DO和pH值在短程硝化中的作用

在SBR反应器中对DO和pH值在短程硝化和半亚硝化过程中的作用进行试验研究,结果表明,控制低DO和适宜的pH值在短程硝化过程中起着重要的作用.本试验条件下,当DO为0.5～1.0 mg/L、pH值为7.5～8.0时,在SBR反应器中很容易实现短程硝化;当DO＞0.3 mg/L时,DO越低,出水NO2--N积累率越高;当pH值＞6.8时,不会影响系统NO2--N积累的稳定性.另外,研究结果还表明,通过控制DO和pH值可以实现半亚硝化.本试验条件下,当进水氨氮浓度为120 mg/L时,控制DO为0.3～0.4 mg/L可实现出水半亚硝化;当进水氨氮浓度为200 mg/L时,控制DO为0.5～0.6 mg/L或pH值为6.8也可以实现出水半亚硝化.

Effects of DO and pH on nitrosofication

Experimental study about the effects of DO and pH on nitrosofication and half-nitrosofication was carried out in a laboratory-scale sequencing batch reactor(SBR).The results demonstrated that controlling low DO and appropriate pH was very important in the course of nitrosofication.Under the condition that DO was 0.5~1.0 mg/L and pH was 7.0~7.5,nitrosofication could be easily achieved in SBR.If DO was more than(0.3 mg/L,) the lower DO was,the higher NO~-_2-N accumulation rate was.And stable NO~-_2-N accumulation rate would be maintained if pH was more than 6.8.In addition,the results also showed that controlling DO and pH was an effective means to realize half-nitrosofication.Half-nitrosofication could be attained under the condition that DO was 0.3~0.4 mg/L when ammonium concentration in influent was 120 mg/L and under the condition that DO was 0.5~0.6 mg/L or pH was 6.8 when ammonium concentration in influent was 200 mg/L.