两级PNDPR耦合Anammox脱氮除磷工艺研究

Study on two-stage PNDPR coupled with Anammox for nitrogen and phosphorus removal

鉴于厌氧氨氧化工艺进水必须包含NO_(2)^(-)-N和NH_(4)^(+)-N两种基质,且只能脱氮,为在此基础上进一步实现除磷,提出辅以短程硝化技术,将除磷、脱氮技术相耦合,即短程硝化反硝化除磷串联厌氧氨氧化工艺.生活污水首先进入短程硝化反硝化除磷单元,主要实现NH_(4)^(+)-N转化为NO_(2)^(-)-N并去除COD,其部分出水与生活污水原水相混合再进入厌氧氨氧化单元,同时短程硝化反硝化除磷单元于缺氧条件下反硝化吸磷,待反应结束后两个处理单元的出水混合排放.实验结果表明,控制进水混合比为4.2可保证Anammox单元中C/N和NO_(2)^(-)-N/NH_(4)^(+)-N值分别为2和1.5,平均△NO_(2)^(-)-N/△NH_(4)^(+)-N=1.41,△NO_(3)^(-)-N/△NH_(4)^(+)-N=0.12,Anammox脱氮平均占比为85.2%,反硝化与Anammox反应耦合良好.整个系统稳定运行后出水COD、P、NH_(4)^(+)-N、NO_(2)^(-)-N和NO_(3)^(-)-N浓度分别为15.2,0.85,0.59,5.56,3.33mg/L,TN去除率为89.4%,通过PNDPR-Anammox耦合新工艺成功实现模拟生活污水的高效处理.

Considering that the influent of Anammox process must contain two substrates,NO_(2)^(-)-N and NH_(4)^(+)-N,and it could only be denitrified.In order to further realize phosphorus removal on this basis,this study proposed to combine phosphorus removal and nitrogen removal with partial nitrification technology,namely partial nitrification and denitrifying phosphorus removal tandem Anammox process:the partial nitrification and denitrification phosphorus removal unit was the first to pass into domestic sewage to convert NH_(4)^(+)-N to NO_(2)^(-)-N and remove part of COD.Part of the effluent was mixed with domestic sewage and enters the anaerobic ammonium oxidation unit.At the same time,the partial nitrification and denitrification phosphorus removal unit was denitrified and absorbed phosphorus under the hypoxia state,and the effluent of the two treatment units was mixed and discharged after the end of the reaction.The experimental results showed that controlling the influent mixing ratio to be 4.2 could ensure that the values of C/N and NO_(2)-N/NH_(4)^(+)-N in the Anammox unit were 2 and 1.5,respectively,the average△NO_(2)^(-)-N/△NH_(4)^(+)-N=1.41,△NO_(3)^(-)-N/△NH_(4)^(+)-N=0.12,Anammox nitrogen 85.2%on average,denitrification and Anammox coupling reaction was good.After stable operation of the whole system,the effluent COD,P,NH_(4)^(+)-N,NO_(2)^(-)-N and NO_(3)^(-)-N concentrations were 15.2,0.85,0.59,5.56 and3.33mg/L,respectively,and the TN removal rate was 89.4%.The PNDPR-Anammox coupling new process successfully realized the efficient treatment of simulated domestic sewage.