回流比对单级UASB-A/O处理晚期垃圾渗滤液短程脱氮的影响

采用"单级UASB-A/O组合工艺"处理实际晚期高氨氮城市生活垃圾渗滤液,在获得稳定的有机物与氮同步去除的前提下,重点考察了不同回流比条件下(100%～600%),UASB与A/O中的污泥分布、DO浓度,UASB中同时反硝化与产甲烷的活性,A/O中亚硝酸积累率的变化,组合工艺系统氮与有机物的转化与去除.结果表明,当回流...

Effect of recycling ratio on shortcut nitrification-denitrification of mature landfill leachate in a single-stage UASB-A/O system

A combined system consisting of an up flow anaerobic sludge blanket(UASB)and anoxic/oxic bioreactor was adopted for treating mature municipal landfill leachate rich in ammonia nitrogen(NH+4N).On the premise of the COD and nitrogen being removed simultaneously，the sludge distribution and DO concentration in UASB and A/O, denitrification and methanogenic activity in UASB, nitrite accumulation ratio variation in A/O, organic matter and nitrogen transition behavior in the combined system were analyzed at different recycling ratios（100%—600%).The results with the recycling ratio maintained at an appropriate level indicated that the sludge distribution characteristics and DO concentration in respective reactors were in a relatively better state.Gas production analysis showed that denitrifying bacteria and methanogen activity in UASB were maintained at homeostasis balance.Under the premise of ensuring the efficiency of nitrification, the selective inhibition of FA on ammonia oxidizing bacteria and nitrite oxidizing bacteria realizing control on nitrification rate to achieve a high rate of nitrite accumulation in A/O. According to the characteristics of liquid water and considering energy consumption, an optimal recycling ratio of 300% was suggested to achieve optimum system performance with the removal efficiencies of NH+4N,TN,COD reaching 99.3%，85.9% and 90.6% respectively and NO-2N accumulation ratio reaching 94.4%.