基质浓度对ABR厌氧氨氧化反硝化脱氮除碳效能影响及动力学特征

采用厌氧折流板反应器(ABR)为研究对象,以一定COD、NH+4-N和NO-2-N比例增加进水基质浓度,以明确基质负荷提高对ABR厌氧氨氧化和反硝化协同体系脱氮除碳的影响,并通过基质去除模型获得反应器对基质的耐受程度.研究表明,ABR反应器能够实现厌氧氨氧化反硝化耦合脱氮除碳,当进水基质COD、NO-2-N和NH+4-N浓度从220、168和60 mg·L~(-1)提高至420、270和110 mg·L~(-1)时,反应器脱氮效能下降,COD、NO-2-N、NH+4-N和TN去除率分别为97%、94%、30%和78%,厌氧氨氧化对TN去除的贡献率从43.08%骤降至16.49%,反硝化脱氮贡献率从53.81%增至82.07%.动力学模型拟合发现,Stover-Kincannon模型(R2=0.937,TN;R2=0.975,COD)较一级基质去除模型(R2=0.314,TN;R2=0.016,COD)更适合评价反应器对基质的承受力;Stover-Kincannon模型表明,反应器对TN和COD的最大基质利用率分别为1.43 g·L-1·d-1和3.33 g·L-1·d-1,饱和常数(KB)分别为1.2和3.79,研究认为ABR协同脱氮除碳体系理论上还有继续提升基质负荷的潜力.

The nitrogen/carbon removal and kinetic characteristics of ABR anammox reactor under different substrate concentrations

In order to identify the synergistic anammox and denitrification process in anaerobic baffled reactor (ABR), the concentrations of COD, NO₂^--N and NH₄⁺-N were controlled to investigate the effect of substrate concentrations on nitrogen and carbon removal. The results show that the removal efficiencies of COD, NO₂^--N, NH₄⁺-N and TN were about 97%, 94%, 30% and 78%, respectively when the influent COD, NO₂^--N, NH₄⁺-N concentrations were increased from 220, 168 and 60 mg·L^-1 to 420, 270 and 110 mg·L^-1. With the influent substrate concentrations increased, the contribution of Anammox to TN removal decreased from 43.08% to 16.49%,while the contribution of denitrification increased from 53.81% to 82.07%. The kinetic analysis results show the Stover-Kincannon model (R²=0.937,TN;R²=0.975,COD) is more appropriate than the First-order substrate removal model (R²=0.314, TN; R²=0.016, COD) to describe the tolerance of substrates on the system. The maximum TN and COD utilization rate obtained by Stover-Kincannon model was 1.43 g·L^-1·d^-1 and 3.33 g·L^-1·d^-1, while the saturation constant (K_B) was 1.2 and 3.79, respectively. Therefore, it is believed that the ABR, which acts as a synergistic denitrification and decarbonization system, has the potential of increasing the matrix load.