包埋厌氧氨氧化颗粒污泥的生活污水CANON工艺脱氮特性

Nitrogen removal characteristics of immobilization of Anammox granular sludge in domestic sewage CANON process

为实现厌氧氨氧化(Anammox)包埋填料在城市污水中的稳定脱氮,以除碳后的生活污水作为进水,通过间歇曝气的运行方式,研究了高氨氮废水处理系统中的厌氧氨氧化颗粒污泥(AnGS)及利用其制成的Anammox包埋填料在生活污水CANON工艺中的脱氮性能及微生物群落结构。结果表明,在生活污水CANON工艺启动过程中,AnGS系统的氨氮去除率和总氮去除率最高分别仅为65.9%和59.3%,而包埋填料后在启动仅10 d后,氨氮去除率和总氮去除率分别可达98.9%和72.4%以上,同时出水NH_(4)^(+)-N和TN均能满足《城镇污水处理厂污染物排放标准(GB 18918-2002)》中一级A的排放要求。提高曝气阶段的DO质量浓度(2.9~3.1 mg·L^(−1)提升到3.9~4.1 mg·L^(−1))会导致包埋填料出水NO_(3)^(−)-N质量浓度增长至9.7~11.1 mg·L^(−1),从而破坏CANON工艺中的短程硝化导致出水总氮不达标。但将DO浓度恢复后,包埋填料CANON工艺的脱氮效果能够恢复。运行后的包埋填料中AAOB主要菌属Candidatus Kuenenia和Candidatus Brocadia的占比为21.11%和1.04%,同时NOB主要菌属为Nitrospira,占比仅为0.53%,包埋填料在生活污水中能够保持AAOB菌群优势并有效抑制NOB的增长,因此将包埋固定化技术用于城市污水CANON工艺脱氮中具有广阔的前景。

In order to achieve the stable nitrogen removal of Anammox immobilized filler in domestic sewage,the decarbonized domestic sewage was used as the feed water,the aeration method was intermittent aeration,the nitrogen removal performance and microbial community structure of anaerobic ammonia oxidation granular sludge(AnGS)in the high ammonia wastewater treatment system and the Anammox immobilized filler made of AnGS in the CANON process of municipal wastewater were studied.The results showed that during the start-up of the CANON process of domestic sewage,the highest removal rates of ammonia and total nitrogen in the AnGS system were only 65.9%and 59.3%,respectively.After 10 days of start-up of the immobilized filler,the removal rates of ammonia and total nitrogen could reach over 98.9%and 72.4%,respectively,and the effluent NH_(4)^(+)-N and TN could meet the discharge requirements of level A in the“Emission Standard for Pollutants for Urban Wastewater Treatment Plants(GB 18918-2002)”.Increasing the DO concentration in the aeration stage(from 2.9~3.1 mg·L^(−1) to 3.9~4.1 mg·L^(−1))resulted in the increase of the effluent NO_(3)^(−)-N of the immobilized filler to 9.7~11.1 mg·L^(−1),thus the short-cut nitrification of the CANON process was destroyed and the effluent total nitrogen did not meet the standard accordingly.However,after the DO concentration was returned to previous value,the nitrogen removal effect of the immobilized filler CANON process could recover.After the immobilized filler operation,the main AAOB bacteria were Candidatus Kuenenia and Candidatus Brocadia,accounted for 21.11%and 1.04%,respectively,while the main NOB bacterium was Nitrospira,accounting for only 0.53%.Immobilized filler can maintain the advantages of the AAOB flora in domestic sewage and inhibit the growth of NOB,so the immobilization technology has broad prospects for the nitrogen removal from municipal wastewater by CANON process.