亚硝化-厌氧氨氧化联合工艺处理高含氮废水的研究

采用实验室规模的亚硝化-厌氧氨氧化联合工艺,研究其对高含氮、低C/N废水的处理能力.结果表明,亚硝化反应器的水力停留时间控制在1.0d时,亚硝化活性比较稳定,进水氨氮浓度对其影响不大.进水氨氮浓度在400～600 mg/L时,出水亚硝酸氮浓度都在260～280 mg/L,可以通过控制进水氨氮浓度调节出水亚硝酸氮/氨氮的比率.亚硝化反应器出水的亚硝酸氮/氨氮的比率对厌氧氨氧化脱氮率有重要的作用.当进水氨氮浓度为480 mg/L时,出水中亚硝酸氮/氨氮的比率为1.2左右,进入厌氧氨氧化反应器的氮物质去除率达到     

A comparative study of eutrophication evaluationmodels based on SOM neural network and SVM

A SBR inoculated with conventional activated sludge was employed to cultivate aerobic granular sludge.Under the selective pressure of settling time, the formation of nitrifying granules enriched with the ammonia oxidizing bacteria (AOB) was achieved by increasing the nitrogen loading rate (NLR).The nitrifying granule was shaped like a sphere or a ellipsoid with an equivalent diameter of approximate 1.1 mm, an average settling velocity of 1.9 cm·s-1and the sludge volume index of 18.2～31.4 mL·g-1.As the aerobic granular system was operated stably, the NLR reached a value of 0.045 5 kgNH4+ N· (kg MLSS·d)-1 with ammonia removal efficiency above 95% and nitrite accumulation ratio in the range of 80%～90%.The NLR was 4.55 times higher than that of the start up period.The enrichment of the nitrifying bacteria was quantified by FISH analysis which indicated that AOB was 14.9% of the total bacteria and nitrite oxidizing bacteria (NOB) was 0.89%.It is concluded that the associated inhibition of FA at the start of the reaction and FNA at the end of the reaction would be the key factors to start up and maintain the stable nitritation.