Effect of alkalinity on the [NH_4~+-N] ratio during partial nitrification in a sequencing batch reactor

Partial nitrification in a sequering batch reactor is sensitive to the alkalinity.Experimental test on the effect of alkalinity on [NH+4-N] ratio during partial nitrification shows that low alkalinity environments are not conducive to ammonia-oxidizing bacteria's activity during the nitritation.As a result,the nitritation process ceased.Therefore,the pH and the dissolved oxygen can be used to control the nitrification process with the alkalinity used to control the nitrification to achieve half-nitritation.The batch experimental results indicate that the [NH+4-N] removal rate is related with the initial alkalinity and that reductions in the pH value stop the nitritation process.