Abstract: In treating simulation coking wastewater in upflow blanket filter(UBF),addition of NaNO₃ in water for simulating backflow of nitrification liquid results in simultaneous methanogenesis and denitrification,along with COD removal rate 94%,and NO₃^--N removal efficiency 99%.In denitrification dynamics research of the sludge at the bottom of the UBF,double-substrates Monod model was adopted to fit the test data obtained under conditions of nitrite accumulation,NO₃^--N+0.6NO₂^--N as the electronic acceptor of denitrification.The results show that there is a good correlation between the fitting curve and the experimental measurement.Then differential model based on Monod model was used to fit the change in the concentration of NO₃^--N and NO₂^--N respectively,relevant parameters obtained were as follows:The maximum specific degradation rate and half-saturation constant are 1.13 d^-1 and 2.0 mg·L^-1 for NO₃^--N,and 0.66 d^-1 and 2.5 mg·L^-1for NO₂^--N.The half-saturation constant of organic substrate based upon NO₃^--N and NO₂^--N are 90.8 mg·L^-1 and 96.8 mg·L^-1.

Key words: coking wastewater, denitrification dynamics, nitrite accumulation

摘要： 采用厌氧复合床(UBF)处理模拟焦化废水,进水中投加NaNO₃模拟硝化液回流,实现了同时反硝化/产甲烷,COD去除率达到94%,NO₃^--N去除率达到99%。取复合床下部污泥做反硝化动力学研究,在存在亚硝酸盐积累的情况下,以NO₃^--N+0.6NO₂^--N作为反硝化电子受体,采用双基质的Monod方程对实验数据进行拟合,拟合曲线与实验测定值相关性良好。其次,采用双基质的Monod微分方程组对NO₃^--N和NO₂^--N的浓度变化进行拟合,得到相关参数:硝态氮的最大比降解速率和半饱和常数分别为1.13 d^-1和2.0 mg·L^-1;亚硝态氮的最大比降解速率和半饱和常数分别为0.66 d^-1和2.5 mg·L^-1,基于硝态氮和亚硝态氮的有机物半饱和常数分别为90.8 mg·L^-1和96.8 mg·L^-1。

关键词: 焦化废水, 反硝化动力学, 亚硝酸盐积累