硝化动力学研究进展

Kinetic Study of Nitrification

硝化反应包括NH4+氧化为NO2-和NO2-氧化为NO3-两步,其中NH4+到NO2-的氧化不是唯一的限制步骤;已发现叠氮化钠(NaN3)能有效的抑制亚硝酸盐氧化;丙烯基硫脲(ATU)抑制氨氧化反应。用呼吸仪的综合参数——细菌最大氧吸收速率(OURm ax/X)来描绘好氧氨氧化菌和亚硝酸盐氧化菌的比生长速率具有准确性和唯一性,并得到了较多学者一致认可。浓度较高的氨氮和亚硝态氮分别抑制氨氧化反应和亚硝酸盐氧化反应,用抑制性动力学方程来分别描述高浓度氨氮浓度和亚硝态氮浓度对氨氧化反应和亚硝酸盐氧化反应的影响;对比氨氧化动力学和亚硝酸盐氧化动力学参数值与一步硝化动力学参数值可以看出,参数值差异较大;因此,要准确地描述NH4+氧化为NO3-的动力学模型,必须将氨氧化与亚硝酸盐氧化反应独立出来,将NH4+氧化为NO2-和NO2-氧化为NO3-这两步综合在一个反应动力学公式里是错误的。

Nitrification involves the sequential biological oxidation of reduced nitrogen species such as ammonium -nitrogen （ NH4 ） to nitrite - nitrogen （ NO2^-） and nitrate - nitrogen （ NO3^-）, and NH4^＋ to NO2^- oxidation Was not the sole rate - limiting step. It has been found that Azide （ NaN3 ） could inhibit NO2^- to NO3^- oxidation and Allylthiourea （ATU） could inhibit NH4^＋ to NO2^- oxidatiom A lost of researchers thought that only the parameter combination representing maximum speeifie oxygen uptake rate （0URmax/X） is uniquely identifiable from bateh respirograms for the maximum specific growth rate coefficient of autotrophic aerobic ammonia oxidation bacteria and nitrite oxidation bacteria. High ammonium nitrogen and nitrite nitrogen could inhibit ammonium oxidation and nitrite oxidation, respectively. The effect of high ammonium nitrogen and nitrite rfitrogen to ammonium oxidation and nitrite oxidation can be described by itthibitions model, respectively. Compared the kinetic parameters of ammonium oxidation and nitrite oxidation with the kinetic parameters of nitrification, the difference was big. Therefore, the adequacy of modeling NH~＋ to NO[ oxidation as one composite bioehemieal reaction was examined at different relative dynamics of NH4 to NO; and NO; to NO3 oxidation. The use of singlestep models to describe batch NH4 to NO3^- xidation yields erroneous kinetic parameters.