still achieve a high degree of BNR, named asmodified SBR. It has the characteristics of ICEAS,CASS and IDEA, because ,tosome degree, it is alike they three, as well as it is different from them. In short, weprove a process, which has two units: ABR and modified SBR, is of low price andhigh rate and can meet the need of swine manure treatment. The starts-up of the ABR lasted for 101 days with thermophilic bacteria. Underthe designed volumn loading rate of 20kg(COD)/(m3d), the removal rate of CODachieved 72%. When the temperature was lowered to 25℃, COD removal rate was70% ,which was of little difference from the former. Beside, the conclusion could bedrew that the starts-up is relative to the amount of the sludge seeded as well as theoperation manners. HRT, COD concentration in the influent, reactor sequence (especially the settle),nitrified liquid recycle were designed to be four variables, whereby, eighteenconditions were studied. The study showed that HRT and aeration had both influenceon the removal rate of COD and NH3-N, while the COD concentration in the influentand recycle had little on COD removal but great on NH3-N. The optimum conditionwas: HRT=8hr, CODin=800mg/L, reactor sequence: aeration 2hr and 55 minutes/settle1hr/decant 5 minutes, recycle 200 percent of the nitrified liquid. Under that condition,the COD and NH3-N removal rate were 90% and 74.4% respectively.