重金属离子对亚硝化的影响研究

The Impact of Metal Ions on Nitrosification

研究Mn^(2+)质量浓度对亚硝化的影响,确定在Mn^(2+)条件下实现亚硝化的运行参数。采用实际生活污水,pH控制在7.0~8.0,温度维持在28℃,DO质量浓度为1.0 mg/L。通过静态实验在不同Mn^(2+)质量浓度(5、10、15、20mg/L)条件下,研究NH_4^+-N的去除效果和NO_2^--N累积效果。Mn^(2+)质量浓度在5~10 mg/L时,NH_4^+-N去除率和NO_2^--N累积率稳定在80%以上。当Mn^(2+)质量浓度超过15 mg/L时,NH_4^+-N去除率只能维持在60%以上,NO_2^--N累积率最低时只有21.157%。低浓度的Mn^(2+)通过微生物所需微量元素形式促进亚硝化细菌的活性,但是高浓度的Mn^(2+)会发挥其重金属离子的毒性作用,抑制亚硝化细菌的活性。

This paper aims to study on the impact of Mn^2＋ on nitrosification to determine the optimum operating parameters of nitrosification at different Mn^2＋ condition.The experiment uses real life wastewater,under the condition of pH value in 7.0-8.0,controlling temperature at 28℃,DO concentration was 1.0 mg/L.Using static tests investigated NH4^＋-N removal case and NO2-N accumulation case under the condition of different Mn^2＋ concentration（5,10,15,20 mg/L）and different COD mass concentration（50,100,150,200 mg/L）.The NH4^＋-N removal rate and NO2^--N accumulation rate was stable at80%respectively when the Mn^2＋ concentration was 5-10 mg/L.The NH4^＋-N removal rate only stable at 60%and NO2^--N accumulation dropped at21.157%when the Mn^2＋ concentration above 15 mg/L.The Mn^2＋ could accelerate the activity of nitrosated bacterial by the trace of Mn^2＋ when the Mn^2＋concentration was low,but organic carbon concentration is too high will inhibit the activity of nitrosated bacterial by the Mn^2＋ as heavy metal.