乙酸钠为电子供体时反硝化耦合甲烷化过程的数学模拟

基于化学计量学与生物力能学确定生化反应的理论反应式,结合multiplicative Monod及non-competitive Monod方程,建立了反硝化耦合甲烷化的数学模型。以乙酸钠为电子供体,厌氧颗粒污泥为接种污泥,通过间歇实验获取模型的相关参数。结果表明:该模型能较好地分析反硝化耦合甲烷化过程底物降解、竞争规律及反硝化中间产物对甲烷化的抑制作用;预测气体的累积产气量及各菌群生物量变化。参数灵敏度分析表明:甲烷化、硝酸盐还原和亚硝酸盐过程的灵敏度因子分别为km,a、km,NO3和km,NO2,这证实最大比底物利用速率对底物降解过程影响最显著,其值分别为km,a=0.098 h-1,km,NO3=0.0824 h-1和km,NO2=0.0695 h-1。

MATHEMATICAL SIMULATION OF SIMULTANEOUS DENITRIFICATION AND METHANOGENESIS WITH SODIUM ACETATE AS THE ELECTRON DONOR

The multiplicative Monod and non-competitive Monod equation were integrated with theoretical equations determined by stoichiometry and bioenergetics to analysis the simultaneous denitrification and methanogenesis ( SDM) process． Batch experiment was used to obtain the model parameters with sodium acetate as the electron donor and anaerobic granular sludge as seed sludge． The degradation and competition of substrate as well as the inhibitory effect of N-oxides on methanogenesis in the SDM process could be well described using the above models． Furthermore，the cumulative gas production and changes in biomass of each microbial community were predicted． Parametric sensitivity analysis indicated that km，a ，k m，NO3 and km，NO2 were sensitivity factor for methanogenesis，denitratation and denitritation process and their the values were 0. 098 h － 1 ，0. 0824 h － 1 and 0. 0695 h － 1 ，respectively． The results suggested that the maximum specific substrate utilization rate had the most significant effect on the substrate degradation process．