| Anaerobic digestion receives increasingly extensive application in sewage disposal field for the merit of little energy consumption,low cost,few excess activaled sludge,the ability of dealing with hard digestion organic compound moreover produces energy sources. Anaerobic baffled reactor gained altitudinal recognition and research in recent years as a new type anaerobic reactor,although there are several ABR instance in practical project,but there are more shortage about systemic theory study. This paper tries to study systemly the running performance of ABR at ambient temperature on the base of summing-up former productions in order to offer guidance and help for practical application.Two ABR model are devised with seven chambers and eight chambers,on condition of ambient temperature and unchangeable inflow COD and changes running condition by adjusting flux. Systemly measures COD and VFA and pH and alkalinity of outflow and methane yield and temperature,calculates COD removal rate and cubage loading and hydraulic loading,studies the running rule of ABR and its chambers,for the first time discusses and analyse the phenomenon of acidification phase separating with methane phase and the mode of increase loading. Reactor acidification and comeback are studied. Hydraulic characteristics is analysed by tracing experiment. The relationship of sludge quantity in ABR with running and sludge granulation is discussed by observation channel phenomenon and sludge granulation. Analysis of running parameter indicates that sludge loading can image generally the factor influencing reactor running,and for the first time edgeout substance concentration by sludge loading in monod model,and found a biology digestion kenetic model,at last calculate kenetic parameters using experimental date and make comparation between measure date and fore cast date.The study results of this paper indicate:(1)When ambient temperature above 18,and inflow COD keeping 4500mg/L,HRT between 84-24 hours,two reactor retain >90% removal rate under steady running,and the biggest removal rate is 98%,the removal rate in the reactor with 8 chambers is finer than the other.When the ambient temperature depress to 5-6,the running is seversly labefaction.) Outflow COD and cubage loading of every chamber depressed gradually along flow and keep steadiness after increasing loading;(3) Chamber outflow COD and VFA and alkalinity indicate the there is as separating phenomenon between acidification phase and methane phase,in ABR with 8 chambers acidification take place in the first two chambers and producing methane in the last four chambers;(4) The range of mode of increasing loading is suitable between 50-60%,and it is fast and effective;(5) the results of this paper and others indicate that the cubage using rate of ABR is high and deadspace between 7-20%. ABR prolongs the flow,enhance mixing and meeting between sludge and substance,strengthen effectively the matter transfer without increase volume of ABR. The flow in ABR is similar to the ideal flow which complete fixing partial and plug flow whole;(6) It is necessary that keeping plentiful sludge in ABR with good running,but channel flow will form when sludge is too much,which will effect the forming of granuler sludge and efficency of reactor,so it is suitable that the height of sludge bed lower than two thirds of effective depth. Seven are setup between chamber in order to preserve sludge in reactor and chambers,and large number of coast can be pincl if this means is adopted in projects;(7) The comparation results between measure data and forecast data prove that the kenetic model is good when forecast COD of outflow from chambers.
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