采用间歇实验,考察了初始NH4-N浓度、DO浓度和pH对颗粒污泥完全自营养脱氮的特性的影响。研究表明,在完全自营养脱氮系统中,当DO为0.6~0.8mg/L,pH控制在7.5~7.8时,好氧氨氧化和厌氧氨氧化速率在一定范围内随NH4^+-N浓度(30~150mg/L)的增加而增加,较高的氨氮浓度能提高自营养脱氮反应速率。较高的DO有利于提高亚硝酸盐氧化速率,但会导致亚硝酸盐的积累;DO浓度过低时,好氧氨氧化过程受到抑制。NH4浓度为36mg/L,DO控制在0.6~0.8mg/L的条件下,当pH值为7.8时,完全自营养脱氮的效果最佳,总氮去除速率达最大值为23.976mg/(gMLSS·d)。
The effects of the initial NH4+-N, DO and pH on the completely autotrophic nitrogen removal performance of the granular sludge were investigated in batch experiments. The results shown that, in the system of completely autotrophic nitrogen removal, when DO was 0.6 - 0. 8 mg/L and pH was 7.5 - 7.8, aerobic and anaerobic ammonium oxidation rates increased with NH4^+-N concentration in the range of 30 - 150 mg/L. The higher NH4^+ -N concentration raised the rates of completely autotrophic nitrogen removal. The much higher DO increased nitrite oxidation rate, and resulted in the accumulation of NO3^-. The much lower DO inhibited aerobic ammonium oxidation. When the concentration of NH4^+-N was 36 mg/L, DO was 0.6 -0.8 mg/L, and pH was 7.8, total nitrogen removal rate reached the maximum of 23. 976 mg/(g MLSS·d).