高含氮印染废水强化脱氮处理组合工艺

为考察UASB-A/LO/O（缺氧/低氧/好氧）组合工艺的实际应用效果，将该工艺应用到规模为6 000 t/d的实际工程中，考察其对高含氮印染废水处理效果，同时采用微生物高通量测序对A/LO/O工艺中的微生物菌群结构进行解析.结果表明:在前处理废水进水流量为100 m3/h，染色废水进水流量为150 m3/h，同时A/LO/O工艺污泥回流比为50%左右情况下，COD_Cr、NH₃-N和TN的去除率分别达到91.6%、95.5%和73.5%；染色和前处理废水在改良UASB内均实现了高效厌氧氨化，染色废水厌氧出水中ρ（NH₃-N）/ρ（TN）保持在80%以上，前处理废水厌氧出水保持在85%以上；调节UASB运行参数可对VFAs（挥发性脂肪酸）进行有效调控，从而为后段反硝化工艺提供高品质碳源，实现高效脱氮；A/LO/O系统对COD_Cr、NH₃-N、TN有较好的去除效果，其脱氮性能主要靠变性菌门（Proteobateria）发挥作用，该系统中低氧池的微生物种类最为丰富且发生短程硝化反硝化，对污染物去除贡献最大，当低氧池△ρ（COD_Cr）/△ρ（TN）在18.6左右时，TN去除率最高，达到82%.研究显示，该组合工艺对工程中高含氮印染废水的脱氮效果良好. 

Combined Process Treatment of Printing and Dyeing Wastewater

The effects of Anoxia/Hypoxia/Aerobic (UASB-A/LO/O) combined process on printing and dyeing wastewater containing high concentration of nitrogen with capacity of 6000 t/d were studied. Under the conditions of inflow rates 100 m3/h and 150 m3/h for pretreatment and dyeing wastewater in improved UASB anaerobic tank, respectively, and the sludge reflux ratio at 50%, the final pollutant removal performed well. The removal efficiencies of COD_Cr, NH₃-N and TN reached 91.6%, 95.5% and 73.5%, respectively. The wastewater was treated by high efficient anaerobic ammoniation in the improved UASB process section. Ammonia nitrogen occupied more than 80% and 85% of TN in the anaerobic effluent of the dyeing and pretreatment wastewater, repsectively. In order to enhance the denitrification, volatile fatty acids (VFAs) could be controlled by adjusting the operating parameters of UASB, which could provide high-quality carbon sources for the following anoxic denitrification. A/LO/O process performed well for COD_Cr, NH₃-N and TN removal in printing and dyeing wastewater, and Proteobacteria played an important role in the denitrification process. The most abundant microbial species and shortcut nitrification and denitrification were observed in the micro-oxygen pool, which played an important role in the pollutant removal performance to some extent. In addition, it was considered that the optimal nitrogen removal reached about 82% when the ratio of △ρ(COD_Cr)/△ρ(TN) was around 18.6. The results showed that the combined process had a good effect on printing and dyeing wastewater containing high concentration of nitrogen.