HCO_3^-对部分亚硝化-厌氧氨氧化联合工艺脱氮效能的影响

Effect of HCO_3^- on Nitrogen Removal Efficiency in Partial Nitritation-ANAMMOX Process

利用已经启动并达到稳定运行的部分亚硝化-厌氧氨氧化联合工艺,研究了HCO-3对部分亚硝化-厌氧氨氧化联合工艺脱氮效能的影响.结果表明,当C/N比由2降低到0.17时,因HCO-3投加量的限制,亚硝化区和厌氧氨氧化区p H值大幅下降,从而导致各区域氮素转化效能受限.联合工艺的氮去除速率由1.3 kg·(m3·d)-1下降到0.40 kg·(m3·d)-1,下降幅度达到69.3%.在联合脱氮工艺运行过程中,降低HCO-3对亚硝化菌、厌氧氨氧化菌和硝化细菌活性的影响依次下降.当C/N比恢复到1时,联合工艺的脱氮效能很快恢复到1 kg·(m3·d)-1,说明短期内HCO-3限制对联合工艺氮素转化效能的影响能够快速恢复.通过拟合后发现,进水C/N比值与联合工艺脱氮效能存在明显的相关性.

The effect of HCO-3on nitrogen removal efficiency in partial nitritation-ANAMMOX process was studied by using the combined process of partial nitritation and ANAMMOX has been started and achieved the stable operation of nitrogen removal. The results showed that,when the ratio of C / N decreased from 2 to 0. 17 in influent,the nitrogen removal rate decreased from 1. 3kg·( m3·d)- 1to 0. 40 kg·( m3·d)- 1,the decrease range arrived at 69. 3%. The nitrogen conversion efficiency was limited,because of the added amount of HCO-3was decreased,which leading to the p H value declined sharply in nitritation and ANAMMOX zone. In the partial nitritation-ANAMMOX process,the effect of HCO-3limitation on activity of ammonium oxidizing bacteria,ANAMMOX bacteria and nitrifying bacteria was decreased in turn. When the C / N ratio increased to 1,the nitrogen removal rate of combined process was quickly restored to 1 kg·( m3·d)- 1. It indicated that short HCO-3limitation on nitrogen conversion efficiency of the combined process can be fast recovery. The resulted also showed that the relationship between influent C / N ratio and nitrogen removal efficiency has obvious relativity in partial nitritation-ANAMMOX process.