催化铁强化低碳废水生物反硝化过程的探讨

研究了低碳氮比条件下催化铁耦合生物反硝化的脱氮效率以及N2O产生.结果表明,相对常规低碳氮比反硝化,催化铁耦合组能大大提高硝酸根的转化率,但产生亚硝态氮积累,总氮去除率变化不大.耦合组N2O释放量高于常规生物对照组,源于亚铁氧化物与亚硝酸根的化学反应,但最高累积量小于8%,且可继续生物还原为N2.催化铁可以消除体系的溶解氧和降低氧化还原电位,对维持缺氧反硝化环境有利.

Investigation of Enhanced Low Carbon Wastewater Denitrification by Catalytic Iron

The nitrogen removal efficiency and N₂O production during the process of coupling catalytic iron and biological denitrification for low C/N ratio wastewater were studied. The results showed that biological denitrification coupled with catalytic iron could significantly improve nitrate transforming efficiency, but led to nitrite accumulation, resulting in little difference in total nitrogen removal efficiency, compared with traditional biological denitrification. N₂O production from the catalytic iron group was obviously higher than the traditional control group, among which chemical reaction between ferrous oxide and nitrite had great contribution. However, the highest amount of accumulated N₂O was less than 8% of the removed nitrate, and N₂O was further reduced to N₂ by microorganisms. Furthermore, catalytic iron group could eliminate dissolved oxygen and lower the oxidation reduction potential, which is beneficial for keeping anoxic conditions during denitrification.